Refactoring dashboard.js, splitting monolithic file into multiple source files. (#4496)

* Mild cleanup of dashboard.js (#4461)

* Balancing of else clauses

* More cleanup, fixed nasty bug introduced by previous commit

* More cleanup

* More refactoring

* Wip

* More refactoring

* Wip

* Cleanup, wip

* Refactor for-loop

* Remove .hasOwnProperties, wip

* Split dashboard.js into multiple files, wip #4479

* Fixed a bug in common min/max

* Extracted more files from dashboard.js

* Extracted more code, wip

* Extract units-conversion.js and sparkline.js

* Do not include morris.js, c3.js and raphael.js in dashbaord.js

They are extracted as separate files but not included in dashboards.js

* Removed refs to obsolete charting libraries #4492

* Extracted google-charts #4479

* Extracted google-charts

* Removed refs to morris, c3, raphael from dashboard.html

* Wip #4479

* Extracted more charting libraries, cleanup

* Organize charting libs in subfolder

* Apply WebStorm formatter (mostly adds missing braces)

* Additional formatting with WebStorm #4461

* Extracted d3pie, peity, localstorage

* Extracted options.js, fixed some issues with dependencies, wip

* Extracted boot.js

* Fixes in for loops #4461

* Removed extrtacted d3pie from main file

* Extracted registry.js

* Extracted alarms.js

* Extracted error-handling.js

* Extracted fast formatting to utils.js

* Extracted chart libraries registration code

* Extracted some js/css loading code into boot.js

* Added some info on generating dashboard.js

* Fixed issues reported by LGTM

* Minor

* added slitted dashboard.js to makefiles

* updated merged dashboard.js

* excluded paths from codacy

* minor pending fixes

* updated README.md for release 1.11

.codacy.yml

@@ -4,9 +4,9 @@ exclude_paths:
   - collectors/python.d.plugin/python_modules/pyyaml3/**
   - collectors/python.d.plugin/python_modules/urllib3/**
   - collectors/python.d.plugin/python_modules/third_party/**
-  - web/css/**
-  - web/lib/**
-  - web/old/**
-  - web/gui/src/**
   - collectors/node.d.plugin/node_modules/**
+  - web/gui/css/**
+  - web/gui/lib/**
+  - web/gui/old/**
+  - web/gui/src/**
   - tests/**

README.md

@@ -64,6 +64,22 @@ netdata currently runs on **Linux**, **FreeBSD**, and **MacOS**.
 
 ## News
 
+`Nov 6th, 2018` - **[netdata v1.11.0 released!](https://github.com/netdata/netdata/releases)**
+
+ - New query engine, supporting statistical functions.
+ - Fixed security issues identified by Red4Sec.com and Synacktiv.
+ - New Data Collection Modules: `rethinkdbs`, `proxysql`, `litespeed`, `uwsgi`, `unbound`, `powerdns`, `dockerd`, `puppet`, `logind`, `adaptec_raid`, `megacli`, `spigotmc`, `boinc`, `w1sensor`, `monit`, `linux_power_supplies`.
+ - Improved Data Collection Modules: `statsd.plugin`, `apps.plugin`, `freeipmi.plugin`, `proc.plugin`, `diskspace.plugin`, `freebsd.plugin`, `python.d.plugin`, `web_log`, `nginx_plus`, `ipfs`, `fail2ban`, `ceph`, `elasticsearch`, `nginx_plus`,  `redis`, 
+ `beanstalk`, `mysql`, `varnish`, `couchdb`, `phpfpm`, `apache`, `icecast`, `mongodb`, `postgress`, `elasticsearch`, `mdstat`, `openvpn_log`, `snmp`, `nut`.
+
+ - Added alarms for detecting abnormally high load average, `TCP` `SYN` and `TCP` accept queue overflows, network interfaces congestion and alarms for `bcache`, `mdstat`, `apcupsd`, `mysql`.
+ - system alarms are now enabled on FreeBSD.
+ - New notification methods: **rocket.chat**, **Microsoft Teams**, **syslog**, **fleep.io**, **Amazon SNS**.
+
+ - and dozens more improvements, enhancements, features and compatibility fixes
+
+---
+
 `Sep 18, 2018` - **netdata has its own organization**
 
 Netdata used to be a [firehol.org](https://firehol.org) project, accessible as `firehol/netdata`.
@@ -82,50 +98,6 @@ Read the [netdata presentation](https://docs.google.com/presentation/d/18C8bCTbt
 
 ---
 
-`Mar 27th, 2018` - **[netdata v1.10.0 released!](https://github.com/netdata/netdata/releases)**
-
- - new web server, a lot faster and more secure
- - updated all javascript libraries to their latest versions (fixed compatibility issues - now netdata chart can now be embedded on **Atlassian Confluence** pages and remain fully interactive!)
- - new plugins:
-   - **BTRFS** (visualize BTRFS allocation with alarms)
-   - **bcache** (monitor hybrid setups HDD + SSD)
-   - **ceph**
-   - **nginx plus**
-   - **libreswan** (monitor the traffic of IPSEC tunnels)
-   - **traefik**
-   - **icecast**
-   - **ntpd**
-   - **httpcheck** (monitor any remote web server)
-   - **portcheck** (monitor any remote TCP port)
-   - **spring-boot** (monitor java spring-boot apps)
-   - **dnsdist**
-   - **Linux hugepages**
- - improved plugins:
-   - **statsd**
-   - **web_log**
-   - **cgroups** for containers and VMs monitoring (netdata now supports **systemd-nspawn** and **kubernetes** - fixed security issue with `cgroup-network`)
-   - **Linux memory**
-   - **diskspace**
-   - **network interfaces**
-   - **postgres**
-   - **rabbitmq**
-   - **apps.plugin** (now it also tracks swap usage per process)
-   - **haproxy**
-   - **uptime**
-   - **ksm** (kernel memory debupper)
-   - **mdstat** (software raid)
-   - **elasticsearch**
-   - **apcupsd**
-   - **dhcpd**
-   - **fronius**
-   - **stiebeletron**
- - new alarm notification methods
-   - **alerta**
-   - **IRC** (post on IRC channels)
- - and dozens more improvements, enhancements, features and compatibility fixes
-
----
-
 ## Features
 
 <p align="center">

diagrams/Makefile.am

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
+
 MAINTAINERCLEANFILES= $(srcdir)/Makefile.in
 
 dist_noinst_DATA = \
@@ -7,6 +8,15 @@ dist_noinst_DATA = \
 	netdata-for-ephemeral-nodes.xml \
 	netdata-proxies-example.xml \
 	netdata-overview.xml \
+	data_structures/netdata_config.svg \
+	data_structures/README.md \
+	data_structures/registry.svg \
+	data_structures/rrd.svg \
+	data_structures/web.svg \
+	data_structures/src/netdata_config.xml \
+	data_structures/src/registry.xml \
+	data_structures/src/rrd.xml \
+	data_structures/src/web.xml \
 	$(NULL)
 
 dist_noinst_SCRIPTS = \

web/gui/Makefile.am

@@ -3,9 +3,40 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 #
 MAINTAINERCLEANFILES= $(srcdir)/Makefile.in
+CLEANFILES = \
+	dashboard.js \
+	version.txt \
+	$(NULL)
+
+DASHBOARD_JS_FILES = \
+    src/dashboard.js/prologue.js.inc \
+    src/dashboard.js/utils.js \
+    src/dashboard.js/error-handling.js \
+    src/dashboard.js/compatibility.js \
+    src/dashboard.js/xss.js \
+    src/dashboard.js/colors.js \
+    src/dashboard.js/units-conversion.js \
+    src/dashboard.js/options.js \
+    src/dashboard.js/localstorage.js \
+    src/dashboard.js/charting/dygraph.js \
+    src/dashboard.js/charting/sparkline.js \
+    src/dashboard.js/charting/google-charts.js \
+    src/dashboard.js/charting/gauge.js \
+    src/dashboard.js/charting/easy-pie-chart.js \
+    src/dashboard.js/charting/d3pie.js \
+    src/dashboard.js/charting/d3.js \
+    src/dashboard.js/charting/peity.js \
+    src/dashboard.js/charting.js \
+    src/dashboard.js/main.js \
+    src/dashboard.js/alarms.js \
+    src/dashboard.js/registry.js \
+    src/dashboard.js/boot.js \
+    src/dashboard.js/epilogue.js.inc \
+    $(NULL)
 
 dist_noinst_DATA = \
 	README.md \
+	$(DASHBOARD_JS_FILES) \
 	$(NULL)
 
 dist_web_DATA = \
@@ -103,6 +134,9 @@ dist_webimages_DATA = \
 	images/seo-performance-multi-size.icns \
 	$(NULL)
 
+dashboard.js: $(DASHBOARD_JS_FILES)
+	if test -f $@; then rm -f $@; fi
+	cat $(DASHBOARD_JS_FILES) > $@.tmp && mv $@.tmp $@
 
 webwellknowndir=$(webdir)/.well-known
 dist_webwellknown_DATA = \
@@ -120,4 +154,5 @@ version.txt:
 	test -s $@.tmp || echo 0 > $@.tmp
 	mv $@.tmp $@
 
-.PHONY: version.txt
+# regenerate these files, even if they are up to date
+.PHONY: version.txt dashboard.js

web/gui/README.md

@@ -1,3 +1,12 @@
-# Web GUI
+# Netdata Agent Web GUI
 
-A Graphical User Interface for visualizing data collected by Netdata.
+## Generating dashboard.js
+
+The monolithic `dashboards.js` file is automatically generated by concatenating the source files located in the `web/gui/src` directory by running the build script:
+
+```sh
+cd web/gui
+./build-dashboard-js.sh
+```
+
+After every change in the `src` directory, the `dashboard.js` file should be regenerated and commited to the repository.

web/gui/dashboard.html

@@ -56,7 +56,7 @@ This is a template for building custom dashboards. To build a dashboard you just
     <li>You can host your dashboard anywhere.</li>
     <li>You can add as many charts as you like.</li>
     <li>You can have charts from many different netdata servers (add <pre>data-host="http://another.netdata.server:19999/"</pre> to each chart).</li>
-    <li>You can use different chart libraries on the same page: <b>peity</b>, <b>sparkline</b>, <b>dygraph</b>, <b>google</b>, <b>morris</b></li>
+    <li>You can use different chart libraries on the same page: <b>peity</b>, <b>sparkline</b>, <b>dygraph</b>, <b>google</b></li>
     <li>You can customize each chart to your preferences. For each chart library most of their attributes can be given in <b>data-</b> attributes.</li>
     <li>Each chart can have each own duration - it is controlled with the <b>data-after</b> attribute to give that many seconds of data.</li>
     <li>Depending on the width of the chart and <b>data-after</b> attribute, netdata will automatically refresh the chart when it needs to be updated. For example giving 600 pixels for width for -600 seconds of data, using a chart library that needs 3 pixels per point, will yeld in a chart updated once every 3 seconds.</li>
@@ -555,11 +555,8 @@ NetData is a complete Google Visualization API provider.
     <small>rendered in <span id="time303">X</span> ms</small>
 </div>
 
-
-
-
-
-
+<!--
+    
 <hr>
 <h1>Morris Charts</h1>
 Unfortunatelly, Morris Charts are very slow. Here we force them to lower their detail to get acceptable results.
@@ -644,6 +641,7 @@ So, to avoid flashing the charts, we destroy and re-create the charts on each up
     <small>rendered in <span id="time803">X</span> ms</small>
 </div>
 
+-->
 
     <hr>
     <h1>d3pie Charts</h1>

web/gui/dashboard.js

@@ -1,7 +1,12 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
+
+// DO NOT EDIT: This file is automatically generated from the source files in src/
+
 // ----------------------------------------------------------------------------
 // You can set the following variables before loading this script:
 
+// 'use strict';
+
 /*global netdataNoDygraphs           *//* boolean,  disable dygraph charts
  *                                                  (default: false) */
 /*global netdataNoSparklines         *//* boolean,  disable sparkline charts
@@ -72,9441 +77,9975 @@
 // ----------------------------------------------------------------------------
 // global namespace
 
-var NETDATA = window.NETDATA || {};
+const NETDATA = window.NETDATA || {};
 
 (function(window, document, $, undefined) {
 
-    NETDATA.encodeURIComponent = function(s) {
-        if(typeof(s) === 'string')
-            return encodeURIComponent(s);
+NETDATA.encodeURIComponent = function (s) {
+    if (typeof(s) === 'string') {
+        return encodeURIComponent(s);
+    }
 
-        return s;
-    };
+    return s;
+};
 
-    // ------------------------------------------------------------------------
-    // compatibility fixes
+/// A heuristic for detecting slow devices.
+let isSlowDeviceResult = undefined;
+const isSlowDevice = function () {
+    if (!isSlowDeviceResult) {
+        return isSlowDeviceResult;
+    }
 
-    // fix IE issue with console
-    if(!window.console) { window.console = { log: function(){} }; }
+    try {
+        let ua = navigator.userAgent.toLowerCase();
 
-    // if string.endsWith is not defined, define it
-    if(typeof String.prototype.endsWith !== 'function') {
-        String.prototype.endsWith = function(s) {
-            if(s.length > this.length) return false;
-            return this.slice(-s.length) === s;
-        };
+        let iOS = /ipad|iphone|ipod/.test(ua) && !window.MSStream;
+        let android = /android/.test(ua) && !window.MSStream;
+        isSlowDeviceResult = (iOS || android);
+    } catch (e) {
+        isSlowDeviceResult = false;
     }
 
-    // if string.startsWith is not defined, define it
-    if(typeof String.prototype.startsWith !== 'function') {
-        String.prototype.startsWith = function(s) {
-            if(s.length > this.length) return false;
-            return this.slice(s.length) === s;
-        };
-    }
+    return isSlowDeviceResult;
+};
 
-    NETDATA.name2id = function(s) {
-        return s
-            .replace(/ /g, '_')
-            .replace(/\(/g, '_')
-            .replace(/\)/g, '_')
-            .replace(/\./g, '_')
-            .replace(/\//g, '_');
-    };
+NETDATA.guid = function () {
+    function s4() {
+        return Math.floor((1 + Math.random()) * 0x10000)
+            .toString(16)
+            .substring(1);
+    }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // XSS checks
-
-    NETDATA.xss = {
-        enabled: (typeof netdataCheckXSS === 'undefined')?false:netdataCheckXSS,
-        enabled_for_data: (typeof netdataCheckXSS === 'undefined')?false:netdataCheckXSS,
-
-        string: function (s) {
-            return s.toString()
-                .replace(/</g, '&lt;')
-                .replace(/>/g, '&gt;')
-                .replace(/"/g, '&quot;')
-                .replace(/'/g, '&#39;');
-        },
+    return s4() + s4() + '-' + s4() + '-' + s4() + '-' + s4() + '-' + s4() + s4() + s4();
+};
 
-        object: function(name, obj, ignore_regex) {
-            if(typeof ignore_regex !== 'undefined' && ignore_regex.test(name) === true) {
-                // console.log('XSS: ignoring "' + name + '"');
-                return obj;
+NETDATA.zeropad = function (x) {
+    if (x > -10 && x < 10) {
+        return '0' + x.toString();
+    } else {
+        return x.toString();
+    }
+};
+
+NETDATA.seconds4human = function (seconds, options) {
+    let default_options = {
+        now: 'now',
+        space: ' ',
+        negative_suffix: 'ago',
+        day: 'day',
+        days: 'days',
+        hour: 'hour',
+        hours: 'hours',
+        minute: 'min',
+        minutes: 'mins',
+        second: 'sec',
+        seconds: 'secs',
+        and: 'and'
+    };
+
+    if (typeof options !== 'object') {
+        options = default_options;
+    } else {
+        for (const x in default_options) {
+            if (typeof options[x] !== 'string') {
+                options[x] = default_options[x];
             }
+        }
+    }
 
-            switch (typeof(obj)) {
-                case 'string':
-                    var ret = this.string(obj);
-                    if(ret !== obj) console.log('XSS protection changed string ' + name + ' from "' + obj + '" to "' + ret + '"');
-                    return ret;
+    if (typeof seconds === 'string') {
+        seconds = parseInt(seconds, 10);
+    }
 
-                case 'object':
-                    if(obj === null) return obj;
+    if (seconds === 0) {
+        return options.now;
+    }
 
-                    if(Array.isArray(obj) === true) {
-                        // console.log('checking array "' + name + '"');
+    let suffix = '';
+    if (seconds < 0) {
+        seconds = -seconds;
+        if (options.negative_suffix !== '') {
+            suffix = options.space + options.negative_suffix;
+        }
+    }
 
-                        var len = obj.length;
-                        while(len--)
-                            obj[len] = this.object(name + '[' + len + ']', obj[len], ignore_regex);
-                    }
-                    else {
-                        // console.log('checking object "' + name + '"');
+    let days = Math.floor(seconds / 86400);
+    seconds -= (days * 86400);
 
-                        for(var i in obj) {
-                            if(obj.hasOwnProperty(i) === false) continue;
-                            if(this.string(i) !== i) {
-                                console.log('XSS protection removed invalid object member "' + name + '.' + i + '"');
-                                delete obj[i];
-                            }
-                            else
-                                obj[i] = this.object(name + '.' + i, obj[i], ignore_regex);
-                        }
-                    }
-                    return obj;
+    let hours = Math.floor(seconds / 3600);
+    seconds -= (hours * 3600);
 
-                default:
-                    return obj;
-            }
-        },
+    let minutes = Math.floor(seconds / 60);
+    seconds -= (minutes * 60);
 
-        checkOptional: function(name, obj, ignore_regex) {
-            if(this.enabled === true) {
-                //console.log('XSS: checking optional "' + name + '"...');
-                return this.object(name, obj, ignore_regex);
-            }
-            return obj;
-        },
+    let strings = [];
 
-        checkAlways: function(name, obj, ignore_regex) {
-            //console.log('XSS: checking always "' + name + '"...');
-            return this.object(name, obj, ignore_regex);
-        },
+    if (days > 1) {
+        strings.push(days.toString() + options.space + options.days);
+    } else if (days === 1) {
+        strings.push(days.toString() + options.space + options.day);
+    }
 
-        checkData: function(name, obj, ignore_regex) {
-            if(this.enabled_for_data === true) {
-                //console.log('XSS: checking data "' + name + '"...');
-                return this.object(name, obj, ignore_regex);
-            }
-            return obj;
-        }
-    };
+    if (hours > 1) {
+        strings.push(hours.toString() + options.space + options.hours);
+    } else if (hours === 1) {
+        strings.push(hours.toString() + options.space + options.hour);
+    }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Detect the netdata server
+    if (minutes > 1) {
+        strings.push(minutes.toString() + options.space + options.minutes);
+    } else if (minutes === 1) {
+        strings.push(minutes.toString() + options.space + options.minute);
+    }
+
+    if (seconds > 1) {
+        strings.push(Math.floor(seconds).toString() + options.space + options.seconds);
+    } else if (seconds === 1) {
+        strings.push(Math.floor(seconds).toString() + options.space + options.second);
+    }
+
+    if (strings.length === 1) {
+        return strings.pop() + suffix;
+    }
 
-    // http://stackoverflow.com/questions/984510/what-is-my-script-src-url
-    // http://stackoverflow.com/questions/6941533/get-protocol-domain-and-port-from-url
-    NETDATA._scriptSource = function() {
-        var script = null;
+    let last = strings.pop();
+    return strings.join(", ") + " " + options.and + " " + last + suffix;
+};
 
-        if(typeof document.currentScript !== 'undefined') {
-            script = document.currentScript;
+// ----------------------------------------------------------------------------------------------------------------
+// element data attributes
+
+NETDATA.dataAttribute = function (element, attribute, def) {
+    let key = 'data-' + attribute.toString();
+    if (element.hasAttribute(key)) {
+        let data = element.getAttribute(key);
+
+        if (data === 'true') {
+            return true;
         }
-        else {
-            var all_scripts = document.getElementsByTagName('script');
-            script = all_scripts[all_scripts.length - 1];
+        if (data === 'false') {
+            return false;
+        }
+        if (data === 'null') {
+            return null;
         }
 
-        if (typeof script.getAttribute.length !== 'undefined')
-            script = script.src;
-        else
-            script = script.getAttribute('src', -1);
-
-        return script;
-    };
+        // Only convert to a number if it doesn't change the string
+        if (data === +data + '') {
+            return +data;
+        }
 
-    if(typeof netdataServer !== 'undefined')
-        NETDATA.serverDefault = netdataServer;
-    else {
-        var s = NETDATA._scriptSource();
-        if(s) NETDATA.serverDefault = s.replace(/\/dashboard.js(\?.*)?$/g, "");
-        else {
-            console.log('WARNING: Cannot detect the URL of the netdata server.');
-            NETDATA.serverDefault = null;
+        if (/^(?:\{[\w\W]*\}|\[[\w\W]*\])$/.test(data)) {
+            return JSON.parse(data);
         }
+
+        return data;
+    } else {
+        return def;
     }
+};
 
-    if(NETDATA.serverDefault === null)
-        NETDATA.serverDefault = '';
-    else if(NETDATA.serverDefault.slice(-1) !== '/')
-        NETDATA.serverDefault += '/';
+NETDATA.dataAttributeBoolean = function (element, attribute, def) {
+    let value = NETDATA.dataAttribute(element, attribute, def);
 
-    if(typeof netdataServerStatic !== 'undefined' && netdataServerStatic !== null && netdataServerStatic !== '') {
-        NETDATA.serverStatic = netdataServerStatic;
-        if(NETDATA.serverStatic.slice(-1) !== '/')
-            NETDATA.serverStatic += '/';
+    if (value === true || value === false) // gmosx: Love this :)
+    {
+        return value;
     }
-    else {
-        NETDATA.serverStatic = NETDATA.serverDefault;
-    }
-
-
-    // default URLs for all the external files we need
-    // make them RELATIVE so that the whole thing can also be
-    // installed under a web server
-    NETDATA.jQuery              = NETDATA.serverStatic + 'lib/jquery-2.2.4.min.js';
-    NETDATA.peity_js            = NETDATA.serverStatic + 'lib/jquery.peity-3.2.0.min.js';
-    NETDATA.sparkline_js        = NETDATA.serverStatic + 'lib/jquery.sparkline-2.1.2.min.js';
-    NETDATA.easypiechart_js     = NETDATA.serverStatic + 'lib/jquery.easypiechart-97b5824.min.js';
-    NETDATA.gauge_js            = NETDATA.serverStatic + 'lib/gauge-1.3.2.min.js';
-    NETDATA.dygraph_js          = NETDATA.serverStatic + 'lib/dygraph-c91c859.min.js';
-    NETDATA.dygraph_smooth_js   = NETDATA.serverStatic + 'lib/dygraph-smooth-plotter-c91c859.js';
-    NETDATA.raphael_js          = NETDATA.serverStatic + 'lib/raphael-2.2.4-min.js';
-    NETDATA.c3_js               = NETDATA.serverStatic + 'lib/c3-0.4.18.min.js';
-    NETDATA.c3_css              = NETDATA.serverStatic + 'css/c3-0.4.18.min.css';
-    NETDATA.d3pie_js            = NETDATA.serverStatic + 'lib/d3pie-0.2.1-netdata-3.js';
-    NETDATA.d3_js               = NETDATA.serverStatic + 'lib/d3-4.12.2.min.js';
-    NETDATA.morris_js           = NETDATA.serverStatic + 'lib/morris-0.5.1.min.js';
-    NETDATA.morris_css          = NETDATA.serverStatic + 'css/morris-0.5.1.css';
-    NETDATA.google_js           = 'https://www.google.com/jsapi';
-
-    NETDATA.themes = {
-        white: {
-            bootstrap_css: NETDATA.serverStatic + 'css/bootstrap-3.3.7.css',
-            dashboard_css: NETDATA.serverStatic + 'dashboard.css?v20180210-1',
-            background: '#FFFFFF',
-            foreground: '#000000',
-            grid: '#F0F0F0',
-            axis: '#F0F0F0',
-            highlight: '#F5F5F5',
-            colors: [   '#3366CC', '#DC3912',   '#109618', '#FF9900',   '#990099', '#DD4477',
-                        '#3B3EAC', '#66AA00',   '#0099C6', '#B82E2E',   '#AAAA11', '#5574A6',
-                        '#994499', '#22AA99',   '#6633CC', '#E67300',   '#316395', '#8B0707',
-                        '#329262', '#3B3EAC' ],
-            easypiechart_track: '#f0f0f0',
-            easypiechart_scale: '#dfe0e0',
-            gauge_pointer: '#C0C0C0',
-            gauge_stroke: '#F0F0F0',
-            gauge_gradient: false,
-            d3pie: {
-                title: '#333333',
-                subtitle: '#666666',
-                footer: '#888888',
-                other: '#aaaaaa',
-                mainlabel: '#333333',
-                percentage: '#dddddd',
-                value: '#aaaa22',
-                tooltip_bg: '#000000',
-                tooltip_fg: '#efefef',
-                segment_stroke: "#ffffff",
-                gradient_color: '#000000'
-            }
-        },
-        slate: {
-            bootstrap_css: NETDATA.serverStatic + 'css/bootstrap-slate-flat-3.3.7.css?v20161229-1',
-            dashboard_css: NETDATA.serverStatic + 'dashboard.slate.css?v20180210-1',
-            background: '#272b30',
-            foreground: '#C8C8C8',
-            grid: '#283236',
-            axis: '#283236',
-            highlight: '#383838',
-/*          colors: [   '#55bb33', '#ff2222',   '#0099C6', '#faa11b',   '#adbce0', '#DDDD00',
-                        '#4178ba', '#f58122',   '#a5cc39', '#f58667',   '#f5ef89', '#cf93c0',
-                        '#a5d18a', '#b8539d',   '#3954a3', '#c8a9cf',   '#c7de8a', '#fad20a',
-                        '#a6a479', '#a66da8' ],
-*/
-            colors: [   '#66AA00', '#FE3912',   '#3366CC', '#D66300',   '#0099C6', '#DDDD00',
-                        '#5054e6', '#EE9911',   '#BB44CC', '#e45757',   '#ef0aef', '#CC7700',
-                        '#22AA99', '#109618',   '#905bfd', '#f54882',   '#4381bf', '#ff3737',
-                        '#329262', '#3B3EFF' ],
-            easypiechart_track: '#373b40',
-            easypiechart_scale: '#373b40',
-            gauge_pointer: '#474b50',
-            gauge_stroke: '#373b40',
-            gauge_gradient: false,
-            d3pie: {
-                title: '#C8C8C8',
-                subtitle: '#283236',
-                footer: '#283236',
-                other: '#283236',
-                mainlabel: '#C8C8C8',
-                percentage: '#dddddd',
-                value: '#cccc44',
-                tooltip_bg: '#272b30',
-                tooltip_fg: '#C8C8C8',
-                segment_stroke: "#283236",
-                gradient_color: '#000000'
-            }
-        }
-    };
 
-    if(typeof netdataTheme !== 'undefined' && typeof NETDATA.themes[netdataTheme] !== 'undefined')
-        NETDATA.themes.current = NETDATA.themes[netdataTheme];
-    else
-        NETDATA.themes.current = NETDATA.themes.white;
-
-    NETDATA.colors = NETDATA.themes.current.colors;
-
-    // these are the colors Google Charts are using
-    // we have them here to attempt emulate their look and feel on the other chart libraries
-    // http://there4.io/2012/05/02/google-chart-color-list/
-    //NETDATA.colors        = [ '#3366CC', '#DC3912', '#FF9900', '#109618', '#990099', '#3B3EAC', '#0099C6',
-    //                      '#DD4477', '#66AA00', '#B82E2E', '#316395', '#994499', '#22AA99', '#AAAA11',
-    //                      '#6633CC', '#E67300', '#8B0707', '#329262', '#5574A6', '#3B3EAC' ];
-
-    // an alternative set
-    // http://www.mulinblog.com/a-color-palette-optimized-for-data-visualization/
-    //                         (blue)     (red)      (orange)   (green)    (pink)     (brown)    (purple)   (yellow)   (gray)
-    //NETDATA.colors        = [ '#5DA5DA', '#F15854', '#FAA43A', '#60BD68', '#F17CB0', '#B2912F', '#B276B2', '#DECF3F', '#4D4D4D' ];
-
-    NETDATA.icons = {
-        left: '<i class="fas fa-backward"></i>',
-        reset: '<i class="fas fa-play"></i>',
-        right: '<i class="fas fa-forward"></i>',
-        zoomIn: '<i class="fas fa-plus"></i>',
-        zoomOut: '<i class="fas fa-minus"></i>',
-        resize: '<i class="fas fa-sort"></i>',
-        lineChart: '<i class="fas fa-chart-line"></i>',
-        areaChart: '<i class="fas fa-chart-area"></i>',
-        noChart: '<i class="fas fa-chart-area"></i>',
-        loading: '<i class="fas fa-sync-alt"></i>',
-        noData: '<i class="fas fa-exclamation-triangle"></i>'
-    };
+    if (typeof(value) === 'string') {
+        if (value === 'yes' || value === 'on') {
+            return true;
+        }
 
-    if(typeof netdataIcons === 'object') {
-        for(var icon in NETDATA.icons) {
-            if(NETDATA.icons.hasOwnProperty(icon) && typeof(netdataIcons[icon]) === 'string')
-                NETDATA.icons[icon] = netdataIcons[icon];
+        if (value === '' || value === 'no' || value === 'off' || value === 'null') {
+            return false;
         }
+
+        return def;
     }
 
-    if(typeof netdataSnapshotData === 'undefined')
-        netdataSnapshotData = null;
+    if (typeof(value) === 'number') {
+        return value !== 0;
+    }
 
-    if(typeof netdataShowHelp === 'undefined')
-        netdataShowHelp = true;
+    return def;
+};
 
-    if(typeof netdataShowAlarms === 'undefined')
-        netdataShowAlarms = false;
+// ----------------------------------------------------------------------------------------------------------------
+// fast numbers formatting
 
-    if(typeof netdataRegistryAfterMs !== 'number' || netdataRegistryAfterMs < 0)
-        netdataRegistryAfterMs = 1500;
+NETDATA.fastNumberFormat = {
+    formatters_fixed: [],
+    formatters_zero_based: [],
 
-    if(typeof netdataRegistry === 'undefined') {
-        // backward compatibility
-        netdataRegistry = (typeof netdataNoRegistry !== 'undefined' && netdataNoRegistry === false);
-    }
-    if(netdataRegistry === false && typeof netdataRegistryCallback === 'function')
-        netdataRegistry = true;
+    // this is the fastest and the preferred
+    getIntlNumberFormat: function (min, max) {
+        let key = max;
+        if (min === max) {
+            if (typeof this.formatters_fixed[key] === 'undefined') {
+                this.formatters_fixed[key] = new Intl.NumberFormat(undefined, {
+                    // style: 'decimal',
+                    // minimumIntegerDigits: 1,
+                    // minimumSignificantDigits: 1,
+                    // maximumSignificantDigits: 1,
+                    useGrouping: true,
+                    minimumFractionDigits: min,
+                    maximumFractionDigits: max
+                });
+            }
 
+            return this.formatters_fixed[key];
+        } else if (min === 0) {
+            if (typeof this.formatters_zero_based[key] === 'undefined') {
+                this.formatters_zero_based[key] = new Intl.NumberFormat(undefined, {
+                    // style: 'decimal',
+                    // minimumIntegerDigits: 1,
+                    // minimumSignificantDigits: 1,
+                    // maximumSignificantDigits: 1,
+                    useGrouping: true,
+                    minimumFractionDigits: min,
+                    maximumFractionDigits: max
+                });
+            }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // detect if this is probably a slow device
+            return this.formatters_zero_based[key];
+        } else {
+            // this is never used
+            // it is added just for completeness
+            return new Intl.NumberFormat(undefined, {
+                // style: 'decimal',
+                // minimumIntegerDigits: 1,
+                // minimumSignificantDigits: 1,
+                // maximumSignificantDigits: 1,
+                useGrouping: true,
+                minimumFractionDigits: min,
+                maximumFractionDigits: max
+            });
+        }
+    },
 
-    var isSlowDeviceResult = undefined;
-    var isSlowDevice = function() {
-        if(isSlowDeviceResult !== undefined)
-            return isSlowDeviceResult;
+    // this respects locale
+    getLocaleString: function (min, max) {
+        let key = max;
+        if (min === max) {
+            if (typeof this.formatters_fixed[key] === 'undefined') {
+                this.formatters_fixed[key] = {
+                    format: function (value) {
+                        return value.toLocaleString(undefined, {
+                            // style: 'decimal',
+                            // minimumIntegerDigits: 1,
+                            // minimumSignificantDigits: 1,
+                            // maximumSignificantDigits: 1,
+                            useGrouping: true,
+                            minimumFractionDigits: min,
+                            maximumFractionDigits: max
+                        });
+                    }
+                };
+            }
 
-        try {
-            var ua = navigator.userAgent.toLowerCase();
+            return this.formatters_fixed[key];
+        } else if (min === 0) {
+            if (typeof this.formatters_zero_based[key] === 'undefined') {
+                this.formatters_zero_based[key] = {
+                    format: function (value) {
+                        return value.toLocaleString(undefined, {
+                            // style: 'decimal',
+                            // minimumIntegerDigits: 1,
+                            // minimumSignificantDigits: 1,
+                            // maximumSignificantDigits: 1,
+                            useGrouping: true,
+                            minimumFractionDigits: min,
+                            maximumFractionDigits: max
+                        });
+                    }
+                };
+            }
 
-            var iOS = /ipad|iphone|ipod/.test(ua) && !window.MSStream;
-            var android = /android/.test(ua) && !window.MSStream;
-            isSlowDeviceResult = (iOS === true || android === true);
-        }
-        catch (e) {
-            isSlowDeviceResult = false;
+            return this.formatters_zero_based[key];
+        } else {
+            return {
+                format: function (value) {
+                    return value.toLocaleString(undefined, {
+                        // style: 'decimal',
+                        // minimumIntegerDigits: 1,
+                        // minimumSignificantDigits: 1,
+                        // maximumSignificantDigits: 1,
+                        useGrouping: true,
+                        minimumFractionDigits: min,
+                        maximumFractionDigits: max
+                    });
+                }
+            };
         }
+    },
 
-        return isSlowDeviceResult;
-    };
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // the defaults for all charts
-
-    // if the user does not specify any of these, the following will be used
-
-    NETDATA.chartDefaults = {
-        width: '100%',                  // the chart width - can be null
-        height: '100%',                 // the chart height - can be null
-        min_width: null,                // the chart minimum width - can be null
-        library: 'dygraph',             // the graphing library to use
-        method: 'average',              // the grouping method
-        before: 0,                      // panning
-        after: -600,                    // panning
-        pixels_per_point: 1,            // the detail of the chart
-        fill_luminance: 0.8             // luminance of colors in solid areas
-    };
+    // the fallback
+    getFixed: function (min, max) {
+        let key = max;
+        if (min === max) {
+            if (typeof this.formatters_fixed[key] === 'undefined') {
+                this.formatters_fixed[key] = {
+                    format: function (value) {
+                        if (value === 0) {
+                            return "0";
+                        }
+                        return value.toFixed(max);
+                    }
+                };
+            }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // global options
+            return this.formatters_fixed[key];
+        } else if (min === 0) {
+            if (typeof this.formatters_zero_based[key] === 'undefined') {
+                this.formatters_zero_based[key] = {
+                    format: function (value) {
+                        if (value === 0) {
+                            return "0";
+                        }
+                        return value.toFixed(max);
+                    }
+                };
+            }
 
-    NETDATA.options = {
-        pauseCallback: null,            // a callback when we are really paused
+            return this.formatters_zero_based[key];
+        } else {
+            return {
+                format: function (value) {
+                    if (value === 0) {
+                        return "0";
+                    }
+                    return value.toFixed(max);
+                }
+            };
+        }
+    },
 
-        pause: false,                   // when enabled we don't auto-refresh the charts
+    testIntlNumberFormat: function () {
+        let value = 1.12345;
+        let e1 = "1.12", e2 = "1,12";
+        let s = "";
 
-        targets: [],                    // an array of all the state objects that are
-                                        // currently active (independently of their
-                                        // viewport visibility)
+        try {
+            let x = new Intl.NumberFormat(undefined, {
+                useGrouping: true,
+                minimumFractionDigits: 2,
+                maximumFractionDigits: 2
+            });
 
-        updated_dom: true,              // when true, the DOM has been updated with
-                                        // new elements we have to check.
+            s = x.format(value);
+        } catch (e) {
+            s = "";
+        }
 
-        auto_refresher_fast_weight: 0,  // this is the current time in ms, spent
-                                        // rendering charts continuously.
-                                        // used with .current.fast_render_timeframe
+        // console.log('NumberFormat: ', s);
+        return (s === e1 || s === e2);
+    },
 
-        page_is_visible: true,          // when true, this page is visible
+    testLocaleString: function () {
+        let value = 1.12345;
+        let e1 = "1.12", e2 = "1,12";
+        let s = "";
 
-        auto_refresher_stop_until: 0,   // timestamp in ms - used internally, to stop the
-                                        // auto-refresher for some time (when a chart is
-                                        // performing pan or zoom, we need to stop refreshing
-                                        // all other charts, to have the maximum speed for
-                                        // rendering the chart that is panned or zoomed).
-                                        // Used with .current.global_pan_sync_time
+        try {
+            s = value.toLocaleString(undefined, {
+                useGrouping: true,
+                minimumFractionDigits: 2,
+                maximumFractionDigits: 2
+            });
+        } catch (e) {
+            s = "";
+        }
+
+        // console.log('localeString: ', s);
+        return (s === e1 || s === e2);
+    },
+
+    // on first run we decide which formatter to use
+    get: function (min, max) {
+        if (this.testIntlNumberFormat()) {
+            // console.log('numberformat');
+            this.get = this.getIntlNumberFormat;
+        } else if (this.testLocaleString()) {
+            // console.log('localestring');
+            this.get = this.getLocaleString;
+        } else {
+            // console.log('fixed');
+            this.get = this.getFixed;
+        }
+        return this.get(min, max);
+    }
+};
+// Error Handling
+
+NETDATA.errorCodes = {
+    100: {message: "Cannot load chart library", alert: true},
+    101: {message: "Cannot load jQuery", alert: true},
+    402: {message: "Chart library not found", alert: false},
+    403: {message: "Chart library not enabled/is failed", alert: false},
+    404: {message: "Chart not found", alert: false},
+    405: {message: "Cannot download charts index from server", alert: true},
+    406: {message: "Invalid charts index downloaded from server", alert: true},
+    407: {message: "Cannot HELLO netdata server", alert: false},
+    408: {message: "Netdata servers sent invalid response to HELLO", alert: false},
+    409: {message: "Cannot ACCESS netdata registry", alert: false},
+    410: {message: "Netdata registry ACCESS failed", alert: false},
+    411: {message: "Netdata registry server send invalid response to DELETE ", alert: false},
+    412: {message: "Netdata registry DELETE failed", alert: false},
+    413: {message: "Netdata registry server send invalid response to SWITCH ", alert: false},
+    414: {message: "Netdata registry SWITCH failed", alert: false},
+    415: {message: "Netdata alarms download failed", alert: false},
+    416: {message: "Netdata alarms log download failed", alert: false},
+    417: {message: "Netdata registry server send invalid response to SEARCH ", alert: false},
+    418: {message: "Netdata registry SEARCH failed", alert: false}
+};
+
+NETDATA.errorLast = {
+    code: 0,
+    message: "",
+    datetime: 0
+};
+
+NETDATA.error = function (code, msg) {
+    NETDATA.errorLast.code = code;
+    NETDATA.errorLast.message = msg;
+    NETDATA.errorLast.datetime = Date.now();
+
+    console.log("ERROR " + code + ": " + NETDATA.errorCodes[code].message + ": " + msg);
+
+    let ret = true;
+    if (typeof netdataErrorCallback === 'function') {
+        ret = netdataErrorCallback('system', code, msg);
+    }
 
-        on_scroll_refresher_stop_until: 0, // timestamp in ms - used to stop evaluating
-                                        // charts for some time, after a page scroll
+    if (ret && NETDATA.errorCodes[code].alert) {
+        alert("ERROR " + code + ": " + NETDATA.errorCodes[code].message + ": " + msg);
+    }
+};
 
-        last_page_resize: Date.now(),   // the timestamp of the last resize request
+NETDATA.errorReset = function () {
+    NETDATA.errorLast.code = 0;
+    NETDATA.errorLast.message = "You are doing fine!";
+    NETDATA.errorLast.datetime = 0;
+};
+// ------------------------------------------------------------------------
+// compatibility fixes
 
-        last_page_scroll: 0,            // the timestamp the last time the page was scrolled
+// fix IE issue with console
+if (!window.console) {
+    window.console = {
+        log: function () {
+        }
+    };
+}
 
-        browser_timezone: 'unknown',    // timezone detected by javascript
-        server_timezone: 'unknown',     // timezone reported by the server
+// if string.endsWith is not defined, define it
+if (typeof String.prototype.endsWith !== 'function') {
+    String.prototype.endsWith = function (s) {
+        if (s.length > this.length) {
+            return false;
+        }
+        return this.slice(-s.length) === s;
+    };
+}
 
-        force_data_points: 0,           // force the number of points to be returned for charts
-        fake_chart_rendering: false,    // when set to true, the dashboard will download data but will not render the charts
+// if string.startsWith is not defined, define it
+if (typeof String.prototype.startsWith !== 'function') {
+    String.prototype.startsWith = function (s) {
+        if (s.length > this.length) {
+            return false;
+        }
+        return this.slice(s.length) === s;
+    };
+}
+
+NETDATA.name2id = function (s) {
+    return s
+        .replace(/ /g, '_')
+        .replace(/\(/g, '_')
+        .replace(/\)/g, '_')
+        .replace(/\./g, '_')
+        .replace(/\//g, '_');
+};
+// ----------------------------------------------------------------------------------------------------------------
+// XSS checks
+
+NETDATA.xss = {
+    enabled: (typeof netdataCheckXSS === 'undefined') ? false : netdataCheckXSS,
+    enabled_for_data: (typeof netdataCheckXSS === 'undefined') ? false : netdataCheckXSS,
+
+    string: function (s) {
+        return s.toString()
+            .replace(/</g, '&lt;')
+            .replace(/>/g, '&gt;')
+            .replace(/"/g, '&quot;')
+            .replace(/'/g, '&#39;');
+    },
+
+    object: function (name, obj, ignore_regex) {
+        if (typeof ignore_regex !== 'undefined' && ignore_regex.test(name)) {
+            // console.log('XSS: ignoring "' + name + '"');
+            return obj;
+        }
 
-        passive_events: null,           // true if the browser supports passive events
+        switch (typeof(obj)) {
+            case 'string':
+                const ret = this.string(obj);
+                if (ret !== obj) {
+                    console.log('XSS protection changed string ' + name + ' from "' + obj + '" to "' + ret + '"');
+                }
+                return ret;
 
-        // the current profile
-        // we may have many...
-        current: {
-            units: 'auto',              // can be 'auto' or 'original'
-            temperature: 'celsius',     // can be 'celsius' or 'fahrenheit'
-            seconds_as_time: true,      // show seconds as DDd:HH:MM:SS ?
-            timezone: 'default',        // the timezone to use, or 'default'
-            user_set_server_timezone: 'default', // as set by the user on the dashboard
+            case 'object':
+                if (obj === null) {
+                    return obj;
+                }
 
-            legend_toolbox: true,       // show the legend toolbox on charts
-            resize_charts: true,        // show the resize handler on charts
+                if (Array.isArray(obj)) {
+                    // console.log('checking array "' + name + '"');
 
-            pixels_per_point: isSlowDevice()?5:1, // the minimum pixels per point for all charts
-                                        // increase this to speed javascript up
-                                        // each chart library has its own limit too
-                                        // the max of this and the chart library is used
-                                        // the final is calculated every time, so a change
-                                        // here will have immediate effect on the next chart
-                                        // update
+                    let len = obj.length;
+                    while (len--) {
+                        obj[len] = this.object(name + '[' + len + ']', obj[len], ignore_regex);
+                    }
+                } else {
+                    // console.log('checking object "' + name + '"');
 
-            idle_between_charts: 100,   // ms - how much time to wait between chart updates
+                    for (const i in obj) {
+                        if (obj.hasOwnProperty(i) === false) {
+                            continue;
+                        }
+                        if (this.string(i) !== i) {
+                            console.log('XSS protection removed invalid object member "' + name + '.' + i + '"');
+                            delete obj[i];
+                        } else {
+                            obj[i] = this.object(name + '.' + i, obj[i], ignore_regex);
+                        }
+                    }
+                }
+                return obj;
 
-            fast_render_timeframe: 200, // ms - render continuously until this time of continuous
-                                        // rendering has been reached
-                                        // this setting is used to make it render e.g. 10
-                                        // charts at once, sleep idle_between_charts time
-                                        // and continue for another 10 charts.
+            default:
+                return obj;
+        }
+    },
 
-            idle_between_loops: 500,    // ms - if all charts have been updated, wait this
-                                        // time before starting again.
+    checkOptional: function (name, obj, ignore_regex) {
+        if (this.enabled) {
+            //console.log('XSS: checking optional "' + name + '"...');
+            return this.object(name, obj, ignore_regex);
+        }
+        return obj;
+    },
 
-            idle_parallel_loops: 100,   // ms - the time between parallel refresher updates
+    checkAlways: function (name, obj, ignore_regex) {
+        //console.log('XSS: checking always "' + name + '"...');
+        return this.object(name, obj, ignore_regex);
+    },
 
-            idle_lost_focus: 500,       // ms - when the window does not have focus, check
-                                        // if focus has been regained, every this time
+    checkData: function (name, obj, ignore_regex) {
+        if (this.enabled_for_data) {
+            //console.log('XSS: checking data "' + name + '"...');
+            return this.object(name, obj, ignore_regex);
+        }
+        return obj;
+    }
+};
+NETDATA.colorHex2Rgb = function (hex) {
+    // Expand shorthand form (e.g. "03F") to full form (e.g. "0033FF")
+    let shorthandRegex = /^#?([a-f\d])([a-f\d])([a-f\d])$/i;
+    hex = hex.replace(shorthandRegex, function (m, r, g, b) {
+        return r + r + g + g + b + b;
+    });
 
-            global_pan_sync_time: 300,  // ms - when you pan or zoom a chart, the background
-                                        // auto-refreshing of charts is paused for this amount
-                                        // of time
+    let result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
+    return result ? {
+        r: parseInt(result[1], 16),
+        g: parseInt(result[2], 16),
+        b: parseInt(result[3], 16)
+    } : null;
+};
+
+NETDATA.colorLuminance = function (hex, lum) {
+    // validate hex string
+    hex = String(hex).replace(/[^0-9a-f]/gi, '');
+    if (hex.length < 6) {
+        hex = hex[0] + hex[0] + hex[1] + hex[1] + hex[2] + hex[2];
+    }
 
-            sync_selection_delay: 400,  // ms - when you pan or zoom a chart, wait this amount
-                                        // of time before setting up synchronized selections
-                                        // on hover.
+    lum = lum || 0;
 
-            sync_selection: true,       // enable or disable selection sync
+    // convert to decimal and change luminosity
+    let rgb = "#";
+    for (let i = 0; i < 3; i++) {
+        let c = parseInt(hex.substr(i * 2, 2), 16);
+        c = Math.round(Math.min(Math.max(0, c + (c * lum)), 255)).toString(16);
+        rgb += ("00" + c).substr(c.length);
+    }
 
-            pan_and_zoom_delay: 50,     // when panning or zooming, how ofter to update the chart
+    return rgb;
+};
+NETDATA.unitsConversion = {
+    keys: {},       // keys for data-common-units
+    latest: {},     // latest selected units for data-common-units
+
+    globalReset: function () {
+        this.keys = {};
+        this.latest = {};
+    },
+
+    scalableUnits: {
+        'packets/s': {
+            'pps': 1,
+            'Kpps': 1000,
+            'Mpps': 1000000
+        },
+        'pps': {
+            'pps': 1,
+            'Kpps': 1000,
+            'Mpps': 1000000
+        },
+        'kilobits/s': {
+            'bits/s': 1 / 1000,
+            'kilobits/s': 1,
+            'megabits/s': 1000,
+            'gigabits/s': 1000000,
+            'terabits/s': 1000000000
+        },
+        'kilobytes/s': {
+            'bytes/s': 1 / 1024,
+            'kilobytes/s': 1,
+            'megabytes/s': 1024,
+            'gigabytes/s': 1024 * 1024,
+            'terabytes/s': 1024 * 1024 * 1024
+        },
+        'KB/s': {
+            'B/s': 1 / 1024,
+            'KB/s': 1,
+            'MB/s': 1024,
+            'GB/s': 1024 * 1024,
+            'TB/s': 1024 * 1024 * 1024
+        },
+        'KB': {
+            'B': 1 / 1024,
+            'KB': 1,
+            'MB': 1024,
+            'GB': 1024 * 1024,
+            'TB': 1024 * 1024 * 1024
+        },
+        'MB': {
+            'B': 1 / (1024 * 1024),
+            'KB': 1 / 1024,
+            'MB': 1,
+            'GB': 1024,
+            'TB': 1024 * 1024,
+            'PB': 1024 * 1024 * 1024
+        },
+        'GB': {
+            'B': 1 / (1024 * 1024 * 1024),
+            'KB': 1 / (1024 * 1024),
+            'MB': 1 / 1024,
+            'GB': 1,
+            'TB': 1024,
+            'PB': 1024 * 1024,
+            'EB': 1024 * 1024 * 1024
+        }
+        /*
+        'milliseconds': {
+            'seconds': 1000
+        },
+        'seconds': {
+            'milliseconds': 0.001,
+            'seconds': 1,
+            'minutes': 60,
+            'hours': 3600,
+            'days': 86400
+        }
+        */
+    },
+
+    convertibleUnits: {
+        'Celsius': {
+            'Fahrenheit': {
+                check: function (max) {
+                    void(max);
+                    return NETDATA.options.current.temperature === 'fahrenheit';
+                },
+                convert: function (value) {
+                    return value * 9 / 5 + 32;
+                }
+            }
+        },
+        'celsius': {
+            'fahrenheit': {
+                check: function (max) {
+                    void(max);
+                    return NETDATA.options.current.temperature === 'fahrenheit';
+                },
+                convert: function (value) {
+                    return value * 9 / 5 + 32;
+                }
+            }
+        },
+        'seconds': {
+            'time': {
+                check: function (max) {
+                    void(max);
+                    return NETDATA.options.current.seconds_as_time;
+                },
+                convert: function (seconds) {
+                    return NETDATA.unitsConversion.seconds2time(seconds);
+                }
+            }
+        },
+        'milliseconds': {
+            'milliseconds': {
+                check: function (max) {
+                    return NETDATA.options.current.seconds_as_time && max < 1000;
+                },
+                convert: function (milliseconds) {
+                    let tms = Math.round(milliseconds * 10);
+                    milliseconds = Math.floor(tms / 10);
 
-            sync_pan_and_zoom: true,    // enable or disable pan and zoom sync
+                    tms -= milliseconds * 10;
 
-            pan_and_zoom_data_padding: true, // fetch more data for the master chart when panning or zooming
+                    return (milliseconds).toString() + '.' + tms.toString();
+                }
+            },
+            'seconds': {
+                check: function (max) {
+                    return NETDATA.options.current.seconds_as_time && max >= 1000 && max < 60000;
+                },
+                convert: function (milliseconds) {
+                    milliseconds = Math.round(milliseconds);
 
-            update_only_visible: true,  // enable or disable visibility management / used for printing
+                    let seconds = Math.floor(milliseconds / 1000);
+                    milliseconds -= seconds * 1000;
 
-            parallel_refresher: (isSlowDevice() === false), // enable parallel refresh of charts
+                    milliseconds = Math.round(milliseconds / 10);
 
-            concurrent_refreshes: true, // when parallel_refresher is enabled, sync also the charts
+                    return seconds.toString() + '.'
+                        + NETDATA.zeropad(milliseconds);
+                }
+            },
+            'M:SS.ms': {
+                check: function (max) {
+                    return NETDATA.options.current.seconds_as_time && max >= 60000;
+                },
+                convert: function (milliseconds) {
+                    milliseconds = Math.round(milliseconds);
 
-            destroy_on_hide: (isSlowDevice() === true), // destroy charts when they are not visible
+                    let minutes = Math.floor(milliseconds / 60000);
+                    milliseconds -= minutes * 60000;
 
-            show_help: netdataShowHelp, // when enabled the charts will show some help
-            show_help_delay_show_ms: 500,
-            show_help_delay_hide_ms: 0,
+                    let seconds = Math.floor(milliseconds / 1000);
+                    milliseconds -= seconds * 1000;
 
-            eliminate_zero_dimensions: true, // do not show dimensions with just zeros
+                    milliseconds = Math.round(milliseconds / 10);
 
-            stop_updates_when_focus_is_lost: true, // boolean - shall we stop auto-refreshes when document does not have user focus
-            stop_updates_while_resizing: 1000,  // ms - time to stop auto-refreshes while resizing the charts
+                    return minutes.toString() + ':'
+                        + NETDATA.zeropad(seconds) + '.'
+                        + NETDATA.zeropad(milliseconds);
+                }
+            }
+        }
+    },
 
-            double_click_speed: 500,    // ms - time between clicks / taps to detect double click/tap
+    seconds2time: function (seconds) {
+        seconds = Math.abs(seconds);
 
-            smooth_plot: (isSlowDevice() === false), // enable smooth plot, where possible
+        let days = Math.floor(seconds / 86400);
+        seconds -= days * 86400;
 
-            color_fill_opacity_line: 1.0,
-            color_fill_opacity_area: 0.2,
-            color_fill_opacity_stacked: 0.8,
+        let hours = Math.floor(seconds / 3600);
+        seconds -= hours * 3600;
 
-            pan_and_zoom_factor: 0.25,      // the increment when panning and zooming with the toolbox
-            pan_and_zoom_factor_multiplier_control: 2.0,
-            pan_and_zoom_factor_multiplier_shift: 3.0,
-            pan_and_zoom_factor_multiplier_alt: 4.0,
+        let minutes = Math.floor(seconds / 60);
+        seconds -= minutes * 60;
 
-            abort_ajax_on_scroll: false,            // kill pending ajax page scroll
-            async_on_scroll: false,                 // sync/async onscroll handler
-            onscroll_worker_duration_threshold: 30, // time in ms, for async scroll handler
+        seconds = Math.round(seconds);
 
-            retries_on_data_failures: 3, // how many retries to make if we can't fetch chart data from the server
+        let ms_txt = '';
+        /*
+        let ms = seconds - Math.floor(seconds);
+        seconds -= ms;
+        ms = Math.round(ms * 1000);
 
-            setOptionCallback: function() { }
-        },
+        if (ms > 1) {
+            if (ms < 10)
+                ms_txt = '.00' + ms.toString();
+            else if (ms < 100)
+                ms_txt = '.0' + ms.toString();
+            else
+                ms_txt = '.' + ms.toString();
+        }
+        */
+
+        return ((days > 0) ? days.toString() + 'd:' : '').toString()
+            + NETDATA.zeropad(hours) + ':'
+            + NETDATA.zeropad(minutes) + ':'
+            + NETDATA.zeropad(seconds)
+            + ms_txt;
+    },
+
+    // get a function that converts the units
+    // + every time units are switched call the callback
+    get: function (uuid, min, max, units, desired_units, common_units_name, switch_units_callback) {
+        // validate the parameters
+        if (typeof units === 'undefined') {
+            units = 'undefined';
+        }
+
+        // check if we support units conversion
+        if (typeof this.scalableUnits[units] === 'undefined' && typeof this.convertibleUnits[units] === 'undefined') {
+            // we can't convert these units
+            //console.log('DEBUG: ' + uuid.toString() + ' can\'t convert units: ' + units.toString());
+            return function (value) {
+                return value;
+            };
+        }
 
-        debug: {
-            show_boxes:         false,
-            main_loop:          false,
-            focus:              false,
-            visibility:         false,
-            chart_data_url:     false,
-            chart_errors:       false, // remember to set it to false before merging
-            chart_timing:       false,
-            chart_calls:        false,
-            libraries:          false,
-            dygraph:            false,
-            globalSelectionSync:false,
-            globalPanAndZoom:   false
+        // check if the caller wants the original units
+        if (typeof desired_units === 'undefined' || desired_units === null || desired_units === 'original' || desired_units === units) {
+            //console.log('DEBUG: ' + uuid.toString() + ' original units wanted');
+            switch_units_callback(units);
+            return function (value) {
+                return value;
+            };
         }
-    };
 
-    NETDATA.statistics = {
-        refreshes_total: 0,
-        refreshes_active: 0,
-        refreshes_active_max: 0
-    };
+        // now we know we can convert the units
+        // and the caller wants some kind of conversion
 
+        let tunits = null;
+        let tdivider = 0;
 
-    // ----------------------------------------------------------------------------------------------------------------
+        if (typeof this.scalableUnits[units] !== 'undefined') {
+            // units that can be scaled
+            // we decide a divider
 
-    NETDATA.timeout = {
-        // by default, these are just wrappers to setTimeout() / clearTimeout()
+            // console.log('NETDATA.unitsConversion.get(' + units.toString() + ', ' + desired_units.toString() + ', function()) decide divider with min = ' + min.toString() + ', max = ' + max.toString());
 
-        step: function(callback) {
-            return window.setTimeout(callback, 1000 / 60);
-        },
+            if (desired_units === 'auto') {
+                // the caller wants to auto-scale the units
 
-        set: function(callback, delay) {
-            return window.setTimeout(callback, delay);
-        },
+                // find the absolute maximum value that is rendered on the chart
+                // based on this we decide the scale
+                min = Math.abs(min);
+                max = Math.abs(max);
+                if (min > max) {
+                    max = min;
+                }
 
-        clear: function(id) {
-            return window.clearTimeout(id);
-        },
+                // find the smallest scale that provides integers
+                // for (x in this.scalableUnits[units]) {
+                //     if (this.scalableUnits[units].hasOwnProperty(x)) {
+                //         let m = this.scalableUnits[units][x];
+                //         if (m <= max && m > tdivider) {
+                //             tunits = x;
+                //             tdivider = m;
+                //         }
+                //     }
+                // }
+                const sunit = this.scalableUnits[units];
+                for (const x of Object.keys(sunit)) {
+                    let m = sunit[x];
+                    if (m <= max && m > tdivider) {
+                        tunits = x;
+                        tdivider = m;
+                    }
+                }
 
-        init: function() {
-            var custom = true;
+                if (tunits === null || tdivider <= 0) {
+                    // we couldn't find one
+                    //console.log('DEBUG: ' + uuid.toString() + ' cannot find an auto-scaling candidate for units: ' + units.toString() + ' (max: ' + max.toString() + ')');
+                    switch_units_callback(units);
+                    return function (value) {
+                        return value;
+                    };
+                }
 
-            if(window.requestAnimationFrame) {
-                this.step = function(callback) {
-                    return window.requestAnimationFrame(callback);
-                };
+                if (typeof common_units_name === 'string' && typeof uuid === 'string') {
+                    // the caller wants several charts to have the same units
+                    // data-common-units
 
-                this.clear = function(handle) {
-                    return window.cancelAnimationFrame(handle.value);
-                };
-            }
-            else if(window.webkitRequestAnimationFrame) {
-                this.step = function(callback) {
-                    return window.webkitRequestAnimationFrame(callback);
-                };
+                    let common_units_key = common_units_name + '-' + units;
 
-                if(window.webkitCancelAnimationFrame) {
-                    this.clear = function (handle) {
-                        return window.webkitCancelAnimationFrame(handle.value);
-                    };
-                }
-                else if(window.webkitCancelRequestAnimationFrame) {
-                    this.clear = function (handle) {
-                        return window.webkitCancelRequestAnimationFrame(handle.value);
+                    // add our divider into the list of keys
+                    let t = this.keys[common_units_key];
+                    if (typeof t === 'undefined') {
+                        this.keys[common_units_key] = {};
+                        t = this.keys[common_units_key];
+                    }
+                    t[uuid] = {
+                        units: tunits,
+                        divider: tdivider
                     };
-                }
-            }
-            else if(window.mozRequestAnimationFrame) {
-                this.step = function(callback) {
-                    return window.mozRequestAnimationFrame(callback);
-                };
 
-                this.clear = function(handle) {
-                    return window.mozCancelRequestAnimationFrame(handle.value);
-                };
-            }
-            else if(window.oRequestAnimationFrame) {
-                this.step = function(callback) {
-                    return window.oRequestAnimationFrame(callback);
-                };
-
-                this.clear = function(handle) {
-                    return window.oCancelRequestAnimationFrame(handle.value);
-                };
-            }
-            else if(window.msRequestAnimationFrame) {
-                this.step = function(callback) {
-                    return window.msRequestAnimationFrame(callback);
-                };
-
-                this.clear = function(handle) {
-                    return window.msCancelRequestAnimationFrame(handle.value);
-                };
-            }
-            else
-                custom = false;
-
-
-            if(custom === true) {
-                // we have installed custom .step() / .clear() functions
-                // overwrite the .set() too
-
-                this.set = function(callback, delay) {
-                    var that = this;
+                    // find the max divider of all charts
+                    let common_units = t[uuid];
+                    for (const x in t) {
+                        if (t.hasOwnProperty(x) && t[x].divider > common_units.divider) {
+                            common_units = t[x];
+                        }
+                    }
 
-                    var start = Date.now(),
-                        handle = new Object();
+                    // save our common_max to the latest keys
+                    let latest = this.latest[common_units_key];
+                    if (typeof latest === 'undefined') {
+                        this.latest[common_units_key] = {};
+                        latest = this.latest[common_units_key];
+                    }
+                    latest.units = common_units.units;
+                    latest.divider = common_units.divider;
+
+                    tunits = latest.units;
+                    tdivider = latest.divider;
+
+                    //console.log('DEBUG: ' + uuid.toString() + ' converted units: ' + units.toString() + ' to units: ' + tunits.toString() + ' with divider ' + tdivider.toString() + ', common-units=' + common_units_name.toString() + ((t[uuid].divider !== tdivider)?' USED COMMON, mine was ' + t[uuid].units:' set common').toString());
+
+                    // apply it to this chart
+                    switch_units_callback(tunits);
+                    return function (value) {
+                        if (tdivider !== latest.divider) {
+                            // another chart switched our common units
+                            // we should switch them too
+                            //console.log('DEBUG: ' + uuid + ' switching units due to a common-units change, from ' + tunits.toString() + ' to ' + latest.units.toString());
+                            tunits = latest.units;
+                            tdivider = latest.divider;
+                            switch_units_callback(tunits);
+                        }
 
-                    function loop() {
-                        var current = Date.now(),
-                            delta = current - start;
+                        return value / tdivider;
+                    };
+                } else {
+                    // the caller did not give data-common-units
+                    // this chart auto-scales independently of all others
+                    //console.log('DEBUG: ' + uuid.toString() + ' converted units: ' + units.toString() + ' to units: ' + tunits.toString() + ' with divider ' + tdivider.toString() + ', autonomously');
+
+                    switch_units_callback(tunits);
+                    return function (value) {
+                        return value / tdivider;
+                    };
+                }
+            } else {
+                // the caller wants specific units
 
-                        if(delta >= delay) {
-                            callback.call();
-                        }
-                        else {
-                            handle.value = that.step(loop);
+                if (typeof this.scalableUnits[units][desired_units] !== 'undefined') {
+                    // all good, set the new units
+                    tdivider = this.scalableUnits[units][desired_units];
+                    // console.log('DEBUG: ' + uuid.toString() + ' converted units: ' + units.toString() + ' to units: ' + desired_units.toString() + ' with divider ' + tdivider.toString() + ', by reference');
+                    switch_units_callback(desired_units);
+                    return function (value) {
+                        return value / tdivider;
+                    };
+                } else {
+                    // oops! switch back to original units
+                    console.log('Units conversion from ' + units.toString() + ' to ' + desired_units.toString() + ' is not supported.');
+                    switch_units_callback(units);
+                    return function (value) {
+                        return value;
+                    };
+                }
+            }
+        } else if (typeof this.convertibleUnits[units] !== 'undefined') {
+            // units that can be converted
+            if (desired_units === 'auto') {
+                for (const x in this.convertibleUnits[units]) {
+                    if (this.convertibleUnits[units].hasOwnProperty(x)) {
+                        if (this.convertibleUnits[units][x].check(max)) {
+                            //console.log('DEBUG: ' + uuid.toString() + ' converting ' + units.toString() + ' to: ' + x.toString());
+                            switch_units_callback(x);
+                            return this.convertibleUnits[units][x].convert;
                         }
                     }
+                }
 
-                    handle.value = that.step(loop);
-                    return handle;
+                // none checked ok
+                //console.log('DEBUG: ' + uuid.toString() + ' no conversion available for ' + units.toString() + ' to: ' + desired_units.toString());
+                switch_units_callback(units);
+                return function (value) {
+                    return value;
+                };
+            } else if (typeof this.convertibleUnits[units][desired_units] !== 'undefined') {
+                switch_units_callback(desired_units);
+                return this.convertibleUnits[units][desired_units].convert;
+            } else {
+                console.log('Units conversion from ' + units.toString() + ' to ' + desired_units.toString() + ' is not supported.');
+                switch_units_callback(units);
+                return function (value) {
+                    return value;
                 };
             }
+        } else {
+            // hm... did we forget to implement the new type?
+            console.log(`Unmatched unit conversion method for units ${units.toString()}`);
+            switch_units_callback(units);
+            return function (value) {
+                return value;
+            };
         }
-    };
-
-    NETDATA.timeout.init();
-
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // local storage options
-
-    NETDATA.localStorage = {
-        default: {},
-        current: {},
-        callback: {} // only used for resetting back to defaults
-    };
-
-    NETDATA.localStorageTested = -1;
-    NETDATA.localStorageTest = function() {
-        if(NETDATA.localStorageTested !== -1)
-            return NETDATA.localStorageTested;
-
-        if(typeof Storage !== "undefined" && typeof localStorage === 'object') {
-            var test = 'test';
-            try {
-                localStorage.setItem(test, test);
-                localStorage.removeItem(test);
-                NETDATA.localStorageTested = true;
-            }
-            catch (e) {
-                NETDATA.localStorageTested = false;
-            }
+    }
+};
+
+NETDATA.icons = {
+    left: '<i class="fas fa-backward"></i>',
+    reset: '<i class="fas fa-play"></i>',
+    right: '<i class="fas fa-forward"></i>',
+    zoomIn: '<i class="fas fa-plus"></i>',
+    zoomOut: '<i class="fas fa-minus"></i>',
+    resize: '<i class="fas fa-sort"></i>',
+    lineChart: '<i class="fas fa-chart-line"></i>',
+    areaChart: '<i class="fas fa-chart-area"></i>',
+    noChart: '<i class="fas fa-chart-area"></i>',
+    loading: '<i class="fas fa-sync-alt"></i>',
+    noData: '<i class="fas fa-exclamation-triangle"></i>'
+};
+
+if (typeof netdataIcons === 'object') {
+    // for (let icon in NETDATA.icons) {
+    //     if (NETDATA.icons.hasOwnProperty(icon) && typeof(netdataIcons[icon]) === 'string')
+    //         NETDATA.icons[icon] = netdataIcons[icon];
+    // }
+    for (const icon of Object.keys(NETDATA.icons)) {
+        if (typeof(netdataIcons[icon]) === 'string') {
+            NETDATA.icons[icon] = netdataIcons[icon]
         }
-        else
-            NETDATA.localStorageTested = false;
-
-        return NETDATA.localStorageTested;
-    };
-
-    NETDATA.localStorageGet = function(key, def, callback) {
-        var ret = def;
+    }
+}
 
-        if(typeof NETDATA.localStorage.default[key.toString()] === 'undefined') {
-            NETDATA.localStorage.default[key.toString()] = def;
-            NETDATA.localStorage.callback[key.toString()] = callback;
-        }
+if (typeof netdataSnapshotData === 'undefined') {
+    netdataSnapshotData = null;
+}
 
-        if(NETDATA.localStorageTest() === true) {
-            try {
-                // console.log('localStorage: loading "' + key.toString() + '"');
-                ret = localStorage.getItem(key.toString());
-                // console.log('netdata loaded: ' + key.toString() + ' = ' + ret.toString());
-                if(ret === null || ret === 'undefined') {
-                    // console.log('localStorage: cannot load it, saving "' + key.toString() + '" with value "' + JSON.stringify(def) + '"');
-                    localStorage.setItem(key.toString(), JSON.stringify(def));
-                    ret = def;
-                }
-                else {
-                    // console.log('localStorage: got "' + key.toString() + '" with value "' + ret + '"');
-                    ret = JSON.parse(ret);
-                    // console.log('localStorage: loaded "' + key.toString() + '" as value ' + ret + ' of type ' + typeof(ret));
-                }
-            }
-            catch(error) {
-                console.log('localStorage: failed to read "' + key.toString() + '", using default: "' + def.toString() + '"');
-                ret = def;
-            }
-        }
+if (typeof netdataShowHelp === 'undefined') {
+    netdataShowHelp = true;
+}
 
-        if(typeof ret === 'undefined' || ret === 'undefined') {
-            console.log('localStorage: LOADED UNDEFINED "' + key.toString() + '" as value ' + ret + ' of type ' + typeof(ret));
-            ret = def;
-        }
+if (typeof netdataShowAlarms === 'undefined') {
+    netdataShowAlarms = false;
+}
 
-        NETDATA.localStorage.current[key.toString()] = ret;
-        return ret;
-    };
+if (typeof netdataRegistryAfterMs !== 'number' || netdataRegistryAfterMs < 0) {
+    netdataRegistryAfterMs = 1500;
+}
 
-    NETDATA.localStorageSet = function(key, value, callback) {
-        if(typeof value === 'undefined' || value === 'undefined') {
-            console.log('localStorage: ATTEMPT TO SET UNDEFINED "' + key.toString() + '" as value ' + value + ' of type ' + typeof(value));
-        }
+if (typeof netdataRegistry === 'undefined') {
+    // backward compatibility
+    netdataRegistry = (typeof netdataNoRegistry !== 'undefined' && netdataNoRegistry === false);
+}
 
-        if(typeof NETDATA.localStorage.default[key.toString()] === 'undefined') {
-            NETDATA.localStorage.default[key.toString()] = value;
-            NETDATA.localStorage.current[key.toString()] = value;
-            NETDATA.localStorage.callback[key.toString()] = callback;
-        }
+if (netdataRegistry === false && typeof netdataRegistryCallback === 'function') {
+    netdataRegistry = true;
+}
 
-        if(NETDATA.localStorageTest() === true) {
-            // console.log('localStorage: saving "' + key.toString() + '" with value "' + JSON.stringify(value) + '"');
-            try {
-                localStorage.setItem(key.toString(), JSON.stringify(value));
-            }
-            catch(e) {
-                console.log('localStorage: failed to save "' + key.toString() + '" with value: "' + value.toString() + '"');
-            }
-        }
+// ----------------------------------------------------------------------------------------------------------------
+// the defaults for all charts
 
-        NETDATA.localStorage.current[key.toString()] = value;
-        return value;
-    };
+// if the user does not specify any of these, the following will be used
 
-    NETDATA.localStorageGetRecursive = function(obj, prefix, callback) {
-        var keys = Object.keys(obj);
-        var len = keys.length;
-        while(len--) {
-            var i = keys[len];
+NETDATA.chartDefaults = {
+    width: '100%',                  // the chart width - can be null
+    height: '100%',                 // the chart height - can be null
+    min_width: null,                // the chart minimum width - can be null
+    library: 'dygraph',             // the graphing library to use
+    method: 'average',              // the grouping method
+    before: 0,                      // panning
+    after: -600,                    // panning
+    pixels_per_point: 1,            // the detail of the chart
+    fill_luminance: 0.8             // luminance of colors in solid areas
+};
 
-            if(typeof obj[i] === 'object') {
-                //console.log('object ' + prefix + '.' + i.toString());
-                NETDATA.localStorageGetRecursive(obj[i], prefix + '.' + i.toString(), callback);
-                continue;
-            }
+// ----------------------------------------------------------------------------------------------------------------
+// global options
 
-            obj[i] = NETDATA.localStorageGet(prefix + '.' + i.toString(), obj[i], callback);
-        }
-    };
+NETDATA.options = {
+    pauseCallback: null,            // a callback when we are really paused
 
-    NETDATA.setOption = function(key, value) {
-        if(key.toString() === 'setOptionCallback') {
-            if(typeof NETDATA.options.current.setOptionCallback === 'function') {
-                NETDATA.options.current[key.toString()] = value;
-                NETDATA.options.current.setOptionCallback();
-            }
-        }
-        else if(NETDATA.options.current[key.toString()] !== value) {
-            var name = 'options.' + key.toString();
+    pause: false,                   // when enabled we don't auto-refresh the charts
 
-            if(typeof NETDATA.localStorage.default[name.toString()] === 'undefined')
-                console.log('localStorage: setOption() on unsaved option: "' + name.toString() + '", value: ' + value);
+    targets: [],                    // an array of all the state objects that are
+                                    // currently active (independently of their
+                                    // viewport visibility)
 
-            //console.log(NETDATA.localStorage);
-            //console.log('setOption: setting "' + key.toString() + '" to "' + value + '" of type ' + typeof(value) + ' original type ' + typeof(NETDATA.options.current[key.toString()]));
-            //console.log(NETDATA.options);
-            NETDATA.options.current[key.toString()] = NETDATA.localStorageSet(name.toString(), value, null);
+    updated_dom: true,              // when true, the DOM has been updated with
+                                    // new elements we have to check.
 
-            if(typeof NETDATA.options.current.setOptionCallback === 'function')
-                NETDATA.options.current.setOptionCallback();
-        }
+    auto_refresher_fast_weight: 0,  // this is the current time in ms, spent
+                                    // rendering charts continuously.
+                                    // used with .current.fast_render_timeframe
 
-        return true;
-    };
+    page_is_visible: true,          // when true, this page is visible
 
-    NETDATA.getOption = function(key) {
-        return NETDATA.options.current[key.toString()];
-    };
+    auto_refresher_stop_until: 0,   // timestamp in ms - used internally, to stop the
+                                    // auto-refresher for some time (when a chart is
+                                    // performing pan or zoom, we need to stop refreshing
+                                    // all other charts, to have the maximum speed for
+                                    // rendering the chart that is panned or zoomed).
+                                    // Used with .current.global_pan_sync_time
 
-    // read settings from local storage
-    NETDATA.localStorageGetRecursive(NETDATA.options.current, 'options', null);
+    on_scroll_refresher_stop_until: 0, // timestamp in ms - used to stop evaluating
+    // charts for some time, after a page scroll
 
-    // always start with this option enabled.
-    NETDATA.setOption('stop_updates_when_focus_is_lost', true);
+    last_page_resize: Date.now(),   // the timestamp of the last resize request
 
-    NETDATA.resetOptions = function() {
-        var keys = Object.keys(NETDATA.localStorage.default);
-        var len = keys.length;
-        while(len--) {
-            var i = keys[len];
-            var a = i.split('.');
+    last_page_scroll: 0,            // the timestamp the last time the page was scrolled
 
-            if(a[0] === 'options') {
-                if(a[1] === 'setOptionCallback') continue;
-                if(typeof NETDATA.localStorage.default[i] === 'undefined') continue;
-                if(NETDATA.options.current[i] === NETDATA.localStorage.default[i]) continue;
+    browser_timezone: 'unknown',    // timezone detected by javascript
+    server_timezone: 'unknown',     // timezone reported by the server
 
-                NETDATA.setOption(a[1], NETDATA.localStorage.default[i]);
-            }
-            else if(a[0] === 'chart_heights') {
-                if(typeof NETDATA.localStorage.callback[i] === 'function' && typeof NETDATA.localStorage.default[i] !== 'undefined') {
-                    NETDATA.localStorage.callback[i](NETDATA.localStorage.default[i]);
-                }
-            }
-        }
+    force_data_points: 0,           // force the number of points to be returned for charts
+    fake_chart_rendering: false,    // when set to true, the dashboard will download data but will not render the charts
 
-        NETDATA.dateTime.init(NETDATA.options.current.timezone);
-    };
+    passive_events: null,           // true if the browser supports passive events
 
-    // ----------------------------------------------------------------------------------------------------------------
+    // the current profile
+    // we may have many...
+    current: {
+        units: 'auto',              // can be 'auto' or 'original'
+        temperature: 'celsius',     // can be 'celsius' or 'fahrenheit'
+        seconds_as_time: true,      // show seconds as DDd:HH:MM:SS ?
+        timezone: 'default',        // the timezone to use, or 'default'
+        user_set_server_timezone: 'default', // as set by the user on the dashboard
 
-    if(NETDATA.options.debug.main_loop === true)
-        console.log('welcome to NETDATA');
+        legend_toolbox: true,       // show the legend toolbox on charts
+        resize_charts: true,        // show the resize handler on charts
 
-    NETDATA.onresizeCallback = null;
-    NETDATA.onresize = function() {
-        NETDATA.options.last_page_resize = Date.now();
-        NETDATA.onscroll();
+        pixels_per_point: isSlowDevice() ? 5 : 1, // the minimum pixels per point for all charts
+        // increase this to speed javascript up
+        // each chart library has its own limit too
+        // the max of this and the chart library is used
+        // the final is calculated every time, so a change
+        // here will have immediate effect on the next chart
+        // update
 
-        if(typeof NETDATA.onresizeCallback === 'function')
-            NETDATA.onresizeCallback();
-    };
+        idle_between_charts: 100,   // ms - how much time to wait between chart updates
 
-    NETDATA.abort_all_refreshes = function() {
-        var targets = NETDATA.options.targets;
-        var len = targets.length;
+        fast_render_timeframe: 200, // ms - render continuously until this time of continuous
+                                    // rendering has been reached
+                                    // this setting is used to make it render e.g. 10
+                                    // charts at once, sleep idle_between_charts time
+                                    // and continue for another 10 charts.
 
-        while (len--) {
-            if (targets[len].fetching_data === true) {
-                if (typeof targets[len].xhr !== 'undefined') {
-                    targets[len].xhr.abort();
-                    targets[len].running = false;
-                    targets[len].fetching_data = false;
-                }
-            }
-        }
-    };
+        idle_between_loops: 500,    // ms - if all charts have been updated, wait this
+                                    // time before starting again.
 
-    NETDATA.onscroll_start_delay = function() {
-        NETDATA.options.last_page_scroll = Date.now();
+        idle_parallel_loops: 100,   // ms - the time between parallel refresher updates
 
-        NETDATA.options.on_scroll_refresher_stop_until =
-            NETDATA.options.last_page_scroll
-            + ((NETDATA.options.current.async_on_scroll === true) ? 1000 : 0);
-    };
+        idle_lost_focus: 500,       // ms - when the window does not have focus, check
+                                    // if focus has been regained, every this time
 
-    NETDATA.onscroll_end_delay = function() {
-        NETDATA.options.on_scroll_refresher_stop_until =
-            Date.now()
-            + ((NETDATA.options.current.async_on_scroll === true) ? NETDATA.options.current.onscroll_worker_duration_threshold : 0);
-    };
+        global_pan_sync_time: 300,  // ms - when you pan or zoom a chart, the background
+                                    // auto-refreshing of charts is paused for this amount
+                                    // of time
 
-    NETDATA.onscroll_updater_timeout_id = undefined;
-    NETDATA.onscroll_updater = function() {
-        NETDATA.globalSelectionSync.stop();
+        sync_selection_delay: 400,  // ms - when you pan or zoom a chart, wait this amount
+                                    // of time before setting up synchronized selections
+                                    // on hover.
 
-        if(NETDATA.options.abort_ajax_on_scroll === true)
-            NETDATA.abort_all_refreshes();
+        sync_selection: true,       // enable or disable selection sync
 
-        // when the user scrolls he sees that we have
-        // hidden all the not-visible charts
-        // using this little function we try to switch
-        // the charts back to visible quickly
+        pan_and_zoom_delay: 50,     // when panning or zooming, how ofter to update the chart
 
-        if(NETDATA.intersectionObserver.enabled() === false) {
-            if (NETDATA.options.current.parallel_refresher === false) {
-                var targets = NETDATA.options.targets;
-                var len = targets.length;
+        sync_pan_and_zoom: true,    // enable or disable pan and zoom sync
 
-                while (len--)
-                    if (targets[len].running === false)
-                        targets[len].isVisible();
-            }
-        }
+        pan_and_zoom_data_padding: true, // fetch more data for the master chart when panning or zooming
 
-        NETDATA.onscroll_end_delay();
-    };
+        update_only_visible: true,  // enable or disable visibility management / used for printing
 
-    NETDATA.scrollUp = false;
-    NETDATA.scrollY = window.scrollY;
-    NETDATA.onscroll = function() {
-        //console.log('onscroll() begin');
+        parallel_refresher: !isSlowDevice(), // enable parallel refresh of charts
 
-        NETDATA.onscroll_start_delay();
-        NETDATA.chartRefresherReschedule();
+        concurrent_refreshes: true, // when parallel_refresher is enabled, sync also the charts
 
-        NETDATA.scrollUp = (window.scrollY > NETDATA.scrollY);
-        NETDATA.scrollY = window.scrollY;
+        destroy_on_hide: isSlowDevice(), // destroy charts when they are not visible
 
-        if(NETDATA.onscroll_updater_timeout_id)
-            NETDATA.timeout.clear(NETDATA.onscroll_updater_timeout_id);
+        show_help: netdataShowHelp, // when enabled the charts will show some help
+        show_help_delay_show_ms: 500,
+        show_help_delay_hide_ms: 0,
 
-        NETDATA.onscroll_updater_timeout_id = NETDATA.timeout.set(NETDATA.onscroll_updater, 0);
-        //console.log('onscroll() end');
-    };
+        eliminate_zero_dimensions: true, // do not show dimensions with just zeros
 
-    NETDATA.supportsPassiveEvents = function() {
-        if(NETDATA.options.passive_events === null) {
-            var supportsPassive = false;
-            try {
-                var opts = Object.defineProperty({}, 'passive', {
-                    get: function () {
-                        supportsPassive = true;
-                    }
-                });
-                window.addEventListener("test", null, opts);
-            } catch (e) {
-                console.log('browser does not support passive events');
-            }
+        stop_updates_when_focus_is_lost: true, // boolean - shall we stop auto-refreshes when document does not have user focus
+        stop_updates_while_resizing: 1000,  // ms - time to stop auto-refreshes while resizing the charts
 
-            NETDATA.options.passive_events = supportsPassive;
-        }
+        double_click_speed: 500,    // ms - time between clicks / taps to detect double click/tap
 
-        // console.log('passive ' + NETDATA.options.passive_events);
-        return NETDATA.options.passive_events;
-    };
+        smooth_plot: !isSlowDevice(), // enable smooth plot, where possible
 
-    window.addEventListener('resize', NETDATA.onresize, NETDATA.supportsPassiveEvents() ? { passive: true } : false);
-    window.addEventListener('scroll', NETDATA.onscroll, NETDATA.supportsPassiveEvents() ? { passive: true } : false);
-    // window.onresize = NETDATA.onresize;
-    // window.onscroll = NETDATA.onscroll;
+        color_fill_opacity_line: 1.0,
+        color_fill_opacity_area: 0.2,
+        color_fill_opacity_stacked: 0.8,
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Error Handling
-
-    NETDATA.errorCodes = {
-        100: { message: "Cannot load chart library", alert: true },
-        101: { message: "Cannot load jQuery", alert: true },
-        402: { message: "Chart library not found", alert: false },
-        403: { message: "Chart library not enabled/is failed", alert: false },
-        404: { message: "Chart not found", alert: false },
-        405: { message: "Cannot download charts index from server", alert: true },
-        406: { message: "Invalid charts index downloaded from server", alert: true },
-        407: { message: "Cannot HELLO netdata server", alert: false },
-        408: { message: "Netdata servers sent invalid response to HELLO", alert: false },
-        409: { message: "Cannot ACCESS netdata registry", alert: false },
-        410: { message: "Netdata registry ACCESS failed", alert: false },
-        411: { message: "Netdata registry server send invalid response to DELETE ", alert: false },
-        412: { message: "Netdata registry DELETE failed", alert: false },
-        413: { message: "Netdata registry server send invalid response to SWITCH ", alert: false },
-        414: { message: "Netdata registry SWITCH failed", alert: false },
-        415: { message: "Netdata alarms download failed", alert: false },
-        416: { message: "Netdata alarms log download failed", alert: false },
-        417: { message: "Netdata registry server send invalid response to SEARCH ", alert: false },
-        418: { message: "Netdata registry SEARCH failed", alert: false }
-    };
-    NETDATA.errorLast = {
-        code: 0,
-        message: "",
-        datetime: 0
-    };
+        pan_and_zoom_factor: 0.25,      // the increment when panning and zooming with the toolbox
+        pan_and_zoom_factor_multiplier_control: 2.0,
+        pan_and_zoom_factor_multiplier_shift: 3.0,
+        pan_and_zoom_factor_multiplier_alt: 4.0,
 
-    NETDATA.error = function(code, msg) {
-        NETDATA.errorLast.code = code;
-        NETDATA.errorLast.message = msg;
-        NETDATA.errorLast.datetime = Date.now();
+        abort_ajax_on_scroll: false,            // kill pending ajax page scroll
+        async_on_scroll: false,                 // sync/async onscroll handler
+        onscroll_worker_duration_threshold: 30, // time in ms, for async scroll handler
 
-        console.log("ERROR " + code + ": " + NETDATA.errorCodes[code].message + ": " + msg);
+        retries_on_data_failures: 3, // how many retries to make if we can't fetch chart data from the server
 
-        var ret = true;
-        if(typeof netdataErrorCallback === 'function') {
-           ret = netdataErrorCallback('system', code, msg);
+        setOptionCallback: function () {
         }
+    },
 
-        if(ret && NETDATA.errorCodes[code].alert)
-            alert("ERROR " + code + ": " + NETDATA.errorCodes[code].message + ": " + msg);
-    };
-
-    NETDATA.errorReset = function() {
-        NETDATA.errorLast.code = 0;
-        NETDATA.errorLast.message = "You are doing fine!";
-        NETDATA.errorLast.datetime = 0;
-    };
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // fast numbers formatting
-
-    NETDATA.fastNumberFormat = {
-        formatters_fixed: [],
-        formatters_zero_based: [],
-
-        // this is the fastest and the preferred
-        getIntlNumberFormat: function(min, max) {
-            var key = max;
-            if(min === max) {
-                if(typeof this.formatters_fixed[key] === 'undefined')
-                    this.formatters_fixed[key] = new Intl.NumberFormat(undefined, {
-                        // style: 'decimal',
-                        // minimumIntegerDigits: 1,
-                        // minimumSignificantDigits: 1,
-                        // maximumSignificantDigits: 1,
-                        useGrouping: true,
-                        minimumFractionDigits: min,
-                        maximumFractionDigits: max
-                    });
-
-                return this.formatters_fixed[key];
-            }
-            else if(min === 0) {
-                if(typeof this.formatters_zero_based[key] === 'undefined')
-                    this.formatters_zero_based[key] = new Intl.NumberFormat(undefined, {
-                        // style: 'decimal',
-                        // minimumIntegerDigits: 1,
-                        // minimumSignificantDigits: 1,
-                        // maximumSignificantDigits: 1,
-                        useGrouping: true,
-                        minimumFractionDigits: min,
-                        maximumFractionDigits: max
-                    });
-
-                return this.formatters_zero_based[key];
-            }
-            else {
-                // this is never used
-                // it is added just for completeness
-                return new Intl.NumberFormat(undefined, {
-                    // style: 'decimal',
-                    // minimumIntegerDigits: 1,
-                    // minimumSignificantDigits: 1,
-                    // maximumSignificantDigits: 1,
-                    useGrouping: true,
-                    minimumFractionDigits: min,
-                    maximumFractionDigits: max
-                });
-            }
-        },
+    debug: {
+        show_boxes: false,
+        main_loop: false,
+        focus: false,
+        visibility: false,
+        chart_data_url: false,
+        chart_errors: true, // remember to set it to false before merging
+        chart_timing: false,
+        chart_calls: false,
+        libraries: false,
+        dygraph: false,
+        globalSelectionSync: false,
+        globalPanAndZoom: false
+    }
+};
 
-        // this respects locale
-        getLocaleString: function(min, max) {
-            var key = max;
-            if(min === max) {
-                if(typeof this.formatters_fixed[key] === 'undefined')
-                    this.formatters_fixed[key] = {
-                        format: function (value) {
-                            return value.toLocaleString(undefined, {
-                                // style: 'decimal',
-                                // minimumIntegerDigits: 1,
-                                // minimumSignificantDigits: 1,
-                                // maximumSignificantDigits: 1,
-                                useGrouping: true,
-                                minimumFractionDigits: min,
-                                maximumFractionDigits: max
-                            });
-                        }
-                    };
+NETDATA.statistics = {
+    refreshes_total: 0,
+    refreshes_active: 0,
+    refreshes_active_max: 0
+};
 
-                return this.formatters_fixed[key];
-            }
-            else if(min === 0) {
-                if(typeof this.formatters_zero_based[key] === 'undefined')
-                    this.formatters_zero_based[key] = {
-                        format: function (value) {
-                            return value.toLocaleString(undefined, {
-                                // style: 'decimal',
-                                // minimumIntegerDigits: 1,
-                                // minimumSignificantDigits: 1,
-                                // maximumSignificantDigits: 1,
-                                useGrouping: true,
-                                minimumFractionDigits: min,
-                                maximumFractionDigits: max
-                            });
-                        }
-                    };
+// local storage options
 
-                return this.formatters_zero_based[key];
-            }
-            else {
-                return {
-                    format: function (value) {
-                        return value.toLocaleString(undefined, {
-                            // style: 'decimal',
-                            // minimumIntegerDigits: 1,
-                            // minimumSignificantDigits: 1,
-                            // maximumSignificantDigits: 1,
-                            useGrouping: true,
-                            minimumFractionDigits: min,
-                            maximumFractionDigits: max
-                        });
-                    }
-                };
-            }
-        },
+NETDATA.localStorage = {
+    default: {},
+    current: {},
+    callback: {} // only used for resetting back to defaults
+};
 
-        // the fallback
-        getFixed: function(min, max) {
-            var key = max;
-            if(min === max) {
-                if(typeof this.formatters_fixed[key] === 'undefined')
-                    this.formatters_fixed[key] = {
-                        format: function (value) {
-                            if(value === 0) return "0";
-                            return value.toFixed(max);
-                        }
-                    };
+NETDATA.localStorageTested = -1;
+NETDATA.localStorageTest = function () {
+    if (NETDATA.localStorageTested !== -1) {
+        return NETDATA.localStorageTested;
+    }
 
-                return this.formatters_fixed[key];
-            }
-            else if(min === 0) {
-                if(typeof this.formatters_zero_based[key] === 'undefined')
-                    this.formatters_zero_based[key] = {
-                        format: function (value) {
-                            if(value === 0) return "0";
-                            return value.toFixed(max);
-                        }
-                    };
+    if (typeof Storage !== "undefined" && typeof localStorage === 'object') {
+        let test = 'test';
+        try {
+            localStorage.setItem(test, test);
+            localStorage.removeItem(test);
+            NETDATA.localStorageTested = true;
+        } catch (e) {
+            NETDATA.localStorageTested = false;
+        }
+    } else {
+        NETDATA.localStorageTested = false;
+    }
 
-                return this.formatters_zero_based[key];
-            }
-            else {
-                return {
-                    format: function (value) {
-                        if(value === 0) return "0";
-                        return value.toFixed(max);
-                    }
-                };
-            }
-        },
+    return NETDATA.localStorageTested;
+};
 
-        testIntlNumberFormat: function() {
-            var value = 1.12345;
-            var e1 = "1.12", e2 = "1,12";
-            var s = "";
+NETDATA.localStorageGet = function (key, def, callback) {
+    let ret = def;
 
-            try {
-                var x = new Intl.NumberFormat(undefined, {
-                    useGrouping: true,
-                    minimumFractionDigits: 2,
-                    maximumFractionDigits: 2
-                });
+    if (typeof NETDATA.localStorage.default[key.toString()] === 'undefined') {
+        NETDATA.localStorage.default[key.toString()] = def;
+        NETDATA.localStorage.callback[key.toString()] = callback;
+    }
 
-                s = x.format(value);
-            }
-            catch(e) {
-                s = "";
+    if (NETDATA.localStorageTest()) {
+        try {
+            // console.log('localStorage: loading "' + key.toString() + '"');
+            ret = localStorage.getItem(key.toString());
+            // console.log('netdata loaded: ' + key.toString() + ' = ' + ret.toString());
+            if (ret === null || ret === 'undefined') {
+                // console.log('localStorage: cannot load it, saving "' + key.toString() + '" with value "' + JSON.stringify(def) + '"');
+                localStorage.setItem(key.toString(), JSON.stringify(def));
+                ret = def;
+            } else {
+                // console.log('localStorage: got "' + key.toString() + '" with value "' + ret + '"');
+                ret = JSON.parse(ret);
+                // console.log('localStorage: loaded "' + key.toString() + '" as value ' + ret + ' of type ' + typeof(ret));
             }
+        } catch (error) {
+            console.log('localStorage: failed to read "' + key.toString() + '", using default: "' + def.toString() + '"');
+            ret = def;
+        }
+    }
 
-            // console.log('NumberFormat: ', s);
-            return (s === e1 || s === e2);
-        },
+    if (typeof ret === 'undefined' || ret === 'undefined') {
+        console.log('localStorage: LOADED UNDEFINED "' + key.toString() + '" as value ' + ret + ' of type ' + typeof(ret));
+        ret = def;
+    }
 
-        testLocaleString: function() {
-            var value = 1.12345;
-            var e1 = "1.12", e2 = "1,12";
-            var s = "";
+    NETDATA.localStorage.current[key.toString()] = ret;
+    return ret;
+};
 
-            try {
-                s = value.toLocaleString(undefined, {
-                    useGrouping: true,
-                    minimumFractionDigits: 2,
-                    maximumFractionDigits: 2
-                });
-            }
-            catch(e) {
-                s = "";
-            }
+NETDATA.localStorageSet = function (key, value, callback) {
+    if (typeof value === 'undefined' || value === 'undefined') {
+        console.log('localStorage: ATTEMPT TO SET UNDEFINED "' + key.toString() + '" as value ' + value + ' of type ' + typeof(value));
+    }
 
-            // console.log('localeString: ', s);
-            return (s === e1 || s === e2);
-        },
+    if (typeof NETDATA.localStorage.default[key.toString()] === 'undefined') {
+        NETDATA.localStorage.default[key.toString()] = value;
+        NETDATA.localStorage.current[key.toString()] = value;
+        NETDATA.localStorage.callback[key.toString()] = callback;
+    }
 
-        // on first run we decide which formatter to use
-        get: function(min, max) {
-            if(this.testIntlNumberFormat()) {
-                // console.log('numberformat');
-                this.get = this.getIntlNumberFormat;
-            }
-            else if(this.testLocaleString()) {
-                // console.log('localestring');
-                this.get = this.getLocaleString;
-            }
-            else {
-                // console.log('fixed');
-                this.get = this.getFixed;
-            }
-            return this.get(min, max);
+    if (NETDATA.localStorageTest()) {
+        // console.log('localStorage: saving "' + key.toString() + '" with value "' + JSON.stringify(value) + '"');
+        try {
+            localStorage.setItem(key.toString(), JSON.stringify(value));
+        } catch (e) {
+            console.log('localStorage: failed to save "' + key.toString() + '" with value: "' + value.toString() + '"');
         }
-    };
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // element data attributes
-
-    NETDATA.dataAttribute = function(element, attribute, def) {
-        var key = 'data-' + attribute.toString();
-        if(element.hasAttribute(key) === true) {
-            var data = element.getAttribute(key);
-
-            if(data === 'true') return true;
-            if(data === 'false') return false;
-            if(data === 'null') return null;
+    }
 
-            // Only convert to a number if it doesn't change the string
-            if(data === +data + '') return +data;
+    NETDATA.localStorage.current[key.toString()] = value;
+    return value;
+};
 
-            if(/^(?:\{[\w\W]*\}|\[[\w\W]*\])$/.test(data))
-                return JSON.parse(data);
+NETDATA.localStorageGetRecursive = function (obj, prefix, callback) {
+    let keys = Object.keys(obj);
+    let len = keys.length;
+    while (len--) {
+        let i = keys[len];
 
-            return data;
+        if (typeof obj[i] === 'object') {
+            //console.log('object ' + prefix + '.' + i.toString());
+            NETDATA.localStorageGetRecursive(obj[i], prefix + '.' + i.toString(), callback);
+            continue;
         }
-        else return def;
-    };
 
-    NETDATA.dataAttributeBoolean = function(element, attribute, def) {
-        var value = NETDATA.dataAttribute(element, attribute, def);
+        obj[i] = NETDATA.localStorageGet(prefix + '.' + i.toString(), obj[i], callback);
+    }
+};
 
-        if(value === true || value === false)
-            return value;
+NETDATA.setOption = function (key, value) {
+    if (key.toString() === 'setOptionCallback') {
+        if (typeof NETDATA.options.current.setOptionCallback === 'function') {
+            NETDATA.options.current[key.toString()] = value;
+            NETDATA.options.current.setOptionCallback();
+        }
+    } else if (NETDATA.options.current[key.toString()] !== value) {
+        let name = 'options.' + key.toString();
 
-        if(typeof(value) === 'string') {
-            if(value === 'yes' || value === 'on')
-                return true;
+        if (typeof NETDATA.localStorage.default[name.toString()] === 'undefined') {
+            console.log('localStorage: setOption() on unsaved option: "' + name.toString() + '", value: ' + value);
+        }
 
-            if(value === '' || value === 'no' || value === 'off' || value === 'null')
-                return false;
+        //console.log(NETDATA.localStorage);
+        //console.log('setOption: setting "' + key.toString() + '" to "' + value + '" of type ' + typeof(value) + ' original type ' + typeof(NETDATA.options.current[key.toString()]));
+        //console.log(NETDATA.options);
+        NETDATA.options.current[key.toString()] = NETDATA.localStorageSet(name.toString(), value, null);
 
-            return def;
+        if (typeof NETDATA.options.current.setOptionCallback === 'function') {
+            NETDATA.options.current.setOptionCallback();
         }
+    }
 
-        if(typeof(value) === 'number')
-            return value !== 0;
-
-        return def;
-    };
+    return true;
+};
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // commonMin & commonMax
+NETDATA.getOption = function (key) {
+    return NETDATA.options.current[key.toString()];
+};
 
-    NETDATA.commonMin = {
-        keys: {},
-        latest: {},
+// read settings from local storage
+NETDATA.localStorageGetRecursive(NETDATA.options.current, 'options', null);
 
-        globalReset: function() {
-            this.keys = {};
-            this.latest = {};
-        },
+// always start with this option enabled.
+NETDATA.setOption('stop_updates_when_focus_is_lost', true);
 
-        get: function(state) {
-            if(typeof state.tmp.__commonMin === 'undefined') {
-                // get the commonMin setting
-                state.tmp.__commonMin = NETDATA.dataAttribute(state.element, 'common-min', null);
-            }
+NETDATA.resetOptions = function () {
+    let keys = Object.keys(NETDATA.localStorage.default);
+    let len = keys.length;
 
-            var min = state.data.min;
-            var name = state.tmp.__commonMin;
+    while (len--) {
+        let i = keys[len];
+        let a = i.split('.');
 
-            if(name === null) {
-                // we don't need commonMin
-                //state.log('no need for commonMin');
-                return min;
+        if (a[0] === 'options') {
+            if (a[1] === 'setOptionCallback') {
+                continue;
             }
-
-            var t = this.keys[name];
-            if(typeof t === 'undefined') {
-                // add our commonMin
-                this.keys[name] = {};
-                t = this.keys[name];
+            if (typeof NETDATA.localStorage.default[i] === 'undefined') {
+                continue;
             }
-
-            var uuid = state.uuid;
-            if(typeof t[uuid] !== 'undefined') {
-                if(t[uuid] === min) {
-                    //state.log('commonMin ' + state.tmp.__commonMin + ' not changed: ' + this.latest[name]);
-                    return this.latest[name];
-                }
-                else if(min < this.latest[name]) {
-                    //state.log('commonMin ' + state.tmp.__commonMin + ' increased: ' + min);
-                    t[uuid] = min;
-                    this.latest[name] = min;
-                    return min;
-                }
+            if (NETDATA.options.current[i] === NETDATA.localStorage.default[i]) {
+                continue;
             }
 
-            // add our min
-            t[uuid] = min;
-
-            // find the common min
-            var m = min;
-            for(var i in t)
-                if(t.hasOwnProperty(i) && t[i] < m) m = t[i];
-
-            //state.log('commonMin ' + state.tmp.__commonMin + ' updated: ' + m);
-            this.latest[name] = m;
-            return m;
+            NETDATA.setOption(a[1], NETDATA.localStorage.default[i]);
+        } else if (a[0] === 'chart_heights') {
+            if (typeof NETDATA.localStorage.callback[i] === 'function' && typeof NETDATA.localStorage.default[i] !== 'undefined') {
+                NETDATA.localStorage.callback[i](NETDATA.localStorage.default[i]);
+            }
         }
-    };
+    }
 
-    NETDATA.commonMax = {
-        keys: {},
-        latest: {},
+    NETDATA.dateTime.init(NETDATA.options.current.timezone);
+};
+// dygraph
 
-        globalReset: function() {
-            this.keys = {};
-            this.latest = {};
-        },
+NETDATA.dygraph = {
+    smooth: false
+};
 
-        get: function(state) {
-            if(typeof state.tmp.__commonMax === 'undefined') {
-                // get the commonMax setting
-                state.tmp.__commonMax = NETDATA.dataAttribute(state.element, 'common-max', null);
-            }
+NETDATA.dygraphToolboxPanAndZoom = function (state, after, before) {
+    if (after < state.netdata_first) {
+        after = state.netdata_first;
+    }
 
-            var max = state.data.max;
-            var name = state.tmp.__commonMax;
+    if (before > state.netdata_last) {
+        before = state.netdata_last;
+    }
 
-            if(name === null) {
-                // we don't need commonMax
-                //state.log('no need for commonMax');
-                return max;
-            }
+    state.setMode('zoom');
+    NETDATA.globalSelectionSync.stop();
+    NETDATA.globalSelectionSync.delay();
+    state.tmp.dygraph_user_action = true;
+    state.tmp.dygraph_force_zoom = true;
+    // state.log('toolboxPanAndZoom');
+    state.updateChartPanOrZoom(after, before);
+    NETDATA.globalPanAndZoom.setMaster(state, after, before);
+};
+
+NETDATA.dygraphSetSelection = function (state, t) {
+    if (typeof state.tmp.dygraph_instance !== 'undefined') {
+        let r = state.calculateRowForTime(t);
+        if (r !== -1) {
+            state.tmp.dygraph_instance.setSelection(r);
+            return true;
+        } else {
+            state.tmp.dygraph_instance.clearSelection();
+            state.legendShowUndefined();
+        }
+    }
 
-            var t = this.keys[name];
-            if(typeof t === 'undefined') {
-                // add our commonMax
-                this.keys[name] = {};
-                t = this.keys[name];
+    return false;
+};
+
+NETDATA.dygraphClearSelection = function (state) {
+    if (typeof state.tmp.dygraph_instance !== 'undefined') {
+        state.tmp.dygraph_instance.clearSelection();
+    }
+    return true;
+};
+
+NETDATA.dygraphSmoothInitialize = function (callback) {
+    $.ajax({
+        url: NETDATA.dygraph_smooth_js,
+        cache: true,
+        dataType: "script",
+        xhrFields: {withCredentials: true} // required for the cookie
+    })
+        .done(function () {
+            NETDATA.dygraph.smooth = true;
+            smoothPlotter.smoothing = 0.3;
+        })
+        .fail(function () {
+            NETDATA.dygraph.smooth = false;
+        })
+        .always(function () {
+            if (typeof callback === "function") {
+                return callback();
             }
+        });
+};
 
-            var uuid = state.uuid;
-            if(typeof t[uuid] !== 'undefined') {
-                if(t[uuid] === max) {
-                    //state.log('commonMax ' + state.tmp.__commonMax + ' not changed: ' + this.latest[name]);
-                    return this.latest[name];
-                }
-                else if(max > this.latest[name]) {
-                    //state.log('commonMax ' + state.tmp.__commonMax + ' increased: ' + max);
-                    t[uuid] = max;
-                    this.latest[name] = max;
-                    return max;
+NETDATA.dygraphInitialize = function (callback) {
+    if (typeof netdataNoDygraphs === 'undefined' || !netdataNoDygraphs) {
+        $.ajax({
+            url: NETDATA.dygraph_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function () {
+                NETDATA.registerChartLibrary('dygraph', NETDATA.dygraph_js);
+            })
+            .fail(function () {
+                NETDATA.chartLibraries.dygraph.enabled = false;
+                NETDATA.error(100, NETDATA.dygraph_js);
+            })
+            .always(function () {
+                if (NETDATA.chartLibraries.dygraph.enabled && NETDATA.options.current.smooth_plot) {
+                    NETDATA.dygraphSmoothInitialize(callback);
+                } else if (typeof callback === "function") {
+                    return callback();
                 }
-            }
+            });
+    } else {
+        NETDATA.chartLibraries.dygraph.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
+        }
+    }
+};
 
-            // add our max
-            t[uuid] = max;
+NETDATA.dygraphChartUpdate = function (state, data) {
+    let dygraph = state.tmp.dygraph_instance;
 
-            // find the common max
-            var m = max;
-            for(var i in t)
-                if(t.hasOwnProperty(i) && t[i] > m) m = t[i];
+    if (typeof dygraph === 'undefined') {
+        return NETDATA.dygraphChartCreate(state, data);
+    }
 
-            //state.log('commonMax ' + state.tmp.__commonMax + ' updated: ' + m);
-            this.latest[name] = m;
-            return m;
-        }
+    // when the chart is not visible, and hidden
+    // if there is a window resize, dygraph detects
+    // its element size as 0x0.
+    // this will make it re-appear properly
+
+    if (state.tm.last_unhidden > state.tmp.dygraph_last_rendered) {
+        dygraph.resize();
+    }
+
+    let options = {
+        file: data.result.data,
+        colors: state.chartColors(),
+        labels: data.result.labels,
+        //labelsDivWidth: state.chartWidth() - 70,
+        includeZero: state.tmp.dygraph_include_zero,
+        visibility: state.dimensions_visibility.selected2BooleanArray(state.data.dimension_names)
     };
 
-    NETDATA.commonColors = {
-        keys: {},
+    if (state.tmp.dygraph_chart_type === 'stacked') {
+        if (options.includeZero && state.dimensions_visibility.countSelected() < options.visibility.length) {
+            options.includeZero = 0;
+        }
+    }
 
-        globalReset: function() {
-            this.keys = {};
-        },
+    if (!NETDATA.chartLibraries.dygraph.isSparkline(state)) {
+        options.ylabel = state.units_current; // (state.units_desired === 'auto')?"":state.units_current;
+    }
 
-        get: function(state, label) {
-            var ret = this.refill(state);
+    if (state.tmp.dygraph_force_zoom) {
+        if (NETDATA.options.debug.dygraph || state.debug) {
+            state.log('dygraphChartUpdate() forced zoom update');
+        }
 
-            if(typeof ret.assigned[label] === 'undefined')
-                ret.assigned[label] = ret.available.shift();
+        options.dateWindow = (state.requested_padding !== null) ? [state.view_after, state.view_before] : null;
+        //options.isZoomedIgnoreProgrammaticZoom = true;
+        state.tmp.dygraph_force_zoom = false;
+    } else if (state.current.name !== 'auto') {
+        if (NETDATA.options.debug.dygraph || state.debug) {
+            state.log('dygraphChartUpdate() loose update');
+        }
+    } else {
+        if (NETDATA.options.debug.dygraph || state.debug) {
+            state.log('dygraphChartUpdate() strict update');
+        }
 
-            return ret.assigned[label];
-        },
+        options.dateWindow = (state.requested_padding !== null) ? [state.view_after, state.view_before] : null;
+        //options.isZoomedIgnoreProgrammaticZoom = true;
+    }
 
-        refill: function(state) {
-            var ret, len;
+    options.valueRange = state.tmp.dygraph_options.valueRange;
 
-            if(typeof state.tmp.__commonColors === 'undefined')
-                ret = this.prepare(state);
-            else {
-                ret = this.keys[state.tmp.__commonColors];
-                if(typeof ret === 'undefined')
-                    ret = this.prepare(state);
-            }
+    let oldMax = null, oldMin = null;
+    if (state.tmp.__commonMin !== null) {
+        state.data.min = state.tmp.dygraph_instance.axes_[0].extremeRange[0];
+        oldMin = options.valueRange[0] = NETDATA.commonMin.get(state);
+    }
+    if (state.tmp.__commonMax !== null) {
+        state.data.max = state.tmp.dygraph_instance.axes_[0].extremeRange[1];
+        oldMax = options.valueRange[1] = NETDATA.commonMax.get(state);
+    }
 
-            if(ret.available.length === 0) {
-                if(ret.copy_theme === true || ret.custom.length === 0) {
-                    // copy the theme colors
-                    len = NETDATA.themes.current.colors.length;
-                    while (len--)
-                        ret.available.unshift(NETDATA.themes.current.colors[len]);
-                }
+    if (state.tmp.dygraph_smooth_eligible) {
+        if ((NETDATA.options.current.smooth_plot && state.tmp.dygraph_options.plotter !== smoothPlotter)
+            || (NETDATA.options.current.smooth_plot === false && state.tmp.dygraph_options.plotter === smoothPlotter)) {
+            NETDATA.dygraphChartCreate(state, data);
+            return;
+        }
+    }
 
-                // copy the custom colors
-                len = ret.custom.length;
-                while (len--)
-                    ret.available.unshift(ret.custom[len]);
-            }
+    if (netdataSnapshotData !== null && NETDATA.globalPanAndZoom.isActive() && NETDATA.globalPanAndZoom.isMaster(state) === false) {
+        // pan and zoom on snapshots
+        options.dateWindow = [NETDATA.globalPanAndZoom.force_after_ms, NETDATA.globalPanAndZoom.force_before_ms];
+        //options.isZoomedIgnoreProgrammaticZoom = true;
+    }
 
-            state.colors_assigned = ret.assigned;
-            state.colors_available = ret.available;
-            state.colors_custom = ret.custom;
+    if (NETDATA.chartLibraries.dygraph.isLogScale(state)) {
+        if (Array.isArray(options.valueRange) && options.valueRange[0] <= 0) {
+            options.valueRange[0] = null;
+        }
+    }
 
-            return ret;
-        },
+    dygraph.updateOptions(options);
 
-        __read_custom_colors: function(state, ret) {
-            // add the user supplied colors
-            var c = NETDATA.dataAttribute(state.element, 'colors', undefined);
-            if (typeof c === 'string' && c.length > 0) {
-                c = c.split(' ');
-                var len = c.length;
+    let redraw = false;
+    if (oldMin !== null && oldMin > state.tmp.dygraph_instance.axes_[0].extremeRange[0]) {
+        state.data.min = state.tmp.dygraph_instance.axes_[0].extremeRange[0];
+        options.valueRange[0] = NETDATA.commonMin.get(state);
+        redraw = true;
+    }
+    if (oldMax !== null && oldMax < state.tmp.dygraph_instance.axes_[0].extremeRange[1]) {
+        state.data.max = state.tmp.dygraph_instance.axes_[0].extremeRange[1];
+        options.valueRange[1] = NETDATA.commonMax.get(state);
+        redraw = true;
+    }
 
-                if (len > 0 && c[len - 1] === 'ONLY') {
-                    len--;
-                    ret.copy_theme = false;
-                }
+    if (redraw) {
+        // state.log('forcing redraw to adapt to common- min/max');
+        dygraph.updateOptions(options);
+    }
 
-                while (len--)
-                    ret.custom.unshift(c[len]);
-            }
-        },
+    state.tmp.dygraph_last_rendered = Date.now();
+    return true;
+};
 
-        prepare: function(state) {
-            var has_custom_colors = false;
+NETDATA.dygraphChartCreate = function (state, data) {
+    if (NETDATA.options.debug.dygraph || state.debug) {
+        state.log('dygraphChartCreate()');
+    }
 
-            if(typeof state.tmp.__commonColors === 'undefined') {
-                var defname = state.chart.context;
+    state.tmp.dygraph_chart_type = NETDATA.dataAttribute(state.element, 'dygraph-type', state.chart.chart_type);
+    if (state.tmp.dygraph_chart_type === 'stacked' && data.dimensions === 1) {
+        state.tmp.dygraph_chart_type = 'area';
+    }
+    if (state.tmp.dygraph_chart_type === 'stacked' && NETDATA.chartLibraries.dygraph.isLogScale(state)) {
+        state.tmp.dygraph_chart_type = 'area';
+    }
 
-                // if this chart has data-colors=""
-                // we should use the chart uuid as the default key (private palette)
-                // (data-common-colors="NAME" will be used anyways)
-                var c = NETDATA.dataAttribute(state.element, 'colors', undefined);
-                if (typeof c === 'string' && c.length > 0) {
-                    defname = state.uuid;
-                    has_custom_colors = true;
+    let highlightCircleSize = NETDATA.chartLibraries.dygraph.isSparkline(state) ? 3 : 4;
+
+    let smooth = NETDATA.dygraph.smooth
+        ? (NETDATA.dataAttributeBoolean(state.element, 'dygraph-smooth', (state.tmp.dygraph_chart_type === 'line' && NETDATA.chartLibraries.dygraph.isSparkline(state) === false)))
+        : false;
+
+    state.tmp.dygraph_include_zero = NETDATA.dataAttribute(state.element, 'dygraph-includezero', (state.tmp.dygraph_chart_type === 'stacked'));
+    let drawAxis = NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawaxis', true);
+
+    state.tmp.dygraph_options = {
+        colors: NETDATA.dataAttribute(state.element, 'dygraph-colors', state.chartColors()),
+
+        // leave a few pixels empty on the right of the chart
+        rightGap: NETDATA.dataAttribute(state.element, 'dygraph-rightgap', 5),
+        showRangeSelector: NETDATA.dataAttributeBoolean(state.element, 'dygraph-showrangeselector', false),
+        showRoller: NETDATA.dataAttributeBoolean(state.element, 'dygraph-showroller', false),
+        title: NETDATA.dataAttribute(state.element, 'dygraph-title', state.title),
+        titleHeight: NETDATA.dataAttribute(state.element, 'dygraph-titleheight', 19),
+        legend: NETDATA.dataAttribute(state.element, 'dygraph-legend', 'always'), // we need this to get selection events
+        labels: data.result.labels,
+        labelsDiv: NETDATA.dataAttribute(state.element, 'dygraph-labelsdiv', state.element_legend_childs.hidden),
+        //labelsDivStyles:        NETDATA.dataAttribute(state.element, 'dygraph-labelsdivstyles', { 'fontSize':'1px' }),
+        //labelsDivWidth:         NETDATA.dataAttribute(state.element, 'dygraph-labelsdivwidth', state.chartWidth() - 70),
+        labelsSeparateLines: NETDATA.dataAttributeBoolean(state.element, 'dygraph-labelsseparatelines', true),
+        labelsShowZeroValues: NETDATA.chartLibraries.dygraph.isLogScale(state) ? false : NETDATA.dataAttributeBoolean(state.element, 'dygraph-labelsshowzerovalues', true),
+        labelsKMB: false,
+        labelsKMG2: false,
+        showLabelsOnHighlight: NETDATA.dataAttributeBoolean(state.element, 'dygraph-showlabelsonhighlight', true),
+        hideOverlayOnMouseOut: NETDATA.dataAttributeBoolean(state.element, 'dygraph-hideoverlayonmouseout', true),
+        includeZero: state.tmp.dygraph_include_zero,
+        xRangePad: NETDATA.dataAttribute(state.element, 'dygraph-xrangepad', 0),
+        yRangePad: NETDATA.dataAttribute(state.element, 'dygraph-yrangepad', 1),
+        valueRange: NETDATA.dataAttribute(state.element, 'dygraph-valuerange', [null, null]),
+        ylabel: state.units_current, // (state.units_desired === 'auto')?"":state.units_current,
+        yLabelWidth: NETDATA.dataAttribute(state.element, 'dygraph-ylabelwidth', 12),
+
+        // the function to plot the chart
+        plotter: null,
+
+        // The width of the lines connecting data points.
+        // This can be used to increase the contrast or some graphs.
+        strokeWidth: NETDATA.dataAttribute(state.element, 'dygraph-strokewidth', ((state.tmp.dygraph_chart_type === 'stacked') ? 0.1 : ((smooth === true) ? 1.5 : 0.7))),
+        strokePattern: NETDATA.dataAttribute(state.element, 'dygraph-strokepattern', undefined),
+
+        // The size of the dot to draw on each point in pixels (see drawPoints).
+        // A dot is always drawn when a point is "isolated",
+        // i.e. there is a missing point on either side of it.
+        // This also controls the size of those dots.
+        drawPoints: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawpoints', false),
+
+        // Draw points at the edges of gaps in the data.
+        // This improves visibility of small data segments or other data irregularities.
+        drawGapEdgePoints: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawgapedgepoints', true),
+        connectSeparatedPoints: NETDATA.chartLibraries.dygraph.isLogScale(state) ? false : NETDATA.dataAttributeBoolean(state.element, 'dygraph-connectseparatedpoints', false),
+        pointSize: NETDATA.dataAttribute(state.element, 'dygraph-pointsize', 1),
+
+        // enabling this makes the chart with little square lines
+        stepPlot: NETDATA.dataAttributeBoolean(state.element, 'dygraph-stepplot', false),
+
+        // Draw a border around graph lines to make crossing lines more easily
+        // distinguishable. Useful for graphs with many lines.
+        strokeBorderColor: NETDATA.dataAttribute(state.element, 'dygraph-strokebordercolor', NETDATA.themes.current.background),
+        strokeBorderWidth: NETDATA.dataAttribute(state.element, 'dygraph-strokeborderwidth', (state.tmp.dygraph_chart_type === 'stacked') ? 0.0 : 0.0),
+        fillGraph: NETDATA.dataAttribute(state.element, 'dygraph-fillgraph', (state.tmp.dygraph_chart_type === 'area' || state.tmp.dygraph_chart_type === 'stacked')),
+        fillAlpha: NETDATA.dataAttribute(state.element, 'dygraph-fillalpha',
+            ((state.tmp.dygraph_chart_type === 'stacked')
+                ? NETDATA.options.current.color_fill_opacity_stacked
+                : NETDATA.options.current.color_fill_opacity_area)
+        ),
+        stackedGraph: NETDATA.dataAttribute(state.element, 'dygraph-stackedgraph', (state.tmp.dygraph_chart_type === 'stacked')),
+        stackedGraphNaNFill: NETDATA.dataAttribute(state.element, 'dygraph-stackedgraphnanfill', 'none'),
+        drawAxis: drawAxis,
+        axisLabelFontSize: NETDATA.dataAttribute(state.element, 'dygraph-axislabelfontsize', 10),
+        axisLineColor: NETDATA.dataAttribute(state.element, 'dygraph-axislinecolor', NETDATA.themes.current.axis),
+        axisLineWidth: NETDATA.dataAttribute(state.element, 'dygraph-axislinewidth', 1.0),
+        drawGrid: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawgrid', true),
+        gridLinePattern: NETDATA.dataAttribute(state.element, 'dygraph-gridlinepattern', null),
+        gridLineWidth: NETDATA.dataAttribute(state.element, 'dygraph-gridlinewidth', 1.0),
+        gridLineColor: NETDATA.dataAttribute(state.element, 'dygraph-gridlinecolor', NETDATA.themes.current.grid),
+        maxNumberWidth: NETDATA.dataAttribute(state.element, 'dygraph-maxnumberwidth', 8),
+        sigFigs: NETDATA.dataAttribute(state.element, 'dygraph-sigfigs', null),
+        digitsAfterDecimal: NETDATA.dataAttribute(state.element, 'dygraph-digitsafterdecimal', 2),
+        valueFormatter: NETDATA.dataAttribute(state.element, 'dygraph-valueformatter', undefined),
+        highlightCircleSize: NETDATA.dataAttribute(state.element, 'dygraph-highlightcirclesize', highlightCircleSize),
+        highlightSeriesOpts: NETDATA.dataAttribute(state.element, 'dygraph-highlightseriesopts', null), // TOO SLOW: { strokeWidth: 1.5 },
+        highlightSeriesBackgroundAlpha: NETDATA.dataAttribute(state.element, 'dygraph-highlightseriesbackgroundalpha', null), // TOO SLOW: (state.tmp.dygraph_chart_type === 'stacked')?0.7:0.5,
+        pointClickCallback: NETDATA.dataAttribute(state.element, 'dygraph-pointclickcallback', undefined),
+        visibility: state.dimensions_visibility.selected2BooleanArray(state.data.dimension_names),
+        logscale: NETDATA.chartLibraries.dygraph.isLogScale(state) ? 'y' : undefined,
+
+        axes: {
+            x: {
+                pixelsPerLabel: NETDATA.dataAttribute(state.element, 'dygraph-xpixelsperlabel', 50),
+                ticker: Dygraph.dateTicker,
+                axisLabelWidth: NETDATA.dataAttribute(state.element, 'dygraph-xaxislabelwidth', 60),
+                drawAxis: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawxaxis', drawAxis),
+                axisLabelFormatter: function (d, gran) {
+                    void(gran);
+                    return NETDATA.dateTime.xAxisTimeString(d);
                 }
+            },
+            y: {
+                logscale: NETDATA.chartLibraries.dygraph.isLogScale(state) ? true : undefined,
+                pixelsPerLabel: NETDATA.dataAttribute(state.element, 'dygraph-ypixelsperlabel', 15),
+                axisLabelWidth: NETDATA.dataAttribute(state.element, 'dygraph-yaxislabelwidth', 50),
+                drawAxis: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawyaxis', drawAxis),
+                axisLabelFormatter: function (y) {
+
+                    // unfortunately, we have to call this every single time
+                    state.legendFormatValueDecimalsFromMinMax(
+                        this.axes_[0].extremeRange[0],
+                        this.axes_[0].extremeRange[1]
+                    );
 
-                // get the commonColors setting
-                state.tmp.__commonColors = NETDATA.dataAttribute(state.element, 'common-colors', defname);
-            }
+                    let old_units = this.user_attrs_.ylabel;
+                    let v = state.legendFormatValue(y);
+                    let new_units = state.units_current;
+
+                    if (state.units_desired === 'auto' && typeof old_units !== 'undefined' && new_units !== old_units && !NETDATA.chartLibraries.dygraph.isSparkline(state)) {
+                        // console.log(this);
+                        // state.log('units discrepancy: old = ' + old_units + ', new = ' + new_units);
+                        let len = this.plugins_.length;
+                        while (len--) {
+                            // console.log(this.plugins_[len]);
+                            if (typeof this.plugins_[len].plugin.ylabel_div_ !== 'undefined'
+                                && this.plugins_[len].plugin.ylabel_div_ !== null
+                                && typeof this.plugins_[len].plugin.ylabel_div_.children !== 'undefined'
+                                && this.plugins_[len].plugin.ylabel_div_.children !== null
+                                && typeof this.plugins_[len].plugin.ylabel_div_.children[0].children !== 'undefined'
+                                && this.plugins_[len].plugin.ylabel_div_.children[0].children !== null
+                            ) {
+                                this.plugins_[len].plugin.ylabel_div_.children[0].children[0].innerHTML = new_units;
+                                this.user_attrs_.ylabel = new_units;
+                                break;
+                            }
+                        }
 
-            var name = state.tmp.__commonColors;
-            var ret = this.keys[name];
+                        if (len < 0) {
+                            state.log('units discrepancy, but cannot find dygraphs div to change: old = ' + old_units + ', new = ' + new_units);
+                        }
+                    }
 
-            if(typeof ret === 'undefined') {
-                // add our commonMax
-                this.keys[name] = {
-                    assigned: {},       // name-value of dimensions and their colors
-                    available: [],      // an array of colors available to be used
-                    custom: [],         // the array of colors defined by the user
-                    charts: {},         // the charts linked to this
-                    copy_theme: true
-                };
-                ret = this.keys[name];
+                    return v;
+                }
+            }
+        },
+        legendFormatter: function (data) {
+            if (state.tmp.dygraph_mouse_down) {
+                return;
             }
 
-            if(typeof ret.charts[state.uuid] === 'undefined') {
-                ret.charts[state.uuid] = state;
+            let elements = state.element_legend_childs;
 
-                if(has_custom_colors === true)
-                    this.__read_custom_colors(state, ret);
+            // if the hidden div is not there
+            // we are not managing the legend
+            if (elements.hidden === null) {
+                return;
             }
 
-            return ret;
-        }
-    };
+            if (typeof data.x !== 'undefined') {
+                state.legendSetDate(data.x);
+                let i = data.series.length;
+                while (i--) {
+                    let series = data.series[i];
+                    if (series.isVisible) {
+                        state.legendSetLabelValue(series.label, series.y);
+                    } else {
+                        state.legendSetLabelValue(series.label, null);
+                    }
+                }
+            }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Chart Registry
+            return '';
+        },
+        drawCallback: function (dygraph, is_initial) {
 
-    // When multiple charts need the same chart, we avoid downloading it
-    // multiple times (and having it in browser memory multiple time)
-    // by using this registry.
+            // the user has panned the chart and this is called to re-draw the chart
+            // 1. refresh this chart by adding data to it
+            // 2. notify all the other charts about the update they need
 
-    // Every time we download a chart definition, we save it here with .add()
-    // Then we try to get it back with .get(). If that fails, we download it.
+            // to prevent an infinite loop (feedback), we use
+            //     state.tmp.dygraph_user_action
+            // - when true, this is initiated by a user
+            // - when false, this is feedback
 
-    NETDATA.fixHost = function(host) {
-        while(host.slice(-1) === '/')
-            host = host.substring(0, host.length - 1);
+            if (state.current.name !== 'auto' && state.tmp.dygraph_user_action) {
+                state.tmp.dygraph_user_action = false;
 
-        return host;
-    };
+                let x_range = dygraph.xAxisRange();
+                let after = Math.round(x_range[0]);
+                let before = Math.round(x_range[1]);
 
-    NETDATA.chartRegistry = {
-        charts: {},
+                if (NETDATA.options.debug.dygraph) {
+                    state.log('dygraphDrawCallback(dygraph, ' + is_initial + '): mode ' + state.current.name + ' ' + (after / 1000).toString() + ' - ' + (before / 1000).toString());
+                    //console.log(state);
+                }
 
-        globalReset: function() {
-            this.charts = {};
+                if (before <= state.netdata_last && after >= state.netdata_first) {
+                    // update only when we are within the data limits
+                    state.updateChartPanOrZoom(after, before);
+                }
+            }
         },
+        zoomCallback: function (minDate, maxDate, yRanges) {
 
-        add: function(host, id, data) {
-            if(typeof this.charts[host] === 'undefined')
-                this.charts[host] = {};
+            // the user has selected a range on the chart
+            // 1. refresh this chart by adding data to it
+            // 2. notify all the other charts about the update they need
 
-            //console.log('added ' + host + '/' + id);
-            this.charts[host][id] = data;
-        },
+            void(yRanges);
 
-        get: function(host, id) {
-            if(typeof this.charts[host] === 'undefined')
-                return null;
+            if (NETDATA.options.debug.dygraph) {
+                state.log('dygraphZoomCallback(): ' + state.current.name);
+            }
 
-            if(typeof this.charts[host][id] === 'undefined')
-                return null;
+            NETDATA.globalSelectionSync.stop();
+            NETDATA.globalSelectionSync.delay();
+            state.setMode('zoom');
 
-            //console.log('cached ' + host + '/' + id);
-            return this.charts[host][id];
+            // refresh it to the greatest possible zoom level
+            state.tmp.dygraph_user_action = true;
+            state.tmp.dygraph_force_zoom = true;
+            state.updateChartPanOrZoom(minDate, maxDate);
         },
+        highlightCallback: function (event, x, points, row, seriesName) {
+            void(seriesName);
 
-        downloadAll: function(host, callback) {
-            host = NETDATA.fixHost(host);
+            state.pauseChart();
 
-            var self = this;
+            // there is a bug in dygraph when the chart is zoomed enough
+            // the time it thinks is selected is wrong
+            // here we calculate the time t based on the row number selected
+            // which is ok
+            // let t = state.data_after + row * state.data_update_every;
+            // console.log('row = ' + row + ', x = ' + x + ', t = ' + t + ' ' + ((t === x)?'SAME':(Math.abs(x-t)<=state.data_update_every)?'SIMILAR':'DIFFERENT') + ', rows in db: ' + state.data_points + ' visible(x) = ' + state.timeIsVisible(x) + ' visible(t) = ' + state.timeIsVisible(t) + ' r(x) = ' + state.calculateRowForTime(x) + ' r(t) = ' + state.calculateRowForTime(t) + ' range: ' + state.data_after + ' - ' + state.data_before + ' real: ' + state.data.after + ' - ' + state.data.before + ' every: ' + state.data_update_every);
 
-            function got_data(h, data, callback) {
-                if(data !== null) {
-                    self.charts[h] = data.charts;
+            if (state.tmp.dygraph_mouse_down !== true) {
+                NETDATA.globalSelectionSync.sync(state, x);
+            }
 
-                    // update the server timezone in our options
-                    if(typeof data.timezone === 'string')
-                        NETDATA.options.server_timezone = data.timezone;
-                }
-                else NETDATA.error(406, h + '/api/v1/charts');
+            // fix legend zIndex using the internal structures of dygraph legend module
+            // this works, but it is a hack!
+            // state.tmp.dygraph_instance.plugins_[0].plugin.legend_div_.style.zIndex = 10000;
+        },
+        unhighlightCallback: function (event) {
+            void(event);
 
-                if(typeof callback === 'function')
-                    callback(data);
+            if (state.tmp.dygraph_mouse_down) {
+                return;
             }
 
-            if(netdataSnapshotData !== null) {
-                got_data(host, netdataSnapshotData.charts, callback);
-            }
-            else {
-                $.ajax({
-                    url: host + '/api/v1/charts',
-                    async: true,
-                    cache: false,
-                    xhrFields: {withCredentials: true} // required for the cookie
-                })
-                    .done(function (data) {
-                        data = NETDATA.xss.checkOptional('/api/v1/charts', data);
-                        got_data(host, data, callback);
-                    })
-                    .fail(function () {
-                        NETDATA.error(405, host + '/api/v1/charts');
-
-                        if (typeof callback === 'function')
-                            callback(null);
-                    });
+            if (NETDATA.options.debug.dygraph || state.debug) {
+                state.log('dygraphUnhighlightCallback()');
             }
-        }
-    };
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // Global Pan and Zoom on charts
-
-    // Using this structure are synchronize all the charts, so that
-    // when you pan or zoom one, all others are automatically refreshed
-    // to the same timespan.
 
-    NETDATA.globalPanAndZoom = {
-        seq: 0,                 // timestamp ms
-                                // every time a chart is panned or zoomed
-                                // we set the timestamp here
-                                // then we use it as a sequence number
-                                // to find if other charts are synchronized
-                                // to this time-range
-
-        master: null,           // the master chart (state), to which all others
-                                // are synchronized
-
-        force_before_ms: null,  // the timespan to sync all other charts
-        force_after_ms: null,
+            state.unpauseChart();
+            NETDATA.globalSelectionSync.stop();
+        },
+        underlayCallback: function (canvas, area, g) {
 
-        callback: null,
+            // the chart is about to be drawn
+            // this function renders global highlighted time-frame
 
-        globalReset: function() {
-            this.clearMaster();
-            this.seq = 0;
-            this.master = null;
-            this.force_after_ms = null;
-            this.force_before_ms = null;
-            this.callback = null;
-        },
+            if (NETDATA.globalChartUnderlay.isActive()) {
+                let after = NETDATA.globalChartUnderlay.after;
+                let before = NETDATA.globalChartUnderlay.before;
 
-        delay: function() {
-            if(NETDATA.options.debug.globalPanAndZoom === true)
-                console.log('globalPanAndZoom.delay()');
+                if (after < state.view_after) {
+                    after = state.view_after;
+                }
 
-            NETDATA.options.auto_refresher_stop_until = Date.now() + NETDATA.options.current.global_pan_sync_time;
-        },
+                if (before > state.view_before) {
+                    before = state.view_before;
+                }
 
-        // set a new master
-        setMaster: function(state, after, before) {
-            this.delay();
+                if (after < before) {
+                    let bottom_left = g.toDomCoords(after, -20);
+                    let top_right = g.toDomCoords(before, +20);
 
-            if(NETDATA.options.current.sync_pan_and_zoom === false)
-                return;
+                    let left = bottom_left[0];
+                    let right = top_right[0];
 
-            if(this.master === null) {
-                if(NETDATA.options.debug.globalPanAndZoom === true)
-                    console.log('globalPanAndZoom.setMaster(' + state.id + ', ' + after + ', ' + before + ') SET MASTER');
+                    canvas.fillStyle = NETDATA.themes.current.highlight;
+                    canvas.fillRect(left, area.y, right - left, area.h);
+                }
             }
-            else if(this.master !== state) {
-                if(NETDATA.options.debug.globalPanAndZoom === true)
-                    console.log('globalPanAndZoom.setMaster(' + state.id + ', ' + after + ', ' + before + ') CHANGED MASTER');
+        },
+        interactionModel: {
+            mousedown: function (event, dygraph, context) {
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.mousedown()');
+                }
 
-                this.master.resetChart(true, true);
-            }
+                state.tmp.dygraph_user_action = true;
 
-            var now = Date.now();
-            this.master = state;
-            this.seq = now;
-            this.force_after_ms = after;
-            this.force_before_ms = before;
+                if (NETDATA.options.debug.dygraph) {
+                    state.log('dygraphMouseDown()');
+                }
 
-            if(typeof this.callback === 'function')
-                this.callback(true, after, before);
-        },
+                // Right-click should not initiate anything.
+                if (event.button && event.button === 2) {
+                    return;
+                }
 
-        // clear the master
-        clearMaster: function() {
-            if(NETDATA.options.debug.globalPanAndZoom === true)
-                console.log('globalPanAndZoom.clearMaster()');
+                NETDATA.globalSelectionSync.stop();
+                NETDATA.globalSelectionSync.delay();
 
-            if(this.master !== null) {
-                var st = this.master;
-                this.master = null;
-                st.resetChart();
-            }
+                state.tmp.dygraph_mouse_down = true;
+                context.initializeMouseDown(event, dygraph, context);
 
-            this.master = null;
-            this.seq = 0;
-            this.force_after_ms = null;
-            this.force_before_ms = null;
-            NETDATA.options.auto_refresher_stop_until = 0;
+                //console.log(event);
+                if (event.button && event.button === 1) {
+                    if (event.shiftKey) {
+                        //console.log('middle mouse button dragging (PAN)');
 
-            if(typeof this.callback === 'function')
-                this.callback(false, 0, 0);
-        },
+                        state.setMode('pan');
+                        // NETDATA.globalSelectionSync.delay();
+                        state.tmp.dygraph_highlight_after = null;
+                        Dygraph.startPan(event, dygraph, context);
+                    } else if (event.altKey || event.ctrlKey || event.metaKey) {
+                        //console.log('middle mouse button highlight');
 
-        // is the given state the master of the global
-        // pan and zoom sync?
-        isMaster: function(state) {
-            return (this.master === state);
-        },
+                        if (!(event.offsetX && event.offsetY)) {
+                            event.offsetX = event.layerX - event.target.offsetLeft;
+                            event.offsetY = event.layerY - event.target.offsetTop;
+                        }
+                        state.tmp.dygraph_highlight_after = dygraph.toDataXCoord(event.offsetX);
+                        Dygraph.startZoom(event, dygraph, context);
+                    } else {
+                        //console.log('middle mouse button selection for zoom (ZOOM)');
 
-        // are we currently have a global pan and zoom sync?
-        isActive: function() {
-            return (this.master !== null && this.force_before_ms !== null && this.force_after_ms !== null && this.seq !== 0);
-        },
+                        state.setMode('zoom');
+                        // NETDATA.globalSelectionSync.delay();
+                        state.tmp.dygraph_highlight_after = null;
+                        Dygraph.startZoom(event, dygraph, context);
+                    }
+                } else {
+                    if (event.shiftKey) {
+                        //console.log('left mouse button selection for zoom (ZOOM)');
 
-        // check if a chart, other than the master
-        // needs to be refreshed, due to the global pan and zoom
-        shouldBeAutoRefreshed: function(state) {
-            if(this.master === null || this.seq === 0)
-                return false;
+                        state.setMode('zoom');
+                        // NETDATA.globalSelectionSync.delay();
+                        state.tmp.dygraph_highlight_after = null;
+                        Dygraph.startZoom(event, dygraph, context);
+                    } else if (event.altKey || event.ctrlKey || event.metaKey) {
+                        //console.log('left mouse button highlight');
 
-            //if(state.needsRecreation())
-            //  return true;
+                        if (!(event.offsetX && event.offsetY)) {
+                            event.offsetX = event.layerX - event.target.offsetLeft;
+                            event.offsetY = event.layerY - event.target.offsetTop;
+                        }
+                        state.tmp.dygraph_highlight_after = dygraph.toDataXCoord(event.offsetX);
+                        Dygraph.startZoom(event, dygraph, context);
+                    } else {
+                        //console.log('left mouse button dragging (PAN)');
 
-            return (state.tm.pan_and_zoom_seq !== this.seq);
-        }
-    };
+                        state.setMode('pan');
+                        // NETDATA.globalSelectionSync.delay();
+                        state.tmp.dygraph_highlight_after = null;
+                        Dygraph.startPan(event, dygraph, context);
+                    }
+                }
+            },
+            mousemove: function (event, dygraph, context) {
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.mousemove()');
+                }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // global chart underlay (time-frame highlighting)
-
-    NETDATA.globalChartUnderlay = {
-        callback: null,         // what to call when a highlighted range is setup
-        after: null,            // highlight after this time
-        before: null,           // highlight before this time
-        view_after: null,       // the charts after_ms viewport when the highlight was setup
-        view_before: null,      // the charts before_ms viewport, when the highlight was setup
-        state: null,            // the chart the highlight was setup
-
-        isActive: function() {
-            return (this.after !== null && this.before !== null);
-        },
+                if (state.tmp.dygraph_highlight_after !== null) {
+                    //console.log('highlight selection...');
 
-        hasViewport: function() {
-            return (this.state !== null && this.view_after !== null && this.view_before !== null);
-        },
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-        init: function(state, after, before, view_after, view_before) {
-            this.state = (typeof state !== 'undefined') ? state : null;
-            this.after = (typeof after !== 'undefined' && after !== null && after > 0) ? after : null;
-            this.before = (typeof before !== 'undefined' && before !== null && before > 0) ? before : null;
-            this.view_after = (typeof view_after !== 'undefined' && view_after !== null && view_after > 0) ? view_after : null;
-            this.view_before = (typeof view_before !== 'undefined' && view_before !== null && view_before > 0) ? view_before : null;
-        },
+                    state.tmp.dygraph_user_action = true;
+                    Dygraph.moveZoom(event, dygraph, context);
+                    event.preventDefault();
+                } else if (context.isPanning) {
+                    //console.log('panning...');
 
-        setup: function() {
-            if(this.isActive() === true) {
-                if (this.state === null)
-                    this.state = NETDATA.options.targets[0];
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-                if (typeof this.callback === 'function')
-                    this.callback(true, this.after, this.before);
-            }
-            else {
-                if (typeof this.callback === 'function')
-                    this.callback(false, 0, 0);
-            }
-        },
+                    state.tmp.dygraph_user_action = true;
+                    //NETDATA.globalSelectionSync.stop();
+                    //NETDATA.globalSelectionSync.delay();
+                    state.setMode('pan');
+                    context.is2DPan = false;
+                    Dygraph.movePan(event, dygraph, context);
+                } else if (context.isZooming) {
+                    //console.log('zooming...');
 
-        set: function(state, after, before, view_after, view_before) {
-            if(after > before) {
-                var t = after;
-                after = before;
-                before = t;
-            }
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-            this.init(state, after, before, view_after, view_before);
+                    state.tmp.dygraph_user_action = true;
+                    //NETDATA.globalSelectionSync.stop();
+                    //NETDATA.globalSelectionSync.delay();
+                    state.setMode('zoom');
+                    Dygraph.moveZoom(event, dygraph, context);
+                }
+            },
+            mouseup: function (event, dygraph, context) {
+                state.tmp.dygraph_mouse_down = false;
 
-            if (this.hasViewport() === true)
-                NETDATA.globalPanAndZoom.setMaster(this.state, this.view_after, this.view_before);
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.mouseup()');
+                }
 
-            this.setup();
-        },
+                if (state.tmp.dygraph_highlight_after !== null) {
+                    //console.log('done highlight selection');
 
-        clear: function() {
-            this.after = null;
-            this.before = null;
-            this.state = null;
-            this.view_after = null;
-            this.view_before = null;
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-            if(typeof this.callback === 'function')
-                this.callback(false, 0, 0);
-        },
+                    if (!(event.offsetX && event.offsetY)) {
+                        event.offsetX = event.layerX - event.target.offsetLeft;
+                        event.offsetY = event.layerY - event.target.offsetTop;
+                    }
 
-        focus: function() {
-            if(this.isActive() === true && this.hasViewport() === true) {
-                if(this.state === null)
-                    this.state = NETDATA.options.targets[0];
+                    NETDATA.globalChartUnderlay.set(state
+                        , state.tmp.dygraph_highlight_after
+                        , dygraph.toDataXCoord(event.offsetX)
+                        , state.view_after
+                        , state.view_before
+                    );
 
-                if(NETDATA.globalPanAndZoom.isMaster(this.state) === true)
-                    NETDATA.globalPanAndZoom.clearMaster();
+                    state.tmp.dygraph_highlight_after = null;
 
-                NETDATA.globalPanAndZoom.setMaster(this.state, this.view_after, this.view_before, true);
-            }
-        }
-    };
+                    context.isZooming = false;
+                    dygraph.clearZoomRect_();
+                    dygraph.drawGraph_(false);
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // dimensions selection
+                    // refresh all the charts immediately
+                    NETDATA.options.auto_refresher_stop_until = 0;
+                } else if (context.isPanning) {
+                    //console.log('done panning');
 
-    // TODO
-    // move color assignment to dimensions, here
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-    var dimensionStatus = function(parent, label, name_div, value_div, color) {
-        this.enabled = false;
-        this.parent = parent;
-        this.label = label;
-        this.name_div = null;
-        this.value_div = null;
-        this.color = NETDATA.themes.current.foreground;
-        this.selected = (parent.unselected_count === 0);
-
-        this.setOptions(name_div, value_div, color);
-    };
+                    state.tmp.dygraph_user_action = true;
+                    Dygraph.endPan(event, dygraph, context);
 
-    dimensionStatus.prototype.invalidate = function() {
-        this.name_div = null;
-        this.value_div = null;
-        this.enabled = false;
-    };
+                    // refresh all the charts immediately
+                    NETDATA.options.auto_refresher_stop_until = 0;
+                } else if (context.isZooming) {
+                    //console.log('done zomming');
 
-    dimensionStatus.prototype.setOptions = function(name_div, value_div, color) {
-        this.color = color;
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-        if(this.name_div !== name_div) {
-            this.name_div = name_div;
-            this.name_div.title = this.label;
-            this.name_div.style.setProperty('color', this.color, 'important');
-            if(this.selected === false)
-                this.name_div.className = 'netdata-legend-name not-selected';
-            else
-                this.name_div.className = 'netdata-legend-name selected';
-        }
+                    state.tmp.dygraph_user_action = true;
+                    Dygraph.endZoom(event, dygraph, context);
 
-        if(this.value_div !== value_div) {
-            this.value_div = value_div;
-            this.value_div.title = this.label;
-            this.value_div.style.setProperty('color', this.color, 'important');
-            if(this.selected === false)
-                this.value_div.className = 'netdata-legend-value not-selected';
-            else
-                this.value_div.className = 'netdata-legend-value selected';
-        }
+                    // refresh all the charts immediately
+                    NETDATA.options.auto_refresher_stop_until = 0;
+                }
+            },
+            click: function (event, dygraph, context) {
+                void(dygraph);
+                void(context);
 
-        this.enabled = true;
-        this.setHandler();
-    };
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.click()');
+                }
 
-    dimensionStatus.prototype.setHandler = function() {
-        if(this.enabled === false) return;
+                event.preventDefault();
+            },
+            dblclick: function (event, dygraph, context) {
+                void(event);
+                void(dygraph);
+                void(context);
 
-        var ds = this;
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.dblclick()');
+                }
+                NETDATA.resetAllCharts(state);
+            },
+            wheel: function (event, dygraph, context) {
+                void(context);
 
-        // this.name_div.onmousedown = this.value_div.onmousedown = function(e) {
-        this.name_div.onclick = this.value_div.onclick = function(e) {
-            e.preventDefault();
-            if(ds.isSelected()) {
-                // this is selected
-                if(e.shiftKey === true || e.ctrlKey === true) {
-                    // control or shift key is pressed -> unselect this (except is none will remain selected, in which case select all)
-                    ds.unselect();
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.wheel()');
+                }
 
-                    if(ds.parent.countSelected() === 0)
-                        ds.parent.selectAll();
+                // Take the offset of a mouse event on the dygraph canvas and
+                // convert it to a pair of percentages from the bottom left.
+                // (Not top left, bottom is where the lower value is.)
+                function offsetToPercentage(g, offsetX, offsetY) {
+                    // This is calculating the pixel offset of the leftmost date.
+                    let xOffset = g.toDomCoords(g.xAxisRange()[0], null)[0];
+                    let yar0 = g.yAxisRange(0);
+
+                    // This is calculating the pixel of the highest value. (Top pixel)
+                    let yOffset = g.toDomCoords(null, yar0[1])[1];
+
+                    // x y w and h are relative to the corner of the drawing area,
+                    // so that the upper corner of the drawing area is (0, 0).
+                    let x = offsetX - xOffset;
+                    let y = offsetY - yOffset;
+
+                    // This is computing the rightmost pixel, effectively defining the
+                    // width.
+                    let w = g.toDomCoords(g.xAxisRange()[1], null)[0] - xOffset;
+
+                    // This is computing the lowest pixel, effectively defining the height.
+                    let h = g.toDomCoords(null, yar0[0])[1] - yOffset;
+
+                    // Percentage from the left.
+                    let xPct = w === 0 ? 0 : (x / w);
+                    // Percentage from the top.
+                    let yPct = h === 0 ? 0 : (y / h);
+
+                    // The (1-) part below changes it from "% distance down from the top"
+                    // to "% distance up from the bottom".
+                    return [xPct, (1 - yPct)];
                 }
-                else {
-                    // no key is pressed -> select only this (except if it is the only selected already, in which case select all)
-                    if(ds.parent.countSelected() === 1) {
-                        ds.parent.selectAll();
+
+                // Adjusts [x, y] toward each other by zoomInPercentage%
+                // Split it so the left/bottom axis gets xBias/yBias of that change and
+                // tight/top gets (1-xBias)/(1-yBias) of that change.
+                //
+                // If a bias is missing it splits it down the middle.
+                function zoomRange(g, zoomInPercentage, xBias, yBias) {
+                    xBias = xBias || 0.5;
+                    yBias = yBias || 0.5;
+
+                    function adjustAxis(axis, zoomInPercentage, bias) {
+                        let delta = axis[1] - axis[0];
+                        let increment = delta * zoomInPercentage;
+                        let foo = [increment * bias, increment * (1 - bias)];
+
+                        return [axis[0] + foo[0], axis[1] - foo[1]];
                     }
-                    else {
-                        ds.parent.selectNone();
-                        ds.select();
+
+                    let yAxes = g.yAxisRanges();
+                    let newYAxes = [];
+                    for (let i = 0; i < yAxes.length; i++) {
+                        newYAxes[i] = adjustAxis(yAxes[i], zoomInPercentage, yBias);
                     }
+
+                    return adjustAxis(g.xAxisRange(), zoomInPercentage, xBias);
                 }
-            }
-            else {
-                // this is not selected
-                if(e.shiftKey === true || e.ctrlKey === true) {
-                    // control or shift key is pressed -> select this too
-                    ds.select();
-                }
-                else {
-                    // no key is pressed -> select only this
-                    ds.parent.selectNone();
-                    ds.select();
-                }
-            }
 
-            ds.parent.state.redrawChart();
-        }
-    };
+                if (event.altKey || event.shiftKey) {
+                    state.tmp.dygraph_user_action = true;
 
-    dimensionStatus.prototype.select = function() {
-        if(this.enabled === false) return;
+                    NETDATA.globalSelectionSync.stop();
+                    NETDATA.globalSelectionSync.delay();
 
-        this.name_div.className = 'netdata-legend-name selected';
-        this.value_div.className = 'netdata-legend-value selected';
-        this.selected = true;
-    };
+                    // http://dygraphs.com/gallery/interaction-api.js
+                    let normal_def;
+                    if (typeof event.wheelDelta === 'number' && !isNaN(event.wheelDelta))
+                    // chrome
+                    {
+                        normal_def = event.wheelDelta / 40;
+                    } else
+                    // firefox
+                    {
+                        normal_def = event.deltaY * -1.2;
+                    }
 
-    dimensionStatus.prototype.unselect = function() {
-        if(this.enabled === false) return;
+                    let normal = (event.detail) ? event.detail * -1 : normal_def;
+                    let percentage = normal / 50;
 
-        this.name_div.className = 'netdata-legend-name not-selected';
-        this.value_div.className = 'netdata-legend-value hidden';
-        this.selected = false;
-    };
+                    if (!(event.offsetX && event.offsetY)) {
+                        event.offsetX = event.layerX - event.target.offsetLeft;
+                        event.offsetY = event.layerY - event.target.offsetTop;
+                    }
 
-    dimensionStatus.prototype.isSelected = function() {
-        return(this.enabled === true && this.selected === true);
-    };
+                    let percentages = offsetToPercentage(dygraph, event.offsetX, event.offsetY);
+                    let xPct = percentages[0];
+                    let yPct = percentages[1];
 
-    // ----------------------------------------------------------------------------------------------------------------
+                    let new_x_range = zoomRange(dygraph, percentage, xPct, yPct);
+                    let after = new_x_range[0];
+                    let before = new_x_range[1];
 
-    var dimensionsVisibility = function(state) {
-        this.state = state;
-        this.len = 0;
-        this.dimensions = {};
-        this.selected_count = 0;
-        this.unselected_count = 0;
-    };
+                    let first = state.netdata_first + state.data_update_every;
+                    let last = state.netdata_last + state.data_update_every;
 
-    dimensionsVisibility.prototype.dimensionAdd = function(label, name_div, value_div, color) {
-        if(typeof this.dimensions[label] === 'undefined') {
-            this.len++;
-            this.dimensions[label] = new dimensionStatus(this, label, name_div, value_div, color);
-        }
-        else
-            this.dimensions[label].setOptions(name_div, value_div, color);
+                    if (before > last) {
+                        after -= (before - last);
+                        before = last;
+                    }
+                    if (after < first) {
+                        after = first;
+                    }
 
-        return this.dimensions[label];
-    };
-
-    dimensionsVisibility.prototype.dimensionGet = function(label) {
-        return this.dimensions[label];
-    };
-
-    dimensionsVisibility.prototype.invalidateAll = function() {
-        var keys = Object.keys(this.dimensions);
-        var len = keys.length;
-        while(len--)
-            this.dimensions[keys[len]].invalidate();
-    };
-
-    dimensionsVisibility.prototype.selectAll = function() {
-        var keys = Object.keys(this.dimensions);
-        var len = keys.length;
-        while(len--)
-            this.dimensions[keys[len]].select();
-    };
-
-    dimensionsVisibility.prototype.countSelected = function() {
-        var selected = 0;
-        var keys = Object.keys(this.dimensions);
-        var len = keys.length;
-        while(len--)
-            if(this.dimensions[keys[len]].isSelected()) selected++;
-
-        return selected;
-    };
-
-    dimensionsVisibility.prototype.selectNone = function() {
-        var keys = Object.keys(this.dimensions);
-        var len = keys.length;
-        while(len--)
-            this.dimensions[keys[len]].unselect();
-    };
-
-    dimensionsVisibility.prototype.selected2BooleanArray = function(array) {
-        var ret = [];
-        this.selected_count = 0;
-        this.unselected_count = 0;
-
-        var len = array.length;
-        while(len--) {
-            var ds = this.dimensions[array[len]];
-            if(typeof ds === 'undefined') {
-                // console.log(array[i] + ' is not found');
-                ret.unshift(false);
-            }
-            else if(ds.isSelected()) {
-                ret.unshift(true);
-                this.selected_count++;
-            }
-            else {
-                ret.unshift(false);
-                this.unselected_count++;
-            }
-        }
-
-        if(this.selected_count === 0 && this.unselected_count !== 0) {
-            this.selectAll();
-            return this.selected2BooleanArray(array);
-        }
-
-        return ret;
-    };
-
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // date/time conversion
+                    state.setMode('zoom');
+                    state.updateChartPanOrZoom(after, before, function () {
+                        dygraph.updateOptions({dateWindow: [after, before]});
+                    });
 
-    NETDATA.dateTime = {
-        using_timezone: false,
+                    event.preventDefault();
+                }
+            },
+            touchstart: function (event, dygraph, context) {
+                state.tmp.dygraph_mouse_down = true;
 
-        // these are the old netdata functions
-        // we fallback to these, if the new ones fail
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.touchstart()');
+                }
 
-        localeDateStringNative: function(d) {
-            return d.toLocaleDateString();
-        },
+                state.tmp.dygraph_user_action = true;
+                state.setMode('zoom');
+                state.pauseChart();
 
-        localeTimeStringNative: function(d) {
-            return d.toLocaleTimeString();
-        },
+                NETDATA.globalSelectionSync.stop();
+                NETDATA.globalSelectionSync.delay();
 
-        xAxisTimeStringNative: function(d) {
-            return NETDATA.zeropad(d.getHours())  + ":"
-                + NETDATA.zeropad(d.getMinutes()) + ":"
-                + NETDATA.zeropad(d.getSeconds());
-        },
+                Dygraph.defaultInteractionModel.touchstart(event, dygraph, context);
 
-        // initialize the new date/time conversion
-        // functions.
-        // if this fails, we fallback to the above
-        init: function(timezone) {
-            //console.log('init with timezone: ' + timezone);
+                // we overwrite the touch directions at the end, to overwrite
+                // the internal default of dygraph
+                context.touchDirections = {x: true, y: false};
 
-            // detect browser timezone
-            try {
-                NETDATA.options.browser_timezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
-            }
-            catch(e) {
-                console.log('failed to detect browser timezone: ' + e.toString());
-                NETDATA.options.browser_timezone = 'cannot-detect-it';
-            }
+                state.dygraph_last_touch_start = Date.now();
+                state.dygraph_last_touch_move = 0;
 
-            var ret = false;
+                if (typeof event.touches[0].pageX === 'number') {
+                    state.dygraph_last_touch_page_x = event.touches[0].pageX;
+                } else {
+                    state.dygraph_last_touch_page_x = 0;
+                }
+            },
+            touchmove: function (event, dygraph, context) {
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.touchmove()');
+                }
 
-            try {
-                var dateOptions ={
-                    localeMatcher: 'best fit',
-                    formatMatcher: 'best fit',
-                    weekday: 'short',
-                    year: 'numeric',
-                    month: 'short',
-                    day: '2-digit'
-                };
+                NETDATA.globalSelectionSync.stop();
+                NETDATA.globalSelectionSync.delay();
 
-                var timeOptions = {
-                    localeMatcher: 'best fit',
-                    hour12: false,
-                    formatMatcher: 'best fit',
-                    hour: '2-digit',
-                    minute: '2-digit',
-                    second: '2-digit'
-                };
+                state.tmp.dygraph_user_action = true;
+                Dygraph.defaultInteractionModel.touchmove(event, dygraph, context);
 
-                var xAxisOptions = {
-                    localeMatcher: 'best fit',
-                    hour12: false,
-                    formatMatcher: 'best fit',
-                    hour: '2-digit',
-                    minute: '2-digit',
-                    second: '2-digit'
-                };
+                state.dygraph_last_touch_move = Date.now();
+            },
+            touchend: function (event, dygraph, context) {
+                state.tmp.dygraph_mouse_down = false;
 
-                if(typeof timezone === 'string' && timezone !== '' && timezone !== 'default') {
-                    dateOptions.timeZone  = timezone;
-                    timeOptions.timeZone  = timezone;
-                    timeOptions.timeZoneName = 'short';
-                    xAxisOptions.timeZone = timezone;
-                    this.using_timezone = true;
-                }
-                else {
-                    timezone = 'default';
-                    this.using_timezone = false;
+                if (NETDATA.options.debug.dygraph || state.debug) {
+                    state.log('interactionModel.touchend()');
                 }
 
-                this.dateFormat  = new Intl.DateTimeFormat(navigator.language, dateOptions);
-                this.timeFormat  = new Intl.DateTimeFormat(navigator.language, timeOptions);
-                this.xAxisFormat = new Intl.DateTimeFormat(navigator.language, xAxisOptions);
+                NETDATA.globalSelectionSync.stop();
+                NETDATA.globalSelectionSync.delay();
 
-                this.localeDateString = function(d) {
-                    return this.dateFormat.format(d);
-                };
+                state.tmp.dygraph_user_action = true;
+                Dygraph.defaultInteractionModel.touchend(event, dygraph, context);
 
-                this.localeTimeString = function(d) {
-                    return this.timeFormat.format(d);
-                };
+                // if it didn't move, it is a selection
+                if (state.dygraph_last_touch_move === 0 && state.dygraph_last_touch_page_x !== 0) {
+                    NETDATA.globalSelectionSync.dont_sync_before = 0;
+                    NETDATA.globalSelectionSync.setMaster(state);
 
-                this.xAxisTimeString = function(d) {
-                    return this.xAxisFormat.format(d);
-                };
+                    // internal api of dygraph
+                    let pct = (state.dygraph_last_touch_page_x - (dygraph.plotter_.area.x + state.element.getBoundingClientRect().left)) / dygraph.plotter_.area.w;
+                    console.log('pct: ' + pct.toString());
 
-                //var d = new Date();
-                //var t = this.dateFormat.format(d) + ' ' + this.timeFormat.format(d) + ' ' + this.xAxisFormat.format(d);
+                    let t = Math.round(state.view_after + (state.view_before - state.view_after) * pct);
+                    if (NETDATA.dygraphSetSelection(state, t)) {
+                        NETDATA.globalSelectionSync.sync(state, t);
+                    }
+                }
 
-                ret = true;
-            }
-            catch(e) {
-                console.log('Cannot setup Date/Time formatting: ' + e.toString());
+                // if it was double tap within double click time, reset the charts
+                let now = Date.now();
+                if (typeof state.dygraph_last_touch_end !== 'undefined') {
+                    if (state.dygraph_last_touch_move === 0) {
+                        let dt = now - state.dygraph_last_touch_end;
+                        if (dt <= NETDATA.options.current.double_click_speed) {
+                            NETDATA.resetAllCharts(state);
+                        }
+                    }
+                }
 
-                timezone = 'default';
-                this.localeDateString = this.localeDateStringNative;
-                this.localeTimeString = this.localeTimeStringNative;
-                this.xAxisTimeString  = this.xAxisTimeStringNative;
-                this.using_timezone = false;
+                // remember the timestamp of the last touch end
+                state.dygraph_last_touch_end = now;
 
-                ret = false;
+                // refresh all the charts immediately
+                NETDATA.options.auto_refresher_stop_until = 0;
             }
-
-            // save it
-            //console.log('init setOption timezone: ' + timezone);
-            NETDATA.setOption('timezone', timezone);
-
-            return ret;
         }
     };
-    NETDATA.dateTime.init(NETDATA.options.current.timezone);
-
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // units conversion
-
-    NETDATA.unitsConversion = {
-        keys: {},       // keys for data-common-units
-        latest: {},     // latest selected units for data-common-units
 
-        globalReset: function() {
-            this.keys = {};
-            this.latest = {};
-        },
+    if (NETDATA.chartLibraries.dygraph.isLogScale(state)) {
+        if (Array.isArray(state.tmp.dygraph_options.valueRange) && state.tmp.dygraph_options.valueRange[0] <= 0) {
+            state.tmp.dygraph_options.valueRange[0] = null;
+        }
+    }
 
-        scalableUnits: {
-            'packets/s': {
-                'pps': 1,
-                'Kpps': 1000,
-                'Mpps': 1000000
-            },
-            'pps': {
-                'pps': 1,
-                'Kpps': 1000,
-                'Mpps': 1000000
-            },
-            'kilobits/s': {
-                'bits/s': 1 / 1000,
-                'kilobits/s': 1,
-                'megabits/s': 1000,
-                'gigabits/s': 1000000,
-                'terabits/s': 1000000000
-            },
-            'kilobytes/s': {
-                'bytes/s': 1 / 1024,
-                'kilobytes/s': 1,
-                'megabytes/s': 1024,
-                'gigabytes/s': 1024 * 1024,
-                'terabytes/s': 1024 * 1024 * 1024
-            },
-            'KB/s': {
-                'B/s': 1 / 1024,
-                'KB/s': 1,
-                'MB/s': 1024,
-                'GB/s': 1024 * 1024,
-                'TB/s': 1024 * 1024 * 1024
-            },
-            'KB': {
-                'B': 1 / 1024,
-                'KB': 1,
-                'MB': 1024,
-                'GB': 1024 * 1024,
-                'TB': 1024 * 1024 * 1024
-            },
-            'MB': {
-                'B':  1 / (1024 * 1024),
-                'KB': 1 / 1024,
-                'MB': 1,
-                'GB': 1024,
-                'TB': 1024 * 1024,
-                'PB': 1024 * 1024 * 1024
-            },
-            'GB': {
-                'B':  1 / (1024 * 1024 * 1024),
-                'KB': 1 / (1024 * 1024),
-                'MB': 1 / 1024,
-                'GB': 1,
-                'TB': 1024,
-                'PB': 1024 * 1024,
-                'EB': 1024 * 1024 * 1024
-            }
-            /*
-            'milliseconds': {
-                'seconds': 1000
-            },
-            'seconds': {
-                'milliseconds': 0.001,
-                'seconds': 1,
-                'minutes': 60,
-                'hours': 3600,
-                'days': 86400
-            }
-            */
-        },
+    if (NETDATA.chartLibraries.dygraph.isSparkline(state)) {
+        state.tmp.dygraph_options.drawGrid = false;
+        state.tmp.dygraph_options.drawAxis = false;
+        state.tmp.dygraph_options.title = undefined;
+        state.tmp.dygraph_options.ylabel = undefined;
+        state.tmp.dygraph_options.yLabelWidth = 0;
+        //state.tmp.dygraph_options.labelsDivWidth = 120;
+        //state.tmp.dygraph_options.labelsDivStyles.width = '120px';
+        state.tmp.dygraph_options.labelsSeparateLines = true;
+        state.tmp.dygraph_options.rightGap = 0;
+        state.tmp.dygraph_options.yRangePad = 1;
+        state.tmp.dygraph_options.axes.x.drawAxis = false;
+        state.tmp.dygraph_options.axes.y.drawAxis = false;
+    }
 
-        convertibleUnits: {
-            'Celsius': {
-                'Fahrenheit': {
-                    check: function(max) { void(max); return NETDATA.options.current.temperature === 'fahrenheit'; },
-                    convert: function(value) { return value * 9 / 5 + 32; }
-                }
-            },
-            'celsius': {
-                'fahrenheit': {
-                    check: function(max) { void(max); return NETDATA.options.current.temperature === 'fahrenheit'; },
-                    convert: function(value) { return value * 9 / 5 + 32; }
-                }
-            },
-            'seconds': {
-                'time': {
-                    check: function (max) { void(max); return NETDATA.options.current.seconds_as_time; },
-                    convert: function(seconds) { return NETDATA.unitsConversion.seconds2time(seconds); }
-                }
-            },
-            'milliseconds': {
-                'milliseconds': {
-                    check: function (max) { return NETDATA.options.current.seconds_as_time && max < 1000; },
-                    convert: function(milliseconds) {
-                        var tms = Math.round(milliseconds * 10);
-                        milliseconds = Math.floor(tms / 10);
+    if (smooth) {
+        state.tmp.dygraph_smooth_eligible = true;
 
-                        tms -= milliseconds * 10;
+        if (NETDATA.options.current.smooth_plot) {
+            state.tmp.dygraph_options.plotter = smoothPlotter;
+        }
+    }
+    else {
+        state.tmp.dygraph_smooth_eligible = false;
+    }
 
-                        return (milliseconds).toString() + '.' + tms.toString();
-                    }
-                },
-                'seconds': {
-                    check: function (max) { return NETDATA.options.current.seconds_as_time && max >= 1000 && max < 60000; },
-                    convert: function(milliseconds) {
-                        milliseconds = Math.round(milliseconds);
+    if (netdataSnapshotData !== null && NETDATA.globalPanAndZoom.isActive() && NETDATA.globalPanAndZoom.isMaster(state) === false) {
+        // pan and zoom on snapshots
+        state.tmp.dygraph_options.dateWindow = [NETDATA.globalPanAndZoom.force_after_ms, NETDATA.globalPanAndZoom.force_before_ms];
+        //state.tmp.dygraph_options.isZoomedIgnoreProgrammaticZoom = true;
+    }
 
-                        var seconds = Math.floor(milliseconds / 1000);
-                        milliseconds -= seconds * 1000;
+    state.tmp.dygraph_instance = new Dygraph(state.element_chart,
+        data.result.data, state.tmp.dygraph_options);
 
-                        milliseconds = Math.round(milliseconds / 10);
+    state.tmp.dygraph_force_zoom = false;
+    state.tmp.dygraph_user_action = false;
+    state.tmp.dygraph_last_rendered = Date.now();
+    state.tmp.dygraph_highlight_after = null;
 
-                        return seconds.toString() + '.'
-                            + NETDATA.zeropad(milliseconds);
-                    }
-                },
-                'M:SS.ms': {
-                    check: function (max) { return NETDATA.options.current.seconds_as_time && max >= 60000; },
-                    convert: function(milliseconds) {
-                        milliseconds = Math.round(milliseconds);
+    if (state.tmp.dygraph_options.valueRange[0] === null && state.tmp.dygraph_options.valueRange[1] === null) {
+        if (typeof state.tmp.dygraph_instance.axes_[0].extremeRange !== 'undefined') {
+            state.tmp.__commonMin = NETDATA.dataAttribute(state.element, 'common-min', null);
+            state.tmp.__commonMax = NETDATA.dataAttribute(state.element, 'common-max', null);
+        } else {
+            state.log('incompatible version of Dygraph detected');
+            state.tmp.__commonMin = null;
+            state.tmp.__commonMax = null;
+        }
+    } else {
+        // if the user gave a valueRange, respect it
+        state.tmp.__commonMin = null;
+        state.tmp.__commonMax = null;
+    }
 
-                        var minutes = Math.floor(milliseconds / 60000);
-                        milliseconds -= minutes * 60000;
+    return true;
+};
+// ----------------------------------------------------------------------------------------------------------------
+// sparkline
 
-                        var seconds = Math.floor(milliseconds / 1000);
-                        milliseconds -= seconds * 1000;
+NETDATA.sparklineInitialize = function (callback) {
+    if (typeof netdataNoSparklines === 'undefined' || !netdataNoSparklines) {
+        $.ajax({
+            url: NETDATA.sparkline_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function () {
+                NETDATA.registerChartLibrary('sparkline', NETDATA.sparkline_js);
+            })
+            .fail(function () {
+                NETDATA.chartLibraries.sparkline.enabled = false;
+                NETDATA.error(100, NETDATA.sparkline_js);
+            })
+            .always(function () {
+                if (typeof callback === "function") {
+                    return callback();
+                }
+            });
+    } else {
+        NETDATA.chartLibraries.sparkline.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
+        }
+    }
+};
+
+NETDATA.sparklineChartUpdate = function (state, data) {
+    state.sparkline_options.width = state.chartWidth();
+    state.sparkline_options.height = state.chartHeight();
+
+    $(state.element_chart).sparkline(data.result, state.sparkline_options);
+    return true;
+};
+
+NETDATA.sparklineChartCreate = function (state, data) {
+    let type = NETDATA.dataAttribute(state.element, 'sparkline-type', 'line');
+    let lineColor = NETDATA.dataAttribute(state.element, 'sparkline-linecolor', state.chartCustomColors()[0]);
+    let fillColor = NETDATA.dataAttribute(state.element, 'sparkline-fillcolor', ((state.chart.chart_type === 'line') ? NETDATA.themes.current.background : NETDATA.colorLuminance(lineColor, NETDATA.chartDefaults.fill_luminance)));
+    let chartRangeMin = NETDATA.dataAttribute(state.element, 'sparkline-chartrangemin', undefined);
+    let chartRangeMax = NETDATA.dataAttribute(state.element, 'sparkline-chartrangemax', undefined);
+    let composite = NETDATA.dataAttribute(state.element, 'sparkline-composite', undefined);
+    let enableTagOptions = NETDATA.dataAttribute(state.element, 'sparkline-enabletagoptions', undefined);
+    let tagOptionPrefix = NETDATA.dataAttribute(state.element, 'sparkline-tagoptionprefix', undefined);
+    let tagValuesAttribute = NETDATA.dataAttribute(state.element, 'sparkline-tagvaluesattribute', undefined);
+    let disableHiddenCheck = NETDATA.dataAttribute(state.element, 'sparkline-disablehiddencheck', undefined);
+    let defaultPixelsPerValue = NETDATA.dataAttribute(state.element, 'sparkline-defaultpixelspervalue', undefined);
+    let spotColor = NETDATA.dataAttribute(state.element, 'sparkline-spotcolor', undefined);
+    let minSpotColor = NETDATA.dataAttribute(state.element, 'sparkline-minspotcolor', undefined);
+    let maxSpotColor = NETDATA.dataAttribute(state.element, 'sparkline-maxspotcolor', undefined);
+    let spotRadius = NETDATA.dataAttribute(state.element, 'sparkline-spotradius', undefined);
+    let valueSpots = NETDATA.dataAttribute(state.element, 'sparkline-valuespots', undefined);
+    let highlightSpotColor = NETDATA.dataAttribute(state.element, 'sparkline-highlightspotcolor', undefined);
+    let highlightLineColor = NETDATA.dataAttribute(state.element, 'sparkline-highlightlinecolor', undefined);
+    let lineWidth = NETDATA.dataAttribute(state.element, 'sparkline-linewidth', undefined);
+    let normalRangeMin = NETDATA.dataAttribute(state.element, 'sparkline-normalrangemin', undefined);
+    let normalRangeMax = NETDATA.dataAttribute(state.element, 'sparkline-normalrangemax', undefined);
+    let drawNormalOnTop = NETDATA.dataAttribute(state.element, 'sparkline-drawnormalontop', undefined);
+    let xvalues = NETDATA.dataAttribute(state.element, 'sparkline-xvalues', undefined);
+    let chartRangeClip = NETDATA.dataAttribute(state.element, 'sparkline-chartrangeclip', undefined);
+    let chartRangeMinX = NETDATA.dataAttribute(state.element, 'sparkline-chartrangeminx', undefined);
+    let chartRangeMaxX = NETDATA.dataAttribute(state.element, 'sparkline-chartrangemaxx', undefined);
+    let disableInteraction = NETDATA.dataAttributeBoolean(state.element, 'sparkline-disableinteraction', false);
+    let disableTooltips = NETDATA.dataAttributeBoolean(state.element, 'sparkline-disabletooltips', false);
+    let disableHighlight = NETDATA.dataAttributeBoolean(state.element, 'sparkline-disablehighlight', false);
+    let highlightLighten = NETDATA.dataAttribute(state.element, 'sparkline-highlightlighten', 1.4);
+    let highlightColor = NETDATA.dataAttribute(state.element, 'sparkline-highlightcolor', undefined);
+    let tooltipContainer = NETDATA.dataAttribute(state.element, 'sparkline-tooltipcontainer', undefined);
+    let tooltipClassname = NETDATA.dataAttribute(state.element, 'sparkline-tooltipclassname', undefined);
+    let tooltipFormat = NETDATA.dataAttribute(state.element, 'sparkline-tooltipformat', undefined);
+    let tooltipPrefix = NETDATA.dataAttribute(state.element, 'sparkline-tooltipprefix', undefined);
+    let tooltipSuffix = NETDATA.dataAttribute(state.element, 'sparkline-tooltipsuffix', ' ' + state.units_current);
+    let tooltipSkipNull = NETDATA.dataAttributeBoolean(state.element, 'sparkline-tooltipskipnull', true);
+    let tooltipValueLookups = NETDATA.dataAttribute(state.element, 'sparkline-tooltipvaluelookups', undefined);
+    let tooltipFormatFieldlist = NETDATA.dataAttribute(state.element, 'sparkline-tooltipformatfieldlist', undefined);
+    let tooltipFormatFieldlistKey = NETDATA.dataAttribute(state.element, 'sparkline-tooltipformatfieldlistkey', undefined);
+    let numberFormatter = NETDATA.dataAttribute(state.element, 'sparkline-numberformatter', function (n) {
+        return n.toFixed(2);
+    });
+    let numberDigitGroupSep = NETDATA.dataAttribute(state.element, 'sparkline-numberdigitgroupsep', undefined);
+    let numberDecimalMark = NETDATA.dataAttribute(state.element, 'sparkline-numberdecimalmark', undefined);
+    let numberDigitGroupCount = NETDATA.dataAttribute(state.element, 'sparkline-numberdigitgroupcount', undefined);
+    let animatedZooms = NETDATA.dataAttributeBoolean(state.element, 'sparkline-animatedzooms', false);
 
-                        milliseconds = Math.round(milliseconds / 10);
+    if (spotColor === 'disable') {
+        spotColor = '';
+    }
+    if (minSpotColor === 'disable') {
+        minSpotColor = '';
+    }
+    if (maxSpotColor === 'disable') {
+        maxSpotColor = '';
+    }
 
-                        return minutes.toString() + ':'
-                            + NETDATA.zeropad(seconds) + '.'
-                            + NETDATA.zeropad(milliseconds);
-                    }
+    // state.log('sparkline type ' + type + ', lineColor: ' + lineColor + ', fillColor: ' + fillColor);
+
+    state.sparkline_options = {
+        type: type,
+        lineColor: lineColor,
+        fillColor: fillColor,
+        chartRangeMin: chartRangeMin,
+        chartRangeMax: chartRangeMax,
+        composite: composite,
+        enableTagOptions: enableTagOptions,
+        tagOptionPrefix: tagOptionPrefix,
+        tagValuesAttribute: tagValuesAttribute,
+        disableHiddenCheck: disableHiddenCheck,
+        defaultPixelsPerValue: defaultPixelsPerValue,
+        spotColor: spotColor,
+        minSpotColor: minSpotColor,
+        maxSpotColor: maxSpotColor,
+        spotRadius: spotRadius,
+        valueSpots: valueSpots,
+        highlightSpotColor: highlightSpotColor,
+        highlightLineColor: highlightLineColor,
+        lineWidth: lineWidth,
+        normalRangeMin: normalRangeMin,
+        normalRangeMax: normalRangeMax,
+        drawNormalOnTop: drawNormalOnTop,
+        xvalues: xvalues,
+        chartRangeClip: chartRangeClip,
+        chartRangeMinX: chartRangeMinX,
+        chartRangeMaxX: chartRangeMaxX,
+        disableInteraction: disableInteraction,
+        disableTooltips: disableTooltips,
+        disableHighlight: disableHighlight,
+        highlightLighten: highlightLighten,
+        highlightColor: highlightColor,
+        tooltipContainer: tooltipContainer,
+        tooltipClassname: tooltipClassname,
+        tooltipChartTitle: state.title,
+        tooltipFormat: tooltipFormat,
+        tooltipPrefix: tooltipPrefix,
+        tooltipSuffix: tooltipSuffix,
+        tooltipSkipNull: tooltipSkipNull,
+        tooltipValueLookups: tooltipValueLookups,
+        tooltipFormatFieldlist: tooltipFormatFieldlist,
+        tooltipFormatFieldlistKey: tooltipFormatFieldlistKey,
+        numberFormatter: numberFormatter,
+        numberDigitGroupSep: numberDigitGroupSep,
+        numberDecimalMark: numberDecimalMark,
+        numberDigitGroupCount: numberDigitGroupCount,
+        animatedZooms: animatedZooms,
+        width: state.chartWidth(),
+        height: state.chartHeight()
+    };
+
+    $(state.element_chart).sparkline(data.result, state.sparkline_options);
+
+    return true;
+};
+// google charts
+
+NETDATA.googleInitialize = function (callback) {
+    if (typeof netdataNoGoogleCharts === 'undefined' || !netdataNoGoogleCharts) {
+        $.ajax({
+            url: NETDATA.google_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function () {
+                NETDATA.registerChartLibrary('google', NETDATA.google_js);
+                google.load('visualization', '1.1', {
+                    'packages': ['corechart', 'controls'],
+                    'callback': callback
+                });
+            })
+            .fail(function () {
+                NETDATA.chartLibraries.google.enabled = false;
+                NETDATA.error(100, NETDATA.google_js);
+                if (typeof callback === "function") {
+                    return callback();
                 }
+            });
+    } else {
+        NETDATA.chartLibraries.google.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
+        }
+    }
+};
+
+NETDATA.googleChartUpdate = function (state, data) {
+    let datatable = new google.visualization.DataTable(data.result);
+    state.google_instance.draw(datatable, state.google_options);
+    return true;
+};
+
+NETDATA.googleChartCreate = function (state, data) {
+    let datatable = new google.visualization.DataTable(data.result);
+
+    state.google_options = {
+        colors: state.chartColors(),
+
+        // do not set width, height - the chart resizes itself
+        //width: state.chartWidth(),
+        //height: state.chartHeight(),
+        lineWidth: 1,
+        title: state.title,
+        fontSize: 11,
+        hAxis: {
+            //  title: "Time of Day",
+            //  format:'HH:mm:ss',
+            viewWindowMode: 'maximized',
+            slantedText: false,
+            format: 'HH:mm:ss',
+            textStyle: {
+                fontSize: 9
+            },
+            gridlines: {
+                color: '#EEE'
             }
         },
-
-        seconds2time: function(seconds) {
-            seconds = Math.abs(seconds);
-
-            var days = Math.floor(seconds / 86400);
-            seconds -= days * 86400;
-
-            var hours = Math.floor(seconds / 3600);
-            seconds -= hours * 3600;
-
-            var minutes = Math.floor(seconds / 60);
-            seconds -= minutes * 60;
-
-            seconds = Math.round(seconds);
-
-            var ms_txt = '';
-            /*
-            var ms = seconds - Math.floor(seconds);
-            seconds -= ms;
-            ms = Math.round(ms * 1000);
-
-            if(ms > 1) {
-                if(ms < 10)
-                    ms_txt = '.00' + ms.toString();
-                else if(ms < 100)
-                    ms_txt = '.0' + ms.toString();
-                else
-                    ms_txt = '.' + ms.toString();
+        vAxis: {
+            title: state.units_current,
+            viewWindowMode: 'pretty',
+            minValue: -0.1,
+            maxValue: 0.1,
+            direction: 1,
+            textStyle: {
+                fontSize: 9
+            },
+            gridlines: {
+                color: '#EEE'
             }
-            */
-
-            return ((days > 0)?days.toString() + 'd:':'').toString()
-                + NETDATA.zeropad(hours) + ':'
-                + NETDATA.zeropad(minutes) + ':'
-                + NETDATA.zeropad(seconds)
-                + ms_txt;
         },
-
-        // get a function that converts the units
-        // + every time units are switched call the callback
-        get: function(uuid, min, max, units, desired_units, common_units_name, switch_units_callback) {
-            // validate the parameters
-            if(typeof units === 'undefined')
-                units = 'undefined';
-
-            // check if we support units conversion
-            if(typeof this.scalableUnits[units] === 'undefined' && typeof this.convertibleUnits[units] === 'undefined') {
-                // we can't convert these units
-                //console.log('DEBUG: ' + uuid.toString() + ' can\'t convert units: ' + units.toString());
-                return function(value) { return value; };
+        chartArea: {
+            width: '65%',
+            height: '80%'
+        },
+        focusTarget: 'category',
+        annotation: {
+            '1': {
+                style: 'line'
             }
-
-            // check if the caller wants the original units
-            if(typeof desired_units === 'undefined' || desired_units === null || desired_units === 'original' || desired_units === units) {
-                //console.log('DEBUG: ' + uuid.toString() + ' original units wanted');
-                switch_units_callback(units);
-                return function(value) { return value; };
+        },
+        pointsVisible: 0,
+        titlePosition: 'out',
+        titleTextStyle: {
+            fontSize: 11
+        },
+        tooltip: {
+            isHtml: false,
+            ignoreBounds: true,
+            textStyle: {
+                fontSize: 9
             }
+        },
+        curveType: 'function',
+        areaOpacity: 0.3,
+        isStacked: false
+    };
+
+    switch (state.chart.chart_type) {
+        case "area":
+            state.google_options.vAxis.viewWindowMode = 'maximized';
+            state.google_options.areaOpacity = NETDATA.options.current.color_fill_opacity_area;
+            state.google_instance = new google.visualization.AreaChart(state.element_chart);
+            break;
+
+        case "stacked":
+            state.google_options.isStacked = true;
+            state.google_options.areaOpacity = NETDATA.options.current.color_fill_opacity_stacked;
+            state.google_options.vAxis.viewWindowMode = 'maximized';
+            state.google_options.vAxis.minValue = null;
+            state.google_options.vAxis.maxValue = null;
+            state.google_instance = new google.visualization.AreaChart(state.element_chart);
+            break;
+
+        default:
+        case "line":
+            state.google_options.lineWidth = 2;
+            state.google_instance = new google.visualization.LineChart(state.element_chart);
+            break;
+    }
 
-            // now we know we can convert the units
-            // and the caller wants some kind of conversion
-
-            var tunits = null;
-            var tdivider = 0;
-            var x;
-
-            if(typeof this.scalableUnits[units] !== 'undefined') {
-                // units that can be scaled
-                // we decide a divider
-
-                // console.log('NETDATA.unitsConversion.get(' + units.toString() + ', ' + desired_units.toString() + ', function()) decide divider with min = ' + min.toString() + ', max = ' + max.toString());
-
-                if (desired_units === 'auto') {
-                    // the caller wants to auto-scale the units
-
-                    // find the absolute maximum value that is rendered on the chart
-                    // based on this we decide the scale
-                    min = Math.abs(min);
-                    max = Math.abs(max);
-                    if (min > max) max = min;
-
-                    // find the smallest scale that provides integers
-                    for (x in this.scalableUnits[units]) {
-                        if (this.scalableUnits[units].hasOwnProperty(x)) {
-                            var m = this.scalableUnits[units][x];
-                            if (m <= max && m > tdivider) {
-                                tunits = x;
-                                tdivider = m;
-                            }
-                        }
-                    }
-
-                    if(tunits === null || tdivider <= 0) {
-                        // we couldn't find one
-                        //console.log('DEBUG: ' + uuid.toString() + ' cannot find an auto-scaling candidate for units: ' + units.toString() + ' (max: ' + max.toString() + ')');
-                        switch_units_callback(units);
-                        return function(value) { return value; };
-                    }
-
-                    if(typeof common_units_name === 'string' && typeof uuid === 'string') {
-                        // the caller wants several charts to have the same units
-                        // data-common-units
-
-                        var common_units_key = common_units_name + '-' + units;
-
-                        // add our divider into the list of keys
-                        var t = this.keys[common_units_key];
-                        if(typeof t === 'undefined') {
-                            this.keys[common_units_key] = {};
-                            t = this.keys[common_units_key];
-                        }
-                        t[uuid] = {
-                            units: tunits,
-                            divider: tdivider
-                        };
-
-                        // find the max divider of all charts
-                        var common_units = t[uuid];
-                        for(x in t) {
-                            if (t.hasOwnProperty(x) && t[x].divider > common_units.divider)
-                                common_units = t[x];
-                        }
-
-                        // save our common_max to the latest keys
-                        var latest = this.latest[common_units_key];
-                        if(typeof latest === 'undefined') {
-                            this.latest[common_units_key] = {};
-                            latest = this.latest[common_units_key];
-                        }
-                        latest.units = common_units.units;
-                        latest.divider = common_units.divider;
-
-                        tunits = latest.units;
-                        tdivider = latest.divider;
-
-                        //console.log('DEBUG: ' + uuid.toString() + ' converted units: ' + units.toString() + ' to units: ' + tunits.toString() + ' with divider ' + tdivider.toString() + ', common-units=' + common_units_name.toString() + ((t[uuid].divider !== tdivider)?' USED COMMON, mine was ' + t[uuid].units:' set common').toString());
-
-                        // apply it to this chart
-                        switch_units_callback(tunits);
-                        return function(value) {
-                            if(tdivider !== latest.divider) {
-                                // another chart switched our common units
-                                // we should switch them too
-                                //console.log('DEBUG: ' + uuid + ' switching units due to a common-units change, from ' + tunits.toString() + ' to ' + latest.units.toString());
-                                tunits = latest.units;
-                                tdivider = latest.divider;
-                                switch_units_callback(tunits);
-                            }
-
-                            return value / tdivider;
-                        };
-                    }
-                    else {
-                        // the caller did not give data-common-units
-                        // this chart auto-scales independently of all others
-                        //console.log('DEBUG: ' + uuid.toString() + ' converted units: ' + units.toString() + ' to units: ' + tunits.toString() + ' with divider ' + tdivider.toString() + ', autonomously');
+    state.google_instance.draw(datatable, state.google_options);
+    return true;
+};
+// gauge.js
 
-                        switch_units_callback(tunits);
-                        return function (value) { return value / tdivider; };
-                    }
-                }
-                else {
-                    // the caller wants specific units
-
-                    if(typeof this.scalableUnits[units][desired_units] !== 'undefined') {
-                        // all good, set the new units
-                        tdivider = this.scalableUnits[units][desired_units];
-                        // console.log('DEBUG: ' + uuid.toString() + ' converted units: ' + units.toString() + ' to units: ' + desired_units.toString() + ' with divider ' + tdivider.toString() + ', by reference');
-                        switch_units_callback(desired_units);
-                        return function (value) { return value / tdivider; };
-                    }
-                    else {
-                        // oops! switch back to original units
-                        console.log('Units conversion from ' + units.toString() + ' to ' + desired_units.toString() + ' is not supported.');
-                        switch_units_callback(units);
-                        return function (value) { return value; };
-                    }
-                }
-           }
-           else if(typeof this.convertibleUnits[units] !== 'undefined') {
-                // units that can be converted
-                if(desired_units === 'auto') {
-                    for(x in this.convertibleUnits[units]) {
-                        if (this.convertibleUnits[units].hasOwnProperty(x)) {
-                            if (this.convertibleUnits[units][x].check(max)) {
-                                //console.log('DEBUG: ' + uuid.toString() + ' converting ' + units.toString() + ' to: ' + x.toString());
-                                switch_units_callback(x);
-                                return this.convertibleUnits[units][x].convert;
-                            }
-                        }
-                    }
-
-                    // none checked ok
-                    //console.log('DEBUG: ' + uuid.toString() + ' no conversion available for ' + units.toString() + ' to: ' + desired_units.toString());
-                    switch_units_callback(units);
-                    return function (value) { return value; };
-                }
-                else if(typeof this.convertibleUnits[units][desired_units] !== 'undefined') {
-                    switch_units_callback(desired_units);
-                    return this.convertibleUnits[units][desired_units].convert;
-                }
-                else {
-                    console.log('Units conversion from ' + units.toString() + ' to ' + desired_units.toString() + ' is not supported.');
-                    switch_units_callback(units);
-                    return function (value) { return value; };
+NETDATA.gaugeInitialize = function (callback) {
+    if (typeof netdataNoGauge === 'undefined' || !netdataNoGauge) {
+        $.ajax({
+            url: NETDATA.gauge_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function () {
+                NETDATA.registerChartLibrary('gauge', NETDATA.gauge_js);
+            })
+            .fail(function () {
+                NETDATA.chartLibraries.gauge.enabled = false;
+                NETDATA.error(100, NETDATA.gauge_js);
+            })
+            .always(function () {
+                if (typeof callback === "function") {
+                    return callback();
                 }
-           }
-           else {
-                // hm... did we forget to implement the new type?
-                console.log('Unmatched unit conversion method for units ' + units.toString());
-                switch_units_callback(units);
-                return function (value) { return value; };
-           }
+            })
+    }
+    else {
+        NETDATA.chartLibraries.gauge.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
         }
-    };
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // global selection sync
-
-    NETDATA.globalSelectionSync = {
-        state: null,
-        dont_sync_before: 0,
-        last_t: 0,
-        slaves: [],
-        timeout_id: undefined,
-
-        globalReset: function() {
-            this.stop();
-            this.state = null;
-            this.dont_sync_before =  0;
-            this.last_t = 0;
-            this.slaves = [];
-            this.timeout_id = undefined;
-        },
+    }
+};
 
-        active: function() {
-            return (this.state !== null);
-        },
+NETDATA.gaugeAnimation = function (state, status) {
+    let speed = 32;
 
-        // return true if global selection sync can be enabled now
-        enabled: function() {
-            // console.log('enabled()');
-            // can we globally apply selection sync?
-            if(NETDATA.options.current.sync_selection === false)
-                return false;
+    if (typeof status === 'boolean' && status === false) {
+        speed = 1000000000;
+    } else if (typeof status === 'number') {
+        speed = status;
+    }
 
-            return (this.dont_sync_before <= Date.now());
-        },
+    // console.log('gauge speed ' + speed);
+    state.tmp.gauge_instance.animationSpeed = speed;
+    state.tmp.___gaugeOld__.speed = speed;
+};
 
-        // set the global selection sync master
-        setMaster: function(state) {
-            if(this.enabled() === false) {
-                this.stop();
-                return;
-            }
-
-            if(this.state === state)
-                return;
+NETDATA.gaugeSet = function (state, value, min, max) {
+    if (typeof value !== 'number') {
+        value = 0;
+    }
+    if (typeof min !== 'number') {
+        min = 0;
+    }
+    if (typeof max !== 'number') {
+        max = 0;
+    }
+    if (value > max) {
+        max = value;
+    }
+    if (value < min) {
+        min = value;
+    }
+    if (min > max) {
+        let t = min;
+        min = max;
+        max = t;
+    }
+    else if (min === max) {
+        max = min + 1;
+    }
 
-            if(this.state !== null)
-                this.stop();
+    state.legendFormatValueDecimalsFromMinMax(min, max);
 
-            if(NETDATA.options.debug.globalSelectionSync === true)
-                console.log('globalSelectionSync.setMaster(' + state.id + ')');
+    // gauge.js has an issue if the needle
+    // is smaller than min or larger than max
+    // when we set the new values
+    // the needle will go crazy
 
-            state.selected = true;
-            this.state = state;
-            this.last_t = 0;
+    // to prevent it, we always feed it
+    // with a percentage, so that the needle
+    // is always between min and max
+    let pcent = (value - min) * 100 / (max - min);
 
-            // find all slaves
-            var targets = NETDATA.intersectionObserver.targets();
-            this.slaves = [];
-            var len = targets.length;
-            while(len--) {
-                var st = targets[len];
-                if (this.state !== st && st.globalSelectionSyncIsEligible() === true)
-                    this.slaves.push(st);
-            }
+    // bug fix for gauge.js 1.3.1
+    // if the value is the absolute min or max, the chart is broken
+    if (pcent < 0.001) {
+        pcent = 0.001;
+    }
+    if (pcent > 99.999) {
+        pcent = 99.999;
+    }
 
-            // this.delay(100);
-        },
+    state.tmp.gauge_instance.set(pcent);
+    // console.log('gauge set ' + pcent + ', value ' + value + ', min ' + min + ', max ' + max);
 
-        // stop global selection sync
-        stop: function() {
-            if(this.state !== null) {
-                if(NETDATA.options.debug.globalSelectionSync === true)
-                    console.log('globalSelectionSync.stop()');
+    state.tmp.___gaugeOld__.value = value;
+    state.tmp.___gaugeOld__.min = min;
+    state.tmp.___gaugeOld__.max = max;
+};
 
-                var len = this.slaves.length;
-                while (len--)
-                    this.slaves[len].clearSelection();
+NETDATA.gaugeSetLabels = function (state, value, min, max) {
+    if (state.tmp.___gaugeOld__.valueLabel !== value) {
+        state.tmp.___gaugeOld__.valueLabel = value;
+        state.tmp.gaugeChartLabel.innerText = state.legendFormatValue(value);
+    }
+    if (state.tmp.___gaugeOld__.minLabel !== min) {
+        state.tmp.___gaugeOld__.minLabel = min;
+        state.tmp.gaugeChartMin.innerText = state.legendFormatValue(min);
+    }
+    if (state.tmp.___gaugeOld__.maxLabel !== max) {
+        state.tmp.___gaugeOld__.maxLabel = max;
+        state.tmp.gaugeChartMax.innerText = state.legendFormatValue(max);
+    }
+};
 
-                this.state.clearSelection();
+NETDATA.gaugeClearSelection = function (state, force) {
+    if (typeof state.tmp.gaugeEvent !== 'undefined' && typeof state.tmp.gaugeEvent.timer !== 'undefined') {
+        NETDATA.timeout.clear(state.tmp.gaugeEvent.timer);
+        state.tmp.gaugeEvent.timer = undefined;
+    }
 
-                this.last_t = 0;
-                this.slaves = [];
-                this.state = null;
-            }
-        },
+    if (state.isAutoRefreshable() && state.data !== null && force !== true) {
+        NETDATA.gaugeChartUpdate(state, state.data);
+    } else {
+        NETDATA.gaugeAnimation(state, false);
+        NETDATA.gaugeSetLabels(state, null, null, null);
+        NETDATA.gaugeSet(state, null, null, null);
+    }
 
-        // delay global selection sync for some time
-        delay: function(ms) {
-            if(NETDATA.options.current.sync_selection === true) {
-                if(NETDATA.options.debug.globalSelectionSync === true)
-                    console.log('globalSelectionSync.delay()');
+    NETDATA.gaugeAnimation(state, true);
+    return true;
+};
 
-                if(typeof ms === 'number')
-                    this.dont_sync_before = Date.now() + ms;
-                else
-                    this.dont_sync_before = Date.now() + NETDATA.options.current.sync_selection_delay;
-            }
-        },
+NETDATA.gaugeSetSelection = function (state, t) {
+    if (state.timeIsVisible(t) !== true) {
+        return NETDATA.gaugeClearSelection(state, true);
+    }
 
-        __syncSlaves: function() {
-            if(NETDATA.globalSelectionSync.enabled() === true) {
-                if(NETDATA.options.debug.globalSelectionSync === true)
-                    console.log('globalSelectionSync.__syncSlaves()');
+    let slot = state.calculateRowForTime(t);
+    if (slot < 0 || slot >= state.data.result.length) {
+        return NETDATA.gaugeClearSelection(state, true);
+    }
 
-                var t = NETDATA.globalSelectionSync.last_t;
-                var len = NETDATA.globalSelectionSync.slaves.length;
-                while (len--)
-                    NETDATA.globalSelectionSync.slaves[len].setSelection(t);
+    if (typeof state.tmp.gaugeEvent === 'undefined') {
+        state.tmp.gaugeEvent = {
+            timer: undefined,
+            value: 0,
+            min: 0,
+            max: 0
+        };
+    }
 
-                this.timeout_id = undefined;
-            }
-        },
+    let value = state.data.result[state.data.result.length - 1 - slot];
+    let min = (state.tmp.gaugeMin === null) ? NETDATA.commonMin.get(state) : state.tmp.gaugeMin;
+    let max = (state.tmp.gaugeMax === null) ? NETDATA.commonMax.get(state) : state.tmp.gaugeMax;
 
-        // sync all the visible charts to the given time
-        // this is to be called from the chart libraries
-        sync: function(state, t) {
-            if(NETDATA.options.current.sync_selection === true) {
-                if(NETDATA.options.debug.globalSelectionSync === true)
-                    console.log('globalSelectionSync.sync(' + state.id + ', ' + t.toString() + ')');
+    // make sure it is zero based
+    // but only if it has not been set by the user
+    if (state.tmp.gaugeMin === null && min > 0) {
+        min = 0;
+    }
+    if (state.tmp.gaugeMax === null && max < 0) {
+        max = 0;
+    }
 
-                this.setMaster(state);
+    state.tmp.gaugeEvent.value = value;
+    state.tmp.gaugeEvent.min = min;
+    state.tmp.gaugeEvent.max = max;
+    NETDATA.gaugeSetLabels(state, value, min, max);
 
-                if(t === this.last_t)
-                    return;
+    if (state.tmp.gaugeEvent.timer === undefined) {
+        NETDATA.gaugeAnimation(state, false);
 
-                this.last_t = t;
+        state.tmp.gaugeEvent.timer = NETDATA.timeout.set(function () {
+            state.tmp.gaugeEvent.timer = undefined;
+            NETDATA.gaugeSet(state, state.tmp.gaugeEvent.value, state.tmp.gaugeEvent.min, state.tmp.gaugeEvent.max);
+        }, 0);
+    }
 
-                if (state.foreign_element_selection !== null)
-                    state.foreign_element_selection.innerText = NETDATA.dateTime.localeDateString(t) + ' ' + NETDATA.dateTime.localeTimeString(t);
+    return true;
+};
 
-                if (this.timeout_id)
-                    NETDATA.timeout.clear(this.timeout_id);
+NETDATA.gaugeChartUpdate = function (state, data) {
+    let value, min, max;
 
-                this.timeout_id = NETDATA.timeout.set(this.__syncSlaves, 0);
-            }
+    if (NETDATA.globalPanAndZoom.isActive() || state.isAutoRefreshable() === false) {
+        NETDATA.gaugeSetLabels(state, null, null, null);
+        state.tmp.gauge_instance.set(0);
+    } else {
+        value = data.result[0];
+        min = (state.tmp.gaugeMin === null) ? NETDATA.commonMin.get(state) : state.tmp.gaugeMin;
+        max = (state.tmp.gaugeMax === null) ? NETDATA.commonMax.get(state) : state.tmp.gaugeMax;
+        if (value < min) {
+            min = value;
+        }
+        if (value > max) {
+            max = value;
         }
-    };
-
-    NETDATA.intersectionObserver = {
-        observer: null,
-        visible_targets: [],
-
-        options: {
-            root: null,
-            rootMargin: "0px",
-            threshold: null
-        },
 
-        enabled: function() {
-            return this.observer !== null;
-        },
+        // make sure it is zero based
+        // but only if it has not been set by the user
+        if (state.tmp.gaugeMin === null && min > 0) {
+            min = 0;
+        }
+        if (state.tmp.gaugeMax === null && max < 0) {
+            max = 0;
+        }
 
-        globalReset: function() {
-            if(this.observer !== null) {
-                this.visible_targets = [];
-                this.observer.disconnect();
-                this.init();
-            }
-        },
+        NETDATA.gaugeSet(state, value, min, max);
+        NETDATA.gaugeSetLabels(state, value, min, max);
+    }
 
-        targets: function() {
-            if(this.enabled() === true && this.visible_targets.length > 0)
-                return this.visible_targets;
-            else
-                return NETDATA.options.targets;
-        },
+    return true;
+};
+
+NETDATA.gaugeChartCreate = function (state, data) {
+    // let chart = $(state.element_chart);
+
+    let value = data.result[0];
+    let min = NETDATA.dataAttribute(state.element, 'gauge-min-value', null);
+    let max = NETDATA.dataAttribute(state.element, 'gauge-max-value', null);
+    // let adjust = NETDATA.dataAttribute(state.element, 'gauge-adjust', null);
+    let pointerColor = NETDATA.dataAttribute(state.element, 'gauge-pointer-color', NETDATA.themes.current.gauge_pointer);
+    let strokeColor = NETDATA.dataAttribute(state.element, 'gauge-stroke-color', NETDATA.themes.current.gauge_stroke);
+    let startColor = NETDATA.dataAttribute(state.element, 'gauge-start-color', state.chartCustomColors()[0]);
+    let stopColor = NETDATA.dataAttribute(state.element, 'gauge-stop-color', void 0);
+    let generateGradient = NETDATA.dataAttribute(state.element, 'gauge-generate-gradient', false);
+
+    if (min === null) {
+        min = NETDATA.commonMin.get(state);
+        state.tmp.gaugeMin = null;
+    } else {
+        state.tmp.gaugeMin = min;
+    }
 
-        switchChartVisibility: function() {
-            var old = this.__visibilityRatioOld;
+    if (max === null) {
+        max = NETDATA.commonMax.get(state);
+        state.tmp.gaugeMax = null;
+    } else {
+        state.tmp.gaugeMax = max;
+    }
 
-            if(old !== this.__visibilityRatio) {
-                if (old === 0 && this.__visibilityRatio > 0)
-                    this.unhideChart();
-                else if (old > 0 && this.__visibilityRatio === 0)
-                    this.hideChart();
+    // make sure it is zero based
+    // but only if it has not been set by the user
+    if (state.tmp.gaugeMin === null && min > 0) {
+        min = 0;
+    }
+    if (state.tmp.gaugeMax === null && max < 0) {
+        max = 0;
+    }
 
-                this.__visibilityRatioOld = this.__visibilityRatio;
-            }
+    let width = state.chartWidth(), height = state.chartHeight(); //, ratio = 1.5;
+    // console.log('gauge width: ' + width.toString() + ', height: ' + height.toString());
+    //switch(adjust) {
+    //  case 'width': width = height * ratio; break;
+    //  case 'height':
+    //  default: height = width / ratio; break;
+    //}
+    //state.element.style.width = width.toString() + 'px';
+    //state.element.style.height = height.toString() + 'px';
+
+    let lum_d = 0.05;
+
+    let options = {
+        lines: 12,                  // The number of lines to draw
+        angle: 0.14,                // The span of the gauge arc
+        lineWidth: 0.57,            // The line thickness
+        radiusScale: 1.0,           // Relative radius
+        pointer: {
+            length: 0.85,           // 0.9 The radius of the inner circle
+            strokeWidth: 0.045,     // The rotation offset
+            color: pointerColor     // Fill color
         },
+        limitMax: true,             // If false, the max value of the gauge will be updated if value surpass max
+        limitMin: true,             // If true, the min value of the gauge will be fixed unless you set it manually
+        colorStart: startColor,     // Colors
+        colorStop: stopColor,       // just experiment with them
+        strokeColor: strokeColor,   // to see which ones work best for you
+        generateGradient: (generateGradient === true), // gmosx: 
+        gradientType: 0,
+        highDpiSupport: true        // High resolution support
+    };
+
+    if (generateGradient.constructor === Array) {
+        // example options:
+        // data-gauge-generate-gradient="[0, 50, 100]"
+        // data-gauge-gradient-percent-color-0="#FFFFFF"
+        // data-gauge-gradient-percent-color-50="#999900"
+        // data-gauge-gradient-percent-color-100="#000000"
+
+        options.percentColors = [];
+        let len = generateGradient.length;
+        while (len--) {
+            let pcent = generateGradient[len];
+            let color = NETDATA.dataAttribute(state.element, 'gauge-gradient-percent-color-' + pcent.toString(), false);
+            if (color !== false) {
+                let a = [];
+                a[0] = pcent / 100;
+                a[1] = color;
+                options.percentColors.unshift(a);
+            }
+        }
+        if (options.percentColors.length === 0) {
+            delete options.percentColors;
+        }
+    } else if (generateGradient === false && NETDATA.themes.current.gauge_gradient) {
+        //noinspection PointlessArithmeticExpressionJS
+        options.percentColors = [
+            [0.0, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 0))],
+            [0.1, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 1))],
+            [0.2, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 2))],
+            [0.3, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 3))],
+            [0.4, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 4))],
+            [0.5, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 5))],
+            [0.6, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 6))],
+            [0.7, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 7))],
+            [0.8, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 8))],
+            [0.9, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 9))],
+            [1.0, NETDATA.colorLuminance(startColor, 0.0)]];
+    }
 
-        handler: function(entries, observer) {
-            entries.forEach(function(entry) {
-                var state = NETDATA.chartState(entry.target);
-
-                var idx;
-                if(entry.intersectionRatio > 0) {
-                    idx = NETDATA.intersectionObserver.visible_targets.indexOf(state);
-                    if(idx === -1) {
-                        if(NETDATA.scrollUp === true)
-                            NETDATA.intersectionObserver.visible_targets.push(state);
-                        else
-                            NETDATA.intersectionObserver.visible_targets.unshift(state);
-                    }
-                    else if(state.__visibilityRatio === 0)
-                        state.log("was not visible until now, but was already in visible_targets");
-                }
-                else {
-                    idx = NETDATA.intersectionObserver.visible_targets.indexOf(state);
-                    if(idx !== -1)
-                        NETDATA.intersectionObserver.visible_targets.splice(idx, 1);
-                    else if(state.__visibilityRatio > 0)
-                        state.log("was visible, but not found in visible_targets");
-                }
-
-                state.__visibilityRatio = entry.intersectionRatio;
-
-                if(NETDATA.options.current.async_on_scroll === false) {
-                    if(window.requestIdleCallback)
-                        window.requestIdleCallback(function() {
-                            NETDATA.intersectionObserver.switchChartVisibility.call(state);
-                        }, {timeout: 100});
-                    else
-                        NETDATA.intersectionObserver.switchChartVisibility.call(state);
-                }
-            });
-        },
+    state.tmp.gauge_canvas = document.createElement('canvas');
+    state.tmp.gauge_canvas.id = 'gauge-' + state.uuid + '-canvas';
+    state.tmp.gauge_canvas.className = 'gaugeChart';
+    state.tmp.gauge_canvas.width = width;
+    state.tmp.gauge_canvas.height = height;
+    state.element_chart.appendChild(state.tmp.gauge_canvas);
+
+    let valuefontsize = Math.floor(height / 5);
+    let valuetop = Math.round((height - valuefontsize) / 3.2);
+    state.tmp.gaugeChartLabel = document.createElement('span');
+    state.tmp.gaugeChartLabel.className = 'gaugeChartLabel';
+    state.tmp.gaugeChartLabel.style.fontSize = valuefontsize + 'px';
+    state.tmp.gaugeChartLabel.style.top = valuetop.toString() + 'px';
+    state.element_chart.appendChild(state.tmp.gaugeChartLabel);
+
+    let titlefontsize = Math.round(valuefontsize / 2.1);
+    let titletop = 0;
+    state.tmp.gaugeChartTitle = document.createElement('span');
+    state.tmp.gaugeChartTitle.className = 'gaugeChartTitle';
+    state.tmp.gaugeChartTitle.innerText = state.title;
+    state.tmp.gaugeChartTitle.style.fontSize = titlefontsize + 'px';
+    state.tmp.gaugeChartTitle.style.lineHeight = titlefontsize + 'px';
+    state.tmp.gaugeChartTitle.style.top = titletop.toString() + 'px';
+    state.element_chart.appendChild(state.tmp.gaugeChartTitle);
+
+    let unitfontsize = Math.round(titlefontsize * 0.9);
+    state.tmp.gaugeChartUnits = document.createElement('span');
+    state.tmp.gaugeChartUnits.className = 'gaugeChartUnits';
+    state.tmp.gaugeChartUnits.innerText = state.units_current;
+    state.tmp.gaugeChartUnits.style.fontSize = unitfontsize + 'px';
+    state.element_chart.appendChild(state.tmp.gaugeChartUnits);
+
+    state.tmp.gaugeChartMin = document.createElement('span');
+    state.tmp.gaugeChartMin.className = 'gaugeChartMin';
+    state.tmp.gaugeChartMin.style.fontSize = Math.round(valuefontsize * 0.75).toString() + 'px';
+    state.element_chart.appendChild(state.tmp.gaugeChartMin);
+
+    state.tmp.gaugeChartMax = document.createElement('span');
+    state.tmp.gaugeChartMax.className = 'gaugeChartMax';
+    state.tmp.gaugeChartMax.style.fontSize = Math.round(valuefontsize * 0.75).toString() + 'px';
+    state.element_chart.appendChild(state.tmp.gaugeChartMax);
+
+    // when we just re-create the chart
+    // do not animate the first update
+    let animate = true;
+    if (typeof state.tmp.gauge_instance !== 'undefined') {
+        animate = false;
+    }
 
-        observe: function(state) {
-            if(this.enabled() === true) {
-                state.__visibilityRatioOld = 0;
-                state.__visibilityRatio = 0;
-                this.observer.observe(state.element);
+    state.tmp.gauge_instance = new Gauge(state.tmp.gauge_canvas).setOptions(options); // create sexy gauge!
 
-                state.isVisible = function() {
-                    if(NETDATA.options.current.update_only_visible === false)
-                        return true;
+    state.tmp.___gaugeOld__ = {
+        value: value,
+        min: min,
+        max: max,
+        valueLabel: null,
+        minLabel: null,
+        maxLabel: null
+    };
 
-                    NETDATA.intersectionObserver.switchChartVisibility.call(this);
+    // we will always feed a percentage
+    state.tmp.gauge_instance.minValue = 0;
+    state.tmp.gauge_instance.maxValue = 100;
 
-                    return this.__visibilityRatio > 0;
-                }
-            }
-        },
+    NETDATA.gaugeAnimation(state, animate);
+    NETDATA.gaugeSet(state, value, min, max);
+    NETDATA.gaugeSetLabels(state, value, min, max);
+    NETDATA.gaugeAnimation(state, true);
 
-        init: function() {
-            if(typeof netdataIntersectionObserver === 'undefined' || netdataIntersectionObserver === true) {
-                try {
-                    this.observer = new IntersectionObserver(this.handler, this.options);
-                }
-                catch (e) {
-                    console.log("IntersectionObserver is not supported on this browser");
-                    this.observer = null;
-                }
-            }
-            //else {
-            //    console.log("IntersectionObserver is disabled");
-            //}
+    state.legendSetUnitsString = function (units) {
+        if (typeof state.tmp.gaugeChartUnits !== 'undefined' && state.tmp.units !== units) {
+            state.tmp.gaugeChartUnits.innerText = units;
+            state.tmp.___gaugeOld__.valueLabel = null;
+            state.tmp.___gaugeOld__.minLabel = null;
+            state.tmp.___gaugeOld__.maxLabel = null;
+            state.tmp.units = units;
+        }
+    };
+    state.legendShowUndefined = function () {
+        if (typeof state.tmp.gauge_instance !== 'undefined') {
+            NETDATA.gaugeClearSelection(state);
         }
     };
-    NETDATA.intersectionObserver.init();
-
-    // ----------------------------------------------------------------------------------------------------------------
-    // Our state object, where all per-chart values are stored
-
-    var chartState = function(element) {
-        this.element = element;
-
-        // IMPORTANT:
-        // all private functions should use 'that', instead of 'this'
-        var that = this;
 
-        // ============================================================================================================
-        // ERROR HANDLING
+    return true;
+};
+// ----------------------------------------------------------------------------------------------------------------
 
-        /* error() - private
-         * show an error instead of the chart
-         */
-        var error = function(msg) {
-            var ret = true;
+NETDATA.easypiechartPercentFromValueMinMax = function (state, value, min, max) {
+    if (typeof value !== 'number') {
+        value = 0;
+    }
+    if (typeof min !== 'number') {
+        min = 0;
+    }
+    if (typeof max !== 'number') {
+        max = 0;
+    }
 
-            if(typeof netdataErrorCallback === 'function') {
-                ret = netdataErrorCallback('chart', that.id, msg);
-            }
+    if (min > max) {
+        let t = min;
+        min = max;
+        max = t;
+    }
 
-            if(ret) {
-                that.element.innerHTML = that.id + ': ' + msg;
-                that.enabled = false;
-                that.current = that.pan;
-            }
-        };
+    if (min > value) {
+        min = value;
+    }
+    if (max < value) {
+        max = value;
+    }
 
-        // console logging
-        this.log = function(msg) {
-            console.log(this.id + ' (' + this.library_name + ' ' + this.uuid + '): ' + msg);
-        };
+    state.legendFormatValueDecimalsFromMinMax(min, max);
 
+    if (state.tmp.easyPieChartMin === null && min > 0) {
+        min = 0;
+    }
+    if (state.tmp.easyPieChartMax === null && max < 0) {
+        max = 0;
+    }
 
-        // ============================================================================================================
-        // EARLY INITIALIZATION
+    let pcent;
+
+    if (min < 0 && max > 0) {
+        // it is both positive and negative
+        // zero at the top center of the chart
+        max = (-min > max) ? -min : max;
+        pcent = Math.round(value * 100 / max);
+    } else if (value >= 0 && min >= 0 && max >= 0) {
+        // clockwise
+        pcent = Math.round((value - min) * 100 / (max - min));
+        if (pcent === 0) {
+            pcent = 0.1;
+        }
+    } else {
+        // counter clockwise
+        pcent = Math.round((value - max) * 100 / (max - min));
+        if (pcent === 0) {
+            pcent = -0.1;
+        }
+    }
 
-        // These are variables that should exist even if the chart is never to be rendered.
-        // Be careful what you add here - there may be thousands of charts on the page.
+    return pcent;
+};
 
-        // GUID - a unique identifier for the chart
-        this.uuid = NETDATA.guid();
+// ----------------------------------------------------------------------------------------------------------------
+// easy-pie-chart
 
-        // string - the name of chart
-        this.id = NETDATA.dataAttribute(this.element, 'netdata', undefined);
-        if(typeof this.id === 'undefined') {
-            error("netdata elements need data-netdata");
-            return;
+NETDATA.easypiechartInitialize = function (callback) {
+    if (typeof netdataNoEasyPieChart === 'undefined' || !netdataNoEasyPieChart) {
+        $.ajax({
+            url: NETDATA.easypiechart_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function () {
+                NETDATA.registerChartLibrary('easypiechart', NETDATA.easypiechart_js);
+            })
+            .fail(function () {
+                NETDATA.chartLibraries.easypiechart.enabled = false;
+                NETDATA.error(100, NETDATA.easypiechart_js);
+            })
+            .always(function () {
+                if (typeof callback === "function") {
+                    return callback();
+                }
+            })
+    } else {
+        NETDATA.chartLibraries.easypiechart.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
         }
+    }
+};
 
-        // string - the key for localStorage settings
-        this.settings_id = NETDATA.dataAttribute(this.element, 'id', null);
-
-        // the user given dimensions of the element
-        this.width = NETDATA.dataAttribute(this.element, 'width', NETDATA.chartDefaults.width);
-        this.height = NETDATA.dataAttribute(this.element, 'height', NETDATA.chartDefaults.height);
-        this.height_original = this.height;
+NETDATA.easypiechartClearSelection = function (state, force) {
+    if (typeof state.tmp.easyPieChartEvent !== 'undefined' && typeof state.tmp.easyPieChartEvent.timer !== 'undefined') {
+        NETDATA.timeout.clear(state.tmp.easyPieChartEvent.timer);
+        state.tmp.easyPieChartEvent.timer = undefined;
+    }
 
-        if(this.settings_id !== null) {
-            this.height = NETDATA.localStorageGet('chart_heights.' + this.settings_id, this.height, function(height) {
-                // this is the callback that will be called
-                // if and when the user resets all localStorage variables
-                // to their defaults
+    if (state.isAutoRefreshable() && state.data !== null && force !== true) {
+        NETDATA.easypiechartChartUpdate(state, state.data);
+    }
+    else {
+        state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(null);
+        state.tmp.easyPieChart_instance.update(0);
+    }
+    state.tmp.easyPieChart_instance.enableAnimation();
 
-                resizeChartToHeight(height);
-            });
-        }
+    return true;
+};
 
-        // the chart library requested by the user
-        this.library_name = NETDATA.dataAttribute(this.element, 'chart-library', NETDATA.chartDefaults.library);
+NETDATA.easypiechartSetSelection = function (state, t) {
+    if (state.timeIsVisible(t) !== true) {
+        return NETDATA.easypiechartClearSelection(state, true);
+    }
 
-        // check the requested library is available
-        // we don't initialize it here - it will be initialized when
-        // this chart will be first used
-        if(typeof NETDATA.chartLibraries[this.library_name] === 'undefined') {
-            NETDATA.error(402, this.library_name);
-            error('chart library "' + this.library_name + '" is not found');
-            this.enabled = false;
-        }
-        else if(NETDATA.chartLibraries[this.library_name].enabled === false) {
-            NETDATA.error(403, this.library_name);
-            error('chart library "' + this.library_name + '" is not enabled');
-            this.enabled = false;
-        }
-        else
-            this.library = NETDATA.chartLibraries[this.library_name];
+    let slot = state.calculateRowForTime(t);
+    if (slot < 0 || slot >= state.data.result.length) {
+        return NETDATA.easypiechartClearSelection(state, true);
+    }
 
-        this.auto = {
-            name: 'auto',
-            autorefresh: true,
-            force_update_at: 0, // the timestamp to force the update at
-            force_before_ms: null,
-            force_after_ms: null
-        };
-        this.pan = {
-            name: 'pan',
-            autorefresh: false,
-            force_update_at: 0, // the timestamp to force the update at
-            force_before_ms: null,
-            force_after_ms: null
-        };
-        this.zoom = {
-            name: 'zoom',
-            autorefresh: false,
-            force_update_at: 0, // the timestamp to force the update at
-            force_before_ms: null,
-            force_after_ms: null
+    if (typeof state.tmp.easyPieChartEvent === 'undefined') {
+        state.tmp.easyPieChartEvent = {
+            timer: undefined,
+            value: 0,
+            pcent: 0
         };
+    }
 
-        // this is a pointer to one of the sub-classes below
-        // auto, pan, zoom
-        this.current = this.auto;
-
-        this.running = false;                       // boolean - true when the chart is being refreshed now
-        this.enabled = true;                        // boolean - is the chart enabled for refresh?
-
-        this.force_update_every = null;             // number - overwrite the visualization update frequency of the chart
-
-        this.tmp = {};
-
-        this.foreign_element_before = null;
-        this.foreign_element_after = null;
-        this.foreign_element_duration = null;
-        this.foreign_element_update_every = null;
-        this.foreign_element_selection = null;
-
-        // ============================================================================================================
-        // PRIVATE FUNCTIONS
-
-        // reset the runtime status variables to their defaults
-        var runtimeInit = function() {
-            that.paused = false;                        // boolean - is the chart paused for any reason?
-            that.selected = false;                      // boolean - is the chart shown a selection?
-
-            that.chart_created = false;                 // boolean - is the library.create() been called?
-            that.dom_created = false;                   // boolean - is the chart DOM been created?
-            that.fetching_data = false;                 // boolean - true while we fetch data via ajax
-
-            that.updates_counter = 0;                   // numeric - the number of refreshes made so far
-            that.updates_since_last_unhide = 0;         // numeric - the number of refreshes made since the last time the chart was unhidden
-            that.updates_since_last_creation = 0;       // numeric - the number of refreshes made since the last time the chart was created
-
-            that.tm = {
-                last_initialized: 0,                    // milliseconds - the timestamp it was last initialized
-                last_dom_created: 0,                    // milliseconds - the timestamp its DOM was last created
-                last_mode_switch: 0,                    // milliseconds - the timestamp it switched modes
-
-                last_info_downloaded: 0,                // milliseconds - the timestamp we downloaded the chart
-                last_updated: 0,                        // the timestamp the chart last updated with data
-                pan_and_zoom_seq: 0,                    // the sequence number of the global synchronization
-                                                        // between chart.
-                                                        // Used with NETDATA.globalPanAndZoom.seq
-                last_visible_check: 0,                  // the time we last checked if it is visible
-                last_resized: 0,                        // the time the chart was resized
-                last_hidden: 0,                         // the time the chart was hidden
-                last_unhidden: 0,                       // the time the chart was unhidden
-                last_autorefreshed: 0                   // the time the chart was last refreshed
-            };
+    let value = state.data.result[state.data.result.length - 1 - slot];
+    let min = (state.tmp.easyPieChartMin === null) ? NETDATA.commonMin.get(state) : state.tmp.easyPieChartMin;
+    let max = (state.tmp.easyPieChartMax === null) ? NETDATA.commonMax.get(state) : state.tmp.easyPieChartMax;
+    let pcent = NETDATA.easypiechartPercentFromValueMinMax(state, value, min, max);
 
-            that.data = null;                           // the last data as downloaded from the netdata server
-            that.data_url = 'invalid://';               // string - the last url used to update the chart
-            that.data_points = 0;                       // number - the number of points returned from netdata
-            that.data_after = 0;                        // milliseconds - the first timestamp of the data
-            that.data_before = 0;                       // milliseconds - the last timestamp of the data
-            that.data_update_every = 0;                 // milliseconds - the frequency to update the data
+    state.tmp.easyPieChartEvent.value = value;
+    state.tmp.easyPieChartEvent.pcent = pcent;
+    state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(value);
 
-            that.tmp = {};                              // members that can be destroyed to save memory
-        };
+    if (state.tmp.easyPieChartEvent.timer === undefined) {
+        state.tmp.easyPieChart_instance.disableAnimation();
 
-        // initialize all the variables that are required for the chart to be rendered
-        var lateInitialization = function() {
-            if(typeof that.host !== 'undefined')
-                return;
+        state.tmp.easyPieChartEvent.timer = NETDATA.timeout.set(function () {
+            state.tmp.easyPieChartEvent.timer = undefined;
+            state.tmp.easyPieChart_instance.update(state.tmp.easyPieChartEvent.pcent);
+        }, 0);
+    }
 
-            // string - the netdata server URL, without any path
-            that.host = NETDATA.dataAttribute(that.element, 'host', NETDATA.serverDefault);
+    return true;
+};
 
-            // make sure the host does not end with /
-            // all netdata API requests use absolute paths
-            while(that.host.slice(-1) === '/')
-                that.host = that.host.substring(0, that.host.length - 1);
+NETDATA.easypiechartChartUpdate = function (state, data) {
+    let value, min, max, pcent;
 
-            // string - the grouping method requested by the user
-            that.method = NETDATA.dataAttribute(that.element, 'method', NETDATA.chartDefaults.method);
-            that.gtime = NETDATA.dataAttribute(that.element, 'gtime', 0);
+    if (NETDATA.globalPanAndZoom.isActive() || state.isAutoRefreshable() === false) {
+        value = null;
+        pcent = 0;
+    }
+    else {
+        value = data.result[0];
+        min = (state.tmp.easyPieChartMin === null) ? NETDATA.commonMin.get(state) : state.tmp.easyPieChartMin;
+        max = (state.tmp.easyPieChartMax === null) ? NETDATA.commonMax.get(state) : state.tmp.easyPieChartMax;
+        pcent = NETDATA.easypiechartPercentFromValueMinMax(state, value, min, max);
+    }
 
-            // the time-range requested by the user
-            that.after = NETDATA.dataAttribute(that.element, 'after', NETDATA.chartDefaults.after);
-            that.before = NETDATA.dataAttribute(that.element, 'before', NETDATA.chartDefaults.before);
+    state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(value);
+    state.tmp.easyPieChart_instance.update(pcent);
+    return true;
+};
 
-            // the pixels per point requested by the user
-            that.pixels_per_point = NETDATA.dataAttribute(that.element, 'pixels-per-point', 1);
-            that.points = NETDATA.dataAttribute(that.element, 'points', null);
+NETDATA.easypiechartChartCreate = function (state, data) {
+    let chart = $(state.element_chart);
 
-            // the forced update_every
-            that.force_update_every = NETDATA.dataAttribute(that.element, 'update-every', null);
-            if(typeof that.force_update_every !== 'number' || that.force_update_every <= 1) {
-                if(that.force_update_every !== null)
-                    that.log('ignoring invalid value of property data-update-every');
+    let value = data.result[0];
+    let min = NETDATA.dataAttribute(state.element, 'easypiechart-min-value', null);
+    let max = NETDATA.dataAttribute(state.element, 'easypiechart-max-value', null);
 
-                that.force_update_every = null;
-            }
-            else
-                that.force_update_every *= 1000;
+    if (min === null) {
+        min = NETDATA.commonMin.get(state);
+        state.tmp.easyPieChartMin = null;
+    }
+    else {
+        state.tmp.easyPieChartMin = min;
+    }
 
-            // the dimensions requested by the user
-            that.dimensions = NETDATA.encodeURIComponent(NETDATA.dataAttribute(that.element, 'dimensions', null));
+    if (max === null) {
+        max = NETDATA.commonMax.get(state);
+        state.tmp.easyPieChartMax = null;
+    }
+    else {
+        state.tmp.easyPieChartMax = max;
+    }
 
-            that.title = NETDATA.dataAttribute(that.element, 'title', null);    // the title of the chart
-            that.units = NETDATA.dataAttribute(that.element, 'units', null);    // the units of the chart dimensions
-            that.units_desired = NETDATA.dataAttribute(that.element, 'desired-units', NETDATA.options.current.units); // the units of the chart dimensions
-            that.units_current = that.units;
-            that.units_common = NETDATA.dataAttribute(that.element, 'common-units', null);
+    let size = state.chartWidth();
+    let stroke = Math.floor(size / 22);
+    if (stroke < 3) {
+        stroke = 2;
+    }
 
-            // additional options to pass to netdata
-            that.append_options = NETDATA.encodeURIComponent(NETDATA.dataAttribute(that.element, 'append-options', null));
+    let valuefontsize = Math.floor((size * 2 / 3) / 5);
+    let valuetop = Math.round((size - valuefontsize - (size / 40)) / 2);
+    state.tmp.easyPieChartLabel = document.createElement('span');
+    state.tmp.easyPieChartLabel.className = 'easyPieChartLabel';
+    state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(value);
+    state.tmp.easyPieChartLabel.style.fontSize = valuefontsize + 'px';
+    state.tmp.easyPieChartLabel.style.top = valuetop.toString() + 'px';
+    state.element_chart.appendChild(state.tmp.easyPieChartLabel);
+
+    let titlefontsize = Math.round(valuefontsize * 1.6 / 3);
+    let titletop = Math.round(valuetop - (titlefontsize * 2) - (size / 40));
+    state.tmp.easyPieChartTitle = document.createElement('span');
+    state.tmp.easyPieChartTitle.className = 'easyPieChartTitle';
+    state.tmp.easyPieChartTitle.innerText = state.title;
+    state.tmp.easyPieChartTitle.style.fontSize = titlefontsize + 'px';
+    state.tmp.easyPieChartTitle.style.lineHeight = titlefontsize + 'px';
+    state.tmp.easyPieChartTitle.style.top = titletop.toString() + 'px';
+    state.element_chart.appendChild(state.tmp.easyPieChartTitle);
+
+    let unitfontsize = Math.round(titlefontsize * 0.9);
+    let unittop = Math.round(valuetop + (valuefontsize + unitfontsize) + (size / 40));
+    state.tmp.easyPieChartUnits = document.createElement('span');
+    state.tmp.easyPieChartUnits.className = 'easyPieChartUnits';
+    state.tmp.easyPieChartUnits.innerText = state.units_current;
+    state.tmp.easyPieChartUnits.style.fontSize = unitfontsize + 'px';
+    state.tmp.easyPieChartUnits.style.top = unittop.toString() + 'px';
+    state.element_chart.appendChild(state.tmp.easyPieChartUnits);
+
+    let barColor = NETDATA.dataAttribute(state.element, 'easypiechart-barcolor', undefined);
+    if (typeof barColor === 'undefined' || barColor === null) {
+        barColor = state.chartCustomColors()[0];
+    } else {
+        // <div ... data-easypiechart-barcolor="(function(percent){return(percent < 50 ? '#5cb85c' : percent < 85 ? '#f0ad4e' : '#cb3935');})" ...></div>
+        let tmp = eval(barColor);
+        if (typeof tmp === 'function') {
+            barColor = tmp;
+        }
+    }
 
-            // override options to pass to netdata
-            that.override_options = NETDATA.encodeURIComponent(NETDATA.dataAttribute(that.element, 'override-options', null));
+    let pcent = NETDATA.easypiechartPercentFromValueMinMax(state, value, min, max);
+    chart.data('data-percent', pcent);
+
+    chart.easyPieChart({
+        barColor: barColor,
+        trackColor: NETDATA.dataAttribute(state.element, 'easypiechart-trackcolor', NETDATA.themes.current.easypiechart_track),
+        scaleColor: NETDATA.dataAttribute(state.element, 'easypiechart-scalecolor', NETDATA.themes.current.easypiechart_scale),
+        scaleLength: NETDATA.dataAttribute(state.element, 'easypiechart-scalelength', 5),
+        lineCap: NETDATA.dataAttribute(state.element, 'easypiechart-linecap', 'round'),
+        lineWidth: NETDATA.dataAttribute(state.element, 'easypiechart-linewidth', stroke),
+        trackWidth: NETDATA.dataAttribute(state.element, 'easypiechart-trackwidth', undefined),
+        size: NETDATA.dataAttribute(state.element, 'easypiechart-size', size),
+        rotate: NETDATA.dataAttribute(state.element, 'easypiechart-rotate', 0),
+        animate: NETDATA.dataAttribute(state.element, 'easypiechart-animate', {duration: 500, enabled: true}),
+        easing: NETDATA.dataAttribute(state.element, 'easypiechart-easing', undefined)
+    });
 
-            that.debug = NETDATA.dataAttributeBoolean(that.element, 'debug', false);
+    // when we just re-create the chart
+    // do not animate the first update
+    let animate = true;
+    if (typeof state.tmp.easyPieChart_instance !== 'undefined') {
+        animate = false;
+    }
 
-            that.value_decimal_detail = -1;
-            var d = NETDATA.dataAttribute(that.element, 'decimal-digits', -1);
-            if(typeof d === 'number')
-                that.value_decimal_detail = d;
-            else if(typeof d !== 'undefined')
-                that.log('ignoring decimal-digits value: ' + d.toString());
+    state.tmp.easyPieChart_instance = chart.data('easyPieChart');
+    if (animate === false) {
+        state.tmp.easyPieChart_instance.disableAnimation();
+    }
+    state.tmp.easyPieChart_instance.update(pcent);
+    if (animate === false) {
+        state.tmp.easyPieChart_instance.enableAnimation();
+    }
 
-            // if we need to report the rendering speed
-            // find the element that needs to be updated
-            var refresh_dt_element_name = NETDATA.dataAttribute(that.element, 'dt-element-name', null); // string - the element to print refresh_dt_ms
+    state.legendSetUnitsString = function (units) {
+        if (typeof state.tmp.easyPieChartUnits !== 'undefined' && state.tmp.units !== units) {
+            state.tmp.easyPieChartUnits.innerText = units;
+            state.tmp.units = units;
+        }
+    };
+    state.legendShowUndefined = function () {
+        if (typeof state.tmp.easyPieChart_instance !== 'undefined') {
+            NETDATA.easypiechartClearSelection(state);
+        }
+    };
 
-            if(refresh_dt_element_name !== null) {
-                that.refresh_dt_element = document.getElementById(refresh_dt_element_name) || null;
-            }
-            else
-                that.refresh_dt_element = null;
-
-            that.dimensions_visibility = new dimensionsVisibility(that);
-
-            that.netdata_first = 0;                     // milliseconds - the first timestamp in netdata
-            that.netdata_last = 0;                      // milliseconds - the last timestamp in netdata
-            that.requested_after = null;                // milliseconds - the timestamp of the request after param
-            that.requested_before = null;               // milliseconds - the timestamp of the request before param
-            that.requested_padding = null;
-            that.view_after = 0;
-            that.view_before = 0;
-
-            that.refresh_dt_ms = 0;                     // milliseconds - the time the last refresh took
-
-            // how many retries we have made to load chart data from the server
-            that.retries_on_data_failures = 0;
-
-            // color management
-            that.colors = null;
-            that.colors_assigned = null;
-            that.colors_available = null;
-            that.colors_custom = null;
-
-            that.element_message = null; // the element already created by the user
-            that.element_chart = null; // the element with the chart
-            that.element_legend = null; // the element with the legend of the chart (if created by us)
-            that.element_legend_childs = {
-                content: null,
-                hidden: null,
-                title_date: null,
-                title_time: null,
-                title_units: null,
-                perfect_scroller: null, // the container to apply perfect scroller to
-                series: null
-            };
+    return true;
+};
 
-            that.chart_url = null;                      // string - the url to download chart info
-            that.chart = null;                          // object - the chart as downloaded from the server
+// d3pie
 
-            function get_foreign_element_by_id(opt) {
-                var id = NETDATA.dataAttribute(that.element, opt, null);
-                if(id === null) {
-                    //that.log('option "' + opt + '" is undefined');
-                    return null;
-                }
+NETDATA.d3pieInitialize = function (callback) {
+    if (typeof netdataNoD3pie === 'undefined' || !netdataNoD3pie) {
 
-                var el = document.getElementById(id);
-                if(typeof el === 'undefined') {
-                    that.log('cannot find an element with name "' + id.toString() + '"');
-                    return null;
+        // d3pie requires D3
+        if (!NETDATA.chartLibraries.d3.initialized) {
+            if (NETDATA.chartLibraries.d3.enabled) {
+                NETDATA.d3Initialize(function () {
+                    NETDATA.d3pieInitialize(callback);
+                });
+            } else {
+                NETDATA.chartLibraries.d3pie.enabled = false;
+                if (typeof callback === "function") {
+                    return callback();
                 }
-
-                return el;
             }
+        } else {
+            $.ajax({
+                url: NETDATA.d3pie_js,
+                cache: true,
+                dataType: "script",
+                xhrFields: {withCredentials: true} // required for the cookie
+            })
+                .done(function () {
+                    NETDATA.registerChartLibrary('d3pie', NETDATA.d3pie_js);
+                })
+                .fail(function () {
+                    NETDATA.chartLibraries.d3pie.enabled = false;
+                    NETDATA.error(100, NETDATA.d3pie_js);
+                })
+                .always(function () {
+                    if (typeof callback === "function") {
+                        return callback();
+                    }
+                });
+        }
+    } else {
+        NETDATA.chartLibraries.d3pie.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
+        }
+    }
+};
+
+NETDATA.d3pieSetContent = function (state, data, index) {
+    state.legendFormatValueDecimalsFromMinMax(
+        data.min,
+        data.max
+    );
+
+    let content = [];
+    let colors = state.chartColors();
+    let len = data.result.labels.length;
+    for (let i = 1; i < len; i++) {
+        let label = data.result.labels[i];
+        let value = data.result.data[index][label];
+        let color = colors[i - 1];
+
+        if (value !== null && value > 0) {
+            content.push({
+                label: label,
+                value: value,
+                color: color
+            });
+        }
+    }
 
-            that.foreign_element_before = get_foreign_element_by_id('show-before-at');
-            that.foreign_element_after = get_foreign_element_by_id('show-after-at');
-            that.foreign_element_duration = get_foreign_element_by_id('show-duration-at');
-            that.foreign_element_update_every = get_foreign_element_by_id('show-update-every-at');
-            that.foreign_element_selection = get_foreign_element_by_id('show-selection-at');
-        };
-
-        var destroyDOM = function() {
-            if(that.enabled === false) return;
-
-            if(that.debug === true)
-                that.log('destroyDOM()');
-
-            // that.element.className = 'netdata-message icon';
-            // that.element.innerHTML = '<i class="fas fa-sync"></i> netdata';
-            that.element.innerHTML = '';
-            that.element_message = null;
-            that.element_legend = null;
-            that.element_chart = null;
-            that.element_legend_childs.series = null;
-
-            that.chart_created = false;
-            that.dom_created = false;
-
-            that.tm.last_resized = 0;
-            that.tm.last_dom_created = 0;
-        };
+    if (content.length === 0) {
+        content.push({
+            label: 'no data',
+            value: 100,
+            color: '#666666'
+        });
+    }
 
-        var createDOM = function() {
-            if(that.enabled === false) return;
-            lateInitialization();
+    state.tmp.d3pie_last_slot = index;
+    return content;
+};
 
-            destroyDOM();
+NETDATA.d3pieDateRange = function (state, data, index) {
+    let dt = Math.round((data.before - data.after + 1) / data.points);
+    let dt_str = NETDATA.seconds4human(dt);
 
-            if(that.debug === true)
-                that.log('createDOM()');
+    let before = data.result.data[index].time;
+    let after = before - (dt * 1000);
 
-            that.element_message = document.createElement('div');
-            that.element_message.className = 'netdata-message icon hidden';
-            that.element.appendChild(that.element_message);
+    let d1 = NETDATA.dateTime.localeDateString(after);
+    let t1 = NETDATA.dateTime.localeTimeString(after);
+    let d2 = NETDATA.dateTime.localeDateString(before);
+    let t2 = NETDATA.dateTime.localeTimeString(before);
 
-            that.dom_created = true;
-            that.chart_created = false;
+    if (d1 === d2) {
+        return d1 + ' ' + t1 + ' to ' + t2 + ', ' + dt_str;
+    }
 
-            that.tm.last_dom_created =
-                that.tm.last_resized = Date.now();
+    return d1 + ' ' + t1 + ' to ' + d2 + ' ' + t2 + ', ' + dt_str;
+};
 
-            showLoading();
-        };
+NETDATA.d3pieSetSelection = function (state, t) {
+    if (state.timeIsVisible(t) !== true) {
+        return NETDATA.d3pieClearSelection(state, true);
+    }
 
-        var initDOM = function() {
-            that.element.className = that.library.container_class(that);
+    let slot = state.calculateRowForTime(t);
+    slot = state.data.result.data.length - slot - 1;
 
-            if(typeof(that.width) === 'string')
-                that.element.style.width = that.width;
-            else if(typeof(that.width) === 'number')
-                that.element.style.width = that.width.toString() + 'px';
+    if (slot < 0 || slot >= state.data.result.length) {
+        return NETDATA.d3pieClearSelection(state, true);
+    }
 
-            if(typeof(that.library.aspect_ratio) === 'undefined') {
-                if(typeof(that.height) === 'string')
-                    that.element.style.height = that.height;
-                else if(typeof(that.height) === 'number')
-                    that.element.style.height = that.height.toString() + 'px';
-            }
+    if (state.tmp.d3pie_last_slot === slot) {
+        // we already show this slot, don't do anything
+        return true;
+    }
 
-            if(NETDATA.chartDefaults.min_width !== null)
-                that.element.style.min_width = NETDATA.chartDefaults.min_width;
-        };
+    if (state.tmp.d3pie_timer === undefined) {
+        state.tmp.d3pie_timer = NETDATA.timeout.set(function () {
+            state.tmp.d3pie_timer = undefined;
+            NETDATA.d3pieChange(state, NETDATA.d3pieSetContent(state, state.data, slot), NETDATA.d3pieDateRange(state, state.data, slot));
+        }, 0);
+    }
 
-        var invisibleSearchableText = function() {
-            return '<span style="position:absolute; opacity: 0; width: 0px;">' + that.id + '</span>';
-        };
+    return true;
+};
 
-        /* init() private
-         * initialize state variables
-         * destroy all (possibly) created state elements
-         * create the basic DOM for a chart
-         */
-        var init = function(opt) {
-            if(that.enabled === false) return;
+NETDATA.d3pieClearSelection = function (state, force) {
+    if (typeof state.tmp.d3pie_timer !== 'undefined') {
+        NETDATA.timeout.clear(state.tmp.d3pie_timer);
+        state.tmp.d3pie_timer = undefined;
+    }
 
-            runtimeInit();
-            that.element.innerHTML = invisibleSearchableText();
+    if (state.isAutoRefreshable() && state.data !== null && force !== true) {
+        NETDATA.d3pieChartUpdate(state, state.data);
+    } else {
+        if (state.tmp.d3pie_last_slot !== -1) {
+            state.tmp.d3pie_last_slot = -1;
+            NETDATA.d3pieChange(state, [{label: 'no data', value: 1, color: '#666666'}], 'no data available');
+        }
+    }
 
-            that.tm.last_initialized = Date.now();
-            that.setMode('auto');
+    return true;
+};
 
-            if(opt !== 'fast') {
-                if (that.isVisible(true) || opt === 'force')
-                    createDOM();
-            }
-        };
+NETDATA.d3pieChange = function (state, content, footer) {
+    if (state.d3pie_forced_subtitle === null) {
+        //state.d3pie_instance.updateProp("header.subtitle.text", state.units_current);
+        state.d3pie_instance.options.header.subtitle.text = state.units_current;
+    }
 
-        var maxMessageFontSize = function() {
-            var screenHeight = screen.height;
-            var el = that.element;
+    if (state.d3pie_forced_footer === null) {
+        //state.d3pie_instance.updateProp("footer.text", footer);
+        state.d3pie_instance.options.footer.text = footer;
+    }
 
-            // normally we want a font size, as tall as the element
-            var h = el.clientHeight;
+    //state.d3pie_instance.updateProp("data.content", content);
+    state.d3pie_instance.options.data.content = content;
+    state.d3pie_instance.destroy();
+    state.d3pie_instance.recreate();
+    return true;
+};
 
-            // but give it some air, 20% let's say, or 5 pixels min
-            var lost = Math.max(h * 0.2, 5);
-            h -= lost;
+NETDATA.d3pieChartUpdate = function (state, data) {
+    return NETDATA.d3pieChange(state, NETDATA.d3pieSetContent(state, data, 0), NETDATA.d3pieDateRange(state, data, 0));
+};
 
-            // center the text, vertically
-            var paddingTop = (lost - 5) / 2;
+NETDATA.d3pieChartCreate = function (state, data) {
 
-            // but check the width too
-            // it should fit 10 characters in it
-            var w = el.clientWidth / 10;
-            if(h > w) {
-                paddingTop += (h - w) / 2;
-                h = w;
-            }
+    state.element_chart.id = 'd3pie-' + state.uuid;
+    // console.log('id = ' + state.element_chart.id);
 
-            // and don't make it too huge
-            // 5% of the screen size is good
-            if(h > screenHeight / 20) {
-                paddingTop += (h - (screenHeight / 20)) / 2;
-                h = screenHeight / 20;
-            }
+    let content = NETDATA.d3pieSetContent(state, data, 0);
 
-            // set it
-            that.element_message.style.fontSize = h.toString() + 'px';
-            that.element_message.style.paddingTop = paddingTop.toString() + 'px';
-        };
+    state.d3pie_forced_title = NETDATA.dataAttribute(state.element, 'd3pie-title', null);
+    state.d3pie_forced_subtitle = NETDATA.dataAttribute(state.element, 'd3pie-subtitle', null);
+    state.d3pie_forced_footer = NETDATA.dataAttribute(state.element, 'd3pie-footer', null);
 
-        var showMessageIcon = function(icon) {
-            that.element_message.innerHTML = icon;
-            maxMessageFontSize();
-            $(that.element_message).removeClass('hidden');
-            that.tmp.___messageHidden___ = undefined;
-        };
+    state.d3pie_options = {
+        header: {
+            title: {
+                text: (state.d3pie_forced_title !== null) ? state.d3pie_forced_title : state.title,
+                color: NETDATA.dataAttribute(state.element, 'd3pie-title-color', NETDATA.themes.current.d3pie.title),
+                fontSize: NETDATA.dataAttribute(state.element, 'd3pie-title-fontsize', 12),
+                fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-title-fontweight', "bold"),
+                font: NETDATA.dataAttribute(state.element, 'd3pie-title-font', "arial")
+            },
+            subtitle: {
+                text: (state.d3pie_forced_subtitle !== null) ? state.d3pie_forced_subtitle : state.units_current,
+                color: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-color', NETDATA.themes.current.d3pie.subtitle),
+                fontSize: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-fontsize', 10),
+                fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-fontweight', "normal"),
+                font: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-font', "arial")
+            },
+            titleSubtitlePadding: 1
+        },
+        footer: {
+            text: (state.d3pie_forced_footer !== null) ? state.d3pie_forced_footer : NETDATA.d3pieDateRange(state, data, 0),
+            color: NETDATA.dataAttribute(state.element, 'd3pie-footer-color', NETDATA.themes.current.d3pie.footer),
+            fontSize: NETDATA.dataAttribute(state.element, 'd3pie-footer-fontsize', 9),
+            fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-footer-fontweight', "bold"),
+            font: NETDATA.dataAttribute(state.element, 'd3pie-footer-font', "arial"),
+            location: NETDATA.dataAttribute(state.element, 'd3pie-footer-location', "bottom-center") // bottom-left, bottom-center, bottom-right
+        },
+        size: {
+            canvasHeight: state.chartHeight(),
+            canvasWidth: state.chartWidth(),
+            pieInnerRadius: NETDATA.dataAttribute(state.element, 'd3pie-pieinnerradius', "45%"),
+            pieOuterRadius: NETDATA.dataAttribute(state.element, 'd3pie-pieouterradius', "80%")
+        },
+        data: {
+            // none, random, value-asc, value-desc, label-asc, label-desc
+            sortOrder: NETDATA.dataAttribute(state.element, 'd3pie-sortorder', "value-desc"),
+            smallSegmentGrouping: {
+                enabled: NETDATA.dataAttributeBoolean(state.element, "d3pie-smallsegmentgrouping-enabled", false),
+                value: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-value', 1),
+                // percentage, value
+                valueType: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-valuetype', "percentage"),
+                label: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-label', "other"),
+                color: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-color', NETDATA.themes.current.d3pie.other)
+            },
 
-        var hideMessage = function() {
-            if(typeof that.tmp.___messageHidden___ === 'undefined') {
-                that.tmp.___messageHidden___ = true;
-                $(that.element_message).addClass('hidden');
-            }
-        };
+            // REQUIRED! This is where you enter your pie data; it needs to be an array of objects
+            // of this form: { label: "label", value: 1.5, color: "#000000" } - color is optional
+            content: content
+        },
+        labels: {
+            outer: {
+                // label, value, percentage, label-value1, label-value2, label-percentage1, label-percentage2
+                format: NETDATA.dataAttribute(state.element, 'd3pie-labels-outer-format', "label-value1"),
+                hideWhenLessThanPercentage: NETDATA.dataAttribute(state.element, 'd3pie-labels-outer-hidewhenlessthanpercentage', null),
+                pieDistance: NETDATA.dataAttribute(state.element, 'd3pie-labels-outer-piedistance', 15)
+            },
+            inner: {
+                // label, value, percentage, label-value1, label-value2, label-percentage1, label-percentage2
+                format: NETDATA.dataAttribute(state.element, 'd3pie-labels-inner-format', "percentage"),
+                hideWhenLessThanPercentage: NETDATA.dataAttribute(state.element, 'd3pie-labels-inner-hidewhenlessthanpercentage', 2)
+            },
+            mainLabel: {
+                color: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-color', NETDATA.themes.current.d3pie.mainlabel), // or 'segment' for dynamic color
+                font: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-font', "arial"),
+                fontSize: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-fontsize', 10),
+                fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-fontweight', "normal")
+            },
+            percentage: {
+                color: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-color', NETDATA.themes.current.d3pie.percentage),
+                font: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-font', "arial"),
+                fontSize: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-fontsize', 10),
+                fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-fontweight', "bold"),
+                decimalPlaces: 0
+            },
+            value: {
+                color: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-color', NETDATA.themes.current.d3pie.value),
+                font: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-font', "arial"),
+                fontSize: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-fontsize', 10),
+                fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-fontweight', "bold")
+            },
+            lines: {
+                enabled: NETDATA.dataAttributeBoolean(state.element, 'd3pie-labels-lines-enabled', true),
+                style: NETDATA.dataAttribute(state.element, 'd3pie-labels-lines-style', "curved"),
+                color: NETDATA.dataAttribute(state.element, 'd3pie-labels-lines-color', "segment") // "segment" or a hex color
+            },
+            truncation: {
+                enabled: NETDATA.dataAttributeBoolean(state.element, 'd3pie-labels-truncation-enabled', false),
+                truncateLength: NETDATA.dataAttribute(state.element, 'd3pie-labels-truncation-truncatelength', 30)
+            },
+            formatter: function (context) {
+                // console.log(context);
+                if (context.part === 'value') {
+                    return state.legendFormatValue(context.value);
+                }
+                if (context.part === 'percentage') {
+                    return context.label + '%';
+                }
 
-        var showRendering = function() {
-            var icon;
-            if(that.chart !== null) {
-                if(that.chart.chart_type === 'line')
-                    icon = NETDATA.icons.lineChart;
-                else
-                    icon = NETDATA.icons.areaChart;
+                return context.label;
             }
-            else
-                icon = NETDATA.icons.noChart;
-
-            showMessageIcon(icon + ' netdata' + invisibleSearchableText());
-        };
-
-        var showLoading = function() {
-            if(that.chart_created === false) {
-                showMessageIcon(NETDATA.icons.loading + ' netdata');
-                return true;
+        },
+        effects: {
+            load: {
+                effect: "none", // none / default
+                speed: 0 // commented in the d3pie code to speed it up
+            },
+            pullOutSegmentOnClick: {
+                effect: "bounce", // none / linear / bounce / elastic / back
+                speed: 400,
+                size: 5
+            },
+            highlightSegmentOnMouseover: true,
+            highlightLuminosity: -0.2
+        },
+        tooltips: {
+            enabled: false,
+            type: "placeholder", // caption|placeholder
+            string: "",
+            placeholderParser: null, // function
+            styles: {
+                fadeInSpeed: 250,
+                backgroundColor: NETDATA.themes.current.d3pie.tooltip_bg,
+                backgroundOpacity: 0.5,
+                color: NETDATA.themes.current.d3pie.tooltip_fg,
+                borderRadius: 2,
+                font: "arial",
+                fontSize: 12,
+                padding: 4
             }
-            return false;
-        };
+        },
+        misc: {
+            colors: {
+                background: 'transparent', // transparent or color #
+                // segments: state.chartColors(),
+                segmentStroke: NETDATA.dataAttribute(state.element, 'd3pie-misc-colors-segmentstroke', NETDATA.themes.current.d3pie.segment_stroke)
+            },
+            gradient: {
+                enabled: NETDATA.dataAttributeBoolean(state.element, 'd3pie-misc-gradient-enabled', false),
+                percentage: NETDATA.dataAttribute(state.element, 'd3pie-misc-colors-percentage', 95),
+                color: NETDATA.dataAttribute(state.element, 'd3pie-misc-gradient-color', NETDATA.themes.current.d3pie.gradient_color)
+            },
+            canvasPadding: {
+                top: 5,
+                right: 5,
+                bottom: 5,
+                left: 5
+            },
+            pieCenterOffset: {
+                x: 0,
+                y: 0
+            },
+            cssPrefix: NETDATA.dataAttribute(state.element, 'd3pie-cssprefix', null)
+        },
+        callbacks: {
+            onload: null,
+            onMouseoverSegment: null,
+            onMouseoutSegment: null,
+            onClickSegment: null
+        }
+    };
 
-        var isHidden = function() {
-            return (typeof that.tmp.___chartIsHidden___ !== 'undefined');
-        };
+    state.d3pie_instance = new d3pie(state.element_chart, state.d3pie_options);
+    return true;
+};
 
-        // hide the chart, when it is not visible - called from isVisible()
-        this.hideChart = function() {
-            // hide it, if it is not already hidden
-            if(isHidden() === true) return;
-
-            if(this.chart_created === true) {
-                if(NETDATA.options.current.show_help === true) {
-                    if(this.element_legend_childs.toolbox !== null) {
-                        if(this.debug === true)
-                            this.log('hideChart(): hidding legend popovers');
-
-                        $(this.element_legend_childs.toolbox_left).popover('hide');
-                        $(this.element_legend_childs.toolbox_reset).popover('hide');
-                        $(this.element_legend_childs.toolbox_right).popover('hide');
-                        $(this.element_legend_childs.toolbox_zoomin).popover('hide');
-                        $(this.element_legend_childs.toolbox_zoomout).popover('hide');
-                    }
+// ----------------------------------------------------------------------------------------------------------------
+// D3
 
-                    if(this.element_legend_childs.resize_handler !== null)
-                        $(this.element_legend_childs.resize_handler).popover('hide');
+NETDATA.d3Initialize = function(callback) {
+    if (typeof netdataStopD3 === 'undefined' || !netdataStopD3) {
+        $.ajax({
+            url: NETDATA.d3_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: { withCredentials: true } // required for the cookie
+        })
+        .done(function() {
+            NETDATA.registerChartLibrary('d3', NETDATA.d3_js);
+        })
+        .fail(function() {
+            NETDATA.chartLibraries.d3.enabled = false;
+            NETDATA.error(100, NETDATA.d3_js);
+        })
+        .always(function() {
+            if (typeof callback === "function")
+                return callback();
+        });
+    } else {
+        NETDATA.chartLibraries.d3.enabled = false;
+        if (typeof callback === "function")
+            return callback();
+    }
+};
 
-                    if(this.element_legend_childs.content !== null)
-                        $(this.element_legend_childs.content).popover('hide');
-                }
+NETDATA.d3ChartUpdate = function(state, data) {
+    void(state);
+    void(data);
 
-                if(NETDATA.options.current.destroy_on_hide === true) {
-                    if(this.debug === true)
-                        this.log('hideChart(): initializing chart');
+    return false;
+};
 
-                    // we should destroy it
-                    init('force');
-                }
-                else {
-                    if(this.debug === true)
-                        this.log('hideChart(): hiding chart');
+NETDATA.d3ChartCreate = function(state, data) {
+    void(state);
+    void(data);
 
-                    showRendering();
-                    this.element_chart.style.display = 'none';
-                    this.element.style.willChange = 'auto';
-                    if(this.element_legend !== null) this.element_legend.style.display = 'none';
-                    if(this.element_legend_childs.toolbox !== null) this.element_legend_childs.toolbox.style.display = 'none';
-                    if(this.element_legend_childs.resize_handler !== null) this.element_legend_childs.resize_handler.style.display = 'none';
+    return false;
+};
 
-                    this.tm.last_hidden = Date.now();
+// peity
 
-                    // de-allocate data
-                    // This works, but I not sure there are no corner cases somewhere
-                    // so it is commented - if the user has memory issues he can
-                    // set Destroy on Hide for all charts
-                    // this.data = null;
+NETDATA.peityInitialize = function (callback) {
+    if (typeof netdataNoPeitys === 'undefined' || !netdataNoPeitys) {
+        $.ajax({
+            url: NETDATA.peity_js,
+            cache: true,
+            dataType: "script",
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function () {
+                NETDATA.registerChartLibrary('peity', NETDATA.peity_js);
+            })
+            .fail(function () {
+                NETDATA.chartLibraries.peity.enabled = false;
+                NETDATA.error(100, NETDATA.peity_js);
+            })
+            .always(function () {
+                if (typeof callback === "function") {
+                    return callback();
                 }
-            }
-
-            this.tmp.___chartIsHidden___ = true;
-        };
+            });
+    } else {
+        NETDATA.chartLibraries.peity.enabled = false;
+        if (typeof callback === "function") {
+            return callback();
+        }
+    }
+};
 
-        // unhide the chart, when it is visible - called from isVisible()
-        this.unhideChart = function() {
-            if(isHidden() === false) return;
+NETDATA.peityChartUpdate = function (state, data) {
+    state.peity_instance.innerHTML = data.result;
 
-            this.tmp.___chartIsHidden___ = undefined;
-            this.updates_since_last_unhide = 0;
+    if (state.peity_options.stroke !== state.chartCustomColors()[0]) {
+        state.peity_options.stroke = state.chartCustomColors()[0];
+        if (state.chart.chart_type === 'line') {
+            state.peity_options.fill = NETDATA.themes.current.background;
+        } else {
+            state.peity_options.fill = NETDATA.colorLuminance(state.chartCustomColors()[0], NETDATA.chartDefaults.fill_luminance);
+        }
+    }
 
-            if(this.chart_created === false) {
-                if(this.debug === true)
-                    this.log('unhideChart(): initializing chart');
+    $(state.peity_instance).peity('line', state.peity_options);
+    return true;
+};
 
-                // we need to re-initialize it, to show our background
-                // logo in bootstrap tabs, until the chart loads
-                init('force');
-            }
-            else {
-                if(this.debug === true)
-                    this.log('unhideChart(): unhiding chart');
+NETDATA.peityChartCreate = function (state, data) {
+    state.peity_instance = document.createElement('div');
+    state.element_chart.appendChild(state.peity_instance);
 
-                this.element.style.willChange = 'transform';
-                this.tm.last_unhidden = Date.now();
-                this.element_chart.style.display = '';
-                if(this.element_legend !== null) this.element_legend.style.display = '';
-                if(this.element_legend_childs.toolbox !== null) this.element_legend_childs.toolbox.style.display = '';
-                if(this.element_legend_childs.resize_handler !== null) this.element_legend_childs.resize_handler.style.display = '';
-                resizeChart();
-                hideMessage();
-            }
+    state.peity_options = {
+        stroke: NETDATA.themes.current.foreground,
+        strokeWidth: NETDATA.dataAttribute(state.element, 'peity-strokewidth', 1),
+        width: state.chartWidth(),
+        height: state.chartHeight(),
+        fill: NETDATA.themes.current.foreground
+    };
 
-            if(this.__redraw_on_unhide === true) {
+    NETDATA.peityChartUpdate(state, data);
+    return true;
+};
 
-                if(this.debug === true)
-                    this.log("redrawing chart on unhide");
+// Charts Libraries Registration
 
-                this.__redraw_on_unhide = undefined;
-                this.redrawChart();
+NETDATA.chartLibraries = {
+    "dygraph": {
+        initialize: NETDATA.dygraphInitialize,
+        create: NETDATA.dygraphChartCreate,
+        update: NETDATA.dygraphChartUpdate,
+        resize: function (state) {
+            if (typeof state.tmp.dygraph_instance !== 'undefined' && typeof state.tmp.dygraph_instance.resize === 'function') {
+                state.tmp.dygraph_instance.resize();
             }
-        };
-
-        var canBeRendered = function(uncached_visibility) {
-            if(that.debug === true)
-                that.log('canBeRendered() called');
-
-            if(NETDATA.options.current.update_only_visible === false)
-                return true;
-
-            var ret = (
-                (
-                    NETDATA.options.page_is_visible === true ||
-                    NETDATA.options.current.stop_updates_when_focus_is_lost === false ||
-                    that.updates_since_last_unhide === 0
-                )
-                && isHidden() === false && that.isVisible(uncached_visibility) === true
-            );
-
-            if(that.debug === true)
-                that.log('canBeRendered(): ' + ret);
-
-            return ret;
-        };
-
-        // https://github.com/petkaantonov/bluebird/wiki/Optimization-killers
-        var callChartLibraryUpdateSafely = function(data) {
-            var status;
-
-            // we should not do this here
-            // if we prevent rendering the chart then:
-            // 1. globalSelectionSync will be wrong
-            // 2. globalPanAndZoom will be wrong
-            //if(canBeRendered(true) === false)
-            //    return false;
-
-            if(NETDATA.options.fake_chart_rendering === true)
-                return true;
-
-            that.updates_counter++;
-            that.updates_since_last_unhide++;
-            that.updates_since_last_creation++;
-
-            if(NETDATA.options.debug.chart_errors === true)
-                status = that.library.update(that, data);
-            else {
-                try {
-                    status = that.library.update(that, data);
-                }
-                catch(err) {
-                    status = false;
-                }
+        },
+        setSelection: NETDATA.dygraphSetSelection,
+        clearSelection: NETDATA.dygraphClearSelection,
+        toolboxPanAndZoom: NETDATA.dygraphToolboxPanAndZoom,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
+        format: function (state) {
+            void(state);
+            return 'json';
+        },
+        options: function (state) {
+            return 'ms' + '%7C' + 'flip' + (this.isLogScale(state) ? ('%7C' + 'abs') : '').toString();
+        },
+        legend: function (state) {
+            return (this.isSparkline(state) === false && NETDATA.dataAttributeBoolean(state.element, 'legend', true) === true) ? 'right-side' : null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return true;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
+            return true;
+        },
+        pixels_per_point: function (state) {
+            return (this.isSparkline(state) === false) ? 3 : 2;
+        },
+        isSparkline: function (state) {
+            if (typeof state.tmp.dygraph_sparkline === 'undefined') {
+                state.tmp.dygraph_sparkline = (this.theme(state) === 'sparkline');
             }
-
-            if(status === false) {
-                error('chart failed to be updated as ' + that.library_name);
-                return false;
+            return state.tmp.dygraph_sparkline;
+        },
+        isLogScale: function (state) {
+            if (typeof state.tmp.dygraph_logscale === 'undefined') {
+                state.tmp.dygraph_logscale = (this.theme(state) === 'logscale');
             }
-
+            return state.tmp.dygraph_logscale;
+        },
+        theme: function (state) {
+            if (typeof state.tmp.dygraph_theme === 'undefined') {
+                state.tmp.dygraph_theme = NETDATA.dataAttribute(state.element, 'dygraph-theme', 'default');
+            }
+            return state.tmp.dygraph_theme;
+        },
+        container_class: function (state) {
+            if (this.legend(state) !== null) {
+                return 'netdata-container-with-legend';
+            }
+            return 'netdata-container';
+        }
+    },
+    "sparkline": {
+        initialize: NETDATA.sparklineInitialize,
+        create: NETDATA.sparklineChartCreate,
+        update: NETDATA.sparklineChartUpdate,
+        resize: null,
+        setSelection: undefined, // function(state, t) { void(state); return true; },
+        clearSelection: undefined, // function(state) { void(state); return true; },
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
+        format: function (state) {
+            void(state);
+            return 'array';
+        },
+        options: function (state) {
+            void(state);
+            return 'flip' + '%7C' + 'abs';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
+            return false;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 3;
+        },
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container';
+        }
+    },
+    "peity": {
+        initialize: NETDATA.peityInitialize,
+        create: NETDATA.peityChartCreate,
+        update: NETDATA.peityChartUpdate,
+        resize: null,
+        setSelection: undefined, // function(state, t) { void(state); return true; },
+        clearSelection: undefined, // function(state) { void(state); return true; },
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
+        format: function (state) {
+            void(state);
+            return 'ssvcomma';
+        },
+        options: function (state) {
+            void(state);
+            return 'null2zero' + '%7C' + 'flip' + '%7C' + 'abs';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
+            return false;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 3;
+        },
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container';
+        }
+    },
+    // "morris": {
+    //     initialize: NETDATA.morrisInitialize,
+    //     create: NETDATA.morrisChartCreate,
+    //     update: NETDATA.morrisChartUpdate,
+    //     resize: null,
+    //     setSelection: undefined, // function(state, t) { void(state); return true; },
+    //     clearSelection: undefined, // function(state) { void(state); return true; },
+    //     toolboxPanAndZoom: null,
+    //     initialized: false,
+    //     enabled: true,
+    //     xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
+    //     format: function(state) { void(state); return 'json'; },
+    //     options: function(state) { void(state); return 'objectrows' + '%7C' + 'ms'; },
+    //     legend: function(state) { void(state); return null; },
+    //     autoresize: function(state) { void(state); return false; },
+    //     max_updates_to_recreate: function(state) { void(state); return 50; },
+    //     track_colors: function(state) { void(state); return false; },
+    //     pixels_per_point: function(state) { void(state); return 15; },
+    //     container_class: function(state) { void(state); return 'netdata-container'; }
+    // },
+    "google": {
+        initialize: NETDATA.googleInitialize,
+        create: NETDATA.googleChartCreate,
+        update: NETDATA.googleChartUpdate,
+        resize: null,
+        setSelection: undefined, //function(state, t) { void(state); return true; },
+        clearSelection: undefined, //function(state) { void(state); return true; },
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result.rows$'),
+        format: function (state) {
+            void(state);
+            return 'datatable';
+        },
+        options: function (state) {
+            void(state);
+            return '';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 300;
+        },
+        track_colors: function (state) {
+            void(state);
+            return false;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 4;
+        },
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container';
+        }
+    },
+    // "raphael": {
+    //     initialize: NETDATA.raphaelInitialize,
+    //     create: NETDATA.raphaelChartCreate,
+    //     update: NETDATA.raphaelChartUpdate,
+    //     resize: null,
+    //     setSelection: undefined, // function(state, t) { void(state); return true; },
+    //     clearSelection: undefined, // function(state) { void(state); return true; },
+    //     toolboxPanAndZoom: null,
+    //     initialized: false,
+    //     enabled: true,
+    //     xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
+    //     format: function(state) { void(state); return 'json'; },
+    //     options: function(state) { void(state); return ''; },
+    //     legend: function(state) { void(state); return null; },
+    //     autoresize: function(state) { void(state); return false; },
+    //     max_updates_to_recreate: function(state) { void(state); return 5000; },
+    //     track_colors: function(state) { void(state); return false; },
+    //     pixels_per_point: function(state) { void(state); return 3; },
+    //     container_class: function(state) { void(state); return 'netdata-container'; }
+    // },
+    // "c3": {
+    //     initialize: NETDATA.c3Initialize,
+    //     create: NETDATA.c3ChartCreate,
+    //     update: NETDATA.c3ChartUpdate,
+    //     resize: null,
+    //     setSelection: undefined, // function(state, t) { void(state); return true; },
+    //     clearSelection: undefined, // function(state) { void(state); return true; },
+    //     toolboxPanAndZoom: null,
+    //     initialized: false,
+    //     enabled: true,
+    //     xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
+    //     format: function(state) { void(state); return 'csvjsonarray'; },
+    //     options: function(state) { void(state); return 'milliseconds'; },
+    //     legend: function(state) { void(state); return null; },
+    //     autoresize: function(state) { void(state); return false; },
+    //     max_updates_to_recreate: function(state) { void(state); return 5000; },
+    //     track_colors: function(state) { void(state); return false; },
+    //     pixels_per_point: function(state) { void(state); return 15; },
+    //     container_class: function(state) { void(state); return 'netdata-container'; }
+    // },
+    "d3pie": {
+        initialize: NETDATA.d3pieInitialize,
+        create: NETDATA.d3pieChartCreate,
+        update: NETDATA.d3pieChartUpdate,
+        resize: null,
+        setSelection: NETDATA.d3pieSetSelection,
+        clearSelection: NETDATA.d3pieClearSelection,
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
+        format: function (state) {
+            void(state);
+            return 'json';
+        },
+        options: function (state) {
+            void(state);
+            return 'objectrows' + '%7C' + 'ms';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
+            return false;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 15;
+        },
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container';
+        }
+    },
+    "d3": {
+        initialize: NETDATA.d3Initialize,
+        create: NETDATA.d3ChartCreate,
+        update: NETDATA.d3ChartUpdate,
+        resize: null,
+        setSelection: undefined, // function(state, t) { void(state); return true; },
+        clearSelection: undefined, // function(state) { void(state); return true; },
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
+        format: function (state) {
+            void(state);
+            return 'json';
+        },
+        options: function (state) {
+            void(state);
+            return '';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
+            return false;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 3;
+        },
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container';
+        }
+    },
+    "easypiechart": {
+        initialize: NETDATA.easypiechartInitialize,
+        create: NETDATA.easypiechartChartCreate,
+        update: NETDATA.easypiechartChartUpdate,
+        resize: null,
+        setSelection: NETDATA.easypiechartSetSelection,
+        clearSelection: NETDATA.easypiechartClearSelection,
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
+        format: function (state) {
+            void(state);
+            return 'array';
+        },
+        options: function (state) {
+            void(state);
+            return 'absolute';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
             return true;
-        };
-
-        // https://github.com/petkaantonov/bluebird/wiki/Optimization-killers
-        var callChartLibraryCreateSafely = function(data) {
-            var status;
-
-            // we should not do this here
-            // if we prevent rendering the chart then:
-            // 1. globalSelectionSync will be wrong
-            // 2. globalPanAndZoom will be wrong
-            //if(canBeRendered(true) === false)
-            //    return false;
-
-            if(NETDATA.options.fake_chart_rendering === true)
-                return true;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 3;
+        },
+        aspect_ratio: 100,
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container-easypiechart';
+        }
+    },
+    "gauge": {
+        initialize: NETDATA.gaugeInitialize,
+        create: NETDATA.gaugeChartCreate,
+        update: NETDATA.gaugeChartUpdate,
+        resize: null,
+        setSelection: NETDATA.gaugeSetSelection,
+        clearSelection: NETDATA.gaugeClearSelection,
+        toolboxPanAndZoom: null,
+        initialized: false,
+        enabled: true,
+        xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
+        format: function (state) {
+            void(state);
+            return 'array';
+        },
+        options: function (state) {
+            void(state);
+            return 'absolute';
+        },
+        legend: function (state) {
+            void(state);
+            return null;
+        },
+        autoresize: function (state) {
+            void(state);
+            return false;
+        },
+        max_updates_to_recreate: function (state) {
+            void(state);
+            return 5000;
+        },
+        track_colors: function (state) {
+            void(state);
+            return true;
+        },
+        pixels_per_point: function (state) {
+            void(state);
+            return 3;
+        },
+        aspect_ratio: 60,
+        container_class: function (state) {
+            void(state);
+            return 'netdata-container-gauge';
+        }
+    }
+};
 
-            that.updates_counter++;
-            that.updates_since_last_unhide++;
-            that.updates_since_last_creation++;
+NETDATA.registerChartLibrary = function (library, url) {
+    if (NETDATA.options.debug.libraries) {
+        console.log("registering chart library: " + library);
+    }
 
-            if(NETDATA.options.debug.chart_errors === true)
-                status = that.library.create(that, data);
-            else {
-                try {
-                    status = that.library.create(that, data);
-                }
-                catch(err) {
-                    status = false;
-                }
-            }
+    NETDATA.chartLibraries[library].url = url;
+    NETDATA.chartLibraries[library].initialized = true;
+    NETDATA.chartLibraries[library].enabled = true;
+};
+// ----------------------------------------------------------------------------------------------------------------
+// Detect the netdata server
+
+// http://stackoverflow.com/questions/984510/what-is-my-script-src-url
+// http://stackoverflow.com/questions/6941533/get-protocol-domain-and-port-from-url
+NETDATA._scriptSource = function () {
+    let script = null;
+
+    if (typeof document.currentScript !== 'undefined') {
+        script = document.currentScript;
+    } else {
+        const all_scripts = document.getElementsByTagName('script');
+        script = all_scripts[all_scripts.length - 1];
+    }
 
-            if(status === false) {
-                error('chart failed to be created as ' + that.library_name);
-                return false;
-            }
+    if (typeof script.getAttribute.length !== 'undefined') {
+        script = script.src;
+    } else {
+        script = script.getAttribute('src', -1);
+    }
 
-            that.chart_created = true;
-            that.updates_since_last_creation = 0;
-            return true;
-        };
+    return script;
+};
+
+if (typeof netdataServer !== 'undefined') {
+    NETDATA.serverDefault = netdataServer;
+} else {
+    let s = NETDATA._scriptSource();
+    if (s) {
+        NETDATA.serverDefault = s.replace(/\/dashboard.js(\?.*)?$/g, "");
+    } else {
+        console.log('WARNING: Cannot detect the URL of the netdata server.');
+        NETDATA.serverDefault = null;
+    }
+}
+
+if (NETDATA.serverDefault === null) {
+    NETDATA.serverDefault = '';
+} else if (NETDATA.serverDefault.slice(-1) !== '/') {
+    NETDATA.serverDefault += '/';
+}
+
+if (typeof netdataServerStatic !== 'undefined' && netdataServerStatic !== null && netdataServerStatic !== '') {
+    NETDATA.serverStatic = netdataServerStatic;
+    if (NETDATA.serverStatic.slice(-1) !== '/') {
+        NETDATA.serverStatic += '/';
+    }
+} else {
+    NETDATA.serverStatic = NETDATA.serverDefault;
+}
+
+// default URLs for all the external files we need
+// make them RELATIVE so that the whole thing can also be
+// installed under a web server
+NETDATA.jQuery = NETDATA.serverStatic + 'lib/jquery-2.2.4.min.js';
+NETDATA.peity_js = NETDATA.serverStatic + 'lib/jquery.peity-3.2.0.min.js';
+NETDATA.sparkline_js = NETDATA.serverStatic + 'lib/jquery.sparkline-2.1.2.min.js';
+NETDATA.easypiechart_js = NETDATA.serverStatic + 'lib/jquery.easypiechart-97b5824.min.js';
+NETDATA.gauge_js = NETDATA.serverStatic + 'lib/gauge-1.3.2.min.js';
+NETDATA.dygraph_js = NETDATA.serverStatic + 'lib/dygraph-c91c859.min.js';
+NETDATA.dygraph_smooth_js = NETDATA.serverStatic + 'lib/dygraph-smooth-plotter-c91c859.js';
+// NETDATA.raphael_js          = NETDATA.serverStatic + 'lib/raphael-2.2.4-min.js';
+// NETDATA.c3_js               = NETDATA.serverStatic + 'lib/c3-0.4.18.min.js';
+// NETDATA.c3_css              = NETDATA.serverStatic + 'css/c3-0.4.18.min.css';
+NETDATA.d3pie_js = NETDATA.serverStatic + 'lib/d3pie-0.2.1-netdata-3.js';
+NETDATA.d3_js = NETDATA.serverStatic + 'lib/d3-4.12.2.min.js';
+// NETDATA.morris_js           = NETDATA.serverStatic + 'lib/morris-0.5.1.min.js';
+// NETDATA.morris_css          = NETDATA.serverStatic + 'css/morris-0.5.1.css';
+NETDATA.google_js = 'https://www.google.com/jsapi';
+
+NETDATA.themes = {
+    white: {
+        bootstrap_css: NETDATA.serverStatic + 'css/bootstrap-3.3.7.css',
+        dashboard_css: NETDATA.serverStatic + 'dashboard.css?v20180210-1',
+        background: '#FFFFFF',
+        foreground: '#000000',
+        grid: '#F0F0F0',
+        axis: '#F0F0F0',
+        highlight: '#F5F5F5',
+        colors: ['#3366CC', '#DC3912', '#109618', '#FF9900', '#990099', '#DD4477',
+            '#3B3EAC', '#66AA00', '#0099C6', '#B82E2E', '#AAAA11', '#5574A6',
+            '#994499', '#22AA99', '#6633CC', '#E67300', '#316395', '#8B0707',
+            '#329262', '#3B3EAC'],
+        easypiechart_track: '#f0f0f0',
+        easypiechart_scale: '#dfe0e0',
+        gauge_pointer: '#C0C0C0',
+        gauge_stroke: '#F0F0F0',
+        gauge_gradient: false,
+        d3pie: {
+            title: '#333333',
+            subtitle: '#666666',
+            footer: '#888888',
+            other: '#aaaaaa',
+            mainlabel: '#333333',
+            percentage: '#dddddd',
+            value: '#aaaa22',
+            tooltip_bg: '#000000',
+            tooltip_fg: '#efefef',
+            segment_stroke: "#ffffff",
+            gradient_color: '#000000'
+        }
+    },
+    slate: {
+        bootstrap_css: NETDATA.serverStatic + 'css/bootstrap-slate-flat-3.3.7.css?v20161229-1',
+        dashboard_css: NETDATA.serverStatic + 'dashboard.slate.css?v20180210-1',
+        background: '#272b30',
+        foreground: '#C8C8C8',
+        grid: '#283236',
+        axis: '#283236',
+        highlight: '#383838',
+        /*          colors: [   '#55bb33', '#ff2222',   '#0099C6', '#faa11b',   '#adbce0', '#DDDD00',
+                            '#4178ba', '#f58122',   '#a5cc39', '#f58667',   '#f5ef89', '#cf93c0',
+                            '#a5d18a', '#b8539d',   '#3954a3', '#c8a9cf',   '#c7de8a', '#fad20a',
+                            '#a6a479', '#a66da8' ],
+        */
+        colors: ['#66AA00', '#FE3912', '#3366CC', '#D66300', '#0099C6', '#DDDD00',
+            '#5054e6', '#EE9911', '#BB44CC', '#e45757', '#ef0aef', '#CC7700',
+            '#22AA99', '#109618', '#905bfd', '#f54882', '#4381bf', '#ff3737',
+            '#329262', '#3B3EFF'],
+        easypiechart_track: '#373b40',
+        easypiechart_scale: '#373b40',
+        gauge_pointer: '#474b50',
+        gauge_stroke: '#373b40',
+        gauge_gradient: false,
+        d3pie: {
+            title: '#C8C8C8',
+            subtitle: '#283236',
+            footer: '#283236',
+            other: '#283236',
+            mainlabel: '#C8C8C8',
+            percentage: '#dddddd',
+            value: '#cccc44',
+            tooltip_bg: '#272b30',
+            tooltip_fg: '#C8C8C8',
+            segment_stroke: "#283236",
+            gradient_color: '#000000'
+        }
+    }
+};
 
-        // ----------------------------------------------------------------------------------------------------------------
-        // Chart Resize
+if (typeof netdataTheme !== 'undefined' && typeof NETDATA.themes[netdataTheme] !== 'undefined') {
+    NETDATA.themes.current = NETDATA.themes[netdataTheme];
+} else {
+    NETDATA.themes.current = NETDATA.themes.white;
+}
 
-        // resizeChart() - private
-        // to be called just before the chart library to make sure that
-        // a properly sized dom is available
-        var resizeChart = function() {
-            if(that.tm.last_resized < NETDATA.options.last_page_resize) {
-                if(that.chart_created === false) return;
+NETDATA.colors = NETDATA.themes.current.colors;
 
-                if(that.needsRecreation()) {
-                    if(that.debug === true)
-                        that.log('resizeChart(): initializing chart');
+// these are the colors Google Charts are using
+// we have them here to attempt emulate their look and feel on the other chart libraries
+// http://there4.io/2012/05/02/google-chart-color-list/
+//NETDATA.colors        = [ '#3366CC', '#DC3912', '#FF9900', '#109618', '#990099', '#3B3EAC', '#0099C6',
+//                      '#DD4477', '#66AA00', '#B82E2E', '#316395', '#994499', '#22AA99', '#AAAA11',
+//                      '#6633CC', '#E67300', '#8B0707', '#329262', '#5574A6', '#3B3EAC' ];
 
-                    init('force');
-                }
-                else if(typeof that.library.resize === 'function') {
-                    if(that.debug === true)
-                        that.log('resizeChart(): resizing chart');
+// an alternative set
+// http://www.mulinblog.com/a-color-palette-optimized-for-data-visualization/
+//                         (blue)     (red)      (orange)   (green)    (pink)     (brown)    (purple)   (yellow)   (gray)
+//NETDATA.colors        = [ '#5DA5DA', '#F15854', '#FAA43A', '#60BD68', '#F17CB0', '#B2912F', '#B276B2', '#DECF3F', '#4D4D4D' ];
 
-                    that.library.resize(that);
+// ----------------------------------------------------------------------------------------------------------------
 
-                    if(that.element_legend_childs.perfect_scroller !== null)
-                        Ps.update(that.element_legend_childs.perfect_scroller);
+NETDATA.timeout = {
+    // by default, these are just wrappers to setTimeout() / clearTimeout()
 
-                    maxMessageFontSize();
-                }
+    step: function (callback) {
+        return window.setTimeout(callback, 1000 / 60);
+    },
 
-                that.tm.last_resized = Date.now();
-            }
-        };
+    set: function (callback, delay) {
+        return window.setTimeout(callback, delay);
+    },
 
-        // this is the actual chart resize algorithm
-        // it will:
-        // - resize the entire container
-        // - update the internal states
-        // - resize the chart as the div changes height
-        // - update the scrollbar of the legend
-        var resizeChartToHeight = function(h) {
-            // console.log(h);
-            that.element.style.height = h;
-
-            if(that.settings_id !== null)
-                NETDATA.localStorageSet('chart_heights.' + that.settings_id, h);
-
-            var now = Date.now();
-            NETDATA.options.last_page_scroll = now;
-            NETDATA.options.auto_refresher_stop_until = now + NETDATA.options.current.stop_updates_while_resizing;
-
-            // force a resize
-            that.tm.last_resized = 0;
-            resizeChart();
-        };
+    clear: function (id) {
+        return window.clearTimeout(id);
+    },
 
-        this.resizeForPrint = function() {
-            if(typeof this.element_legend_childs !== 'undefined' && this.element_legend_childs.perfect_scroller !== null) {
-                var current = this.element.clientHeight;
-                var optimal = current
-                    + this.element_legend_childs.perfect_scroller.scrollHeight
-                    - this.element_legend_childs.perfect_scroller.clientHeight;
+    init: function () {
+        let custom = true;
 
-                if(optimal > current) {
-                    // this.log('resized');
-                    this.element.style.height = optimal + 'px';
-                    this.library.resize(this);
-                }
-            }
-        };
+        if (window.requestAnimationFrame) {
+            this.step = function (callback) {
+                return window.requestAnimationFrame(callback);
+            };
 
-        this.resizeHandler = function(e) {
-            e.preventDefault();
+            this.clear = function (handle) {
+                return window.cancelAnimationFrame(handle.value);
+            };
+        } else if (window.webkitRequestAnimationFrame) {
+            this.step = function (callback) {
+                return window.webkitRequestAnimationFrame(callback);
+            };
 
-            if(typeof this.event_resize === 'undefined'
-                || this.event_resize.chart_original_w === 'undefined'
-                || this.event_resize.chart_original_h === 'undefined')
-                this.event_resize = {
-                    chart_original_w: this.element.clientWidth,
-                    chart_original_h: this.element.clientHeight,
-                    last: 0
+            if (window.webkitCancelAnimationFrame) {
+                this.clear = function (handle) {
+                    return window.webkitCancelAnimationFrame(handle.value);
+                };
+            } else if (window.webkitCancelRequestAnimationFrame) {
+                this.clear = function (handle) {
+                    return window.webkitCancelRequestAnimationFrame(handle.value);
                 };
-
-            if(e.type === 'touchstart') {
-                this.event_resize.mouse_start_x = e.touches.item(0).pageX;
-                this.event_resize.mouse_start_y = e.touches.item(0).pageY;
-            }
-            else {
-                this.event_resize.mouse_start_x = e.clientX;
-                this.event_resize.mouse_start_y = e.clientY;
             }
+        } else if (window.mozRequestAnimationFrame) {
+            this.step = function (callback) {
+                return window.mozRequestAnimationFrame(callback);
+            };
 
-            this.event_resize.chart_start_w = this.element.clientWidth;
-            this.event_resize.chart_start_h = this.element.clientHeight;
-            this.event_resize.chart_last_w = this.element.clientWidth;
-            this.event_resize.chart_last_h = this.element.clientHeight;
-
-            var now = Date.now();
-            if(now - this.event_resize.last <= NETDATA.options.current.double_click_speed && this.element_legend_childs.perfect_scroller !== null) {
-                // double click / double tap event
-
-                // console.dir(this.element_legend_childs.content);
-                // console.dir(this.element_legend_childs.perfect_scroller);
+            this.clear = function (handle) {
+                return window.mozCancelRequestAnimationFrame(handle.value);
+            };
+        } else if (window.oRequestAnimationFrame) {
+            this.step = function (callback) {
+                return window.oRequestAnimationFrame(callback);
+            };
 
-                // the optimal height of the chart
-                // showing the entire legend
-                var optimal = this.event_resize.chart_last_h
-                        + this.element_legend_childs.perfect_scroller.scrollHeight
-                        - this.element_legend_childs.perfect_scroller.clientHeight;
+            this.clear = function (handle) {
+                return window.oCancelRequestAnimationFrame(handle.value);
+            };
+        } else if (window.msRequestAnimationFrame) {
+            this.step = function (callback) {
+                return window.msRequestAnimationFrame(callback);
+            };
 
-                // if we are not optimal, be optimal
-                if(this.event_resize.chart_last_h !== optimal) {
-                    // this.log('resize to optimal, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString());
-                    resizeChartToHeight(optimal.toString() + 'px');
-                }
+            this.clear = function (handle) {
+                return window.msCancelRequestAnimationFrame(handle.value);
+            };
+        } else {
+            custom = false;
+        }
 
-                // else if the current height is not the original/saved height
-                // reset to the original/saved height
-                else if(this.event_resize.chart_last_h !== this.event_resize.chart_original_h) {
-                    // this.log('resize to original, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString());
-                    resizeChartToHeight(this.event_resize.chart_original_h.toString() + 'px');
-                }
+        if (custom) {
+            // we have installed custom .step() / .clear() functions
+            // overwrite the .set() too
 
-                // else if the current height is not the internal default height
-                // reset to the internal default height
-                else if((this.event_resize.chart_last_h.toString() + 'px') !== this.height_original) {
-                    // this.log('resize to internal default, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString());
-                    resizeChartToHeight(this.height_original.toString());
-                }
+            this.set = function (callback, delay) {
+                let that = this;
 
-                // else if the current height is not the firstchild's clientheight
-                // resize to it
-                else if(typeof this.element_legend_childs.perfect_scroller.firstChild !== 'undefined') {
-                    var parent_rect = this.element.getBoundingClientRect();
-                    var content_rect = this.element_legend_childs.perfect_scroller.firstElementChild.getBoundingClientRect();
-                    var wanted = content_rect.top - parent_rect.top + this.element_legend_childs.perfect_scroller.firstChild.clientHeight + 18; // 15 = toolbox + 3 space
+                let start = Date.now(),
+                    handle = new Object();
 
-                    // console.log(parent_rect);
-                    // console.log(content_rect);
-                    // console.log(wanted);
+                function loop() {
+                    let current = Date.now(),
+                        delta = current - start;
 
-                    // this.log('resize to firstChild, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString() + 'px, firstChild = ' + wanted.toString() + 'px' );
-                    if(this.event_resize.chart_last_h !== wanted)
-                        resizeChartToHeight(wanted.toString() + 'px');
+                    if (delta >= delay) {
+                        callback.call();
+                    } else {
+                        handle.value = that.step(loop);
+                    }
                 }
-            }
-            else {
-                this.event_resize.last = now;
 
-                // process movement event
-                document.onmousemove =
-                document.ontouchmove =
-                this.element_legend_childs.resize_handler.onmousemove =
-                this.element_legend_childs.resize_handler.ontouchmove =
-                    function(e) {
-                        var y = null;
-
-                        switch(e.type) {
-                            case 'mousemove': y = e.clientY; break;
-                            case 'touchmove': y = e.touches.item(e.touches - 1).pageY; break;
-                        }
-
-                        if(y !== null) {
-                            var newH = that.event_resize.chart_start_h + y - that.event_resize.mouse_start_y;
+                handle.value = that.step(loop);
+                return handle;
+            };
+        }
+    }
+};
 
-                            if(newH >= 70 && newH !== that.event_resize.chart_last_h) {
-                                resizeChartToHeight(newH.toString() + 'px');
-                                that.event_resize.chart_last_h = newH;
-                            }
-                        }
-                    };
+NETDATA.timeout.init();
 
-                // process end event
-                document.onmouseup =
-                document.ontouchend =
-                this.element_legend_childs.resize_handler.onmouseup =
-                this.element_legend_childs.resize_handler.ontouchend =
-                    function(e) {
-                        void(e);
-
-                        // remove all the hooks
-                        document.onmouseup =
-                        document.onmousemove =
-                        document.ontouchmove =
-                        document.ontouchend =
-                        that.element_legend_childs.resize_handler.onmousemove =
-                        that.element_legend_childs.resize_handler.ontouchmove =
-                        that.element_legend_childs.resize_handler.onmouseout =
-                        that.element_legend_childs.resize_handler.onmouseup =
-                        that.element_legend_childs.resize_handler.ontouchend =
-                            null;
-
-                        // allow auto-refreshes
-                        NETDATA.options.auto_refresher_stop_until = 0;
-                    };
-            }
-        };
+// ----------------------------------------------------------------------------------------------------------------
 
+if (NETDATA.options.debug.main_loop) {
+    console.log('welcome to NETDATA');
+}
 
-        var noDataToShow = function() {
-            showMessageIcon(NETDATA.icons.noData + ' empty');
-            that.legendUpdateDOM();
-            that.tm.last_autorefreshed = Date.now();
-            // that.data_update_every = 30 * 1000;
-            //that.element_chart.style.display = 'none';
-            //if(that.element_legend !== null) that.element_legend.style.display = 'none';
-            //that.tmp.___chartIsHidden___ = true;
-        };
+NETDATA.onresizeCallback = null;
+NETDATA.onresize = function () {
+    NETDATA.options.last_page_resize = Date.now();
+    NETDATA.onscroll();
 
-        // ============================================================================================================
-        // PUBLIC FUNCTIONS
+    if (typeof NETDATA.onresizeCallback === 'function') {
+        NETDATA.onresizeCallback();
+    }
+};
 
-        this.error = function(msg) {
-            error(msg);
-        };
+NETDATA.abort_all_refreshes = function () {
+    let targets = NETDATA.options.targets;
+    let len = targets.length;
 
-        this.setMode = function(m) {
-            if(this.current !== null && this.current.name === m) return;
+    while (len--) {
+        if (targets[len].fetching_data) {
+            if (typeof targets[len].xhr !== 'undefined') {
+                targets[len].xhr.abort();
+                targets[len].running = false;
+                targets[len].fetching_data = false;
+            }
+        }
+    }
+};
 
-            if(m === 'auto')
-                this.current = this.auto;
-            else if(m === 'pan')
-                this.current = this.pan;
-            else if(m === 'zoom')
-                this.current = this.zoom;
-            else
-                this.current = this.auto;
+NETDATA.onscroll_start_delay = function () {
+    NETDATA.options.last_page_scroll = Date.now();
 
-            this.current.force_update_at = 0;
-            this.current.force_before_ms = null;
-            this.current.force_after_ms = null;
+    NETDATA.options.on_scroll_refresher_stop_until =
+        NETDATA.options.last_page_scroll
+        + (NETDATA.options.current.async_on_scroll ? 1000 : 0);
+};
 
-            this.tm.last_mode_switch = Date.now();
-        };
+NETDATA.onscroll_end_delay = function () {
+    NETDATA.options.on_scroll_refresher_stop_until =
+        Date.now()
+        + (NETDATA.options.current.async_on_scroll ? NETDATA.options.current.onscroll_worker_duration_threshold : 0);
+};
 
-        // ----------------------------------------------------------------------------------------------------------------
-        // global selection sync for slaves
+NETDATA.onscroll_updater_timeout_id = undefined;
+NETDATA.onscroll_updater = function () {
+    NETDATA.globalSelectionSync.stop();
 
-        // can the chart participate to the global selection sync as a slave?
-        this.globalSelectionSyncIsEligible = function() {
-            return (this.enabled === true
-                && this.library !== null
-                && typeof this.library.setSelection === 'function'
-                && this.isVisible() === true
-                && this.chart_created === true);
-        };
+    if (NETDATA.options.abort_ajax_on_scroll) {
+        NETDATA.abort_all_refreshes();
+    }
 
-        this.setSelection = function(t) {
-            if(typeof this.library.setSelection === 'function')
-                this.selected = (this.library.setSelection(this, t) === true);
-            else
-                this.selected = true;
+    // when the user scrolls he sees that we have
+    // hidden all the not-visible charts
+    // using this little function we try to switch
+    // the charts back to visible quickly
 
-            if(this.selected === true && this.debug === true)
-                this.log('selection set to ' + t.toString());
+    // if (NETDATA.intersectionObserver.enabled() === false) {
+    if (!NETDATA.intersectionObserver.enabled()) {
+        // if (NETDATA.options.current.parallel_refresher === false) {
+        if (!NETDATA.options.current.parallel_refresher) {
+            let targets = NETDATA.options.targets;
+            let len = targets.length;
 
-            if (this.foreign_element_selection !== null)
-                this.foreign_element_selection.innerText = NETDATA.dateTime.localeDateString(t) + ' ' + NETDATA.dateTime.localeTimeString(t);
+            while (len--) {
+                if (!targets[len].running) {
+                    // if (targets[len].running === false) {
+                    targets[len].isVisible();
+                }
+            }
+        }
+    }
 
-            return this.selected;
-        };
+    NETDATA.onscroll_end_delay();
+};
 
-        this.clearSelection = function() {
-            if(this.selected === true) {
-                if(typeof this.library.clearSelection === 'function')
-                    this.selected = (this.library.clearSelection(this) !== true);
-                else
-                    this.selected = false;
+NETDATA.scrollUp = false;
+NETDATA.scrollY = window.scrollY;
+NETDATA.onscroll = function () {
+    //console.log('onscroll() begin');
 
-                if(this.selected === false && this.debug === true)
-                    this.log('selection cleared');
+    NETDATA.onscroll_start_delay();
+    NETDATA.chartRefresherReschedule();
 
-                if (this.foreign_element_selection !== null)
-                    this.foreign_element_selection.innerText = '';
+    NETDATA.scrollUp = (window.scrollY > NETDATA.scrollY);
+    NETDATA.scrollY = window.scrollY;
 
-                this.legendReset();
-            }
+    if (NETDATA.onscroll_updater_timeout_id) {
+        NETDATA.timeout.clear(NETDATA.onscroll_updater_timeout_id);
+    }
 
-            return this.selected;
-        };
+    NETDATA.onscroll_updater_timeout_id = NETDATA.timeout.set(NETDATA.onscroll_updater, 0);
+    //console.log('onscroll() end');
+};
 
-        // ----------------------------------------------------------------------------------------------------------------
+NETDATA.supportsPassiveEvents = function () {
+    if (NETDATA.options.passive_events === null) {
+        let supportsPassive = false;
+        try {
+            let opts = Object.defineProperty({}, 'passive', {
+                get: function () {
+                    supportsPassive = true;
+                }
+            });
+            window.addEventListener("test", null, opts);
+        } catch (e) {
+            console.log('browser does not support passive events');
+        }
 
-        // find if a timestamp (ms) is shown in the current chart
-        this.timeIsVisible = function(t) {
-            return (t >= this.data_after && t <= this.data_before);
-        };
+        NETDATA.options.passive_events = supportsPassive;
+    }
 
-        this.calculateRowForTime = function(t) {
-            if(this.timeIsVisible(t) === false) return -1;
-            return Math.floor((t - this.data_after) / this.data_update_every);
-        };
+    // console.log('passive ' + NETDATA.options.passive_events);
+    return NETDATA.options.passive_events;
+};
 
-        // ----------------------------------------------------------------------------------------------------------------
+window.addEventListener('resize', NETDATA.onresize, NETDATA.supportsPassiveEvents() ? {passive: true} : false);
+window.addEventListener('scroll', NETDATA.onscroll, NETDATA.supportsPassiveEvents() ? {passive: true} : false);
+// window.onresize = NETDATA.onresize;
+// window.onscroll = NETDATA.onscroll;
 
-        this.pauseChart = function() {
-            if(this.paused === false) {
-                if(this.debug === true)
-                    this.log('pauseChart()');
+// ----------------------------------------------------------------------------------------------------------------
+// commonMin & commonMax
 
-                this.paused = true;
-            }
-        };
+NETDATA.commonMin = {
+    keys: {},
+    latest: {},
 
-        this.unpauseChart = function() {
-            if(this.paused === true) {
-                if(this.debug === true)
-                    this.log('unpauseChart()');
+    globalReset: function () {
+        this.keys = {};
+        this.latest = {};
+    },
 
-                this.paused = false;
-            }
-        };
+    get: function (state) {
+        if (typeof state.tmp.__commonMin === 'undefined') {
+            // get the commonMin setting
+            state.tmp.__commonMin = NETDATA.dataAttribute(state.element, 'common-min', null);
+        }
 
-        this.resetChart = function(dont_clear_master, dont_update) {
-            if(this.debug === true)
-                this.log('resetChart(' + dont_clear_master + ', ' + dont_update + ') called');
+        let min = state.data.min;
+        let name = state.tmp.__commonMin;
 
-            if(typeof dont_clear_master === 'undefined')
-                dont_clear_master = false;
+        if (name === null) {
+            // we don't need commonMin
+            //state.log('no need for commonMin');
+            return min;
+        }
 
-            if(typeof dont_update === 'undefined')
-                dont_update = false;
+        let t = this.keys[name];
+        if (typeof t === 'undefined') {
+            // add our commonMin
+            this.keys[name] = {};
+            t = this.keys[name];
+        }
 
-            if(dont_clear_master !== true && NETDATA.globalPanAndZoom.isMaster(this) === true) {
-                if(this.debug === true)
-                    this.log('resetChart() diverting to clearMaster().');
-                // this will call us back with master === true
-                NETDATA.globalPanAndZoom.clearMaster();
-                return;
+        let uuid = state.uuid;
+        if (typeof t[uuid] !== 'undefined') {
+            if (t[uuid] === min) {
+                //state.log('commonMin ' + state.tmp.__commonMin + ' not changed: ' + this.latest[name]);
+                return this.latest[name];
+            } else if (min < this.latest[name]) {
+                //state.log('commonMin ' + state.tmp.__commonMin + ' increased: ' + min);
+                t[uuid] = min;
+                this.latest[name] = min;
+                return min;
             }
+        }
 
-            this.clearSelection();
-
-            this.tm.pan_and_zoom_seq = 0;
-
-            this.setMode('auto');
-            this.current.force_update_at = 0;
-            this.current.force_before_ms = null;
-            this.current.force_after_ms = null;
-            this.tm.last_autorefreshed = 0;
-            this.paused = false;
-            this.selected = false;
-            this.enabled = true;
-            // this.debug = false;
-
-            // do not update the chart here
-            // or the chart will flip-flop when it is the master
-            // of a selection sync and another chart becomes
-            // the new master
+        // add our min
+        t[uuid] = min;
 
-            if(dont_update !== true && this.isVisible() === true) {
-                this.updateChart();
+        // find the common min
+        let m = min;
+        // for (let i in t) {
+        //     if (t.hasOwnProperty(i) && t[i] < m) m = t[i];
+        // }
+        for (const ti of Object.values(t)) {
+            if (ti < m) {
+                m = ti;
             }
-        };
+        }
 
-        this.updateChartPanOrZoom = function(after, before, callback) {
-            var logme = 'updateChartPanOrZoom(' + after + ', ' + before + '): ';
-            var ret = true;
+        //state.log('commonMin ' + state.tmp.__commonMin + ' updated: ' + m);
+        this.latest[name] = m;
+        return m;
+    }
+};
 
-            NETDATA.globalPanAndZoom.delay();
-            NETDATA.globalSelectionSync.delay();
+NETDATA.commonMax = {
+    keys: {},
+    latest: {},
 
-            if(this.debug === true)
-                this.log(logme);
+    globalReset: function () {
+        this.keys = {};
+        this.latest = {};
+    },
 
-            if(before < after) {
-                if(this.debug === true)
-                    this.log(logme + 'flipped parameters, rejecting it.');
+    get: function (state) {
+        if (typeof state.tmp.__commonMax === 'undefined') {
+            // get the commonMax setting
+            state.tmp.__commonMax = NETDATA.dataAttribute(state.element, 'common-max', null);
+        }
 
-                return false;
-            }
+        let max = state.data.max;
+        let name = state.tmp.__commonMax;
 
-            if(typeof this.fixed_min_duration === 'undefined')
-                this.fixed_min_duration = Math.round((this.chartWidth() / 30) * this.chart.update_every * 1000);
+        if (name === null) {
+            // we don't need commonMax
+            //state.log('no need for commonMax');
+            return max;
+        }
 
-            var min_duration = this.fixed_min_duration;
-            var current_duration = Math.round(this.view_before - this.view_after);
+        let t = this.keys[name];
+        if (typeof t === 'undefined') {
+            // add our commonMax
+            this.keys[name] = {};
+            t = this.keys[name];
+        }
 
-            // round the numbers
-            after = Math.round(after);
-            before = Math.round(before);
+        let uuid = state.uuid;
+        if (typeof t[uuid] !== 'undefined') {
+            if (t[uuid] === max) {
+                //state.log('commonMax ' + state.tmp.__commonMax + ' not changed: ' + this.latest[name]);
+                return this.latest[name];
+            } else if (max > this.latest[name]) {
+                //state.log('commonMax ' + state.tmp.__commonMax + ' increased: ' + max);
+                t[uuid] = max;
+                this.latest[name] = max;
+                return max;
+            }
+        }
 
-            // align them to update_every
-            // stretching them further away
-            after -= after % this.data_update_every;
-            before += this.data_update_every - (before % this.data_update_every);
+        // add our max
+        t[uuid] = max;
 
-            // the final wanted duration
-            var wanted_duration = before - after;
+        // find the common max
+        let m = max;
+        // for (let i in t) {
+        //     if (t.hasOwnProperty(i) && t[i] > m) m = t[i];
+        // }
+        for (const ti of Object.values(t)) {
+            if (ti > m) {
+                m = ti;
+            }
+        }
 
-            // to allow panning, accept just a point below our minimum
-            if((current_duration - this.data_update_every) < min_duration)
-                min_duration = current_duration - this.data_update_every;
+        //state.log('commonMax ' + state.tmp.__commonMax + ' updated: ' + m);
+        this.latest[name] = m;
+        return m;
+    }
+};
 
-            // we do it, but we adjust to minimum size and return false
-            // when the wanted size is below the current and the minimum
-            // and we zoom
-            if(wanted_duration < current_duration && wanted_duration < min_duration) {
-                if(this.debug === true)
-                    this.log(logme + 'too small: min_duration: ' + (min_duration / 1000).toString() + ', wanted: ' + (wanted_duration / 1000).toString());
+NETDATA.commonColors = {
+    keys: {},
 
-                min_duration = this.fixed_min_duration;
+    globalReset: function () {
+        this.keys = {};
+    },
 
-                var dt = (min_duration - wanted_duration) / 2;
-                before += dt;
-                after -= dt;
-                wanted_duration = before - after;
-                ret = false;
-            }
+    get: function (state, label) {
+        let ret = this.refill(state);
 
-            var tolerance = this.data_update_every * 2;
-            var movement = Math.abs(before - this.view_before);
+        if (typeof ret.assigned[label] === 'undefined') {
+            ret.assigned[label] = ret.available.shift();
+        }
 
-            if(Math.abs(current_duration - wanted_duration) <= tolerance && movement <= tolerance && ret === true) {
-                if(this.debug === true)
-                    this.log(logme + 'REJECTING UPDATE: current/min duration: ' + (current_duration / 1000).toString() + '/' + (this.fixed_min_duration / 1000).toString() + ', wanted duration: ' + (wanted_duration / 1000).toString() + ', duration diff: ' + (Math.round(Math.abs(current_duration - wanted_duration) / 1000)).toString() + ', movement: ' + (movement / 1000).toString() + ', tolerance: ' + (tolerance / 1000).toString() + ', returning: ' + false);
-                return false;
-            }
+        return ret.assigned[label];
+    },
+
+    refill: function (state) {
+        let ret, len;
 
-            if(this.current.name === 'auto') {
-                this.log(logme + 'caller called me with mode: ' + this.current.name);
-                this.setMode('pan');
+        if (typeof state.tmp.__commonColors === 'undefined') {
+            ret = this.prepare(state);
+        } else {
+            ret = this.keys[state.tmp.__commonColors];
+            if (typeof ret === 'undefined') {
+                ret = this.prepare(state);
             }
+        }
 
-            if(this.debug === true)
-                this.log(logme + 'ACCEPTING UPDATE: current/min duration: ' + (current_duration / 1000).toString() + '/' + (this.fixed_min_duration / 1000).toString() + ', wanted duration: ' + (wanted_duration / 1000).toString() + ', duration diff: ' + (Math.round(Math.abs(current_duration - wanted_duration) / 1000)).toString() + ', movement: ' + (movement / 1000).toString() + ', tolerance: ' + (tolerance / 1000).toString() + ', returning: ' + ret);
+        if (ret.available.length === 0) {
+            if (ret.copy_theme || ret.custom.length === 0) {
+                // copy the theme colors
+                len = NETDATA.themes.current.colors.length;
+                while (len--) {
+                    ret.available.unshift(NETDATA.themes.current.colors[len]);
+                }
+            }
 
-            this.current.force_update_at = Date.now() + NETDATA.options.current.pan_and_zoom_delay;
-            this.current.force_after_ms = after;
-            this.current.force_before_ms = before;
-            NETDATA.globalPanAndZoom.setMaster(this, after, before);
+            // copy the custom colors
+            len = ret.custom.length;
+            while (len--) {
+                ret.available.unshift(ret.custom[len]);
+            }
+        }
 
-            if(ret === true && typeof callback === 'function')
-                callback();
+        state.colors_assigned = ret.assigned;
+        state.colors_available = ret.available;
+        state.colors_custom = ret.custom;
 
-            return ret;
-        };
+        return ret;
+    },
 
-        this.updateChartPanOrZoomAsyncTimeOutId = undefined;
-        this.updateChartPanOrZoomAsync = function(after, before, callback) {
-            NETDATA.globalPanAndZoom.delay();
-            NETDATA.globalSelectionSync.delay();
+    __read_custom_colors: function (state, ret) {
+        // add the user supplied colors
+        let c = NETDATA.dataAttribute(state.element, 'colors', undefined);
+        if (typeof c === 'string' && c.length > 0) {
+            c = c.split(' ');
+            let len = c.length;
 
-            if(NETDATA.globalPanAndZoom.isMaster(this) === false) {
-                this.pauseChart();
-                NETDATA.globalPanAndZoom.setMaster(this, after, before);
-                // NETDATA.globalSelectionSync.stop();
-                NETDATA.globalSelectionSync.setMaster(this);
+            if (len > 0 && c[len - 1] === 'ONLY') {
+                len--;
+                ret.copy_theme = false;
             }
 
-            if(this.updateChartPanOrZoomAsyncTimeOutId)
-                NETDATA.timeout.clear(this.updateChartPanOrZoomAsyncTimeOutId);
-
-            NETDATA.timeout.set(function() {
-                that.updateChartPanOrZoomAsyncTimeOutId = undefined;
-                that.updateChartPanOrZoom(after, before, callback);
-            }, 0);
-        };
-
-        var __unitsConversionLastUnits = undefined;
-        var __unitsConversionLastUnitsDesired = undefined;
-        var __unitsConversionLastMin = undefined;
-        var __unitsConversionLastMax = undefined;
-        var __unitsConversion = function(value) { return value; };
-        this.unitsConversionSetup = function(min, max) {
-            if(this.units !== __unitsConversionLastUnits
-                || this.units_desired !== __unitsConversionLastUnitsDesired
-                || min !== __unitsConversionLastMin
-                || max !== __unitsConversionLastMax) {
-
-                __unitsConversionLastUnits = this.units;
-                __unitsConversionLastUnitsDesired = this.units_desired;
-                __unitsConversionLastMin = min;
-                __unitsConversionLastMax = max;
-
-                __unitsConversion = NETDATA.unitsConversion.get(this.uuid, min, max, this.units, this.units_desired, this.units_common, function (units) {
-                    // console.log('switching units from ' + that.units.toString() + ' to ' + units.toString());
-                    that.units_current = units;
-                    that.legendSetUnitsString(that.units_current);
-                });
+            while (len--) {
+                ret.custom.unshift(c[len]);
             }
-        };
+        }
+    },
 
-        var __legendFormatValueChartDecimalsLastMin = undefined;
-        var __legendFormatValueChartDecimalsLastMax = undefined;
-        var __legendFormatValueChartDecimals = -1;
-        var __intlNumberFormat = null;
-        this.legendFormatValueDecimalsFromMinMax = function(min, max) {
-            if(min === __legendFormatValueChartDecimalsLastMin && max === __legendFormatValueChartDecimalsLastMax)
-                return;
+    prepare: function (state) {
+        let has_custom_colors = false;
 
-            this.unitsConversionSetup(min, max);
-            if(__unitsConversion !== null) {
-                min = __unitsConversion(min);
-                max = __unitsConversion(max);
+        if (typeof state.tmp.__commonColors === 'undefined') {
+            let defname = state.chart.context;
 
-                if(typeof min !== 'number' || typeof max !== 'number')
-                    return;
+            // if this chart has data-colors=""
+            // we should use the chart uuid as the default key (private palette)
+            // (data-common-colors="NAME" will be used anyways)
+            let c = NETDATA.dataAttribute(state.element, 'colors', undefined);
+            if (typeof c === 'string' && c.length > 0) {
+                defname = state.uuid;
+                has_custom_colors = true;
             }
 
-            __legendFormatValueChartDecimalsLastMin = min;
-            __legendFormatValueChartDecimalsLastMax = max;
+            // get the commonColors setting
+            state.tmp.__commonColors = NETDATA.dataAttribute(state.element, 'common-colors', defname);
+        }
 
-            var old = __legendFormatValueChartDecimals;
+        let name = state.tmp.__commonColors;
+        let ret = this.keys[name];
 
-            if(this.data !== null && this.data.min === this.data.max)
-                // it is a fixed number, let the visualizer decide based on the value
-                __legendFormatValueChartDecimals = -1;
+        if (typeof ret === 'undefined') {
+            // add our commonMax
+            this.keys[name] = {
+                assigned: {},       // name-value of dimensions and their colors
+                available: [],      // an array of colors available to be used
+                custom: [],         // the array of colors defined by the user
+                charts: {},         // the charts linked to this
+                copy_theme: true
+            };
+            ret = this.keys[name];
+        }
 
-            else if(this.value_decimal_detail !== -1)
-                // there is an override
-                __legendFormatValueChartDecimals = this.value_decimal_detail;
+        if (typeof ret.charts[state.uuid] === 'undefined') {
+            ret.charts[state.uuid] = state;
 
-            else {
-                // ok, let's calculate the proper number of decimal points
-                var delta;
-
-                if (min === max)
-                    delta = Math.abs(min);
-                else
-                    delta = Math.abs(max - min);
-
-                if (delta > 1000)        __legendFormatValueChartDecimals = 0;
-                else if (delta > 10)     __legendFormatValueChartDecimals = 1;
-                else if (delta > 1)      __legendFormatValueChartDecimals = 2;
-                else if (delta > 0.1)    __legendFormatValueChartDecimals = 2;
-                else if (delta > 0.01)   __legendFormatValueChartDecimals = 4;
-                else if (delta > 0.001)  __legendFormatValueChartDecimals = 5;
-                else if (delta > 0.0001) __legendFormatValueChartDecimals = 6;
-                else                     __legendFormatValueChartDecimals = 7;
-            }
-
-            if(__legendFormatValueChartDecimals !== old) {
-                if(__legendFormatValueChartDecimals < 0)
-                    __intlNumberFormat = null;
-                else
-                    __intlNumberFormat = NETDATA.fastNumberFormat.get(
-                        __legendFormatValueChartDecimals,
-                        __legendFormatValueChartDecimals
-                    );
+            if (has_custom_colors) {
+                this.__read_custom_colors(state, ret);
             }
-        };
+        }
 
-        this.legendFormatValue = function(value) {
-            if(typeof value !== 'number')
-                return '-';
+        return ret;
+    }
+};
 
-            value = __unitsConversion(value);
+// ----------------------------------------------------------------------------------------------------------------
+// Chart Registry
 
-            if(typeof value !== 'number')
-                return value;
+// When multiple charts need the same chart, we avoid downloading it
+// multiple times (and having it in browser memory multiple time)
+// by using this registry.
 
-            if(__intlNumberFormat !== null)
-                return __intlNumberFormat.format(value);
+// Every time we download a chart definition, we save it here with .add()
+// Then we try to get it back with .get(). If that fails, we download it.
 
-            var dmin, dmax;
-            if(this.value_decimal_detail !== -1) {
-                dmin = dmax = this.value_decimal_detail;
-            }
-            else {
-                dmin = 0;
-                var abs = (value < 0) ? -value : value;
-                if (abs > 1000)        dmax = 0;
-                else if (abs > 10)     dmax = 1;
-                else if (abs > 1)      dmax = 2;
-                else if (abs > 0.1)    dmax = 2;
-                else if (abs > 0.01)   dmax = 4;
-                else if (abs > 0.001)  dmax = 5;
-                else if (abs > 0.0001) dmax = 6;
-                else                   dmax = 7;
-            }
-
-            return NETDATA.fastNumberFormat.get(dmin, dmax).format(value);
-        };
+NETDATA.fixHost = function (host) {
+    while (host.slice(-1) === '/') {
+        host = host.substring(0, host.length - 1);
+    }
 
-        this.legendSetLabelValue = function(label, value) {
-            var series = this.element_legend_childs.series[label];
-            if(typeof series === 'undefined') return;
-            if(series.value === null && series.user === null) return;
+    return host;
+};
 
-            /*
-            // this slows down firefox and edge significantly
-            // since it requires to use innerHTML(), instead of innerText()
+NETDATA.chartRegistry = {
+    charts: {},
 
-            // if the value has not changed, skip DOM update
-            //if(series.last === value) return;
+    globalReset: function () {
+        this.charts = {};
+    },
 
-            var s, r;
-            if(typeof value === 'number') {
-                var v = Math.abs(value);
-                s = r = this.legendFormatValue(value);
+    add: function (host, id, data) {
+        if (typeof this.charts[host] === 'undefined') {
+            this.charts[host] = {};
+        }
 
-                if(typeof series.last === 'number') {
-                    if(v > series.last) s += '<i class="fas fa-angle-up" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
-                    else if(v < series.last) s += '<i class="fas fa-angle-down" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
-                    else s += '<i class="fas fa-angle-left" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
-                }
-                else s += '<i class="fas fa-angle-right" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
+        //console.log('added ' + host + '/' + id);
+        this.charts[host][id] = data;
+    },
 
-                series.last = v;
-            }
-            else {
-                if(value === null)
-                    s = r = '';
-                else
-                    s = r = value;
+    get: function (host, id) {
+        if (typeof this.charts[host] === 'undefined') {
+            return null;
+        }
 
-                series.last = value;
-            }
-            */
+        if (typeof this.charts[host][id] === 'undefined') {
+            return null;
+        }
 
-            var s = this.legendFormatValue(value);
+        //console.log('cached ' + host + '/' + id);
+        return this.charts[host][id];
+    },
 
-            // caching: do not update the update to show the same value again
-            if(s === series.last_shown_value) return;
-            series.last_shown_value = s;
+    downloadAll: function (host, callback) {
+        host = NETDATA.fixHost(host);
 
-            if(series.value !== null) series.value.innerText = s;
-            if(series.user !== null) series.user.innerText = s;
-        };
+        let self = this;
 
-        this.legendSetDateString = function(date) {
-            if(this.element_legend_childs.title_date !== null && date !== this.tmp.__last_shown_legend_date) {
-                this.element_legend_childs.title_date.innerText = date;
-                this.tmp.__last_shown_legend_date = date;
-            }
-        };
+        function got_data(h, data, callback) {
+            if (data !== null) {
+                self.charts[h] = data.charts;
 
-        this.legendSetTimeString = function(time) {
-            if(this.element_legend_childs.title_time !== null && time !== this.tmp.__last_shown_legend_time) {
-                this.element_legend_childs.title_time.innerText = time;
-                this.tmp.__last_shown_legend_time = time;
+                // update the server timezone in our options
+                if (typeof data.timezone === 'string') {
+                    NETDATA.options.server_timezone = data.timezone;
+                }
+            } else {
+                NETDATA.error(406, h + '/api/v1/charts');
             }
-        };
 
-        this.legendSetUnitsString = function(units) {
-            if(this.element_legend_childs.title_units !== null && units !== this.tmp.__last_shown_legend_units) {
-                this.element_legend_childs.title_units.innerText = units;
-                this.tmp.__last_shown_legend_units = units;
+            if (typeof callback === 'function') {
+                callback(data);
             }
-        };
-
-        this.legendSetDateLast = {
-            ms: 0,
-            date: undefined,
-            time: undefined
-        };
+        }
 
-        this.legendSetDate = function(ms) {
-            if(typeof ms !== 'number') {
-                this.legendShowUndefined();
-                return;
-            }
+        if (netdataSnapshotData !== null) {
+            got_data(host, netdataSnapshotData.charts, callback);
+        } else {
+            $.ajax({
+                url: host + '/api/v1/charts',
+                async: true,
+                cache: false,
+                xhrFields: {withCredentials: true} // required for the cookie
+            })
+                .done(function (data) {
+                    data = NETDATA.xss.checkOptional('/api/v1/charts', data);
+                    got_data(host, data, callback);
+                })
+                .fail(function () {
+                    NETDATA.error(405, host + '/api/v1/charts');
 
-            if(this.legendSetDateLast.ms !== ms) {
-                var d = new Date(ms);
-                this.legendSetDateLast.ms = ms;
-                this.legendSetDateLast.date = NETDATA.dateTime.localeDateString(d);
-                this.legendSetDateLast.time = NETDATA.dateTime.localeTimeString(d);
-            }
+                    if (typeof callback === 'function') {
+                        callback(null);
+                    }
+                });
+        }
+    }
+};
 
-            this.legendSetDateString(this.legendSetDateLast.date);
-            this.legendSetTimeString(this.legendSetDateLast.time);
-            this.legendSetUnitsString(this.units_current)
-        };
+// ----------------------------------------------------------------------------------------------------------------
+// Global Pan and Zoom on charts
 
-        this.legendShowUndefined = function() {
-            this.legendSetDateString(this.legendPluginModuleString(false));
-            this.legendSetTimeString(this.chart.context.toString());
-            // this.legendSetUnitsString(' ');
+// Using this structure are synchronize all the charts, so that
+// when you pan or zoom one, all others are automatically refreshed
+// to the same timespan.
 
-            if(this.data && this.element_legend_childs.series !== null) {
-                var labels = this.data.dimension_names;
-                var i = labels.length;
-                while(i--) {
-                    var label = labels[i];
+NETDATA.globalPanAndZoom = {
+    seq: 0,                 // timestamp ms
+                            // every time a chart is panned or zoomed
+                            // we set the timestamp here
+                            // then we use it as a sequence number
+                            // to find if other charts are synchronized
+                            // to this time-range
 
-                    if(typeof label === 'undefined' || typeof this.element_legend_childs.series[label] === 'undefined') continue;
-                    this.legendSetLabelValue(label, null);
-                }
-            }
-        };
+    master: null,           // the master chart (state), to which all others
+                            // are synchronized
 
-        this.legendShowLatestValues = function() {
-            if(this.chart === null) return;
-            if(this.selected) return;
+    force_before_ms: null,  // the timespan to sync all other charts
+    force_after_ms: null,
 
-            if(this.data === null || this.element_legend_childs.series === null) {
-                this.legendShowUndefined();
-                return;
-            }
+    callback: null,
 
-            var show_undefined = true;
-            if(Math.abs(this.netdata_last - this.view_before) <= this.data_update_every)
-                show_undefined = false;
+    globalReset: function () {
+        this.clearMaster();
+        this.seq = 0;
+        this.master = null;
+        this.force_after_ms = null;
+        this.force_before_ms = null;
+        this.callback = null;
+    },
 
-            if(show_undefined) {
-                this.legendShowUndefined();
-                return;
-            }
+    delay: function () {
+        if (NETDATA.options.debug.globalPanAndZoom) {
+            console.log('globalPanAndZoom.delay()');
+        }
 
-            this.legendSetDate(this.view_before);
+        NETDATA.options.auto_refresher_stop_until = Date.now() + NETDATA.options.current.global_pan_sync_time;
+    },
 
-            var labels = this.data.dimension_names;
-            var i = labels.length;
-            while(i--) {
-                var label = labels[i];
+    // set a new master
+    setMaster: function (state, after, before) {
+        this.delay();
 
-                if(typeof label === 'undefined') continue;
-                if(typeof this.element_legend_childs.series[label] === 'undefined') continue;
+        // if (NETDATA.options.current.sync_pan_and_zoom === false)
+        //     return;
+        if (!NETDATA.options.current.sync_pan_and_zoom) {
+            return;
+        }
 
-                this.legendSetLabelValue(label, this.data.view_latest_values[i]);
+        if (this.master === null) {
+            if (NETDATA.options.debug.globalPanAndZoom) {
+                console.log('globalPanAndZoom.setMaster(' + state.id + ', ' + after + ', ' + before + ') SET MASTER');
+            }
+        } else if (this.master !== state) {
+            if (NETDATA.options.debug.globalPanAndZoom) {
+                console.log('globalPanAndZoom.setMaster(' + state.id + ', ' + after + ', ' + before + ') CHANGED MASTER');
             }
-        };
 
-        this.legendReset = function() {
-            this.legendShowLatestValues();
-        };
+            this.master.resetChart(true, true);
+        }
 
-        // this should be called just ONCE per dimension per chart
-        this.__chartDimensionColor = function(label) {
-            var c = NETDATA.commonColors.get(this, label);
+        let now = Date.now();
+        this.master = state;
+        this.seq = now;
+        this.force_after_ms = after;
+        this.force_before_ms = before;
 
-            // it is important to maintain a list of colors
-            // for this chart only, since the chart library
-            // uses this to assign colors to dimensions in the same
-            // order the dimension are given to it
-            this.colors.push(c);
+        if (typeof this.callback === 'function') {
+            this.callback(true, after, before);
+        }
+    },
 
-            return c;
-        };
+    // clear the master
+    clearMaster: function () {
+        // if (NETDATA.options.debug.globalPanAndZoom === true)
+        //     console.log('globalPanAndZoom.clearMaster()');
+        if (NETDATA.options.debug.globalPanAndZoom) {
+            console.log('globalPanAndZoom.clearMaster()');
+        }
 
-        this.chartPrepareColorPalette = function() {
-            NETDATA.commonColors.refill(this);
-        };
+        if (this.master !== null) {
+            let st = this.master;
+            this.master = null;
+            st.resetChart();
+        }
 
-        // get the ordered list of chart colors
-        // this includes user defined colors
-        this.chartCustomColors = function() {
-            this.chartPrepareColorPalette();
+        this.master = null;
+        this.seq = 0;
+        this.force_after_ms = null;
+        this.force_before_ms = null;
+        NETDATA.options.auto_refresher_stop_until = 0;
 
-            var colors;
-            if(this.colors_custom.length)
-                colors = this.colors_custom;
-            else
-                colors = this.colors;
+        if (typeof this.callback === 'function') {
+            this.callback(false, 0, 0);
+        }
+    },
 
-            if(this.debug === true) {
-                this.log("chartCustomColors() returns:");
-                this.log(colors);
-            }
+    // is the given state the master of the global
+    // pan and zoom sync?
+    isMaster: function (state) {
+        return (this.master === state);
+    },
 
-            return colors;
-        };
+    // are we currently have a global pan and zoom sync?
+    isActive: function () {
+        return (this.master !== null && this.force_before_ms !== null && this.force_after_ms !== null && this.seq !== 0);
+    },
 
-        // get the ordered list of chart ASSIGNED colors
-        // (this returns only the colors that have been
-        //  assigned to dimensions, prepended with any
-        // custom colors defined)
-        this.chartColors = function() {
-            this.chartPrepareColorPalette();
+    // check if a chart, other than the master
+    // needs to be refreshed, due to the global pan and zoom
+    shouldBeAutoRefreshed: function (state) {
+        if (this.master === null || this.seq === 0) {
+            return false;
+        }
+
+        //if (state.needsRecreation())
+        //  return true;
 
-            if(this.debug === true) {
-                this.log("chartColors() returns:");
-                this.log(this.colors);
+        return (state.tm.pan_and_zoom_seq !== this.seq);
+    }
+};
+
+// ----------------------------------------------------------------------------------------------------------------
+// global chart underlay (time-frame highlighting)
+
+NETDATA.globalChartUnderlay = {
+    callback: null,         // what to call when a highlighted range is setup
+    after: null,            // highlight after this time
+    before: null,           // highlight before this time
+    view_after: null,       // the charts after_ms viewport when the highlight was setup
+    view_before: null,      // the charts before_ms viewport, when the highlight was setup
+    state: null,            // the chart the highlight was setup
+
+    isActive: function () {
+        return (this.after !== null && this.before !== null);
+    },
+
+    hasViewport: function () {
+        return (this.state !== null && this.view_after !== null && this.view_before !== null);
+    },
+
+    init: function (state, after, before, view_after, view_before) {
+        this.state = (typeof state !== 'undefined') ? state : null;
+        this.after = (typeof after !== 'undefined' && after !== null && after > 0) ? after : null;
+        this.before = (typeof before !== 'undefined' && before !== null && before > 0) ? before : null;
+        this.view_after = (typeof view_after !== 'undefined' && view_after !== null && view_after > 0) ? view_after : null;
+        this.view_before = (typeof view_before !== 'undefined' && view_before !== null && view_before > 0) ? view_before : null;
+    },
+
+    setup: function () {
+        if (this.isActive()) {
+            if (this.state === null) {
+                this.state = NETDATA.options.targets[0];
+            }
+
+            if (typeof this.callback === 'function') {
+                this.callback(true, this.after, this.before);
+            }
+        } else {
+            if (typeof this.callback === 'function') {
+                this.callback(false, 0, 0);
             }
+        }
+    },
 
-            return this.colors;
-        };
+    set: function (state, after, before, view_after, view_before) {
+        if (after > before) {
+            let t = after;
+            after = before;
+            before = t;
+        }
 
-        this.legendPluginModuleString = function(withContext) {
-            var str = ' ';
-            var context = '';
+        this.init(state, after, before, view_after, view_before);
 
-            if(typeof this.chart !== 'undefined') {
-                if(withContext && typeof this.chart.context === 'string')
-                    context = this.chart.context;
+        // if (this.hasViewport() === true)
+        //     NETDATA.globalPanAndZoom.setMaster(this.state, this.view_after, this.view_before);
+        if (this.hasViewport()) {
+            NETDATA.globalPanAndZoom.setMaster(this.state, this.view_after, this.view_before);
+        }
 
-                if (typeof this.chart.plugin === 'string' && this.chart.plugin !== '') {
-                    str = this.chart.plugin;
+        this.setup();
+    },
 
-                    if(str.endsWith(".plugin"))
-                        str = str.substring(0, str.length - 7);
+    clear: function () {
+        this.after = null;
+        this.before = null;
+        this.state = null;
+        this.view_after = null;
+        this.view_before = null;
 
-                    if (typeof this.chart.module === 'string' && this.chart.module !== '')
-                        str += ':' + this.chart.module;
+        if (typeof this.callback === 'function') {
+            this.callback(false, 0, 0);
+        }
+    },
 
-                    if (withContext && context !== '')
-                        str += ', ' + context;
-                }
-                else if (withContext && context !== '')
-                    str = context;
+    focus: function () {
+        if (this.isActive() && this.hasViewport()) {
+            if (this.state === null) {
+                this.state = NETDATA.options.targets[0];
             }
 
-            return str;
-        };
+            if (NETDATA.globalPanAndZoom.isMaster(this.state)) {
+                NETDATA.globalPanAndZoom.clearMaster();
+            }
 
-        this.legendResolutionTooltip = function () {
-            if(!this.chart) return '';
+            NETDATA.globalPanAndZoom.setMaster(this.state, this.view_after, this.view_before, true);
+        }
+    }
+};
+
+// ----------------------------------------------------------------------------------------------------------------
+// dimensions selection
+
+// TODO
+// move color assignment to dimensions, here
+
+let dimensionStatus = function (parent, label, name_div, value_div, color) {
+    this.enabled = false;
+    this.parent = parent;
+    this.label = label;
+    this.name_div = null;
+    this.value_div = null;
+    this.color = NETDATA.themes.current.foreground;
+    this.selected = (parent.unselected_count === 0);
+
+    this.setOptions(name_div, value_div, color);
+};
+
+dimensionStatus.prototype.invalidate = function () {
+    this.name_div = null;
+    this.value_div = null;
+    this.enabled = false;
+};
+
+dimensionStatus.prototype.setOptions = function (name_div, value_div, color) {
+    this.color = color;
+
+    if (this.name_div !== name_div) {
+        this.name_div = name_div;
+        this.name_div.title = this.label;
+        this.name_div.style.setProperty('color', this.color, 'important');
+        // if (this.selected === false)
+        if (!this.selected) {
+            this.name_div.className = 'netdata-legend-name not-selected';
+        } else {
+            this.name_div.className = 'netdata-legend-name selected';
+        }
+    }
 
-            var collected = this.chart.update_every;
-            var viewed = (this.data)?this.data.view_update_every:collected;
+    if (this.value_div !== value_div) {
+        this.value_div = value_div;
+        this.value_div.title = this.label;
+        this.value_div.style.setProperty('color', this.color, 'important');
+        if (this.selected === false) {
+            this.value_div.className = 'netdata-legend-value not-selected';
+        } else {
+            this.value_div.className = 'netdata-legend-value selected';
+        }
+    }
 
-            if(collected === viewed)
-                return "resolution " + NETDATA.seconds4human(collected);
+    this.enabled = true;
+    this.setHandler();
+};
 
-            return "resolution " + NETDATA.seconds4human(viewed) + ", collected every " + NETDATA.seconds4human(collected);
-        };
+dimensionStatus.prototype.setHandler = function () {
+    // if (this.enabled === false) return;
+    if (!this.enabled) {
+        return;
+    }
 
-        this.legendUpdateDOM = function() {
-            var needed = false, dim, keys, len, i;
+    let ds = this;
 
-            // check that the legend DOM is up to date for the downloaded dimensions
-            if(typeof this.element_legend_childs.series !== 'object' || this.element_legend_childs.series === null) {
-                // this.log('the legend does not have any series - requesting legend update');
-                needed = true;
-            }
-            else if(this.data === null) {
-                // this.log('the chart does not have any data - requesting legend update');
-                needed = true;
-            }
-            else if(typeof this.element_legend_childs.series.labels_key === 'undefined') {
-                needed = true;
-            }
-            else {
-                var labels = this.data.dimension_names.toString();
-                if(labels !== this.element_legend_childs.series.labels_key) {
-                    needed = true;
+    // this.name_div.onmousedown = this.value_div.onmousedown = function(e) {
+    this.name_div.onclick = this.value_div.onclick = function (e) {
+        e.preventDefault();
+        if (ds.isSelected()) {
+            // this is selected
+            if (e.shiftKey || e.ctrlKey) {
+                // control or shift key is pressed -> unselect this (except is none will remain selected, in which case select all)
+                ds.unselect();
 
-                    if(this.debug === true)
-                        this.log('NEW LABELS: "' + labels + '" NOT EQUAL OLD LABELS: "' + this.element_legend_childs.series.labels_key + '"');
+                if (ds.parent.countSelected() === 0) {
+                    ds.parent.selectAll();
                 }
-            }
-
-            if(needed === false) {
-                // make sure colors available
-                this.chartPrepareColorPalette();
-
-                // do we have to update the current values?
-                // we do this, only when the visible chart is current
-                if(Math.abs(this.netdata_last - this.view_before) <= this.data_update_every) {
-                    if(this.debug === true)
-                        this.log('chart is in latest position... updating values on legend...');
-
-                    //var labels = this.data.dimension_names;
-                    //var i = labels.length;
-                    //while(i--)
-                    //  this.legendSetLabelValue(labels[i], this.data.view_latest_values[i]);
+            } else {
+                // no key is pressed -> select only this (except if it is the only selected already, in which case select all)
+                if (ds.parent.countSelected() === 1) {
+                    ds.parent.selectAll();
+                } else {
+                    ds.parent.selectNone();
+                    ds.select();
                 }
-                return;
             }
-
-            if(this.colors === null) {
-                // this is the first time we update the chart
-                // let's assign colors to all dimensions
-                if(this.library.track_colors() === true) {
-                    this.colors = [];
-                    keys = Object.keys(this.chart.dimensions);
-                    len = keys.length;
-                    for(i = 0; i < len ;i++)
-                        NETDATA.commonColors.get(this, this.chart.dimensions[keys[i]].name);
-                }
+        }
+        else {
+            // this is not selected
+            if (e.shiftKey || e.ctrlKey) {
+                // control or shift key is pressed -> select this too
+                ds.select();
+            } else {
+                // no key is pressed -> select only this
+                ds.parent.selectNone();
+                ds.select();
             }
+        }
 
-            // we will re-generate the colors for the chart
-            // based on the dimensions this result has data for
-            this.colors = [];
+        ds.parent.state.redrawChart();
+    }
+};
 
-            if(this.debug === true)
-                this.log('updating Legend DOM');
+dimensionStatus.prototype.select = function () {
+    // if (this.enabled === false) return;
+    if (!this.enabled) {
+        return;
+    }
 
-            // mark all dimensions as invalid
-            this.dimensions_visibility.invalidateAll();
+    this.name_div.className = 'netdata-legend-name selected';
+    this.value_div.className = 'netdata-legend-value selected';
+    this.selected = true;
+};
 
-            var genLabel = function(state, parent, dim, name, count) {
-                var color = state.__chartDimensionColor(name);
+dimensionStatus.prototype.unselect = function () {
+    // if (this.enabled === false) return;
+    if (!this.enabled) {
+        return;
+    }
 
-                var user_element = null;
-                var user_id = NETDATA.dataAttribute(state.element, 'show-value-of-' + name.toLowerCase() + '-at', null);
-                if(user_id === null)
-                    user_id = NETDATA.dataAttribute(state.element, 'show-value-of-' + dim.toLowerCase() + '-at', null);
-                if(user_id !== null) {
-                    user_element = document.getElementById(user_id) || null;
-                    if (user_element === null)
-                        state.log('Cannot find element with id: ' + user_id);
-                }
+    this.name_div.className = 'netdata-legend-name not-selected';
+    this.value_div.className = 'netdata-legend-value hidden';
+    this.selected = false;
+};
+
+dimensionStatus.prototype.isSelected = function () {
+    // return(this.enabled === true && this.selected === true);
+    return this.enabled && this.selected;
+};
+
+// ----------------------------------------------------------------------------------------------------------------
+
+let dimensionsVisibility = function (state) {
+    this.state = state;
+    this.len = 0;
+    this.dimensions = {};
+    this.selected_count = 0;
+    this.unselected_count = 0;
+};
+
+dimensionsVisibility.prototype.dimensionAdd = function (label, name_div, value_div, color) {
+    if (typeof this.dimensions[label] === 'undefined') {
+        this.len++;
+        this.dimensions[label] = new dimensionStatus(this, label, name_div, value_div, color);
+    } else {
+        this.dimensions[label].setOptions(name_div, value_div, color);
+    }
 
-                state.element_legend_childs.series[name] = {
-                    name: document.createElement('span'),
-                    value: document.createElement('span'),
-                    user: user_element,
-                    last: null,
-                    last_shown_value: null
-                };
+    return this.dimensions[label];
+};
 
-                var label = state.element_legend_childs.series[name];
+dimensionsVisibility.prototype.dimensionGet = function (label) {
+    return this.dimensions[label];
+};
 
-                // create the dimension visibility tracking for this label
-                state.dimensions_visibility.dimensionAdd(name, label.name, label.value, color);
+dimensionsVisibility.prototype.invalidateAll = function () {
+    let keys = Object.keys(this.dimensions);
+    let len = keys.length;
+    while (len--) {
+        this.dimensions[keys[len]].invalidate();
+    }
+};
 
-                var rgb = NETDATA.colorHex2Rgb(color);
-                label.name.innerHTML = '<table class="netdata-legend-name-table-'
-                    + state.chart.chart_type
-                    + '" style="background-color: '
-                    + 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + NETDATA.options.current['color_fill_opacity_' + state.chart.chart_type] + ') !important'
-                    + '"><tr class="netdata-legend-name-tr"><td class="netdata-legend-name-td"></td></tr></table>';
+dimensionsVisibility.prototype.selectAll = function () {
+    let keys = Object.keys(this.dimensions);
+    let len = keys.length;
+    while (len--) {
+        this.dimensions[keys[len]].select();
+    }
+};
 
-                var text = document.createTextNode(' ' + name);
-                label.name.appendChild(text);
+dimensionsVisibility.prototype.countSelected = function () {
+    let selected = 0;
+    let keys = Object.keys(this.dimensions);
+    let len = keys.length;
+    while (len--) {
+        if (this.dimensions[keys[len]].isSelected()) {
+            selected++;
+        }
+    }
 
-                if(count > 0)
-                    parent.appendChild(document.createElement('br'));
+    return selected;
+};
 
-                parent.appendChild(label.name);
-                parent.appendChild(label.value);
-            };
+dimensionsVisibility.prototype.selectNone = function () {
+    let keys = Object.keys(this.dimensions);
+    let len = keys.length;
+    while (len--) {
+        this.dimensions[keys[len]].unselect();
+    }
+};
+
+dimensionsVisibility.prototype.selected2BooleanArray = function (array) {
+    let ret = [];
+    this.selected_count = 0;
+    this.unselected_count = 0;
+
+    let len = array.length;
+    while (len--) {
+        let ds = this.dimensions[array[len]];
+        if (typeof ds === 'undefined') {
+            // console.log(array[i] + ' is not found');
+            ret.unshift(false);
+        } else if (ds.isSelected()) {
+            ret.unshift(true);
+            this.selected_count++;
+        } else {
+            ret.unshift(false);
+            this.unselected_count++;
+        }
+    }
 
-            var content = document.createElement('div');
-
-            if(this.element_chart === null) {
-                this.element_chart = document.createElement('div');
-                this.element_chart.id = this.library_name + '-' + this.uuid + '-chart';
-                this.element.appendChild(this.element_chart);
-
-                if(this.hasLegend() === true)
-                    this.element_chart.className = 'netdata-chart-with-legend-right netdata-' + this.library_name + '-chart-with-legend-right';
-                else
-                    this.element_chart.className = ' netdata-chart netdata-' + this.library_name + '-chart';
-            }
-
-            if(this.hasLegend() === true) {
-                if(this.element_legend === null) {
-                    this.element_legend = document.createElement('div');
-                    this.element_legend.className = 'netdata-chart-legend netdata-' + this.library_name + '-legend';
-                    this.element.appendChild(this.element_legend);
-                }
-                else
-                    this.element_legend.innerHTML = '';
-
-                this.element_legend_childs = {
-                    content: content,
-                    resize_handler: null,
-                    toolbox: null,
-                    toolbox_left: null,
-                    toolbox_right: null,
-                    toolbox_reset: null,
-                    toolbox_zoomin: null,
-                    toolbox_zoomout: null,
-                    toolbox_volume: null,
-                    title_date: document.createElement('span'),
-                    title_time: document.createElement('span'),
-                    title_units: document.createElement('span'),
-                    perfect_scroller: document.createElement('div'),
-                    series: {}
-                };
+    if (this.selected_count === 0 && this.unselected_count !== 0) {
+        this.selectAll();
+        return this.selected2BooleanArray(array);
+    }
 
-                if(NETDATA.options.current.legend_toolbox === true && this.library.toolboxPanAndZoom !== null) {
-                    this.element_legend_childs.toolbox = document.createElement('div');
-                    this.element_legend_childs.toolbox_left = document.createElement('div');
-                    this.element_legend_childs.toolbox_right = document.createElement('div');
-                    this.element_legend_childs.toolbox_reset = document.createElement('div');
-                    this.element_legend_childs.toolbox_zoomin = document.createElement('div');
-                    this.element_legend_childs.toolbox_zoomout = document.createElement('div');
-                    this.element_legend_childs.toolbox_volume = document.createElement('div');
+    return ret;
+};
 
-                    var get_pan_and_zoom_step = function(event) {
-                        if (event.ctrlKey)
-                            return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_control;
+// ----------------------------------------------------------------------------------------------------------------
+// date/time conversion
 
-                        else if (event.shiftKey)
-                            return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_shift;
+NETDATA.dateTime = {
+    using_timezone: false,
 
-                        else if (event.altKey)
-                            return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_alt;
+    // these are the old netdata functions
+    // we fallback to these, if the new ones fail
 
-                        else
-                            return NETDATA.options.current.pan_and_zoom_factor;
-                    };
+    localeDateStringNative: function (d) {
+        return d.toLocaleDateString();
+    },
 
-                    this.element_legend_childs.toolbox.className += ' netdata-legend-toolbox';
-                    this.element.appendChild(this.element_legend_childs.toolbox);
+    localeTimeStringNative: function (d) {
+        return d.toLocaleTimeString();
+    },
 
-                    this.element_legend_childs.toolbox_left.className += ' netdata-legend-toolbox-button';
-                    this.element_legend_childs.toolbox_left.innerHTML = NETDATA.icons.left;
-                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_left);
-                    this.element_legend_childs.toolbox_left.onclick = function(e) {
-                        e.preventDefault();
+    xAxisTimeStringNative: function (d) {
+        return NETDATA.zeropad(d.getHours()) + ":"
+            + NETDATA.zeropad(d.getMinutes()) + ":"
+            + NETDATA.zeropad(d.getSeconds());
+    },
 
-                        var step = (that.view_before - that.view_after) * get_pan_and_zoom_step(e);
-                        var before = that.view_before - step;
-                        var after = that.view_after - step;
-                        if(after >= that.netdata_first)
-                            that.library.toolboxPanAndZoom(that, after, before);
-                    };
-                    if(NETDATA.options.current.show_help === true)
-                        $(this.element_legend_childs.toolbox_left).popover({
-                        container: "body",
-                        animation: false,
-                        html: true,
-                        trigger: 'hover',
-                        placement: 'bottom',
-                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
-                        title: 'Pan Left',
-                        content: 'Pan the chart to the left. You can also <b>drag it</b> with your mouse or your finger (on touch devices).<br/><small>Help can be disabled from the settings.</small>'
-                    });
+    // initialize the new date/time conversion
+    // functions.
+    // if this fails, we fallback to the above
+    init: function (timezone) {
+        //console.log('init with timezone: ' + timezone);
 
+        // detect browser timezone
+        try {
+            NETDATA.options.browser_timezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
+        } catch (e) {
+            console.log('failed to detect browser timezone: ' + e.toString());
+            NETDATA.options.browser_timezone = 'cannot-detect-it';
+        }
 
-                    this.element_legend_childs.toolbox_reset.className += ' netdata-legend-toolbox-button';
-                    this.element_legend_childs.toolbox_reset.innerHTML = NETDATA.icons.reset;
-                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_reset);
-                    this.element_legend_childs.toolbox_reset.onclick = function(e) {
-                        e.preventDefault();
-                        NETDATA.resetAllCharts(that);
-                    };
-                    if(NETDATA.options.current.show_help === true)
-                        $(this.element_legend_childs.toolbox_reset).popover({
-                        container: "body",
-                        animation: false,
-                        html: true,
-                        trigger: 'hover',
-                        placement: 'bottom',
-                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
-                        title: 'Chart Reset',
-                        content: 'Reset all the charts to their default auto-refreshing state. You can also <b>double click</b> the chart contents with your mouse or your finger (on touch devices).<br/><small>Help can be disabled from the settings.</small>'
-                    });
+        let ret = false;
 
-                    this.element_legend_childs.toolbox_right.className += ' netdata-legend-toolbox-button';
-                    this.element_legend_childs.toolbox_right.innerHTML = NETDATA.icons.right;
-                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_right);
-                    this.element_legend_childs.toolbox_right.onclick = function(e) {
-                        e.preventDefault();
-                        var step = (that.view_before - that.view_after) * get_pan_and_zoom_step(e);
-                        var before = that.view_before + step;
-                        var after = that.view_after + step;
-                        if(before <= that.netdata_last)
-                            that.library.toolboxPanAndZoom(that, after, before);
-                    };
-                    if(NETDATA.options.current.show_help === true)
-                        $(this.element_legend_childs.toolbox_right).popover({
-                        container: "body",
-                        animation: false,
-                        html: true,
-                        trigger: 'hover',
-                        placement: 'bottom',
-                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
-                        title: 'Pan Right',
-                        content: 'Pan the chart to the right. You can also <b>drag it</b> with your mouse or your finger (on touch devices).<br/><small>Help, can be disabled from the settings.</small>'
-                    });
+        try {
+            let dateOptions = {
+                localeMatcher: 'best fit',
+                formatMatcher: 'best fit',
+                weekday: 'short',
+                year: 'numeric',
+                month: 'short',
+                day: '2-digit'
+            };
 
+            let timeOptions = {
+                localeMatcher: 'best fit',
+                hour12: false,
+                formatMatcher: 'best fit',
+                hour: '2-digit',
+                minute: '2-digit',
+                second: '2-digit'
+            };
 
-                    this.element_legend_childs.toolbox_zoomin.className += ' netdata-legend-toolbox-button';
-                    this.element_legend_childs.toolbox_zoomin.innerHTML = NETDATA.icons.zoomIn;
-                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_zoomin);
-                    this.element_legend_childs.toolbox_zoomin.onclick = function(e) {
-                        e.preventDefault();
-                        var dt = ((that.view_before - that.view_after) * (get_pan_and_zoom_step(e) * 0.8) / 2);
-                        var before = that.view_before - dt;
-                        var after = that.view_after + dt;
-                        that.library.toolboxPanAndZoom(that, after, before);
-                    };
-                    if(NETDATA.options.current.show_help === true)
-                        $(this.element_legend_childs.toolbox_zoomin).popover({
-                        container: "body",
-                        animation: false,
-                        html: true,
-                        trigger: 'hover',
-                        placement: 'bottom',
-                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
-                        title: 'Chart Zoom In',
-                        content: 'Zoom in the chart. You can also press SHIFT and select an area of the chart, or press SHIFT or ALT and use the mouse wheel or 2-finger touchpad scroll to zoom in or out.<br/><small>Help, can be disabled from the settings.</small>'
-                    });
+            let xAxisOptions = {
+                localeMatcher: 'best fit',
+                hour12: false,
+                formatMatcher: 'best fit',
+                hour: '2-digit',
+                minute: '2-digit',
+                second: '2-digit'
+            };
 
-                    this.element_legend_childs.toolbox_zoomout.className += ' netdata-legend-toolbox-button';
-                    this.element_legend_childs.toolbox_zoomout.innerHTML = NETDATA.icons.zoomOut;
-                    this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_zoomout);
-                    this.element_legend_childs.toolbox_zoomout.onclick = function(e) {
-                        e.preventDefault();
-                        var dt = (((that.view_before - that.view_after) / (1.0 - (get_pan_and_zoom_step(e) * 0.8)) - (that.view_before - that.view_after)) / 2);
-                        var before = that.view_before + dt;
-                        var after = that.view_after - dt;
+            if (typeof timezone === 'string' && timezone !== '' && timezone !== 'default') {
+                dateOptions.timeZone = timezone;
+                timeOptions.timeZone = timezone;
+                timeOptions.timeZoneName = 'short';
+                xAxisOptions.timeZone = timezone;
+                this.using_timezone = true;
+            } else {
+                timezone = 'default';
+                this.using_timezone = false;
+            }
 
-                        that.library.toolboxPanAndZoom(that, after, before);
-                    };
-                    if(NETDATA.options.current.show_help === true)
-                        $(this.element_legend_childs.toolbox_zoomout).popover({
-                        container: "body",
-                        animation: false,
-                        html: true,
-                        trigger: 'hover',
-                        placement: 'bottom',
-                        delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
-                        title: 'Chart Zoom Out',
-                        content: 'Zoom out the chart. You can also press SHIFT or ALT and use the mouse wheel, or 2-finger touchpad scroll to zoom in or out.<br/><small>Help, can be disabled from the settings.</small>'
-                    });
+            this.dateFormat = new Intl.DateTimeFormat(navigator.language, dateOptions);
+            this.timeFormat = new Intl.DateTimeFormat(navigator.language, timeOptions);
+            this.xAxisFormat = new Intl.DateTimeFormat(navigator.language, xAxisOptions);
 
-                    //this.element_legend_childs.toolbox_volume.className += ' netdata-legend-toolbox-button';
-                    //this.element_legend_childs.toolbox_volume.innerHTML = '<i class="fas fa-sort-amount-down"></i>';
-                    //this.element_legend_childs.toolbox_volume.title = 'Visible Volume';
-                    //this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_volume);
-                    //this.element_legend_childs.toolbox_volume.onclick = function(e) {
-                        //e.preventDefault();
-                        //alert('clicked toolbox_volume on ' + that.id);
-                    //}
-                }
-
-                if(NETDATA.options.current.resize_charts === true) {
-                    this.element_legend_childs.resize_handler = document.createElement('div');
-
-                    this.element_legend_childs.resize_handler.className += " netdata-legend-resize-handler";
-                    this.element_legend_childs.resize_handler.innerHTML = NETDATA.icons.resize;
-                    this.element.appendChild(this.element_legend_childs.resize_handler);
-                    if (NETDATA.options.current.show_help === true)
-                        $(this.element_legend_childs.resize_handler).popover({
-                            container: "body",
-                            animation: false,
-                            html: true,
-                            trigger: 'hover',
-                            placement: 'bottom',
-                            delay: {
-                                show: NETDATA.options.current.show_help_delay_show_ms,
-                                hide: NETDATA.options.current.show_help_delay_hide_ms
-                            },
-                            title: 'Chart Resize',
-                            content: 'Drag this point with your mouse or your finger (on touch devices), to resize the chart vertically. You can also <b>double click it</b> or <b>double tap it</b> to reset between 2 states: the default and the one that fits all the values.<br/><small>Help, can be disabled from the settings.</small>'
-                        });
+            this.localeDateString = function (d) {
+                return this.dateFormat.format(d);
+            };
 
-                    // mousedown event
-                    this.element_legend_childs.resize_handler.onmousedown =
-                        function (e) {
-                            that.resizeHandler(e);
-                        };
+            this.localeTimeString = function (d) {
+                return this.timeFormat.format(d);
+            };
 
-                    // touchstart event
-                    this.element_legend_childs.resize_handler.addEventListener('touchstart', function (e) {
-                        that.resizeHandler(e);
-                    }, false);
-                }
+            this.xAxisTimeString = function (d) {
+                return this.xAxisFormat.format(d);
+            };
 
-                if(this.chart) {
-                    this.element_legend_childs.title_date.title = this.legendPluginModuleString(true);
-                    this.element_legend_childs.title_time.title = this.legendResolutionTooltip();
-                }
+            //let d = new Date();
+            //let t = this.dateFormat.format(d) + ' ' + this.timeFormat.format(d) + ' ' + this.xAxisFormat.format(d);
 
-                this.element_legend_childs.title_date.className += " netdata-legend-title-date";
-                this.element_legend.appendChild(this.element_legend_childs.title_date);
-                this.tmp.__last_shown_legend_date = undefined;
+            ret = true;
+        } catch (e) {
+            console.log('Cannot setup Date/Time formatting: ' + e.toString());
 
-                this.element_legend.appendChild(document.createElement('br'));
+            timezone = 'default';
+            this.localeDateString = this.localeDateStringNative;
+            this.localeTimeString = this.localeTimeStringNative;
+            this.xAxisTimeString = this.xAxisTimeStringNative;
+            this.using_timezone = false;
 
-                this.element_legend_childs.title_time.className += " netdata-legend-title-time";
-                this.element_legend.appendChild(this.element_legend_childs.title_time);
-                this.tmp.__last_shown_legend_time = undefined;
+            ret = false;
+        }
 
-                this.element_legend.appendChild(document.createElement('br'));
+        // save it
+        //console.log('init setOption timezone: ' + timezone);
+        NETDATA.setOption('timezone', timezone);
 
-                this.element_legend_childs.title_units.className += " netdata-legend-title-units";
-                this.element_legend_childs.title_units.innerText = this.units_current;
-                this.element_legend.appendChild(this.element_legend_childs.title_units);
-                this.tmp.__last_shown_legend_units = undefined;
+        return ret;
+    }
+};
+NETDATA.dateTime.init(NETDATA.options.current.timezone);
+
+// ----------------------------------------------------------------------------------------------------------------
+// global selection sync
+
+NETDATA.globalSelectionSync = {
+    state: null,
+    dont_sync_before: 0,
+    last_t: 0,
+    slaves: [],
+    timeout_id: undefined,
+
+    globalReset: function () {
+        this.stop();
+        this.state = null;
+        this.dont_sync_before = 0;
+        this.last_t = 0;
+        this.slaves = [];
+        this.timeout_id = undefined;
+    },
+
+    active: function () {
+        return (this.state !== null);
+    },
+
+    // return true if global selection sync can be enabled now
+    enabled: function () {
+        // console.log('enabled()');
+        // can we globally apply selection sync?
+        // if (NETDATA.options.current.sync_selection === false) {
+        if (!NETDATA.options.current.sync_selection) {
+            return false;
+        }
 
-                this.element_legend.appendChild(document.createElement('br'));
+        return (this.dont_sync_before <= Date.now());
+    },
 
-                this.element_legend_childs.perfect_scroller.className = 'netdata-legend-series';
-                this.element_legend.appendChild(this.element_legend_childs.perfect_scroller);
+    // set the global selection sync master
+    setMaster: function (state) {
+        // if (this.enabled() === false) {
+        if (!this.enabled()) {
+            this.stop();
+            return;
+        }
 
-                content.className = 'netdata-legend-series-content';
-                this.element_legend_childs.perfect_scroller.appendChild(content);
+        if (this.state === state) {
+            return;
+        }
 
-                this.element_legend_childs.content = content;
+        if (this.state !== null) {
+            this.stop();
+        }
 
-                if(NETDATA.options.current.show_help === true)
-                    $(content).popover({
-                    container: "body",
-                    animation: false,
-                    html: true,
-                    trigger: 'hover',
-                    placement: 'bottom',
-                    title: 'Chart Legend',
-                    delay: { show: NETDATA.options.current.show_help_delay_show_ms, hide: NETDATA.options.current.show_help_delay_hide_ms },
-                    content: 'You can click or tap on the values or the labels to select dimensions. By pressing SHIFT or CONTROL, you can enable or disable multiple dimensions.<br/><small>Help, can be disabled from the settings.</small>'
-                });
-            }
-            else {
-                this.element_legend_childs = {
-                    content: content,
-                    resize_handler: null,
-                    toolbox: null,
-                    toolbox_left: null,
-                    toolbox_right: null,
-                    toolbox_reset: null,
-                    toolbox_zoomin: null,
-                    toolbox_zoomout: null,
-                    toolbox_volume: null,
-                    title_date: null,
-                    title_time: null,
-                    title_units: null,
-                    perfect_scroller: null,
-                    series: {}
-                };
+        if (NETDATA.options.debug.globalSelectionSync) {
+            console.log('globalSelectionSync.setMaster(' + state.id + ')');
+        }
+
+        state.selected = true;
+        this.state = state;
+        this.last_t = 0;
+
+        // find all slaves
+        let targets = NETDATA.intersectionObserver.targets();
+        this.slaves = [];
+        let len = targets.length;
+        while (len--) {
+            let st = targets[len];
+            if (this.state !== st && st.globalSelectionSyncIsEligible()) {
+                this.slaves.push(st);
             }
+        }
 
-            if(this.data) {
-                this.element_legend_childs.series.labels_key = this.data.dimension_names.toString();
-                if(this.debug === true)
-                    this.log('labels from data: "' + this.element_legend_childs.series.labels_key + '"');
+        // this.delay(100);
+    },
 
-                for(i = 0, len = this.data.dimension_names.length; i < len ;i++) {
-                    genLabel(this, content, this.data.dimension_ids[i], this.data.dimension_names[i], i);
-                }
+    // stop global selection sync
+    stop: function () {
+        if (this.state !== null) {
+            if (NETDATA.options.debug.globalSelectionSync) {
+                console.log('globalSelectionSync.stop()');
             }
-            else {
-                var tmp = [];
-                keys = Object.keys(this.chart.dimensions);
-                for(i = 0, len = keys.length; i < len ;i++) {
-                    dim = keys[i];
-                    tmp.push(this.chart.dimensions[dim].name);
-                    genLabel(this, content, dim, this.chart.dimensions[dim].name, i);
-                }
-                this.element_legend_childs.series.labels_key = tmp.toString();
-                if(this.debug === true)
-                    this.log('labels from chart: "' + this.element_legend_childs.series.labels_key + '"');
-            }
-
-            // create a hidden div to be used for hidding
-            // the original legend of the chart library
-            var el = document.createElement('div');
-            if(this.element_legend !== null)
-                this.element_legend.appendChild(el);
-            el.style.display = 'none';
-
-            this.element_legend_childs.hidden = document.createElement('div');
-            el.appendChild(this.element_legend_childs.hidden);
-
-            if(this.element_legend_childs.perfect_scroller !== null) {
-                Ps.initialize(this.element_legend_childs.perfect_scroller, {
-                    wheelSpeed: 0.2,
-                    wheelPropagation: true,
-                    swipePropagation: true,
-                    minScrollbarLength: null,
-                    maxScrollbarLength: null,
-                    useBothWheelAxes: false,
-                    suppressScrollX: true,
-                    suppressScrollY: false,
-                    scrollXMarginOffset: 0,
-                    scrollYMarginOffset: 0,
-                    theme: 'default'
-                });
-                Ps.update(this.element_legend_childs.perfect_scroller);
+
+            let len = this.slaves.length;
+            while (len--) {
+                this.slaves[len].clearSelection();
             }
 
-            this.legendShowLatestValues();
-        };
+            this.state.clearSelection();
+
+            this.last_t = 0;
+            this.slaves = [];
+            this.state = null;
+        }
+    },
 
-        this.hasLegend = function() {
-            if(typeof this.tmp.___hasLegendCache___ !== 'undefined')
-                return this.tmp.___hasLegendCache___;
+    // delay global selection sync for some time
+    delay: function (ms) {
+        if (NETDATA.options.current.sync_selection) {
+            // if (NETDATA.options.debug.globalSelectionSync === true) {
+            if (NETDATA.options.debug.globalSelectionSync) {
+                console.log('globalSelectionSync.delay()');
+            }
 
-            var leg = false;
-            if(this.library && this.library.legend(this) === 'right-side')
-                leg = true;
+            if (typeof ms === 'number') {
+                this.dont_sync_before = Date.now() + ms;
+            } else {
+                this.dont_sync_before = Date.now() + NETDATA.options.current.sync_selection_delay;
+            }
+        }
+    },
 
-            this.tmp.___hasLegendCache___ = leg;
-            return leg;
-        };
+    __syncSlaves: function () {
+        // if (NETDATA.globalSelectionSync.enabled() === true) {
+        if (NETDATA.globalSelectionSync.enabled()) {
+            // if (NETDATA.options.debug.globalSelectionSync === true)
+            if (NETDATA.options.debug.globalSelectionSync) {
+                console.log('globalSelectionSync.__syncSlaves()');
+            }
 
-        this.legendWidth = function() {
-            return (this.hasLegend())?140:0;
-        };
+            let t = NETDATA.globalSelectionSync.last_t;
+            let len = NETDATA.globalSelectionSync.slaves.length;
+            while (len--) {
+                NETDATA.globalSelectionSync.slaves[len].setSelection(t);
+            }
 
-        this.legendHeight = function() {
-            return $(this.element).height();
-        };
+            this.timeout_id = undefined;
+        }
+    },
 
-        this.chartWidth = function() {
-            return $(this.element).width() - this.legendWidth();
-        };
+    // sync all the visible charts to the given time
+    // this is to be called from the chart libraries
+    sync: function (state, t) {
+        // if (NETDATA.options.current.sync_selection === true) {
+        if (NETDATA.options.current.sync_selection) {
+            // if (NETDATA.options.debug.globalSelectionSync === true)
+            if (NETDATA.options.debug.globalSelectionSync) {
+                console.log('globalSelectionSync.sync(' + state.id + ', ' + t.toString() + ')');
+            }
 
-        this.chartHeight = function() {
-            return $(this.element).height();
-        };
+            this.setMaster(state);
 
-        this.chartPixelsPerPoint = function() {
-            // force an options provided detail
-            var px = this.pixels_per_point;
+            if (t === this.last_t) {
+                return;
+            }
 
-            if(this.library && px < this.library.pixels_per_point(this))
-                px = this.library.pixels_per_point(this);
+            this.last_t = t;
 
-            if(px < NETDATA.options.current.pixels_per_point)
-                px = NETDATA.options.current.pixels_per_point;
+            if (state.foreign_element_selection !== null) {
+                state.foreign_element_selection.innerText = NETDATA.dateTime.localeDateString(t) + ' ' + NETDATA.dateTime.localeTimeString(t);
+            }
 
-            return px;
-        };
+            if (this.timeout_id) {
+                NETDATA.timeout.clear(this.timeout_id);
+            }
 
-        this.needsRecreation = function() {
-            var ret = (
-                    this.chart_created === true
-                    && this.library
-                    && this.library.autoresize() === false
-                    && this.tm.last_resized < NETDATA.options.last_page_resize
-                );
+            this.timeout_id = NETDATA.timeout.set(this.__syncSlaves, 0);
+        }
+    }
+};
 
-            if(this.debug === true)
-                this.log('needsRecreation(): ' + ret.toString() + ', chart_created = ' + this.chart_created.toString());
+NETDATA.intersectionObserver = {
+    observer: null,
+    visible_targets: [],
 
-            return ret;
-        };
+    options: {
+        root: null,
+        rootMargin: "0px",
+        threshold: null
+    },
 
-        this.chartDataUniqueID = function() {
-            return this.id + ',' + this.library_name + ',' + this.dimensions + ',' + this.chartURLOptions();
-        };
+    enabled: function () {
+        return this.observer !== null;
+    },
 
-        this.chartURLOptions = function() {
-            var ret = '';
+    globalReset: function () {
+        if (this.observer !== null) {
+            this.visible_targets = [];
+            this.observer.disconnect();
+            this.init();
+        }
+    },
 
-            if(this.override_options !== null)
-                ret = this.override_options.toString();
-            else
-                ret = this.library.options(this);
+    targets: function () {
+        if (this.enabled() && this.visible_targets.length > 0) {
+            return this.visible_targets;
+        } else {
+            return NETDATA.options.targets;
+        }
+    },
 
-            if(this.append_options !== null)
-                ret += '%7C' + this.append_options.toString();
+    switchChartVisibility: function () {
+        let old = this.__visibilityRatioOld;
 
-            ret += '%7C' + 'jsonwrap';
+        if (old !== this.__visibilityRatio) {
+            if (old === 0 && this.__visibilityRatio > 0) {
+                this.unhideChart();
+            } else if (old > 0 && this.__visibilityRatio === 0) {
+                this.hideChart();
+            }
 
-            if(NETDATA.options.current.eliminate_zero_dimensions === true)
-                ret += '%7C' + 'nonzero';
+            this.__visibilityRatioOld = this.__visibilityRatio;
+        }
+    },
 
-            return ret;
-        };
+    handler: function (entries, observer) {
+        entries.forEach(function (entry) {
+            let state = NETDATA.chartState(entry.target);
 
-        this.chartURL = function() {
-            var after, before, points_multiplier = 1;
-            if(NETDATA.globalPanAndZoom.isActive()) {
-                if(this.current.force_before_ms !== null && this.current.force_after_ms !== null) {
-                    this.tm.pan_and_zoom_seq = 0;
-
-                    before = Math.round(this.current.force_before_ms / 1000);
-                    after  = Math.round(this.current.force_after_ms / 1000);
-                    this.view_after = after * 1000;
-                    this.view_before = before * 1000;
-
-                    if(NETDATA.options.current.pan_and_zoom_data_padding === true) {
-                        this.requested_padding = Math.round((before - after) / 2);
-                        after -= this.requested_padding;
-                        before += this.requested_padding;
-                        this.requested_padding *= 1000;
-                        points_multiplier = 2;
+            let idx;
+            if (entry.intersectionRatio > 0) {
+                idx = NETDATA.intersectionObserver.visible_targets.indexOf(state);
+                if (idx === -1) {
+                    if (NETDATA.scrollUp) {
+                        NETDATA.intersectionObserver.visible_targets.push(state);
+                    } else {
+                        NETDATA.intersectionObserver.visible_targets.unshift(state);
                     }
-
-                    this.current.force_before_ms = null;
-                    this.current.force_after_ms = null;
                 }
-                else {
-                    this.tm.pan_and_zoom_seq = NETDATA.globalPanAndZoom.seq;
+                else if (state.__visibilityRatio === 0) {
+                    state.log("was not visible until now, but was already in visible_targets");
+                }
+            } else {
+                idx = NETDATA.intersectionObserver.visible_targets.indexOf(state);
+                if (idx !== -1) {
+                    NETDATA.intersectionObserver.visible_targets.splice(idx, 1);
+                } else if (state.__visibilityRatio > 0) {
+                    state.log("was visible, but not found in visible_targets");
+                }
+            }
 
-                    after = Math.round(NETDATA.globalPanAndZoom.force_after_ms / 1000);
-                    before = Math.round(NETDATA.globalPanAndZoom.force_before_ms / 1000);
-                    this.view_after = after * 1000;
-                    this.view_before = before * 1000;
+            state.__visibilityRatio = entry.intersectionRatio;
 
-                    this.requested_padding = null;
-                    points_multiplier = 1;
+            if (NETDATA.options.current.async_on_scroll === false) {
+                if (window.requestIdleCallback) {
+                    window.requestIdleCallback(function () {
+                        NETDATA.intersectionObserver.switchChartVisibility.call(state);
+                    }, {timeout: 100});
+                } else {
+                    NETDATA.intersectionObserver.switchChartVisibility.call(state);
                 }
             }
-            else {
-                this.tm.pan_and_zoom_seq = 0;
+        });
+    },
 
-                before = this.before;
-                after  = this.after;
-                this.view_after = after * 1000;
-                this.view_before = before * 1000;
+    observe: function (state) {
+        if (this.enabled()) {
+            state.__visibilityRatioOld = 0;
+            state.__visibilityRatio = 0;
+            this.observer.observe(state.element);
 
-                this.requested_padding = null;
-                points_multiplier = 1;
-            }
+            state.isVisible = function () {
+                if (NETDATA.options.current.update_only_visible === false) {
+                    return true;
+                }
 
-            this.requested_after = after * 1000;
-            this.requested_before = before * 1000;
+                NETDATA.intersectionObserver.switchChartVisibility.call(this);
 
-            var data_points;
-            if(NETDATA.options.force_data_points !== 0) {
-                data_points = NETDATA.options.force_data_points;
-                this.data_points = data_points;
+                return this.__visibilityRatio > 0;
             }
-            else {
-                this.data_points = this.points || Math.round(this.chartWidth() / this.chartPixelsPerPoint());
-                data_points = this.data_points * points_multiplier;
+        }
+    },
+
+    init: function () {
+        if (typeof netdataIntersectionObserver === 'undefined' || netdataIntersectionObserver) {
+            try {
+                this.observer = new IntersectionObserver(this.handler, this.options);
+            } catch (e) {
+                console.log("IntersectionObserver is not supported on this browser");
+                this.observer = null;
             }
+        }
+        //else {
+        //    console.log("IntersectionObserver is disabled");
+        //}
+    }
+};
+NETDATA.intersectionObserver.init();
 
-            // build the data URL
-            this.data_url = this.host + this.chart.data_url;
-            this.data_url += "&format="  + this.library.format();
-            this.data_url += "&points="  + (data_points).toString();
-            this.data_url += "&group="   + this.method;
-            this.data_url += "&gtime="   + this.gtime;
-            this.data_url += "&options=" + this.chartURLOptions();
+// ----------------------------------------------------------------------------------------------------------------
+// Our state object, where all per-chart values are stored
 
-            if(after)
-                this.data_url += "&after="  + after.toString();
+let chartState = function (element) {
+    this.element = element;
 
-            if(before)
-                this.data_url += "&before=" + before.toString();
+    // IMPORTANT:
+    // all private functions should use 'that', instead of 'this'
+    let that = this;
 
-            if(this.dimensions)
-                this.data_url += "&dimensions=" + this.dimensions;
+    // ============================================================================================================
+    // ERROR HANDLING
 
-            if(NETDATA.options.debug.chart_data_url === true || this.debug === true)
-                this.log('chartURL(): ' + this.data_url + ' WxH:' + this.chartWidth() + 'x' + this.chartHeight() + ' points: ' + data_points.toString() + ' library: ' + this.library_name);
-        };
+    /* error() - private
+     * show an error instead of the chart
+     */
+    let error = function (msg) {
+        let ret = true;
 
-        this.redrawChart = function() {
-            if(this.data !== null)
-                this.updateChartWithData(this.data);
-        };
+        if (typeof netdataErrorCallback === 'function') {
+            ret = netdataErrorCallback('chart', that.id, msg);
+        }
 
-        this.updateChartWithData = function(data) {
-            if(this.debug === true)
-                this.log('updateChartWithData() called.');
+        if (ret) {
+            that.element.innerHTML = that.id + ': ' + msg;
+            that.enabled = false;
+            that.current = that.pan;
+        }
+    };
 
-            // this may force the chart to be re-created
-            resizeChart();
+    // console logging
+    this.log = function (msg) {
+        console.log(this.id + ' (' + this.library_name + ' ' + this.uuid + '): ' + msg);
+    };
 
-            this.data = data;
+    this.debugLog = function (msg) {
+        if (this.debug) {
+            this.log(msg);
+        }
+    };
 
-            var started = Date.now();
-            var view_update_every = data.view_update_every * 1000;
+    // ============================================================================================================
+    // EARLY INITIALIZATION
 
+    // These are variables that should exist even if the chart is never to be rendered.
+    // Be careful what you add here - there may be thousands of charts on the page.
 
-            if(this.data_update_every !== view_update_every) {
-                if(this.element_legend_childs.title_time)
-                    this.element_legend_childs.title_time.title = this.legendResolutionTooltip();
-            }
+    // GUID - a unique identifier for the chart
+    this.uuid = NETDATA.guid();
 
-            // if the result is JSON, find the latest update-every
-            this.data_update_every = view_update_every;
-            this.data_after = data.after * 1000;
-            this.data_before = data.before * 1000;
-            this.netdata_first = data.first_entry * 1000;
-            this.netdata_last = data.last_entry * 1000;
-            this.data_points = data.points;
+    // string - the name of chart
+    this.id = NETDATA.dataAttribute(this.element, 'netdata', undefined);
+    if (typeof this.id === 'undefined') {
+        error("netdata elements need data-netdata");
+        return;
+    }
 
-            data.state = this;
+    // string - the key for localStorage settings
+    this.settings_id = NETDATA.dataAttribute(this.element, 'id', null);
 
-            if(NETDATA.options.current.pan_and_zoom_data_padding === true && this.requested_padding !== null) {
-                if(this.view_after < this.data_after) {
-                    // console.log('adjusting view_after from ' + this.view_after + ' to ' + this.data_after);
-                    this.view_after = this.data_after;
-                }
+    // the user given dimensions of the element
+    this.width = NETDATA.dataAttribute(this.element, 'width', NETDATA.chartDefaults.width);
+    this.height = NETDATA.dataAttribute(this.element, 'height', NETDATA.chartDefaults.height);
+    this.height_original = this.height;
 
-                if(this.view_before > this.data_before) {
-                    // console.log('adjusting view_before from ' + this.view_before + ' to ' + this.data_before);
-                    this.view_before = this.data_before;
-                }
-            }
-            else {
-                this.view_after = this.data_after;
-                this.view_before = this.data_before;
-            }
+    if (this.settings_id !== null) {
+        this.height = NETDATA.localStorageGet('chart_heights.' + this.settings_id, this.height, function (height) {
+            // this is the callback that will be called
+            // if and when the user resets all localStorage variables
+            // to their defaults
 
-            if(this.debug === true) {
-                this.log('UPDATE No ' + this.updates_counter + ' COMPLETED');
+            resizeChartToHeight(height);
+        });
+    }
 
-                if(this.current.force_after_ms)
-                    this.log('STATUS: forced    : ' + (this.current.force_after_ms / 1000).toString() + ' - ' + (this.current.force_before_ms / 1000).toString());
-                else
-                    this.log('STATUS: forced    : unset');
+    // the chart library requested by the user
+    this.library_name = NETDATA.dataAttribute(this.element, 'chart-library', NETDATA.chartDefaults.library);
 
-                this.log('STATUS: requested : ' + (this.requested_after / 1000).toString() + ' - ' + (this.requested_before / 1000).toString());
-                this.log('STATUS: downloaded: ' + (this.data_after / 1000).toString() + ' - ' + (this.data_before / 1000).toString());
-                this.log('STATUS: rendered  : ' + (this.view_after / 1000).toString() + ' - ' + (this.view_before / 1000).toString());
-                this.log('STATUS: points    : ' + (this.data_points).toString());
-            }
+    // check the requested library is available
+    // we don't initialize it here - it will be initialized when
+    // this chart will be first used
+    if (typeof NETDATA.chartLibraries[this.library_name] === 'undefined') {
+        NETDATA.error(402, this.library_name);
+        error('chart library "' + this.library_name + '" is not found');
+        this.enabled = false;
+    } else if (NETDATA.chartLibraries[this.library_name].enabled === false) {
+        NETDATA.error(403, this.library_name);
+        error('chart library "' + this.library_name + '" is not enabled');
+        this.enabled = false;
+    } else {
+        this.library = NETDATA.chartLibraries[this.library_name];
+    }
 
-            if(this.data_points === 0) {
-                noDataToShow();
-                return;
-            }
+    this.auto = {
+        name: 'auto',
+        autorefresh: true,
+        force_update_at: 0, // the timestamp to force the update at
+        force_before_ms: null,
+        force_after_ms: null
+    };
+    this.pan = {
+        name: 'pan',
+        autorefresh: false,
+        force_update_at: 0, // the timestamp to force the update at
+        force_before_ms: null,
+        force_after_ms: null
+    };
+    this.zoom = {
+        name: 'zoom',
+        autorefresh: false,
+        force_update_at: 0, // the timestamp to force the update at
+        force_before_ms: null,
+        force_after_ms: null
+    };
+
+    // this is a pointer to one of the sub-classes below
+    // auto, pan, zoom
+    this.current = this.auto;
+
+    this.running = false;                       // boolean - true when the chart is being refreshed now
+    this.enabled = true;                        // boolean - is the chart enabled for refresh?
+
+    this.force_update_every = null;             // number - overwrite the visualization update frequency of the chart
+
+    this.tmp = {};
+
+    this.foreign_element_before = null;
+    this.foreign_element_after = null;
+    this.foreign_element_duration = null;
+    this.foreign_element_update_every = null;
+    this.foreign_element_selection = null;
+
+    // ============================================================================================================
+    // PRIVATE FUNCTIONS
+
+    // reset the runtime status variables to their defaults
+    const runtimeInit = function () {
+        that.paused = false;                        // boolean - is the chart paused for any reason?
+        that.selected = false;                      // boolean - is the chart shown a selection?
+
+        that.chart_created = false;                 // boolean - is the library.create() been called?
+        that.dom_created = false;                   // boolean - is the chart DOM been created?
+        that.fetching_data = false;                 // boolean - true while we fetch data via ajax
+
+        that.updates_counter = 0;                   // numeric - the number of refreshes made so far
+        that.updates_since_last_unhide = 0;         // numeric - the number of refreshes made since the last time the chart was unhidden
+        that.updates_since_last_creation = 0;       // numeric - the number of refreshes made since the last time the chart was created
+
+        that.tm = {
+            last_initialized: 0,                    // milliseconds - the timestamp it was last initialized
+            last_dom_created: 0,                    // milliseconds - the timestamp its DOM was last created
+            last_mode_switch: 0,                    // milliseconds - the timestamp it switched modes
+
+            last_info_downloaded: 0,                // milliseconds - the timestamp we downloaded the chart
+            last_updated: 0,                        // the timestamp the chart last updated with data
+            pan_and_zoom_seq: 0,                    // the sequence number of the global synchronization
+                                                    // between chart.
+                                                    // Used with NETDATA.globalPanAndZoom.seq
+            last_visible_check: 0,                  // the time we last checked if it is visible
+            last_resized: 0,                        // the time the chart was resized
+            last_hidden: 0,                         // the time the chart was hidden
+            last_unhidden: 0,                       // the time the chart was unhidden
+            last_autorefreshed: 0                   // the time the chart was last refreshed
+        };
 
-            if(this.updates_since_last_creation >= this.library.max_updates_to_recreate()) {
-                if(this.debug === true)
-                    this.log('max updates of ' + this.updates_since_last_creation.toString() + ' reached. Forcing re-generation.');
+        that.data = null;                           // the last data as downloaded from the netdata server
+        that.data_url = 'invalid://';               // string - the last url used to update the chart
+        that.data_points = 0;                       // number - the number of points returned from netdata
+        that.data_after = 0;                        // milliseconds - the first timestamp of the data
+        that.data_before = 0;                       // milliseconds - the last timestamp of the data
+        that.data_update_every = 0;                 // milliseconds - the frequency to update the data
 
-                init('force');
-                return;
-            }
+        that.tmp = {};                              // members that can be destroyed to save memory
+    };
 
-            // check and update the legend
-            this.legendUpdateDOM();
+    // initialize all the variables that are required for the chart to be rendered
+    const lateInitialization = function () {
+        if (typeof that.host !== 'undefined') {
+            return;
+        }
 
-            if(this.chart_created === true
-                && typeof this.library.update === 'function') {
+        // string - the netdata server URL, without any path
+        that.host = NETDATA.dataAttribute(that.element, 'host', NETDATA.serverDefault);
 
-                if(this.debug === true)
-                    this.log('updating chart...');
+        // make sure the host does not end with /
+        // all netdata API requests use absolute paths
+        while (that.host.slice(-1) === '/') {
+            that.host = that.host.substring(0, that.host.length - 1);
+        }
 
-                if(callChartLibraryUpdateSafely(data) === false)
-                    return;
-            }
-            else {
-                if(this.debug === true)
-                    this.log('creating chart...');
+        // string - the grouping method requested by the user
+        that.method = NETDATA.dataAttribute(that.element, 'method', NETDATA.chartDefaults.method);
+        that.gtime = NETDATA.dataAttribute(that.element, 'gtime', 0);
 
-                if(callChartLibraryCreateSafely(data) === false)
-                    return;
-            }
-            if(this.isVisible() === true) {
-                hideMessage();
-                this.legendShowLatestValues();
-            }
-            else {
-                this.__redraw_on_unhide = true;
+        // the time-range requested by the user
+        that.after = NETDATA.dataAttribute(that.element, 'after', NETDATA.chartDefaults.after);
+        that.before = NETDATA.dataAttribute(that.element, 'before', NETDATA.chartDefaults.before);
+
+        // the pixels per point requested by the user
+        that.pixels_per_point = NETDATA.dataAttribute(that.element, 'pixels-per-point', 1);
+        that.points = NETDATA.dataAttribute(that.element, 'points', null);
 
-                if(this.debug === true)
-                    this.log("drawn while not visible");
+        // the forced update_every
+        that.force_update_every = NETDATA.dataAttribute(that.element, 'update-every', null);
+        if (typeof that.force_update_every !== 'number' || that.force_update_every <= 1) {
+            if (that.force_update_every !== null) {
+                that.log('ignoring invalid value of property data-update-every');
             }
 
-            if(this.selected === true)
-                NETDATA.globalSelectionSync.stop();
+            that.force_update_every = null;
+        } else {
+            that.force_update_every *= 1000;
+        }
 
-            // update the performance counters
-            var now = Date.now();
-            this.tm.last_updated = now;
+        // the dimensions requested by the user
+        that.dimensions = NETDATA.encodeURIComponent(NETDATA.dataAttribute(that.element, 'dimensions', null));
 
-            // don't update last_autorefreshed if this chart is
-            // forced to be updated with global PanAndZoom
-            if(NETDATA.globalPanAndZoom.isActive())
-                this.tm.last_autorefreshed = 0;
-            else {
-                if(NETDATA.options.current.parallel_refresher === true && NETDATA.options.current.concurrent_refreshes === true && typeof this.force_update_every !== 'number')
-                    this.tm.last_autorefreshed = now - (now % this.data_update_every);
-                else
-                    this.tm.last_autorefreshed = now;
-            }
+        that.title = NETDATA.dataAttribute(that.element, 'title', null);    // the title of the chart
+        that.units = NETDATA.dataAttribute(that.element, 'units', null);    // the units of the chart dimensions
+        that.units_desired = NETDATA.dataAttribute(that.element, 'desired-units', NETDATA.options.current.units); // the units of the chart dimensions
+        that.units_current = that.units;
+        that.units_common = NETDATA.dataAttribute(that.element, 'common-units', null);
 
-            this.refresh_dt_ms = now - started;
-            NETDATA.options.auto_refresher_fast_weight += this.refresh_dt_ms;
+        // additional options to pass to netdata
+        that.append_options = NETDATA.encodeURIComponent(NETDATA.dataAttribute(that.element, 'append-options', null));
 
-            if(this.refresh_dt_element !== null)
-                this.refresh_dt_element.innerText = this.refresh_dt_ms.toString();
+        // override options to pass to netdata
+        that.override_options = NETDATA.encodeURIComponent(NETDATA.dataAttribute(that.element, 'override-options', null));
 
-            if(this.foreign_element_before !== null)
-                this.foreign_element_before.innerText = NETDATA.dateTime.localeDateString(this.view_before) + ' ' + NETDATA.dateTime.localeTimeString(this.view_before);
+        that.debug = NETDATA.dataAttributeBoolean(that.element, 'debug', false);
 
-            if(this.foreign_element_after !== null)
-                this.foreign_element_after.innerText = NETDATA.dateTime.localeDateString(this.view_after) + ' ' + NETDATA.dateTime.localeTimeString(this.view_after);
+        that.value_decimal_detail = -1;
+        let d = NETDATA.dataAttribute(that.element, 'decimal-digits', -1);
+        if (typeof d === 'number') {
+            that.value_decimal_detail = d;
+        } else if (typeof d !== 'undefined') {
+            that.log('ignoring decimal-digits value: ' + d.toString());
+        }
 
-            if(this.foreign_element_duration !== null)
-                this.foreign_element_duration.innerText = NETDATA.seconds4human(Math.floor((this.view_before - this.view_after) / 1000) + 1);
+        // if we need to report the rendering speed
+        // find the element that needs to be updated
+        let refresh_dt_element_name = NETDATA.dataAttribute(that.element, 'dt-element-name', null); // string - the element to print refresh_dt_ms
 
-            if(this.foreign_element_update_every !== null)
-                this.foreign_element_update_every.innerText = NETDATA.seconds4human(Math.floor(this.data_update_every / 1000));
+        if (refresh_dt_element_name !== null) {
+            that.refresh_dt_element = document.getElementById(refresh_dt_element_name) || null;
+        }
+        else {
+            that.refresh_dt_element = null;
+        }
+
+        that.dimensions_visibility = new dimensionsVisibility(that);
+
+        that.netdata_first = 0;                     // milliseconds - the first timestamp in netdata
+        that.netdata_last = 0;                      // milliseconds - the last timestamp in netdata
+        that.requested_after = null;                // milliseconds - the timestamp of the request after param
+        that.requested_before = null;               // milliseconds - the timestamp of the request before param
+        that.requested_padding = null;
+        that.view_after = 0;
+        that.view_before = 0;
+
+        that.refresh_dt_ms = 0;                     // milliseconds - the time the last refresh took
+
+        // how many retries we have made to load chart data from the server
+        that.retries_on_data_failures = 0;
+
+        // color management
+        that.colors = null;
+        that.colors_assigned = null;
+        that.colors_available = null;
+        that.colors_custom = null;
+
+        that.element_message = null; // the element already created by the user
+        that.element_chart = null; // the element with the chart
+        that.element_legend = null; // the element with the legend of the chart (if created by us)
+        that.element_legend_childs = {
+            content: null,
+            hidden: null,
+            title_date: null,
+            title_time: null,
+            title_units: null,
+            perfect_scroller: null, // the container to apply perfect scroller to
+            series: null
         };
 
-        this.getSnapshotData = function(key) {
-            if(this.debug === true)
-                this.log('updating from snapshot: ' + key);
+        that.chart_url = null;                      // string - the url to download chart info
+        that.chart = null;                          // object - the chart as downloaded from the server
 
-            if(typeof netdataSnapshotData.data[key] === 'undefined') {
-                this.log('snapshot does not include data for key "' + key + '"');
+        function get_foreign_element_by_id(opt) {
+            let id = NETDATA.dataAttribute(that.element, opt, null);
+            if (id === null) {
+                //that.log('option "' + opt + '" is undefined');
                 return null;
             }
 
-            if(typeof netdataSnapshotData.data[key] !== 'string') {
-                this.log('snapshot data for key "' + key + '" is not string');
+            let el = document.getElementById(id);
+            if (typeof el === 'undefined') {
+                that.log('cannot find an element with name "' + id.toString() + '"');
                 return null;
             }
 
-            var uncompressed;
-            try {
-                uncompressed = netdataSnapshotData.uncompress(netdataSnapshotData.data[key]);
-
-                if(uncompressed === null) {
-                    this.log('uncompressed snapshot data for key ' + key + ' is null');
-                    return null;
-                }
+            return el;
+        }
 
-                if(typeof uncompressed === 'undefined') {
-                    this.log('uncompressed snapshot data for key ' + key + ' is undefined');
-                    return null;
-                }
-            }
-            catch(e) {
-                this.log('decompression of snapshot data for key ' + key + ' failed');
-                console.log(e);
-                uncompressed = null;
-            }
+        that.foreign_element_before = get_foreign_element_by_id('show-before-at');
+        that.foreign_element_after = get_foreign_element_by_id('show-after-at');
+        that.foreign_element_duration = get_foreign_element_by_id('show-duration-at');
+        that.foreign_element_update_every = get_foreign_element_by_id('show-update-every-at');
+        that.foreign_element_selection = get_foreign_element_by_id('show-selection-at');
+    };
 
-            if(typeof uncompressed !== 'string') {
-                this.log('uncompressed snapshot data for key ' + key + ' is not string');
-                return null;
-            }
+    const destroyDOM = function () {
+        if (that.enabled === false) {
+            return;
+        }
 
-            var data;
-            try {
-                data = JSON.parse(uncompressed);
-            }
-            catch(e) {
-                this.log('parsing snapshot data for key ' + key + ' failed');
-                console.log(e);
-                data = null;
-            }
+        if (that.debug) {
+            that.log('destroyDOM()');
+        }
 
-            return data;
-        };
+        // that.element.className = 'netdata-message icon';
+        // that.element.innerHTML = '<i class="fas fa-sync"></i> netdata';
+        that.element.innerHTML = '';
+        that.element_message = null;
+        that.element_legend = null;
+        that.element_chart = null;
+        that.element_legend_childs.series = null;
 
-        this.updateChart = function(callback) {
-            if (this.debug === true)
-                this.log('updateChart()');
+        that.chart_created = false;
+        that.dom_created = false;
 
-            if (this.fetching_data === true) {
-                if (this.debug === true)
-                    this.log('updateChart(): I am already updating...');
+        that.tm.last_resized = 0;
+        that.tm.last_dom_created = 0;
+    };
 
-                if (typeof callback === 'function')
-                    return callback(false, 'already running');
+    let createDOM = function () {
+        if (that.enabled === false) {
+            return;
+        }
+        lateInitialization();
 
-                return;
-            }
+        destroyDOM();
 
-            // due to late initialization of charts and libraries
-            // we need to check this too
-            if (this.enabled === false) {
-                if (this.debug === true)
-                    this.log('updateChart(): I am not enabled');
+        if (that.debug) {
+            that.log('createDOM()');
+        }
 
-                if (typeof callback === 'function')
-                    return callback(false, 'not enabled');
+        that.element_message = document.createElement('div');
+        that.element_message.className = 'netdata-message icon hidden';
+        that.element.appendChild(that.element_message);
 
-                return;
-            }
+        that.dom_created = true;
+        that.chart_created = false;
 
-            if (canBeRendered() === false) {
-                if (this.debug === true)
-                    this.log('updateChart(): cannot be rendered');
+        that.tm.last_dom_created =
+            that.tm.last_resized = Date.now();
 
-                if (typeof callback === 'function')
-                    return callback(false, 'cannot be rendered');
+        showLoading();
+    };
 
-                return;
-            }
+    const initDOM = function () {
+        that.element.className = that.library.container_class(that);
 
-            if (that.dom_created !== true) {
-                if (this.debug === true)
-                    this.log('updateChart(): creating DOM');
+        if (typeof(that.width) === 'string') {
+            that.element.style.width = that.width;
+        } else if (typeof(that.width) === 'number') {
+            that.element.style.width = that.width.toString() + 'px';
+        }
 
-                createDOM();
+        if (typeof(that.library.aspect_ratio) === 'undefined') {
+            if (typeof(that.height) === 'string') {
+                that.element.style.height = that.height;
+            } else if (typeof(that.height) === 'number') {
+                that.element.style.height = that.height.toString() + 'px';
             }
+        }
 
-            if (this.chart === null) {
-                if (this.debug === true)
-                    this.log('updateChart(): getting chart');
+        if (NETDATA.chartDefaults.min_width !== null) {
+            that.element.style.min_width = NETDATA.chartDefaults.min_width;
+        }
+    };
 
-                return this.getChart(function () {
-                    return that.updateChart(callback);
-                });
-            }
+    const invisibleSearchableText = function () {
+        return '<span style="position:absolute; opacity: 0; width: 0px;">' + that.id + '</span>';
+    };
 
-            if(this.library.initialized === false) {
-                if(this.library.enabled === true) {
-                    if(this.debug === true)
-                        this.log('updateChart(): initializing chart library');
+    /* init() private
+     * initialize state variables
+     * destroy all (possibly) created state elements
+     * create the basic DOM for a chart
+     */
+    const init = function (opt) {
+        if (that.enabled === false) {
+            return;
+        }
 
-                    return this.library.initialize(function () {
-                        return that.updateChart(callback);
-                    });
-                }
-                else {
-                    error('chart library "' + this.library_name + '" is not available.');
+        runtimeInit();
+        that.element.innerHTML = invisibleSearchableText();
 
-                    if(typeof callback === 'function')
-                        return callback(false, 'library not available');
+        that.tm.last_initialized = Date.now();
+        that.setMode('auto');
 
-                    return;
-                }
+        if (opt !== 'fast') {
+            if (that.isVisible(true) || opt === 'force') {
+                createDOM();
             }
+        }
+    };
 
-            this.clearSelection();
-            this.chartURL();
+    const maxMessageFontSize = function () {
+        let screenHeight = screen.height;
+        let el = that.element;
 
-            NETDATA.statistics.refreshes_total++;
-            NETDATA.statistics.refreshes_active++;
+        // normally we want a font size, as tall as the element
+        let h = el.clientHeight;
 
-            if(NETDATA.statistics.refreshes_active > NETDATA.statistics.refreshes_active_max)
-                NETDATA.statistics.refreshes_active_max = NETDATA.statistics.refreshes_active;
+        // but give it some air, 20% let's say, or 5 pixels min
+        let lost = Math.max(h * 0.2, 5);
+        h -= lost;
 
-            var ok = false;
-            this.fetching_data = true;
+        // center the text, vertically
+        let paddingTop = (lost - 5) / 2;
 
-            if(netdataSnapshotData !== null) {
-                var key = this.chartDataUniqueID();
-                var data = this.getSnapshotData(key);
-                if (data !== null) {
-                    ok = true;
-                    data = NETDATA.xss.checkData('/api/v1/data', data, this.library.xssRegexIgnore);
-                    this.updateChartWithData(data);
-                }
-                else {
-                    ok = false;
-                    error('cannot get data from snapshot for key: "' + key + '"');
-                    that.tm.last_autorefreshed = Date.now();
-                }
+        // but check the width too
+        // it should fit 10 characters in it
+        let w = el.clientWidth / 10;
+        if (h > w) {
+            paddingTop += (h - w) / 2;
+            h = w;
+        }
 
-                NETDATA.statistics.refreshes_active--;
-                this.fetching_data = false;
+        // and don't make it too huge
+        // 5% of the screen size is good
+        if (h > screenHeight / 20) {
+            paddingTop += (h - (screenHeight / 20)) / 2;
+            h = screenHeight / 20;
+        }
 
-                if(typeof callback === 'function')
-                    callback(ok, 'snapshot');
+        // set it
+        that.element_message.style.fontSize = h.toString() + 'px';
+        that.element_message.style.paddingTop = paddingTop.toString() + 'px';
+    };
 
-                return;
-            }
+    const showMessageIcon = function (icon) {
+        that.element_message.innerHTML = icon;
+        maxMessageFontSize();
+        $(that.element_message).removeClass('hidden');
+        that.tmp.___messageHidden___ = undefined;
+    };
 
-            if(this.debug === true)
-                this.log('updating from ' + this.data_url);
+    const hideMessage = function () {
+        if (typeof that.tmp.___messageHidden___ === 'undefined') {
+            that.tmp.___messageHidden___ = true;
+            $(that.element_message).addClass('hidden');
+        }
+    };
 
-            this.xhr = $.ajax( {
-                url: this.data_url,
-                cache: false,
-                async: true,
-                headers: {
-                    'Cache-Control': 'no-cache, no-store',
-                    'Pragma': 'no-cache'
-                },
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function(data) {
-                data = NETDATA.xss.checkData('/api/v1/data', data, that.library.xssRegexIgnore);
+    const showRendering = function () {
+        let icon;
+        if (that.chart !== null) {
+            if (that.chart.chart_type === 'line') {
+                icon = NETDATA.icons.lineChart;
+            } else {
+                icon = NETDATA.icons.areaChart;
+            }
+        }
+        else {
+            icon = NETDATA.icons.noChart;
+        }
 
-                that.xhr = undefined;
-                that.retries_on_data_failures = 0;
-                ok = true;
+        showMessageIcon(icon + ' netdata' + invisibleSearchableText());
+    };
 
-                if(that.debug === true)
-                    that.log('data received. updating chart.');
+    const showLoading = function () {
+        if (that.chart_created === false) {
+            showMessageIcon(NETDATA.icons.loading + ' netdata');
+            return true;
+        }
+        return false;
+    };
 
-                that.updateChartWithData(data);
-            })
-            .fail(function(msg) {
-                that.xhr = undefined;
+    const isHidden = function () {
+        return (typeof that.tmp.___chartIsHidden___ !== 'undefined');
+    };
 
-                if(msg.statusText !== 'abort') {
-                    that.retries_on_data_failures++;
-                    if(that.retries_on_data_failures > NETDATA.options.current.retries_on_data_failures) {
-                        // that.log('failed ' + that.retries_on_data_failures.toString() + ' times - giving up');
-                        that.retries_on_data_failures = 0;
-                        error('data download failed for url: ' + that.data_url);
-                    }
-                    else {
-                        that.tm.last_autorefreshed = Date.now();
-                        // that.log('failed ' + that.retries_on_data_failures.toString() + ' times, but I will retry');
+    // hide the chart, when it is not visible - called from isVisible()
+    this.hideChart = function () {
+        // hide it, if it is not already hidden
+        // if (isHidden() === true) return;
+        if (isHidden()) {
+            return;
+        }
+
+        if (this.chart_created) {
+            if (NETDATA.options.current.show_help) {
+                if (this.element_legend_childs.toolbox !== null) {
+                    if (this.debug) {
+                        this.log('hideChart(): hidding legend popovers');
                     }
+
+                    $(this.element_legend_childs.toolbox_left).popover('hide');
+                    $(this.element_legend_childs.toolbox_reset).popover('hide');
+                    $(this.element_legend_childs.toolbox_right).popover('hide');
+                    $(this.element_legend_childs.toolbox_zoomin).popover('hide');
+                    $(this.element_legend_childs.toolbox_zoomout).popover('hide');
                 }
-            })
-            .always(function() {
-                that.xhr = undefined;
 
-                NETDATA.statistics.refreshes_active--;
-                that.fetching_data = false;
+                if (this.element_legend_childs.resize_handler !== null) {
+                    $(this.element_legend_childs.resize_handler).popover('hide');
+                }
 
-                if(typeof callback === 'function')
-                    return callback(ok, 'download');
-            });
-        };
+                if (this.element_legend_childs.content !== null) {
+                    $(this.element_legend_childs.content).popover('hide');
+                }
+            }
 
-        var __isVisible = function() {
-            var ret = true;
+            if (NETDATA.options.current.destroy_on_hide) {
+                if (this.debug) {
+                    this.log('hideChart(): initializing chart');
+                }
+
+                // we should destroy it
+                init('force');
+            } else {
+                if (this.debug) {
+                    this.log('hideChart(): hiding chart');
+                }
+
+                showRendering();
+                this.element_chart.style.display = 'none';
+                this.element.style.willChange = 'auto';
+                if (this.element_legend !== null) {
+                    this.element_legend.style.display = 'none';
+                }
+                if (this.element_legend_childs.toolbox !== null) {
+                    this.element_legend_childs.toolbox.style.display = 'none';
+                }
+                if (this.element_legend_childs.resize_handler !== null) {
+                    this.element_legend_childs.resize_handler.style.display = 'none';
+                }
 
-            if(NETDATA.options.current.update_only_visible !== false) {
-                // tolerance is the number of pixels a chart can be off-screen
-                // to consider it as visible and refresh it as if was visible
-                var tolerance = 0;
+                this.tm.last_hidden = Date.now();
 
-                that.tm.last_visible_check = Date.now();
+                // de-allocate data
+                // This works, but I not sure there are no corner cases somewhere
+                // so it is commented - if the user has memory issues he can
+                // set Destroy on Hide for all charts
+                // this.data = null;
+            }
+        }
 
-                var rect = that.element.getBoundingClientRect();
+        this.tmp.___chartIsHidden___ = true;
+    };
 
-                var screenTop = window.scrollY;
-                var screenBottom = screenTop + window.innerHeight;
+    // unhide the chart, when it is visible - called from isVisible()
+    this.unhideChart = function () {
+        if (isHidden() === false) {
+            return;
+        }
 
-                var chartTop = rect.top + screenTop;
-                var chartBottom = chartTop + rect.height;
+        this.tmp.___chartIsHidden___ = undefined;
+        this.updates_since_last_unhide = 0;
 
-                ret = !(rect.width === 0 || rect.height === 0 || chartBottom + tolerance < screenTop || chartTop - tolerance > screenBottom);
+        if (this.chart_created === false) {
+            if (this.debug) {
+                this.log('unhideChart(): initializing chart');
             }
 
-            if(that.debug === true)
-                that.log('__isVisible(): ' + ret);
-
-            return ret;
-        };
+            // we need to re-initialize it, to show our background
+            // logo in bootstrap tabs, until the chart loads
+            init('force');
+        } else {
+            if (this.debug) {
+                this.log('unhideChart(): unhiding chart');
+            }
 
-        this.isVisible = function(nocache) {
-            // this.log('last_visible_check: ' + this.tm.last_visible_check + ', last_page_scroll: ' + NETDATA.options.last_page_scroll);
+            this.element.style.willChange = 'transform';
+            this.tm.last_unhidden = Date.now();
+            this.element_chart.style.display = '';
+            if (this.element_legend !== null) {
+                this.element_legend.style.display = '';
+            }
+            if (this.element_legend_childs.toolbox !== null) {
+                this.element_legend_childs.toolbox.style.display = '';
+            }
+            if (this.element_legend_childs.resize_handler !== null) {
+                this.element_legend_childs.resize_handler.style.display = '';
+            }
+            resizeChart();
+            hideMessage();
+        }
 
-            // caching - we do not evaluate the charts visibility
-            // if the page has not been scrolled since the last check
-            if((typeof nocache !== 'undefined' && nocache === true)
-                || typeof this.tmp.___isVisible___ === 'undefined'
-                || this.tm.last_visible_check <= NETDATA.options.last_page_scroll) {
-                this.tmp.___isVisible___ = __isVisible();
-                if (this.tmp.___isVisible___ === true) this.unhideChart();
-                else this.hideChart();
+        if (this.__redraw_on_unhide) {
+            if (this.debug) {
+                this.log("redrawing chart on unhide");
             }
 
-            if(this.debug === true)
-                this.log('isVisible(' + nocache + '): ' + this.tmp.___isVisible___);
+            this.__redraw_on_unhide = undefined;
+            this.redrawChart();
+        }
+    };
 
-            return this.tmp.___isVisible___;
-        };
+    const canBeRendered = function (uncached_visibility) {
+        if (that.debug) {
+            that.log('canBeRendered() called');
+        }
 
-        this.isAutoRefreshable = function() {
-            return (this.current.autorefresh);
-        };
+        // if (NETDATA.options.current.update_only_visible === false)
+        if (!NETDATA.options.current.update_only_visible) {
+            return true;
+        }
 
-        this.canBeAutoRefreshed = function() {
-            if(this.enabled === false) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> not enabled');
+        let ret = (
+            (
+                NETDATA.options.page_is_visible ||
+                NETDATA.options.current.stop_updates_when_focus_is_lost === false ||
+                that.updates_since_last_unhide === 0
+            )
+            && isHidden() === false && that.isVisible(uncached_visibility)
+        );
 
-                return false;
-            }
+        if (that.debug) {
+            that.log('canBeRendered(): ' + ret);
+        }
 
-            if(this.running === true) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> already running');
+        return ret;
+    };
 
-                return false;
-            }
+    // https://github.com/petkaantonov/bluebird/wiki/Optimization-killers
+    const callChartLibraryUpdateSafely = function (data) {
+        let status;
 
-            if(this.library === null || this.library.enabled === false) {
-                error('charting library "' + this.library_name + '" is not available');
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> chart library ' + this.library_name + ' is not available');
+        // we should not do this here
+        // if we prevent rendering the chart then:
+        // 1. globalSelectionSync will be wrong
+        // 2. globalPanAndZoom will be wrong
+        //if (canBeRendered(true) === false)
+        //    return false;
 
-                return false;
-            }
+        if (NETDATA.options.fake_chart_rendering) {
+            return true;
+        }
 
-            if(this.isVisible() === false) {
-                if(NETDATA.options.debug.visibility === true || this.debug === true)
-                    this.log('canBeAutoRefreshed() -> not visible');
+        that.updates_counter++;
+        that.updates_since_last_unhide++;
+        that.updates_since_last_creation++;
 
-                return false;
+        if (NETDATA.options.debug.chart_errors) {
+            status = that.library.update(that, data);
+        } else {
+            try {
+                status = that.library.update(that, data);
+            } catch (err) {
+                status = false;
             }
+        }
 
-            var now = Date.now();
+        if (!status) {
+            error('chart failed to be updated as ' + that.library_name);
+            return false;
+        }
 
-            if(this.current.force_update_at !== 0 && this.current.force_update_at < now) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> timed force update - allowing this update');
+        return true;
+    };
 
-                this.current.force_update_at = 0;
-                return true;
-            }
+    // https://github.com/petkaantonov/bluebird/wiki/Optimization-killers
+    const callChartLibraryCreateSafely = function (data) {
+        let status;
 
-            if(this.isAutoRefreshable() === false) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> not auto-refreshable');
+        // we should not do this here
+        // if we prevent rendering the chart then:
+        // 1. globalSelectionSync will be wrong
+        // 2. globalPanAndZoom will be wrong
+        //if (canBeRendered(true) === false)
+        //    return false;
 
-                return false;
-            }
+        if (NETDATA.options.fake_chart_rendering) {
+            return true;
+        }
 
-            // allow the first update, even if the page is not visible
-            if(NETDATA.options.page_is_visible === false && this.updates_counter && this.updates_since_last_unhide) {
-                if(NETDATA.options.debug.focus === true || this.debug === true)
-                    this.log('canBeAutoRefreshed() -> not the first update, and page does not have focus');
+        that.updates_counter++;
+        that.updates_since_last_unhide++;
+        that.updates_since_last_creation++;
 
-                return false;
+        if (NETDATA.options.debug.chart_errors) {
+            status = that.library.create(that, data);
+        } else {
+            try {
+                status = that.library.create(that, data);
+            } catch (err) {
+                status = false;
             }
+        }
 
-            if(this.needsRecreation() === true) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> needs re-creation.');
-
-                return true;
-            }
+        if (!status) {
+            error('chart failed to be created as ' + that.library_name);
+            return false;
+        }
 
-            if(NETDATA.options.auto_refresher_stop_until >= now) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed() -> stopped until is in future.');
+        that.chart_created = true;
+        that.updates_since_last_creation = 0;
+        return true;
+    };
 
-                return false;
+    // ----------------------------------------------------------------------------------------------------------------
+    // Chart Resize
+
+    // resizeChart() - private
+    // to be called just before the chart library to make sure that
+    // a properly sized dom is available
+    const resizeChart = function () {
+        if (that.tm.last_resized < NETDATA.options.last_page_resize) {
+            if (!that.chart_created) {
+                return;
             }
 
-            // options valid only for autoRefresh()
-            if(NETDATA.globalPanAndZoom.isActive()) {
-                if(NETDATA.globalPanAndZoom.shouldBeAutoRefreshed(this)) {
-                    if(this.debug === true)
-                        this.log('canBeAutoRefreshed(): global panning: I need an update.');
+            if (that.needsRecreation()) {
+                if (that.debug) {
+                    that.log('resizeChart(): initializing chart');
+                }
 
-                    return true;
+                init('force');
+            } else if (typeof that.library.resize === 'function') {
+                if (that.debug) {
+                    that.log('resizeChart(): resizing chart');
                 }
-                else {
-                    if(this.debug === true)
-                        this.log('canBeAutoRefreshed(): global panning: I am already up to date.');
 
-                    return false;
+                that.library.resize(that);
+
+                if (that.element_legend_childs.perfect_scroller !== null) {
+                    Ps.update(that.element_legend_childs.perfect_scroller);
                 }
+
+                maxMessageFontSize();
             }
 
-            if(this.selected === true) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed(): I have a selection in place.');
+            that.tm.last_resized = Date.now();
+        }
+    };
 
-                return false;
-            }
+    // this is the actual chart resize algorithm
+    // it will:
+    // - resize the entire container
+    // - update the internal states
+    // - resize the chart as the div changes height
+    // - update the scrollbar of the legend
+    const resizeChartToHeight = function (h) {
+        // console.log(h);
+        that.element.style.height = h;
 
-            if(this.paused === true) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed(): I am paused.');
+        if (that.settings_id !== null) {
+            NETDATA.localStorageSet('chart_heights.' + that.settings_id, h);
+        }
 
-                return false;
-            }
+        let now = Date.now();
+        NETDATA.options.last_page_scroll = now;
+        NETDATA.options.auto_refresher_stop_until = now + NETDATA.options.current.stop_updates_while_resizing;
 
-            var data_update_every = this.data_update_every;
-            if(typeof this.force_update_every === 'number')
-                data_update_every = this.force_update_every;
+        // force a resize
+        that.tm.last_resized = 0;
+        resizeChart();
+    };
 
-            if(now - this.tm.last_autorefreshed >= data_update_every) {
-                if(this.debug === true)
-                    this.log('canBeAutoRefreshed(): It is time to update me. Now: ' + now.toString() + ', last_autorefreshed: ' + this.tm.last_autorefreshed + ', data_update_every: ' + data_update_every + ', delta: ' + (now - this.tm.last_autorefreshed).toString());
+    this.resizeForPrint = function () {
+        if (typeof this.element_legend_childs !== 'undefined' && this.element_legend_childs.perfect_scroller !== null) {
+            let current = this.element.clientHeight;
+            let optimal = current
+                + this.element_legend_childs.perfect_scroller.scrollHeight
+                - this.element_legend_childs.perfect_scroller.clientHeight;
 
-                return true;
+            if (optimal > current) {
+                // this.log('resized');
+                this.element.style.height = optimal + 'px';
+                this.library.resize(this);
             }
+        }
+    };
 
-            return false;
-        };
+    this.resizeHandler = function (e) {
+        e.preventDefault();
 
-        this.autoRefresh = function(callback) {
-            var state = that;
+        if (typeof this.event_resize === 'undefined'
+            || this.event_resize.chart_original_w === 'undefined'
+            || this.event_resize.chart_original_h === 'undefined') {
+            this.event_resize = {
+                chart_original_w: this.element.clientWidth,
+                chart_original_h: this.element.clientHeight,
+                last: 0
+            };
+        }
 
-            if(state.canBeAutoRefreshed() === true && state.running === false) {
+        if (e.type === 'touchstart') {
+            this.event_resize.mouse_start_x = e.touches.item(0).pageX;
+            this.event_resize.mouse_start_y = e.touches.item(0).pageY;
+        } else {
+            this.event_resize.mouse_start_x = e.clientX;
+            this.event_resize.mouse_start_y = e.clientY;
+        }
 
-                state.running = true;
-                state.updateChart(function() {
-                    state.running = false;
+        this.event_resize.chart_start_w = this.element.clientWidth;
+        this.event_resize.chart_start_h = this.element.clientHeight;
+        this.event_resize.chart_last_w = this.element.clientWidth;
+        this.event_resize.chart_last_h = this.element.clientHeight;
 
-                    if(typeof callback === 'function')
-                        return callback();
-                });
-            }
-            else {
-                if(typeof callback === 'function')
-                    return callback();
-            }
-        };
+        let now = Date.now();
+        if (now - this.event_resize.last <= NETDATA.options.current.double_click_speed && this.element_legend_childs.perfect_scroller !== null) {
+            // double click / double tap event
 
-        this.__defaultsFromDownloadedChart = function(chart) {
-            this.chart = chart;
-            this.chart_url = chart.url;
-            this.data_update_every = chart.update_every * 1000;
-            this.data_points = Math.round(this.chartWidth() / this.chartPixelsPerPoint());
-            this.tm.last_info_downloaded = Date.now();
+            // console.dir(this.element_legend_childs.content);
+            // console.dir(this.element_legend_childs.perfect_scroller);
 
-            if(this.title === null)
-                this.title = chart.title;
+            // the optimal height of the chart
+            // showing the entire legend
+            let optimal = this.event_resize.chart_last_h
+                + this.element_legend_childs.perfect_scroller.scrollHeight
+                - this.element_legend_childs.perfect_scroller.clientHeight;
 
-            if(this.units === null) {
-                this.units = chart.units;
-                this.units_current = this.units;
+            // if we are not optimal, be optimal
+            if (this.event_resize.chart_last_h !== optimal) {
+                // this.log('resize to optimal, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString());
+                resizeChartToHeight(optimal.toString() + 'px');
             }
-        };
 
-        // fetch the chart description from the netdata server
-        this.getChart = function(callback) {
-            this.chart = NETDATA.chartRegistry.get(this.host, this.id);
-            if(this.chart) {
-                this.__defaultsFromDownloadedChart(this.chart);
-
-                if(typeof callback === 'function')
-                    return callback();
+            // else if the current height is not the original/saved height
+            // reset to the original/saved height
+            else if (this.event_resize.chart_last_h !== this.event_resize.chart_original_h) {
+                // this.log('resize to original, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString());
+                resizeChartToHeight(this.event_resize.chart_original_h.toString() + 'px');
             }
-            else if(netdataSnapshotData !== null) {
-                // console.log(this);
-                // console.log(NETDATA.chartRegistry);
-                NETDATA.error(404, 'host: ' + this.host + ', chart: ' +  this.id);
-                error('chart not found in snapshot');
 
-                if(typeof callback === 'function')
-                    return callback();
+            // else if the current height is not the internal default height
+            // reset to the internal default height
+            else if ((this.event_resize.chart_last_h.toString() + 'px') !== this.height_original) {
+                // this.log('resize to internal default, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString());
+                resizeChartToHeight(this.height_original.toString());
             }
-            else {
-                this.chart_url = "/api/v1/chart?chart=" + this.id;
 
-                if(this.debug === true)
-                    this.log('downloading ' + this.chart_url);
+            // else if the current height is not the firstchild's clientheight
+            // resize to it
+            else if (typeof this.element_legend_childs.perfect_scroller.firstChild !== 'undefined') {
+                let parent_rect = this.element.getBoundingClientRect();
+                let content_rect = this.element_legend_childs.perfect_scroller.firstElementChild.getBoundingClientRect();
+                let wanted = content_rect.top - parent_rect.top + this.element_legend_childs.perfect_scroller.firstChild.clientHeight + 18; // 15 = toolbox + 3 space
 
-                $.ajax( {
-                    url:  this.host + this.chart_url,
-                    cache: false,
-                    async: true,
-                    xhrFields: { withCredentials: true } // required for the cookie
-                })
-                .done(function(chart) {
-                    chart = NETDATA.xss.checkOptional('/api/v1/chart', chart);
+                // console.log(parent_rect);
+                // console.log(content_rect);
+                // console.log(wanted);
 
-                    chart.url = that.chart_url;
-                    that.__defaultsFromDownloadedChart(chart);
-                    NETDATA.chartRegistry.add(that.host, that.id, chart);
-                })
-                .fail(function() {
-                    NETDATA.error(404, that.chart_url);
-                    error('chart not found on url "' + that.chart_url + '"');
-                })
-                .always(function() {
-                    if(typeof callback === 'function')
-                        return callback();
-                });
+                // this.log('resize to firstChild, current = ' + this.event_resize.chart_last_h.toString() + 'px, original = ' + this.event_resize.chart_original_h.toString() + 'px, optimal = ' + optimal.toString() + 'px, internal = ' + this.height_original.toString() + 'px, firstChild = ' + wanted.toString() + 'px' );
+                if (this.event_resize.chart_last_h !== wanted) {
+                    resizeChartToHeight(wanted.toString() + 'px');
+                }
             }
-        };
-
-        // ============================================================================================================
-        // INITIALIZATION
+        } else {
+            this.event_resize.last = now;
 
-        initDOM();
-        init('fast');
-    };
+            // process movement event
+            document.onmousemove =
+                document.ontouchmove =
+                    this.element_legend_childs.resize_handler.onmousemove =
+                        this.element_legend_childs.resize_handler.ontouchmove =
+                            function (e) {
+                                let y = null;
+
+                                switch (e.type) {
+                                    case 'mousemove':
+                                        y = e.clientY;
+                                        break;
+                                    case 'touchmove':
+                                        y = e.touches.item(e.touches - 1).pageY;
+                                        break;
+                                }
 
-    NETDATA.resetAllCharts = function(state) {
-        // first clear the global selection sync
-        // to make sure no chart is in selected state
-        NETDATA.globalSelectionSync.stop();
-
-        // there are 2 possibilities here
-        // a. state is the global Pan and Zoom master
-        // b. state is not the global Pan and Zoom master
-        var master = true;
-        if(NETDATA.globalPanAndZoom.isMaster(state) === false)
-            master = false;
-
-        // clear the global Pan and Zoom
-        // this will also refresh the master
-        // and unblock any charts currently mirroring the master
-        NETDATA.globalPanAndZoom.clearMaster();
-
-        // if we were not the master, reset our status too
-        // this is required because most probably the mouse
-        // is over this chart, blocking it from auto-refreshing
-        if(master === false && (state.paused === true || state.selected === true))
-            state.resetChart();
-    };
+                                if (y !== null) {
+                                    let newH = that.event_resize.chart_start_h + y - that.event_resize.mouse_start_y;
 
-    // get or create a chart state, given a DOM element
-    NETDATA.chartState = function(element) {
-        var self = $(element);
+                                    if (newH >= 70 && newH !== that.event_resize.chart_last_h) {
+                                        resizeChartToHeight(newH.toString() + 'px');
+                                        that.event_resize.chart_last_h = newH;
+                                    }
+                                }
+                            };
 
-        var state = self.data('netdata-state-object') || null;
-        if(state === null) {
-            state = new chartState(element);
-            self.data('netdata-state-object', state);
-        }
-        return state;
-    };
+            // process end event
+            document.onmouseup =
+                document.ontouchend =
+                    this.element_legend_childs.resize_handler.onmouseup =
+                        this.element_legend_childs.resize_handler.ontouchend =
+                            function (e) {
+                                void(e);
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Library functions
-
-    // Load a script without jquery
-    // This is used to load jquery - after it is loaded, we use jquery
-    NETDATA._loadjQuery = function(callback) {
-        if(typeof jQuery === 'undefined') {
-            if(NETDATA.options.debug.main_loop === true)
-                console.log('loading ' + NETDATA.jQuery);
-
-            var script = document.createElement('script');
-            script.type = 'text/javascript';
-            script.async = true;
-            script.src = NETDATA.jQuery;
-
-            // script.onabort = onError;
-            script.onerror = function() { NETDATA.error(101, NETDATA.jQuery); };
-            if(typeof callback === "function") {
-                script.onload = function () {
-                    $ = jQuery;
-                    return callback();
-                };
-            }
+                                // remove all the hooks
+                                document.onmouseup =
+                                    document.onmousemove =
+                                        document.ontouchmove =
+                                            document.ontouchend =
+                                                that.element_legend_childs.resize_handler.onmousemove =
+                                                    that.element_legend_childs.resize_handler.ontouchmove =
+                                                        that.element_legend_childs.resize_handler.onmouseout =
+                                                            that.element_legend_childs.resize_handler.onmouseup =
+                                                                that.element_legend_childs.resize_handler.ontouchend =
+                                                                    null;
 
-            var s = document.getElementsByTagName('script')[0];
-            s.parentNode.insertBefore(script, s);
-        }
-        else if(typeof callback === "function") {
-            $ = jQuery;
-            return callback();
+                                // allow auto-refreshes
+                                NETDATA.options.auto_refresher_stop_until = 0;
+                            };
         }
     };
 
-    NETDATA._loadCSS = function(filename) {
-        // don't use jQuery here
-        // styles are loaded before jQuery
-        // to eliminate showing an unstyled page to the user
-
-        var fileref = document.createElement("link");
-        fileref.setAttribute("rel", "stylesheet");
-        fileref.setAttribute("type", "text/css");
-        fileref.setAttribute("href", filename);
-
-        if (typeof fileref !== 'undefined')
-            document.getElementsByTagName("head")[0].appendChild(fileref);
+    const noDataToShow = function () {
+        showMessageIcon(NETDATA.icons.noData + ' empty');
+        that.legendUpdateDOM();
+        that.tm.last_autorefreshed = Date.now();
+        // that.data_update_every = 30 * 1000;
+        //that.element_chart.style.display = 'none';
+        //if (that.element_legend !== null) that.element_legend.style.display = 'none';
+        //that.tmp.___chartIsHidden___ = true;
     };
 
-    NETDATA.colorHex2Rgb = function(hex) {
-        // Expand shorthand form (e.g. "03F") to full form (e.g. "0033FF")
-        var shorthandRegex = /^#?([a-f\d])([a-f\d])([a-f\d])$/i;
-            hex = hex.replace(shorthandRegex, function(m, r, g, b) {
-            return r + r + g + g + b + b;
-        });
+    // ============================================================================================================
+    // PUBLIC FUNCTIONS
 
-        var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
-        return result ? {
-            r: parseInt(result[1], 16),
-            g: parseInt(result[2], 16),
-            b: parseInt(result[3], 16)
-        } : null;
+    this.error = function (msg) {
+        error(msg);
     };
 
-    NETDATA.colorLuminance = function(hex, lum) {
-        // validate hex string
-        hex = String(hex).replace(/[^0-9a-f]/gi, '');
-        if (hex.length < 6)
-            hex = hex[0]+hex[0]+hex[1]+hex[1]+hex[2]+hex[2];
-
-        lum = lum || 0;
-
-        // convert to decimal and change luminosity
-        var rgb = "#", c, i;
-        for (i = 0; i < 3; i++) {
-            c = parseInt(hex.substr(i*2,2), 16);
-            c = Math.round(Math.min(Math.max(0, c + (c * lum)), 255)).toString(16);
-            rgb += ("00"+c).substr(c.length);
+    this.setMode = function (m) {
+        if (this.current !== null && this.current.name === m) {
+            return;
         }
 
-        return rgb;
-    };
+        if (m === 'auto') {
+            this.current = this.auto;
+        } else if (m === 'pan') {
+            this.current = this.pan;
+        } else if (m === 'zoom') {
+            this.current = this.zoom;
+        } else {
+            this.current = this.auto;
+        }
 
-    NETDATA.guid = function() {
-        function s4() {
-            return Math.floor((1 + Math.random()) * 0x10000)
-                    .toString(16)
-                    .substring(1);
-            }
+        this.current.force_update_at = 0;
+        this.current.force_before_ms = null;
+        this.current.force_after_ms = null;
 
-            return s4() + s4() + '-' + s4() + '-' + s4() + '-' + s4() + '-' + s4() + s4() + s4();
+        this.tm.last_mode_switch = Date.now();
     };
 
-    NETDATA.zeropad = function(x) {
-        if(x > -10 && x < 10) return '0' + x.toString();
-        else return x.toString();
+    // ----------------------------------------------------------------------------------------------------------------
+    // global selection sync for slaves
+
+    // can the chart participate to the global selection sync as a slave?
+    this.globalSelectionSyncIsEligible = function () {
+        return (
+            this.enabled &&
+            this.library !== null &&
+            typeof this.library.setSelection === 'function' &&
+            this.isVisible() &&
+            this.chart_created
+        );
     };
 
-    // user function to signal us the DOM has been
-    // updated.
-    NETDATA.updatedDom = function() {
-        NETDATA.options.updated_dom = true;
-    };
+    this.setSelection = function (t) {
+        if (typeof this.library.setSelection === 'function') {
+            // this.selected = this.library.setSelection(this, t) === true;
+            this.selected = this.library.setSelection(this, t);
+        } else {
+            this.selected = true;
+        }
 
-    NETDATA.ready = function(callback) {
-        NETDATA.options.pauseCallback = callback;
-    };
+        if (this.selected && this.debug) {
+            this.log('selection set to ' + t.toString());
+        }
 
-    NETDATA.pause = function(callback) {
-        if(typeof callback === 'function') {
-            if (NETDATA.options.pause === true)
-                return callback();
-            else
-                NETDATA.options.pauseCallback = callback;
+        if (this.foreign_element_selection !== null) {
+            this.foreign_element_selection.innerText = NETDATA.dateTime.localeDateString(t) + ' ' + NETDATA.dateTime.localeTimeString(t);
         }
-    };
 
-    NETDATA.unpause = function() {
-        NETDATA.options.pauseCallback = null;
-        NETDATA.options.updated_dom = true;
-        NETDATA.options.pause = false;
+        return this.selected;
     };
 
-    NETDATA.seconds4human = function (seconds, options) {
-        var default_options = {
-            now: 'now',
-            space: ' ',
-            negative_suffix: 'ago',
-            day: 'day',
-            days: 'days',
-            hour: 'hour',
-            hours: 'hours',
-            minute: 'min',
-            minutes: 'mins',
-            second: 'sec',
-            seconds: 'secs',
-            and: 'and'
-        };
-
-        if(typeof options !== 'object')
-            options = default_options;
-        else {
-            var x;
-            for(x in default_options) {
-                if(typeof options[x] !== 'string')
-                    options[x] = default_options[x];
+    this.clearSelection = function () {
+        if (this.selected) {
+            if (typeof this.library.clearSelection === 'function') {
+                this.selected = (this.library.clearSelection(this) !== true);
+            } else {
+                this.selected = false;
             }
-        }
 
-        if(typeof seconds === 'string')
-            seconds = parseInt(seconds, 10);
+            if (this.selected === false && this.debug) {
+                this.log('selection cleared');
+            }
 
-        if(seconds === 0)
-            return options.now;
+            if (this.foreign_element_selection !== null) {
+                this.foreign_element_selection.innerText = '';
+            }
 
-        var suffix = '';
-        if(seconds < 0) {
-            seconds = -seconds;
-            if(options.negative_suffix !== '') suffix = options.space + options.negative_suffix;
+            this.legendReset();
         }
 
-        var days = Math.floor(seconds / 86400);
-        seconds -= (days * 86400);
-
-        var hours = Math.floor(seconds / 3600);
-        seconds -= (hours * 3600);
-
-        var minutes = Math.floor(seconds / 60);
-        seconds -= (minutes * 60);
-
-        var strings = [];
-
-        if(days > 1) strings.push(days.toString() + options.space + options.days);
-        else if(days === 1) strings.push(days.toString() + options.space + options.day);
-
-        if(hours > 1) strings.push(hours.toString() + options.space + options.hours);
-        else if(hours === 1) strings.push(hours.toString() + options.space + options.hour);
-
-        if(minutes > 1) strings.push(minutes.toString() + options.space + options.minutes);
-        else if(minutes === 1) strings.push(minutes.toString() + options.space + options.minute);
-
-        if(seconds > 1) strings.push(Math.floor(seconds).toString() + options.space + options.seconds);
-        else if(seconds === 1) strings.push(Math.floor(seconds).toString() + options.space + options.second);
-
-        if(strings.length === 1)
-            return strings.pop() + suffix;
-
-        var last = strings.pop();
-        return strings.join(", ") + " " + options.and + " " + last + suffix;
+        return this.selected;
     };
 
     // ----------------------------------------------------------------------------------------------------------------
 
-    // this is purely sequential charts refresher
-    // it is meant to be autonomous
-    NETDATA.chartRefresherNoParallel = function(index, callback) {
-        var targets = NETDATA.intersectionObserver.targets();
-
-        if(NETDATA.options.debug.main_loop === true)
-            console.log('NETDATA.chartRefresherNoParallel(' + index + ')');
-
-        if(NETDATA.options.updated_dom === true) {
-            // the dom has been updated
-            // get the dom parts again
-            NETDATA.parseDom(callback);
-            return;
-        }
-        if(index >= targets.length) {
-            if(NETDATA.options.debug.main_loop === true)
-                console.log('waiting to restart main loop...');
+    // find if a timestamp (ms) is shown in the current chart
+    this.timeIsVisible = function (t) {
+        return (t >= this.data_after && t <= this.data_before);
+    };
 
-            NETDATA.options.auto_refresher_fast_weight = 0;
-            callback();
+    this.calculateRowForTime = function (t) {
+        if (this.timeIsVisible(t) === false) {
+            return -1;
         }
-        else {
-            var state = targets[index];
+        return Math.floor((t - this.data_after) / this.data_update_every);
+    };
 
-            if(NETDATA.options.auto_refresher_fast_weight < NETDATA.options.current.fast_render_timeframe) {
-                if(NETDATA.options.debug.main_loop === true)
-                    console.log('fast rendering...');
+    // ----------------------------------------------------------------------------------------------------------------
 
-                if(state.isVisible() === true)
-                    NETDATA.timeout.set(function() {
-                        state.autoRefresh(function () {
-                            NETDATA.chartRefresherNoParallel(++index, callback);
-                        });
-                    }, 0);
-                else
-                    NETDATA.chartRefresherNoParallel(++index, callback);
+    this.pauseChart = function () {
+        if (this.paused === false) {
+            if (this.debug) {
+                this.log('pauseChart()');
             }
-            else {
-                if(NETDATA.options.debug.main_loop === true) console.log('waiting for next refresh...');
-                NETDATA.options.auto_refresher_fast_weight = 0;
 
-                NETDATA.timeout.set(function() {
-                    state.autoRefresh(function() {
-                        NETDATA.chartRefresherNoParallel(++index, callback);
-                    });
-                }, NETDATA.options.current.idle_between_charts);
-            }
+            this.paused = true;
         }
     };
 
-    NETDATA.chartRefresherWaitTime = function() {
-        return NETDATA.options.current.idle_parallel_loops;
-    };
-
-    // the default refresher
-    NETDATA.chartRefresherLastRun = 0;
-    NETDATA.chartRefresherRunsAfterParseDom = 0;
-    NETDATA.chartRefresherTimeoutId = undefined;
+    this.unpauseChart = function () {
+        if (this.paused) {
+            if (this.debug) {
+                this.log('unpauseChart()');
+            }
 
-    NETDATA.chartRefresherReschedule = function() {
-        if(NETDATA.options.current.async_on_scroll === true) {
-            if(NETDATA.chartRefresherTimeoutId)
-                NETDATA.timeout.clear(NETDATA.chartRefresherTimeoutId);
-            NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(NETDATA.chartRefresher, NETDATA.options.current.onscroll_worker_duration_threshold);
-            //console.log('chartRefresherReschedule()');
+            this.paused = false;
         }
     };
 
-    NETDATA.chartRefresher = function() {
-        // console.log('chartRefresher() begin ' + (Date.now() - NETDATA.chartRefresherLastRun).toString() + ' ms since last run');
-
-        if(NETDATA.options.page_is_visible === false
-            && NETDATA.options.current.stop_updates_when_focus_is_lost === true
-            && NETDATA.chartRefresherLastRun > NETDATA.options.last_page_resize
-            && NETDATA.chartRefresherLastRun > NETDATA.options.last_page_scroll
-            && NETDATA.chartRefresherRunsAfterParseDom > 10
-        ) {
-            setTimeout(
-                NETDATA.chartRefresher,
-                NETDATA.options.current.idle_lost_focus
-            );
-
-            // console.log('chartRefresher() page without focus, will run in ' + NETDATA.options.current.idle_lost_focus.toString() + ' ms, ' + NETDATA.chartRefresherRunsAfterParseDom.toString());
-            return;
+    this.resetChart = function (dont_clear_master, dont_update) {
+        if (this.debug) {
+            this.log('resetChart(' + dont_clear_master + ', ' + dont_update + ') called');
         }
-        NETDATA.chartRefresherRunsAfterParseDom++;
 
-        var now = Date.now();
-        NETDATA.chartRefresherLastRun = now;
+        if (typeof dont_clear_master === 'undefined') {
+            dont_clear_master = false;
+        }
 
-        if( now < NETDATA.options.on_scroll_refresher_stop_until ) {
-            NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
-                NETDATA.chartRefresher,
-                NETDATA.chartRefresherWaitTime()
-            );
+        if (typeof dont_update === 'undefined') {
+            dont_update = false;
+        }
 
-            // console.log('chartRefresher() end1 will run in ' + NETDATA.chartRefresherWaitTime().toString() + ' ms');
+        if (dont_clear_master !== true && NETDATA.globalPanAndZoom.isMaster(this)) {
+            if (this.debug) {
+                this.log('resetChart() diverting to clearMaster().');
+            }
+            // this will call us back with master === true
+            NETDATA.globalPanAndZoom.clearMaster();
             return;
         }
 
-        if( now < NETDATA.options.auto_refresher_stop_until ) {
-            NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
-                NETDATA.chartRefresher,
-                NETDATA.chartRefresherWaitTime()
-            );
+        this.clearSelection();
 
-            // console.log('chartRefresher() end2 will run in ' + NETDATA.chartRefresherWaitTime().toString() + ' ms');
-            return;
-        }
+        this.tm.pan_and_zoom_seq = 0;
 
-        if(NETDATA.options.pause === true) {
-            // console.log('auto-refresher is paused');
-            NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
-                NETDATA.chartRefresher,
-                NETDATA.chartRefresherWaitTime()
-            );
+        this.setMode('auto');
+        this.current.force_update_at = 0;
+        this.current.force_before_ms = null;
+        this.current.force_after_ms = null;
+        this.tm.last_autorefreshed = 0;
+        this.paused = false;
+        this.selected = false;
+        this.enabled = true;
+        // this.debug = false;
 
-            // console.log('chartRefresher() end3 will run in ' + NETDATA.chartRefresherWaitTime().toString() + ' ms');
-            return;
+        // do not update the chart here
+        // or the chart will flip-flop when it is the master
+        // of a selection sync and another chart becomes
+        // the new master
+
+        if (dont_update !== true && this.isVisible()) {
+            this.updateChart();
         }
+    };
 
-        if(typeof NETDATA.options.pauseCallback === 'function') {
-            // console.log('auto-refresher is calling pauseCallback');
+    this.updateChartPanOrZoom = function (after, before, callback) {
+        let logme = 'updateChartPanOrZoom(' + after + ', ' + before + '): ';
+        let ret = true;
 
-            NETDATA.options.pause = true;
-            NETDATA.options.pauseCallback();
-            NETDATA.chartRefresher();
+        NETDATA.globalPanAndZoom.delay();
+        NETDATA.globalSelectionSync.delay();
 
-            // console.log('chartRefresher() end4 (nested)');
-            return;
+        if (this.debug) {
+            this.log(logme);
         }
 
-        if(NETDATA.options.current.parallel_refresher === false) {
-            // console.log('auto-refresher is calling chartRefresherNoParallel(0)');
-            NETDATA.chartRefresherNoParallel(0, function() {
-                NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
-                    NETDATA.chartRefresher,
-                    NETDATA.options.current.idle_between_loops
-                );
-            });
-            // console.log('chartRefresher() end5 (no parallel, nested)');
-            return;
+        if (before < after) {
+            if (this.debug) {
+                this.log(logme + 'flipped parameters, rejecting it.');
+            }
+            return false;
         }
 
-        if(NETDATA.options.updated_dom === true) {
-            // the dom has been updated
-            // get the dom parts again
-            // console.log('auto-refresher is calling parseDom()');
-            NETDATA.parseDom(NETDATA.chartRefresher);
-            // console.log('chartRefresher() end6 (parseDom)');
-            return;
+        if (typeof this.fixed_min_duration === 'undefined') {
+            this.fixed_min_duration = Math.round((this.chartWidth() / 30) * this.chart.update_every * 1000);
         }
 
-        if(NETDATA.globalSelectionSync.active() === false) {
-            var parallel = [];
-            var targets = NETDATA.intersectionObserver.targets();
-            var len = targets.length;
-            var state;
-            while(len--) {
-                state = targets[len];
-                if(state.running === true || state.isVisible() === false)
-                    continue;
+        let min_duration = this.fixed_min_duration;
+        let current_duration = Math.round(this.view_before - this.view_after);
 
-                if(state.library.initialized === false) {
-                    if(state.library.enabled === true) {
-                        state.library.initialize(NETDATA.chartRefresher);
-                        //console.log('chartRefresher() end6 (library init)');
-                        return;
-                    }
-                    else {
-                        state.error('chart library "' + state.library_name + '" is not enabled.');
-                    }
-                }
+        // round the numbers
+        after = Math.round(after);
+        before = Math.round(before);
+
+        // align them to update_every
+        // stretching them further away
+        after -= after % this.data_update_every;
+        before += this.data_update_every - (before % this.data_update_every);
+
+        // the final wanted duration
+        let wanted_duration = before - after;
+
+        // to allow panning, accept just a point below our minimum
+        if ((current_duration - this.data_update_every) < min_duration) {
+            min_duration = current_duration - this.data_update_every;
+        }
 
-                if(NETDATA.scrollUp === true)
-                    parallel.unshift(state);
-                else
-                    parallel.push(state);
+        // we do it, but we adjust to minimum size and return false
+        // when the wanted size is below the current and the minimum
+        // and we zoom
+        if (wanted_duration < current_duration && wanted_duration < min_duration) {
+            if (this.debug) {
+                this.log(logme + 'too small: min_duration: ' + (min_duration / 1000).toString() + ', wanted: ' + (wanted_duration / 1000).toString());
             }
 
-            len = parallel.length;
-            while (len--) {
-                state = parallel[len];
-                // console.log('auto-refresher executing in parallel for ' + parallel.length.toString() + ' charts');
-                // this will execute the jobs in parallel
+            min_duration = this.fixed_min_duration;
+
+            let dt = (min_duration - wanted_duration) / 2;
+            before += dt;
+            after -= dt;
+            wanted_duration = before - after;
+            ret = false;
+        }
 
-                if (state.running === false)
-                    NETDATA.timeout.set(state.autoRefresh, 0);
+        let tolerance = this.data_update_every * 2;
+        let movement = Math.abs(before - this.view_before);
+
+        if (Math.abs(current_duration - wanted_duration) <= tolerance && movement <= tolerance && ret) {
+            if (this.debug) {
+                this.log(logme + 'REJECTING UPDATE: current/min duration: ' + (current_duration / 1000).toString() + '/' + (this.fixed_min_duration / 1000).toString() + ', wanted duration: ' + (wanted_duration / 1000).toString() + ', duration diff: ' + (Math.round(Math.abs(current_duration - wanted_duration) / 1000)).toString() + ', movement: ' + (movement / 1000).toString() + ', tolerance: ' + (tolerance / 1000).toString() + ', returning: ' + false);
             }
-            //else {
-            //    console.log('auto-refresher nothing to do');
-            //}
+            return false;
         }
 
-        // run the next refresh iteration
-        NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
-            NETDATA.chartRefresher,
-            NETDATA.chartRefresherWaitTime()
-        );
+        if (this.current.name === 'auto') {
+            this.log(logme + 'caller called me with mode: ' + this.current.name);
+            this.setMode('pan');
+        }
 
-        //console.log('chartRefresher() completed in ' + (Date.now() - now).toString() + ' ms');
-    };
+        if (this.debug) {
+            this.log(logme + 'ACCEPTING UPDATE: current/min duration: ' + (current_duration / 1000).toString() + '/' + (this.fixed_min_duration / 1000).toString() + ', wanted duration: ' + (wanted_duration / 1000).toString() + ', duration diff: ' + (Math.round(Math.abs(current_duration - wanted_duration) / 1000)).toString() + ', movement: ' + (movement / 1000).toString() + ', tolerance: ' + (tolerance / 1000).toString() + ', returning: ' + ret);
+        }
 
-    NETDATA.parseDom = function(callback) {
-        //console.log('parseDom()');
+        this.current.force_update_at = Date.now() + NETDATA.options.current.pan_and_zoom_delay;
+        this.current.force_after_ms = after;
+        this.current.force_before_ms = before;
+        NETDATA.globalPanAndZoom.setMaster(this, after, before);
 
-        NETDATA.options.last_page_scroll = Date.now();
-        NETDATA.options.updated_dom = false;
-        NETDATA.chartRefresherRunsAfterParseDom = 0;
+        if (ret && typeof callback === 'function') {
+            callback();
+        }
 
-        var targets = $('div[data-netdata]'); //.filter(':visible');
+        return ret;
+    };
 
-        if(NETDATA.options.debug.main_loop === true)
-            console.log('DOM updated - there are ' + targets.length + ' charts on page.');
+    this.updateChartPanOrZoomAsyncTimeOutId = undefined;
+    this.updateChartPanOrZoomAsync = function (after, before, callback) {
+        NETDATA.globalPanAndZoom.delay();
+        NETDATA.globalSelectionSync.delay();
 
-        NETDATA.intersectionObserver.globalReset();
-        NETDATA.options.targets = [];
-        var len = targets.length;
-        while(len--) {
-            // the initialization will take care of sizing
-            // and the "loading..." message
-            var state = NETDATA.chartState(targets[len]);
-            NETDATA.options.targets.push(state);
-            NETDATA.intersectionObserver.observe(state);
+        if (NETDATA.globalPanAndZoom.isMaster(this) === false) {
+            this.pauseChart();
+            NETDATA.globalPanAndZoom.setMaster(this, after, before);
+            // NETDATA.globalSelectionSync.stop();
+            NETDATA.globalSelectionSync.setMaster(this);
         }
 
-        if(NETDATA.globalChartUnderlay.isActive() === true)
-            NETDATA.globalChartUnderlay.setup();
-        else
-            NETDATA.globalChartUnderlay.clear();
+        if (this.updateChartPanOrZoomAsyncTimeOutId) {
+            NETDATA.timeout.clear(this.updateChartPanOrZoomAsyncTimeOutId);
+        }
 
-        if(typeof callback === 'function')
-            return callback();
+        NETDATA.timeout.set(function () {
+            that.updateChartPanOrZoomAsyncTimeOutId = undefined;
+            that.updateChartPanOrZoom(after, before, callback);
+        }, 0);
     };
 
-    // this is the main function - where everything starts
-    NETDATA.started = false;
-    NETDATA.start = function() {
-        // this should be called only once
+    let __unitsConversionLastUnits = undefined;
+    let __unitsConversionLastUnitsDesired = undefined;
+    let __unitsConversionLastMin = undefined;
+    let __unitsConversionLastMax = undefined;
+    let __unitsConversion = function (value) {
+        return value;
+    };
+    this.unitsConversionSetup = function (min, max) {
+        if (this.units !== __unitsConversionLastUnits
+            || this.units_desired !== __unitsConversionLastUnitsDesired
+            || min !== __unitsConversionLastMin
+            || max !== __unitsConversionLastMax) {
+
+            __unitsConversionLastUnits = this.units;
+            __unitsConversionLastUnitsDesired = this.units_desired;
+            __unitsConversionLastMin = min;
+            __unitsConversionLastMax = max;
+
+            __unitsConversion = NETDATA.unitsConversion.get(this.uuid, min, max, this.units, this.units_desired, this.units_common, function (units) {
+                // console.log('switching units from ' + that.units.toString() + ' to ' + units.toString());
+                that.units_current = units;
+                that.legendSetUnitsString(that.units_current);
+            });
+        }
+    };
 
-        if(NETDATA.started === true) {
-            console.log('netdata is already started');
+    let __legendFormatValueChartDecimalsLastMin = undefined;
+    let __legendFormatValueChartDecimalsLastMax = undefined;
+    let __legendFormatValueChartDecimals = -1;
+    let __intlNumberFormat = null;
+    this.legendFormatValueDecimalsFromMinMax = function (min, max) {
+        if (min === __legendFormatValueChartDecimalsLastMin && max === __legendFormatValueChartDecimalsLastMax) {
             return;
         }
 
-        NETDATA.started = true;
-        NETDATA.options.page_is_visible = true;
+        this.unitsConversionSetup(min, max);
+        if (__unitsConversion !== null) {
+            min = __unitsConversion(min);
+            max = __unitsConversion(max);
 
-        $(window).blur(function() {
-            if(NETDATA.options.current.stop_updates_when_focus_is_lost === true) {
-                NETDATA.options.page_is_visible = false;
-                if(NETDATA.options.debug.focus === true)
-                    console.log('Lost Focus!');
+            if (typeof min !== 'number' || typeof max !== 'number') {
+                return;
             }
-        });
+        }
 
-        $(window).focus(function() {
-            if(NETDATA.options.current.stop_updates_when_focus_is_lost === true) {
-                NETDATA.options.page_is_visible = true;
-                if(NETDATA.options.debug.focus === true)
-                    console.log('Focus restored!');
-            }
-        });
+        __legendFormatValueChartDecimalsLastMin = min;
+        __legendFormatValueChartDecimalsLastMax = max;
+
+        let old = __legendFormatValueChartDecimals;
 
-        if(typeof document.hasFocus === 'function' && !document.hasFocus()) {
-            if(NETDATA.options.current.stop_updates_when_focus_is_lost === true) {
-                NETDATA.options.page_is_visible = false;
-                if(NETDATA.options.debug.focus === true)
-                    console.log('Document has no focus!');
+        if (this.data !== null && this.data.min === this.data.max)
+        // it is a fixed number, let the visualizer decide based on the value
+        {
+            __legendFormatValueChartDecimals = -1;
+        } else if (this.value_decimal_detail !== -1)
+        // there is an override
+        {
+            __legendFormatValueChartDecimals = this.value_decimal_detail;
+        } else {
+            // ok, let's calculate the proper number of decimal points
+            let delta;
+
+            if (min === max) {
+                delta = Math.abs(min);
+            } else {
+                delta = Math.abs(max - min);
+            }
+
+            if (delta > 1000) {
+                __legendFormatValueChartDecimals = 0;
+            } else if (delta > 10) {
+                __legendFormatValueChartDecimals = 1;
+            } else if (delta > 1) {
+                __legendFormatValueChartDecimals = 2;
+            } else if (delta > 0.1) {
+                __legendFormatValueChartDecimals = 2;
+            } else if (delta > 0.01) {
+                __legendFormatValueChartDecimals = 4;
+            } else if (delta > 0.001) {
+                __legendFormatValueChartDecimals = 5;
+            } else if (delta > 0.0001) {
+                __legendFormatValueChartDecimals = 6;
+            } else {
+                __legendFormatValueChartDecimals = 7;
+            }
+        }
+
+        if (__legendFormatValueChartDecimals !== old) {
+            if (__legendFormatValueChartDecimals < 0) {
+                __intlNumberFormat = null;
+            } else {
+                __intlNumberFormat = NETDATA.fastNumberFormat.get(
+                    __legendFormatValueChartDecimals,
+                    __legendFormatValueChartDecimals
+                );
             }
         }
+    };
 
-        // bootstrap tab switching
-        $('a[data-toggle="tab"]').on('shown.bs.tab', NETDATA.onscroll);
-
-        // bootstrap modal switching
-        var $modal = $('.modal');
-        $modal.on('hidden.bs.modal', NETDATA.onscroll);
-        $modal.on('shown.bs.modal', NETDATA.onscroll);
+    this.legendFormatValue = function (value) {
+        if (typeof value !== 'number') {
+            return '-';
+        }
 
-        // bootstrap collapse switching
-        var $collapse = $('.collapse');
-        $collapse.on('hidden.bs.collapse', NETDATA.onscroll);
-        $collapse.on('shown.bs.collapse', NETDATA.onscroll);
+        value = __unitsConversion(value);
 
-        NETDATA.parseDom(NETDATA.chartRefresher);
+        if (typeof value !== 'number') {
+            return value;
+        }
 
-        // Alarms initialization
-        setTimeout(NETDATA.alarms.init, 1000);
+        if (__intlNumberFormat !== null) {
+            return __intlNumberFormat.format(value);
+        }
 
-        // Registry initialization
-        setTimeout(NETDATA.registry.init, netdataRegistryAfterMs);
+        let dmin, dmax;
+        if (this.value_decimal_detail !== -1) {
+            dmin = dmax = this.value_decimal_detail;
+        } else {
+            dmin = 0;
+            let abs = (value < 0) ? -value : value;
+            if (abs > 1000) {
+                dmax = 0;
+            } else if (abs > 10) {
+                dmax = 1;
+            } else if (abs > 1) {
+                dmax = 2;
+            } else if (abs > 0.1) {
+                dmax = 2;
+            } else if (abs > 0.01) {
+                dmax = 4;
+            } else if (abs > 0.001) {
+                dmax = 5;
+            } else if (abs > 0.0001) {
+                dmax = 6;
+            } else {
+                dmax = 7;
+            }
+        }
 
-        if(typeof netdataCallback === 'function')
-            netdataCallback();
+        return NETDATA.fastNumberFormat.get(dmin, dmax).format(value);
     };
 
-    NETDATA.globalReset = function() {
-        NETDATA.intersectionObserver.globalReset();
-        NETDATA.globalSelectionSync.globalReset();
-        NETDATA.globalPanAndZoom.globalReset();
-        NETDATA.chartRegistry.globalReset();
-        NETDATA.commonMin.globalReset();
-        NETDATA.commonMax.globalReset();
-        NETDATA.commonColors.globalReset();
-        NETDATA.unitsConversion.globalReset();
-        NETDATA.options.targets = [];
-        NETDATA.parseDom();
-        NETDATA.unpause();
-    };
+    this.legendSetLabelValue = function (label, value) {
+        let series = this.element_legend_childs.series[label];
+        if (typeof series === 'undefined') {
+            return;
+        }
+        if (series.value === null && series.user === null) {
+            return;
+        }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // peity
+        /*
+        // this slows down firefox and edge significantly
+        // since it requires to use innerHTML(), instead of innerText()
 
-    NETDATA.peityInitialize = function(callback) {
-        if(typeof netdataNoPeitys === 'undefined' || !netdataNoPeitys) {
-            $.ajax({
-                url: NETDATA.peity_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function() {
-                NETDATA.registerChartLibrary('peity', NETDATA.peity_js);
-            })
-            .fail(function() {
-                NETDATA.chartLibraries.peity.enabled = false;
-                NETDATA.error(100, NETDATA.peity_js);
-            })
-            .always(function() {
-                if(typeof callback === "function")
-                    return callback();
-            });
+        // if the value has not changed, skip DOM update
+        //if (series.last === value) return;
+
+        let s, r;
+        if (typeof value === 'number') {
+            let v = Math.abs(value);
+            s = r = this.legendFormatValue(value);
+
+            if (typeof series.last === 'number') {
+                if (v > series.last) s += '<i class="fas fa-angle-up" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
+                else if (v < series.last) s += '<i class="fas fa-angle-down" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
+                else s += '<i class="fas fa-angle-left" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
+            }
+            else s += '<i class="fas fa-angle-right" style="width: 8px; text-align: center; overflow: hidden; vertical-align: middle;"></i>';
+
+            series.last = v;
         }
         else {
-            NETDATA.chartLibraries.peity.enabled = false;
-            if(typeof callback === "function")
-                return callback();
+            if (value === null)
+                s = r = '';
+            else
+                s = r = value;
+
+            series.last = value;
         }
-    };
+        */
 
-    NETDATA.peityChartUpdate = function(state, data) {
-        state.peity_instance.innerHTML = data.result;
+        let s = this.legendFormatValue(value);
 
-        if(state.peity_options.stroke !== state.chartCustomColors()[0]) {
-            state.peity_options.stroke = state.chartCustomColors()[0];
-            if(state.chart.chart_type === 'line')
-                state.peity_options.fill = NETDATA.themes.current.background;
-            else
-                state.peity_options.fill = NETDATA.colorLuminance(state.chartCustomColors()[0], NETDATA.chartDefaults.fill_luminance);
+        // caching: do not update the update to show the same value again
+        if (s === series.last_shown_value) {
+            return;
         }
+        series.last_shown_value = s;
 
-        $(state.peity_instance).peity('line', state.peity_options);
-        return true;
+        if (series.value !== null) {
+            series.value.innerText = s;
+        }
+        if (series.user !== null) {
+            series.user.innerText = s;
+        }
     };
 
-    NETDATA.peityChartCreate = function(state, data) {
-        state.peity_instance = document.createElement('div');
-        state.element_chart.appendChild(state.peity_instance);
+    this.legendSetDateString = function (date) {
+        if (this.element_legend_childs.title_date !== null && date !== this.tmp.__last_shown_legend_date) {
+            this.element_legend_childs.title_date.innerText = date;
+            this.tmp.__last_shown_legend_date = date;
+        }
+    };
 
-        state.peity_options = {
-            stroke: NETDATA.themes.current.foreground,
-            strokeWidth: NETDATA.dataAttribute(state.element, 'peity-strokewidth', 1),
-            width: state.chartWidth(),
-            height: state.chartHeight(),
-            fill: NETDATA.themes.current.foreground
-        };
+    this.legendSetTimeString = function (time) {
+        if (this.element_legend_childs.title_time !== null && time !== this.tmp.__last_shown_legend_time) {
+            this.element_legend_childs.title_time.innerText = time;
+            this.tmp.__last_shown_legend_time = time;
+        }
+    };
 
-        NETDATA.peityChartUpdate(state, data);
-        return true;
+    this.legendSetUnitsString = function (units) {
+        if (this.element_legend_childs.title_units !== null && units !== this.tmp.__last_shown_legend_units) {
+            this.element_legend_childs.title_units.innerText = units;
+            this.tmp.__last_shown_legend_units = units;
+        }
     };
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // sparkline
+    this.legendSetDateLast = {
+        ms: 0,
+        date: undefined,
+        time: undefined
+    };
 
-    NETDATA.sparklineInitialize = function(callback) {
-        if(typeof netdataNoSparklines === 'undefined' || !netdataNoSparklines) {
-            $.ajax({
-                url: NETDATA.sparkline_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function() {
-                NETDATA.registerChartLibrary('sparkline', NETDATA.sparkline_js);
-            })
-            .fail(function() {
-                NETDATA.chartLibraries.sparkline.enabled = false;
-                NETDATA.error(100, NETDATA.sparkline_js);
-            })
-            .always(function() {
-                if(typeof callback === "function")
-                    return callback();
-            });
-        }
-        else {
-            NETDATA.chartLibraries.sparkline.enabled = false;
-            if(typeof callback === "function")
-                return callback();
+    this.legendSetDate = function (ms) {
+        if (typeof ms !== 'number') {
+            this.legendShowUndefined();
+            return;
         }
-    };
 
-    NETDATA.sparklineChartUpdate = function(state, data) {
-        state.sparkline_options.width = state.chartWidth();
-        state.sparkline_options.height = state.chartHeight();
+        if (this.legendSetDateLast.ms !== ms) {
+            let d = new Date(ms);
+            this.legendSetDateLast.ms = ms;
+            this.legendSetDateLast.date = NETDATA.dateTime.localeDateString(d);
+            this.legendSetDateLast.time = NETDATA.dateTime.localeTimeString(d);
+        }
 
-        $(state.element_chart).sparkline(data.result, state.sparkline_options);
-        return true;
+        this.legendSetDateString(this.legendSetDateLast.date);
+        this.legendSetTimeString(this.legendSetDateLast.time);
+        this.legendSetUnitsString(this.units_current)
     };
 
-    NETDATA.sparklineChartCreate = function(state, data) {
-        var type = NETDATA.dataAttribute(state.element, 'sparkline-type', 'line');
-        var lineColor = NETDATA.dataAttribute(state.element, 'sparkline-linecolor', state.chartCustomColors()[0]);
-        var fillColor = NETDATA.dataAttribute(state.element, 'sparkline-fillcolor', ((state.chart.chart_type === 'line')?NETDATA.themes.current.background:NETDATA.colorLuminance(lineColor, NETDATA.chartDefaults.fill_luminance)));
-        var chartRangeMin = NETDATA.dataAttribute(state.element, 'sparkline-chartrangemin', undefined);
-        var chartRangeMax = NETDATA.dataAttribute(state.element, 'sparkline-chartrangemax', undefined);
-        var composite = NETDATA.dataAttribute(state.element, 'sparkline-composite', undefined);
-        var enableTagOptions = NETDATA.dataAttribute(state.element, 'sparkline-enabletagoptions', undefined);
-        var tagOptionPrefix = NETDATA.dataAttribute(state.element, 'sparkline-tagoptionprefix', undefined);
-        var tagValuesAttribute = NETDATA.dataAttribute(state.element, 'sparkline-tagvaluesattribute', undefined);
-        var disableHiddenCheck = NETDATA.dataAttribute(state.element, 'sparkline-disablehiddencheck', undefined);
-        var defaultPixelsPerValue = NETDATA.dataAttribute(state.element, 'sparkline-defaultpixelspervalue', undefined);
-        var spotColor = NETDATA.dataAttribute(state.element, 'sparkline-spotcolor', undefined);
-        var minSpotColor = NETDATA.dataAttribute(state.element, 'sparkline-minspotcolor', undefined);
-        var maxSpotColor = NETDATA.dataAttribute(state.element, 'sparkline-maxspotcolor', undefined);
-        var spotRadius = NETDATA.dataAttribute(state.element, 'sparkline-spotradius', undefined);
-        var valueSpots = NETDATA.dataAttribute(state.element, 'sparkline-valuespots', undefined);
-        var highlightSpotColor = NETDATA.dataAttribute(state.element, 'sparkline-highlightspotcolor', undefined);
-        var highlightLineColor = NETDATA.dataAttribute(state.element, 'sparkline-highlightlinecolor', undefined);
-        var lineWidth = NETDATA.dataAttribute(state.element, 'sparkline-linewidth', undefined);
-        var normalRangeMin = NETDATA.dataAttribute(state.element, 'sparkline-normalrangemin', undefined);
-        var normalRangeMax = NETDATA.dataAttribute(state.element, 'sparkline-normalrangemax', undefined);
-        var drawNormalOnTop = NETDATA.dataAttribute(state.element, 'sparkline-drawnormalontop', undefined);
-        var xvalues = NETDATA.dataAttribute(state.element, 'sparkline-xvalues', undefined);
-        var chartRangeClip = NETDATA.dataAttribute(state.element, 'sparkline-chartrangeclip', undefined);
-        var chartRangeMinX = NETDATA.dataAttribute(state.element, 'sparkline-chartrangeminx', undefined);
-        var chartRangeMaxX = NETDATA.dataAttribute(state.element, 'sparkline-chartrangemaxx', undefined);
-        var disableInteraction = NETDATA.dataAttributeBoolean(state.element, 'sparkline-disableinteraction', false);
-        var disableTooltips = NETDATA.dataAttributeBoolean(state.element, 'sparkline-disabletooltips', false);
-        var disableHighlight = NETDATA.dataAttributeBoolean(state.element, 'sparkline-disablehighlight', false);
-        var highlightLighten = NETDATA.dataAttribute(state.element, 'sparkline-highlightlighten', 1.4);
-        var highlightColor = NETDATA.dataAttribute(state.element, 'sparkline-highlightcolor', undefined);
-        var tooltipContainer = NETDATA.dataAttribute(state.element, 'sparkline-tooltipcontainer', undefined);
-        var tooltipClassname = NETDATA.dataAttribute(state.element, 'sparkline-tooltipclassname', undefined);
-        var tooltipFormat = NETDATA.dataAttribute(state.element, 'sparkline-tooltipformat', undefined);
-        var tooltipPrefix = NETDATA.dataAttribute(state.element, 'sparkline-tooltipprefix', undefined);
-        var tooltipSuffix = NETDATA.dataAttribute(state.element, 'sparkline-tooltipsuffix', ' ' + state.units_current);
-        var tooltipSkipNull = NETDATA.dataAttributeBoolean(state.element, 'sparkline-tooltipskipnull', true);
-        var tooltipValueLookups = NETDATA.dataAttribute(state.element, 'sparkline-tooltipvaluelookups', undefined);
-        var tooltipFormatFieldlist = NETDATA.dataAttribute(state.element, 'sparkline-tooltipformatfieldlist', undefined);
-        var tooltipFormatFieldlistKey = NETDATA.dataAttribute(state.element, 'sparkline-tooltipformatfieldlistkey', undefined);
-        var numberFormatter = NETDATA.dataAttribute(state.element, 'sparkline-numberformatter', function(n){ return n.toFixed(2); });
-        var numberDigitGroupSep = NETDATA.dataAttribute(state.element, 'sparkline-numberdigitgroupsep', undefined);
-        var numberDecimalMark = NETDATA.dataAttribute(state.element, 'sparkline-numberdecimalmark', undefined);
-        var numberDigitGroupCount = NETDATA.dataAttribute(state.element, 'sparkline-numberdigitgroupcount', undefined);
-        var animatedZooms = NETDATA.dataAttributeBoolean(state.element, 'sparkline-animatedzooms', false);
-
-        if(spotColor === 'disable') spotColor='';
-        if(minSpotColor === 'disable') minSpotColor='';
-        if(maxSpotColor === 'disable') maxSpotColor='';
-
-        // state.log('sparkline type ' + type + ', lineColor: ' + lineColor + ', fillColor: ' + fillColor);
-
-        state.sparkline_options = {
-            type: type,
-            lineColor: lineColor,
-            fillColor: fillColor,
-            chartRangeMin: chartRangeMin,
-            chartRangeMax: chartRangeMax,
-            composite: composite,
-            enableTagOptions: enableTagOptions,
-            tagOptionPrefix: tagOptionPrefix,
-            tagValuesAttribute: tagValuesAttribute,
-            disableHiddenCheck: disableHiddenCheck,
-            defaultPixelsPerValue: defaultPixelsPerValue,
-            spotColor: spotColor,
-            minSpotColor: minSpotColor,
-            maxSpotColor: maxSpotColor,
-            spotRadius: spotRadius,
-            valueSpots: valueSpots,
-            highlightSpotColor: highlightSpotColor,
-            highlightLineColor: highlightLineColor,
-            lineWidth: lineWidth,
-            normalRangeMin: normalRangeMin,
-            normalRangeMax: normalRangeMax,
-            drawNormalOnTop: drawNormalOnTop,
-            xvalues: xvalues,
-            chartRangeClip: chartRangeClip,
-            chartRangeMinX: chartRangeMinX,
-            chartRangeMaxX: chartRangeMaxX,
-            disableInteraction: disableInteraction,
-            disableTooltips: disableTooltips,
-            disableHighlight: disableHighlight,
-            highlightLighten: highlightLighten,
-            highlightColor: highlightColor,
-            tooltipContainer: tooltipContainer,
-            tooltipClassname: tooltipClassname,
-            tooltipChartTitle: state.title,
-            tooltipFormat: tooltipFormat,
-            tooltipPrefix: tooltipPrefix,
-            tooltipSuffix: tooltipSuffix,
-            tooltipSkipNull: tooltipSkipNull,
-            tooltipValueLookups: tooltipValueLookups,
-            tooltipFormatFieldlist: tooltipFormatFieldlist,
-            tooltipFormatFieldlistKey: tooltipFormatFieldlistKey,
-            numberFormatter: numberFormatter,
-            numberDigitGroupSep: numberDigitGroupSep,
-            numberDecimalMark: numberDecimalMark,
-            numberDigitGroupCount: numberDigitGroupCount,
-            animatedZooms: animatedZooms,
-            width: state.chartWidth(),
-            height: state.chartHeight()
-        };
+    this.legendShowUndefined = function () {
+        this.legendSetDateString(this.legendPluginModuleString(false));
+        this.legendSetTimeString(this.chart.context.toString());
+        // this.legendSetUnitsString(' ');
 
-        $(state.element_chart).sparkline(data.result, state.sparkline_options);
+        if (this.data && this.element_legend_childs.series !== null) {
+            let labels = this.data.dimension_names;
+            let i = labels.length;
+            while (i--) {
+                let label = labels[i];
 
-        return true;
+                if (typeof label === 'undefined' || typeof this.element_legend_childs.series[label] === 'undefined') {
+                    continue;
+                }
+                this.legendSetLabelValue(label, null);
+            }
+        }
     };
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // dygraph
+    this.legendShowLatestValues = function () {
+        if (this.chart === null) {
+            return;
+        }
+        if (this.selected) {
+            return;
+        }
 
-    NETDATA.dygraph = {
-        smooth: false
-    };
+        if (this.data === null || this.element_legend_childs.series === null) {
+            this.legendShowUndefined();
+            return;
+        }
 
-    NETDATA.dygraphToolboxPanAndZoom = function(state, after, before) {
-        if(after < state.netdata_first)
-            after = state.netdata_first;
+        let show_undefined = true;
+        if (Math.abs(this.netdata_last - this.view_before) <= this.data_update_every) {
+            show_undefined = false;
+        }
 
-        if(before > state.netdata_last)
-            before = state.netdata_last;
+        if (show_undefined) {
+            this.legendShowUndefined();
+            return;
+        }
 
-        state.setMode('zoom');
-        NETDATA.globalSelectionSync.stop();
-        NETDATA.globalSelectionSync.delay();
-        state.tmp.dygraph_user_action = true;
-        state.tmp.dygraph_force_zoom = true;
-        // state.log('toolboxPanAndZoom');
-        state.updateChartPanOrZoom(after, before);
-        NETDATA.globalPanAndZoom.setMaster(state, after, before);
-    };
+        this.legendSetDate(this.view_before);
 
-    NETDATA.dygraphSetSelection = function(state, t) {
-        if(typeof state.tmp.dygraph_instance !== 'undefined') {
-            var r = state.calculateRowForTime(t);
-            if(r !== -1) {
-                state.tmp.dygraph_instance.setSelection(r);
-                return true;
+        let labels = this.data.dimension_names;
+        let i = labels.length;
+        while (i--) {
+            let label = labels[i];
+
+            if (typeof label === 'undefined') {
+                continue;
             }
-            else {
-                state.tmp.dygraph_instance.clearSelection();
-                state.legendShowUndefined();
+            if (typeof this.element_legend_childs.series[label] === 'undefined') {
+                continue;
             }
+
+            this.legendSetLabelValue(label, this.data.view_latest_values[i]);
         }
+    };
 
-        return false;
+    this.legendReset = function () {
+        this.legendShowLatestValues();
     };
 
-    NETDATA.dygraphClearSelection = function(state) {
-        if(typeof state.tmp.dygraph_instance !== 'undefined') {
-            state.tmp.dygraph_instance.clearSelection();
-        }
-        return true;
+    // this should be called just ONCE per dimension per chart
+    this.__chartDimensionColor = function (label) {
+        let c = NETDATA.commonColors.get(this, label);
+
+        // it is important to maintain a list of colors
+        // for this chart only, since the chart library
+        // uses this to assign colors to dimensions in the same
+        // order the dimension are given to it
+        this.colors.push(c);
+
+        return c;
     };
 
-    NETDATA.dygraphSmoothInitialize = function(callback) {
-        $.ajax({
-            url: NETDATA.dygraph_smooth_js,
-            cache: true,
-            dataType: "script",
-            xhrFields: { withCredentials: true } // required for the cookie
-        })
-        .done(function() {
-            NETDATA.dygraph.smooth = true;
-            smoothPlotter.smoothing = 0.3;
-        })
-        .fail(function() {
-            NETDATA.dygraph.smooth = false;
-        })
-        .always(function() {
-            if(typeof callback === "function")
-                return callback();
-        });
+    this.chartPrepareColorPalette = function () {
+        NETDATA.commonColors.refill(this);
     };
 
-    NETDATA.dygraphInitialize = function(callback) {
-        if(typeof netdataNoDygraphs === 'undefined' || !netdataNoDygraphs) {
-            $.ajax({
-                url: NETDATA.dygraph_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function() {
-                NETDATA.registerChartLibrary('dygraph', NETDATA.dygraph_js);
-            })
-            .fail(function() {
-                NETDATA.chartLibraries.dygraph.enabled = false;
-                NETDATA.error(100, NETDATA.dygraph_js);
-            })
-            .always(function() {
-                if(NETDATA.chartLibraries.dygraph.enabled === true && NETDATA.options.current.smooth_plot === true)
-                    NETDATA.dygraphSmoothInitialize(callback);
-                else if(typeof callback === "function")
-                    return callback();
-            });
+    // get the ordered list of chart colors
+    // this includes user defined colors
+    this.chartCustomColors = function () {
+        this.chartPrepareColorPalette();
+
+        let colors;
+        if (this.colors_custom.length) {
+            colors = this.colors_custom;
+        } else {
+            colors = this.colors;
         }
-        else {
-            NETDATA.chartLibraries.dygraph.enabled = false;
-            if(typeof callback === "function")
-                return callback();
+
+        if (this.debug) {
+            this.log("chartCustomColors() returns:");
+            this.log(colors);
         }
+
+        return colors;
     };
 
-    NETDATA.dygraphChartUpdate = function(state, data) {
-        var dygraph = state.tmp.dygraph_instance;
+    // get the ordered list of chart ASSIGNED colors
+    // (this returns only the colors that have been
+    //  assigned to dimensions, prepended with any
+    // custom colors defined)
+    this.chartColors = function () {
+        this.chartPrepareColorPalette();
 
-        if(typeof dygraph === 'undefined')
-            return NETDATA.dygraphChartCreate(state, data);
+        if (this.debug) {
+            this.log("chartColors() returns:");
+            this.log(this.colors);
+        }
 
-        // when the chart is not visible, and hidden
-        // if there is a window resize, dygraph detects
-        // its element size as 0x0.
-        // this will make it re-appear properly
+        return this.colors;
+    };
 
-        if(state.tm.last_unhidden > state.tmp.dygraph_last_rendered)
-            dygraph.resize();
+    this.legendPluginModuleString = function (withContext) {
+        let str = ' ';
+        let context = '';
 
-        var options = {
-                file: data.result.data,
-                colors: state.chartColors(),
-                labels: data.result.labels,
-                //labelsDivWidth: state.chartWidth() - 70,
-                includeZero: state.tmp.dygraph_include_zero,
-                visibility: state.dimensions_visibility.selected2BooleanArray(state.data.dimension_names)
-        };
+        if (typeof this.chart !== 'undefined') {
+            if (withContext && typeof this.chart.context === 'string') {
+                context = this.chart.context;
+            }
 
-        if(state.tmp.dygraph_chart_type === 'stacked') {
-            if(options.includeZero === true && state.dimensions_visibility.countSelected() < options.visibility.length)
-                options.includeZero = 0;
-        }
+            if (typeof this.chart.plugin === 'string' && this.chart.plugin !== '') {
+                str = this.chart.plugin;
 
-        if(!NETDATA.chartLibraries.dygraph.isSparkline(state)) {
-            options.ylabel = state.units_current; // (state.units_desired === 'auto')?"":state.units_current;
-        }
+                if (str.endsWith(".plugin")) {
+                    str = str.substring(0, str.length - 7);
+                }
 
-        if(state.tmp.dygraph_force_zoom === true) {
-            if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                state.log('dygraphChartUpdate() forced zoom update');
+                if (typeof this.chart.module === 'string' && this.chart.module !== '') {
+                    str += ':' + this.chart.module;
+                }
 
-            options.dateWindow = (state.requested_padding !== null)?[ state.view_after, state.view_before ]:null;
-            //options.isZoomedIgnoreProgrammaticZoom = true;
-            state.tmp.dygraph_force_zoom = false;
-        }
-        else if(state.current.name !== 'auto') {
-            if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                state.log('dygraphChartUpdate() loose update');
+                if (withContext && context !== '') {
+                    str += ', ' + context;
+                }
+            }
+            else if (withContext && context !== '') {
+                str = context;
+            }
         }
-        else {
-            if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                state.log('dygraphChartUpdate() strict update');
 
-            options.dateWindow = (state.requested_padding !== null)?[ state.view_after, state.view_before ]:null;
-            //options.isZoomedIgnoreProgrammaticZoom = true;
+        return str;
+    };
+
+    this.legendResolutionTooltip = function () {
+        if (!this.chart) {
+            return '';
         }
 
-        options.valueRange = state.tmp.dygraph_options.valueRange;
+        let collected = this.chart.update_every;
+        let viewed = (this.data) ? this.data.view_update_every : collected;
 
-        var oldMax = null, oldMin = null;
-        if (state.tmp.__commonMin !== null) {
-            state.data.min = state.tmp.dygraph_instance.axes_[0].extremeRange[0];
-            oldMin = options.valueRange[0] = NETDATA.commonMin.get(state);
-        }
-        if (state.tmp.__commonMax !== null) {
-            state.data.max = state.tmp.dygraph_instance.axes_[0].extremeRange[1];
-            oldMax = options.valueRange[1] = NETDATA.commonMax.get(state);
+        if (collected === viewed) {
+            return "resolution " + NETDATA.seconds4human(collected);
         }
 
-        if(state.tmp.dygraph_smooth_eligible === true) {
-            if((NETDATA.options.current.smooth_plot === true && state.tmp.dygraph_options.plotter !== smoothPlotter)
-                || (NETDATA.options.current.smooth_plot === false && state.tmp.dygraph_options.plotter === smoothPlotter)) {
-                NETDATA.dygraphChartCreate(state, data);
-                return;
+        return "resolution " + NETDATA.seconds4human(viewed) + ", collected every " + NETDATA.seconds4human(collected);
+    };
+
+    this.legendUpdateDOM = function () {
+        let needed = false, dim, keys, len;
+
+        // check that the legend DOM is up to date for the downloaded dimensions
+        if (typeof this.element_legend_childs.series !== 'object' || this.element_legend_childs.series === null) {
+            // this.log('the legend does not have any series - requesting legend update');
+            needed = true;
+        } else if (this.data === null) {
+            // this.log('the chart does not have any data - requesting legend update');
+            needed = true;
+        } else if (typeof this.element_legend_childs.series.labels_key === 'undefined') {
+            needed = true;
+        } else {
+            let labels = this.data.dimension_names.toString();
+            if (labels !== this.element_legend_childs.series.labels_key) {
+                needed = true;
+
+                if (this.debug) {
+                    this.log('NEW LABELS: "' + labels + '" NOT EQUAL OLD LABELS: "' + this.element_legend_childs.series.labels_key + '"');
+                }
             }
         }
 
-        if(netdataSnapshotData !== null && NETDATA.globalPanAndZoom.isActive() === true && NETDATA.globalPanAndZoom.isMaster(state) === false) {
-            // pan and zoom on snapshots
-            options.dateWindow = [ NETDATA.globalPanAndZoom.force_after_ms, NETDATA.globalPanAndZoom.force_before_ms ];
-            //options.isZoomedIgnoreProgrammaticZoom = true;
+        if (needed === false) {
+            // make sure colors available
+            this.chartPrepareColorPalette();
+
+            // do we have to update the current values?
+            // we do this, only when the visible chart is current
+            if (Math.abs(this.netdata_last - this.view_before) <= this.data_update_every) {
+                if (this.debug) {
+                    this.log('chart is in latest position... updating values on legend...');
+                }
+
+                //let labels = this.data.dimension_names;
+                //let i = labels.length;
+                //while (i--)
+                //  this.legendSetLabelValue(labels[i], this.data.view_latest_values[i]);
+            }
+            return;
         }
 
-        if(NETDATA.chartLibraries.dygraph.isLogScale(state) === true) {
-            if(Array.isArray(options.valueRange) && options.valueRange[0] <= 0)
-                options.valueRange[0] = null;
+        if (this.colors === null) {
+            // this is the first time we update the chart
+            // let's assign colors to all dimensions
+            if (this.library.track_colors()) {
+                this.colors = [];
+                keys = Object.keys(this.chart.dimensions);
+                len = keys.length;
+                for (let i = 0; i < len; i++) {
+                    NETDATA.commonColors.get(this, this.chart.dimensions[keys[i]].name);
+                }
+            }
         }
 
-        dygraph.updateOptions(options);
+        // we will re-generate the colors for the chart
+        // based on the dimensions this result has data for
+        this.colors = [];
 
-        var redraw = false;
-        if(oldMin !== null && oldMin > state.tmp.dygraph_instance.axes_[0].extremeRange[0]) {
-            state.data.min = state.tmp.dygraph_instance.axes_[0].extremeRange[0];
-            options.valueRange[0] = NETDATA.commonMin.get(state);
-            redraw = true;
-        }
-        if(oldMax !== null && oldMax < state.tmp.dygraph_instance.axes_[0].extremeRange[1]) {
-            state.data.max = state.tmp.dygraph_instance.axes_[0].extremeRange[1];
-            options.valueRange[1] = NETDATA.commonMax.get(state);
-            redraw = true;
+        if (this.debug) {
+            this.log('updating Legend DOM');
         }
 
-        if(redraw === true) {
-            // state.log('forcing redraw to adapt to common- min/max');
-            dygraph.updateOptions(options);
-        }
+        // mark all dimensions as invalid
+        this.dimensions_visibility.invalidateAll();
 
-        state.tmp.dygraph_last_rendered = Date.now();
-        return true;
-    };
+        const genLabel = function (state, parent, dim, name, count) {
+            let color = state.__chartDimensionColor(name);
 
-    NETDATA.dygraphChartCreate = function(state, data) {
-        if(NETDATA.options.debug.dygraph === true || state.debug === true)
-            state.log('dygraphChartCreate()');
-
-        state.tmp.dygraph_chart_type = NETDATA.dataAttribute(state.element, 'dygraph-type', state.chart.chart_type);
-        if(state.tmp.dygraph_chart_type === 'stacked' && data.dimensions === 1) state.tmp.dygraph_chart_type = 'area';
-        if(state.tmp.dygraph_chart_type === 'stacked' && NETDATA.chartLibraries.dygraph.isLogScale(state) === true) state.tmp.dygraph_chart_type = 'area';
-
-        var highlightCircleSize = (NETDATA.chartLibraries.dygraph.isSparkline(state) === true)?3:4;
-
-        var smooth = (NETDATA.dygraph.smooth === true)
-            ?(NETDATA.dataAttributeBoolean(state.element, 'dygraph-smooth', (state.tmp.dygraph_chart_type === 'line' && NETDATA.chartLibraries.dygraph.isSparkline(state) === false)))
-            :false;
-
-        state.tmp.dygraph_include_zero = NETDATA.dataAttribute(state.element, 'dygraph-includezero', (state.tmp.dygraph_chart_type === 'stacked'));
-        var drawAxis = NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawaxis', true);
-
-        state.tmp.dygraph_options = {
-            colors:                 NETDATA.dataAttribute(state.element, 'dygraph-colors', state.chartColors()),
-
-            // leave a few pixels empty on the right of the chart
-            rightGap:               NETDATA.dataAttribute(state.element, 'dygraph-rightgap', 5),
-            showRangeSelector:      NETDATA.dataAttributeBoolean(state.element, 'dygraph-showrangeselector', false),
-            showRoller:             NETDATA.dataAttributeBoolean(state.element, 'dygraph-showroller', false),
-            title:                  NETDATA.dataAttribute(state.element, 'dygraph-title', state.title),
-            titleHeight:            NETDATA.dataAttribute(state.element, 'dygraph-titleheight', 19),
-            legend:                 NETDATA.dataAttribute(state.element, 'dygraph-legend', 'always'), // we need this to get selection events
-            labels:                 data.result.labels,
-            labelsDiv:              NETDATA.dataAttribute(state.element, 'dygraph-labelsdiv', state.element_legend_childs.hidden),
-            //labelsDivStyles:        NETDATA.dataAttribute(state.element, 'dygraph-labelsdivstyles', { 'fontSize':'1px' }),
-            //labelsDivWidth:         NETDATA.dataAttribute(state.element, 'dygraph-labelsdivwidth', state.chartWidth() - 70),
-            labelsSeparateLines:    NETDATA.dataAttributeBoolean(state.element, 'dygraph-labelsseparatelines', true),
-            labelsShowZeroValues:   (NETDATA.chartLibraries.dygraph.isLogScale(state) === true)?false:NETDATA.dataAttributeBoolean(state.element, 'dygraph-labelsshowzerovalues', true),
-            labelsKMB:              false,
-            labelsKMG2:             false,
-            showLabelsOnHighlight:  NETDATA.dataAttributeBoolean(state.element, 'dygraph-showlabelsonhighlight', true),
-            hideOverlayOnMouseOut:  NETDATA.dataAttributeBoolean(state.element, 'dygraph-hideoverlayonmouseout', true),
-            includeZero:            state.tmp.dygraph_include_zero,
-            xRangePad:              NETDATA.dataAttribute(state.element, 'dygraph-xrangepad', 0),
-            yRangePad:              NETDATA.dataAttribute(state.element, 'dygraph-yrangepad', 1),
-            valueRange:             NETDATA.dataAttribute(state.element, 'dygraph-valuerange', [ null, null ]),
-            ylabel:                 state.units_current, // (state.units_desired === 'auto')?"":state.units_current,
-            yLabelWidth:            NETDATA.dataAttribute(state.element, 'dygraph-ylabelwidth', 12),
-
-                                    // the function to plot the chart
-            plotter:                null,
-
-                                    // The width of the lines connecting data points.
-                                    // This can be used to increase the contrast or some graphs.
-            strokeWidth:            NETDATA.dataAttribute(state.element, 'dygraph-strokewidth', ((state.tmp.dygraph_chart_type === 'stacked')?0.1:((smooth === true)?1.5:0.7))),
-            strokePattern:          NETDATA.dataAttribute(state.element, 'dygraph-strokepattern', undefined),
-
-                                    // The size of the dot to draw on each point in pixels (see drawPoints).
-                                    // A dot is always drawn when a point is "isolated",
-                                    // i.e. there is a missing point on either side of it.
-                                    // This also controls the size of those dots.
-            drawPoints:             NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawpoints', false),
-
-                                    // Draw points at the edges of gaps in the data.
-                                    // This improves visibility of small data segments or other data irregularities.
-            drawGapEdgePoints:      NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawgapedgepoints', true),
-            connectSeparatedPoints: (NETDATA.chartLibraries.dygraph.isLogScale(state) === true)?false:NETDATA.dataAttributeBoolean(state.element, 'dygraph-connectseparatedpoints', false),
-            pointSize:              NETDATA.dataAttribute(state.element, 'dygraph-pointsize', 1),
-
-                                    // enabling this makes the chart with little square lines
-            stepPlot:               NETDATA.dataAttributeBoolean(state.element, 'dygraph-stepplot', false),
-
-                                    // Draw a border around graph lines to make crossing lines more easily
-                                    // distinguishable. Useful for graphs with many lines.
-            strokeBorderColor:      NETDATA.dataAttribute(state.element, 'dygraph-strokebordercolor', NETDATA.themes.current.background),
-            strokeBorderWidth:      NETDATA.dataAttribute(state.element, 'dygraph-strokeborderwidth', (state.tmp.dygraph_chart_type === 'stacked')?0.0:0.0),
-            fillGraph:              NETDATA.dataAttribute(state.element, 'dygraph-fillgraph', (state.tmp.dygraph_chart_type === 'area' || state.tmp.dygraph_chart_type === 'stacked')),
-            fillAlpha:              NETDATA.dataAttribute(state.element, 'dygraph-fillalpha',
-                                    ((state.tmp.dygraph_chart_type === 'stacked')
-                                        ?NETDATA.options.current.color_fill_opacity_stacked
-                                        :NETDATA.options.current.color_fill_opacity_area)
-                                    ),
-            stackedGraph:           NETDATA.dataAttribute(state.element, 'dygraph-stackedgraph', (state.tmp.dygraph_chart_type === 'stacked')),
-            stackedGraphNaNFill:    NETDATA.dataAttribute(state.element, 'dygraph-stackedgraphnanfill', 'none'),
-            drawAxis:               drawAxis,
-            axisLabelFontSize:      NETDATA.dataAttribute(state.element, 'dygraph-axislabelfontsize', 10),
-            axisLineColor:          NETDATA.dataAttribute(state.element, 'dygraph-axislinecolor', NETDATA.themes.current.axis),
-            axisLineWidth:          NETDATA.dataAttribute(state.element, 'dygraph-axislinewidth', 1.0),
-            drawGrid:               NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawgrid', true),
-            gridLinePattern:        NETDATA.dataAttribute(state.element, 'dygraph-gridlinepattern', null),
-            gridLineWidth:          NETDATA.dataAttribute(state.element, 'dygraph-gridlinewidth', 1.0),
-            gridLineColor:          NETDATA.dataAttribute(state.element, 'dygraph-gridlinecolor', NETDATA.themes.current.grid),
-            maxNumberWidth:         NETDATA.dataAttribute(state.element, 'dygraph-maxnumberwidth', 8),
-            sigFigs:                NETDATA.dataAttribute(state.element, 'dygraph-sigfigs', null),
-            digitsAfterDecimal:     NETDATA.dataAttribute(state.element, 'dygraph-digitsafterdecimal', 2),
-            valueFormatter:         NETDATA.dataAttribute(state.element, 'dygraph-valueformatter', undefined),
-            highlightCircleSize:    NETDATA.dataAttribute(state.element, 'dygraph-highlightcirclesize', highlightCircleSize),
-            highlightSeriesOpts:    NETDATA.dataAttribute(state.element, 'dygraph-highlightseriesopts', null), // TOO SLOW: { strokeWidth: 1.5 },
-            highlightSeriesBackgroundAlpha: NETDATA.dataAttribute(state.element, 'dygraph-highlightseriesbackgroundalpha', null), // TOO SLOW: (state.tmp.dygraph_chart_type === 'stacked')?0.7:0.5,
-            pointClickCallback:     NETDATA.dataAttribute(state.element, 'dygraph-pointclickcallback', undefined),
-            visibility:             state.dimensions_visibility.selected2BooleanArray(state.data.dimension_names),
-            logscale:               (NETDATA.chartLibraries.dygraph.isLogScale(state) === true)?'y':undefined,
-
-            axes: {
-                x: {
-                    pixelsPerLabel: NETDATA.dataAttribute(state.element, 'dygraph-xpixelsperlabel', 50),
-                    ticker: Dygraph.dateTicker,
-                    axisLabelWidth: NETDATA.dataAttribute(state.element, 'dygraph-xaxislabelwidth', 60),
-                    drawAxis: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawxaxis', drawAxis),
-                    axisLabelFormatter: function (d, gran) {
-                        void(gran);
-                        return NETDATA.dateTime.xAxisTimeString(d);
-                    }
-                },
-                y: {
-                    logscale: (NETDATA.chartLibraries.dygraph.isLogScale(state) === true)?true:undefined,
-                    pixelsPerLabel: NETDATA.dataAttribute(state.element, 'dygraph-ypixelsperlabel', 15),
-                    axisLabelWidth: NETDATA.dataAttribute(state.element, 'dygraph-yaxislabelwidth', 50),
-                    drawAxis: NETDATA.dataAttributeBoolean(state.element, 'dygraph-drawyaxis', drawAxis),
-                    axisLabelFormatter: function (y) {
-
-                        // unfortunately, we have to call this every single time
-                        state.legendFormatValueDecimalsFromMinMax(
-                            this.axes_[0].extremeRange[0],
-                            this.axes_[0].extremeRange[1]
-                        );
-
-                        var old_units = this.user_attrs_.ylabel;
-                        var v = state.legendFormatValue(y);
-                        var new_units = state.units_current;
-
-                        if(state.units_desired === 'auto' && typeof old_units !== 'undefined' && new_units !== old_units && !NETDATA.chartLibraries.dygraph.isSparkline(state)) {
-                            // console.log(this);
-                            // state.log('units discrepancy: old = ' + old_units + ', new = ' + new_units);
-                            var len = this.plugins_.length;
-                            while(len--) {
-                                // console.log(this.plugins_[len]);
-                                if(typeof this.plugins_[len].plugin.ylabel_div_ !== 'undefined'
-                                    && this.plugins_[len].plugin.ylabel_div_ !== null
-                                    && typeof this.plugins_[len].plugin.ylabel_div_.children !== 'undefined'
-                                    && this.plugins_[len].plugin.ylabel_div_.children !== null
-                                    && typeof this.plugins_[len].plugin.ylabel_div_.children[0].children !== 'undefined'
-                                    && this.plugins_[len].plugin.ylabel_div_.children[0].children !== null
-                                ) {
-                                    this.plugins_[len].plugin.ylabel_div_.children[0].children[0].innerHTML = new_units;
-                                    this.user_attrs_.ylabel = new_units;
-                                    break;
-                                }
-                            }
+            let user_element = null;
+            let user_id = NETDATA.dataAttribute(state.element, 'show-value-of-' + name.toLowerCase() + '-at', null);
+            if (user_id === null) {
+                user_id = NETDATA.dataAttribute(state.element, 'show-value-of-' + dim.toLowerCase() + '-at', null);
+            }
+            if (user_id !== null) {
+                user_element = document.getElementById(user_id) || null;
+                if (user_element === null) {
+                    state.log('Cannot find element with id: ' + user_id);
+                }
+            }
 
-                            if(len < 0)
-                                state.log('units discrepancy, but cannot find dygraphs div to change: old = ' + old_units + ', new = ' + new_units);
-                        }
+            state.element_legend_childs.series[name] = {
+                name: document.createElement('span'),
+                value: document.createElement('span'),
+                user: user_element,
+                last: null,
+                last_shown_value: null
+            };
 
-                        return v;
-                    }
-                }
-            },
-            legendFormatter: function(data) {
-                if(state.tmp.dygraph_mouse_down === true)
-                    return;
+            let label = state.element_legend_childs.series[name];
 
-                var elements = state.element_legend_childs;
-
-                // if the hidden div is not there
-                // we are not managing the legend
-                if(elements.hidden === null) return;
-
-                if (typeof data.x !== 'undefined') {
-                    state.legendSetDate(data.x);
-                    var i = data.series.length;
-                    while(i--) {
-                        var series = data.series[i];
-                        if(series.isVisible === true)
-                            state.legendSetLabelValue(series.label, series.y);
-                        else
-                            state.legendSetLabelValue(series.label, null);
-                    }
-                }
+            // create the dimension visibility tracking for this label
+            state.dimensions_visibility.dimensionAdd(name, label.name, label.value, color);
 
-                return '';
-            },
-            drawCallback: function(dygraph, is_initial) {
+            let rgb = NETDATA.colorHex2Rgb(color);
+            label.name.innerHTML = '<table class="netdata-legend-name-table-'
+                + state.chart.chart_type
+                + '" style="background-color: '
+                + 'rgba(' + rgb.r + ',' + rgb.g + ',' + rgb.b + ',' + NETDATA.options.current['color_fill_opacity_' + state.chart.chart_type] + ') !important'
+                + '"><tr class="netdata-legend-name-tr"><td class="netdata-legend-name-td"></td></tr></table>';
 
-                // the user has panned the chart and this is called to re-draw the chart
-                // 1. refresh this chart by adding data to it
-                // 2. notify all the other charts about the update they need
+            let text = document.createTextNode(' ' + name);
+            label.name.appendChild(text);
 
-                // to prevent an infinite loop (feedback), we use
-                //     state.tmp.dygraph_user_action
-                // - when true, this is initiated by a user
-                // - when false, this is feedback
+            if (count > 0) {
+                parent.appendChild(document.createElement('br'));
+            }
 
-                if(state.current.name !== 'auto' && state.tmp.dygraph_user_action === true) {
-                    state.tmp.dygraph_user_action = false;
+            parent.appendChild(label.name);
+            parent.appendChild(label.value);
+        };
 
-                    var x_range = dygraph.xAxisRange();
-                    var after = Math.round(x_range[0]);
-                    var before = Math.round(x_range[1]);
+        let content = document.createElement('div');
+
+        if (this.element_chart === null) {
+            this.element_chart = document.createElement('div');
+            this.element_chart.id = this.library_name + '-' + this.uuid + '-chart';
+            this.element.appendChild(this.element_chart);
+
+            if (this.hasLegend()) {
+                this.element_chart.className = 'netdata-chart-with-legend-right netdata-' + this.library_name + '-chart-with-legend-right';
+            } else {
+                this.element_chart.className = ' netdata-chart netdata-' + this.library_name + '-chart';
+            }
+        }
+
+        if (this.hasLegend()) {
+            if (this.element_legend === null) {
+                this.element_legend = document.createElement('div');
+                this.element_legend.className = 'netdata-chart-legend netdata-' + this.library_name + '-legend';
+                this.element.appendChild(this.element_legend);
+            } else {
+                this.element_legend.innerHTML = '';
+            }
+
+            this.element_legend_childs = {
+                content: content,
+                resize_handler: null,
+                toolbox: null,
+                toolbox_left: null,
+                toolbox_right: null,
+                toolbox_reset: null,
+                toolbox_zoomin: null,
+                toolbox_zoomout: null,
+                toolbox_volume: null,
+                title_date: document.createElement('span'),
+                title_time: document.createElement('span'),
+                title_units: document.createElement('span'),
+                perfect_scroller: document.createElement('div'),
+                series: {}
+            };
 
-                    if(NETDATA.options.debug.dygraph === true)
-                        state.log('dygraphDrawCallback(dygraph, ' + is_initial + '): mode ' + state.current.name + ' ' + (after / 1000).toString() + ' - ' + (before / 1000).toString());
-                        //console.log(state);
+            if (NETDATA.options.current.legend_toolbox && this.library.toolboxPanAndZoom !== null) {
+                this.element_legend_childs.toolbox = document.createElement('div');
+                this.element_legend_childs.toolbox_left = document.createElement('div');
+                this.element_legend_childs.toolbox_right = document.createElement('div');
+                this.element_legend_childs.toolbox_reset = document.createElement('div');
+                this.element_legend_childs.toolbox_zoomin = document.createElement('div');
+                this.element_legend_childs.toolbox_zoomout = document.createElement('div');
+                this.element_legend_childs.toolbox_volume = document.createElement('div');
+
+                const get_pan_and_zoom_step = function (event) {
+                    if (event.ctrlKey) {
+                        return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_control;
+                    } else if (event.shiftKey) {
+                        return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_shift;
+                    } else if (event.altKey) {
+                        return NETDATA.options.current.pan_and_zoom_factor * NETDATA.options.current.pan_and_zoom_factor_multiplier_alt;
+                    } else {
+                        return NETDATA.options.current.pan_and_zoom_factor;
+                    }
+                };
 
-                    if(before <= state.netdata_last && after >= state.netdata_first)
-                        // update only when we are within the data limits
-                        state.updateChartPanOrZoom(after, before);
-                }
-            },
-            zoomCallback: function(minDate, maxDate, yRanges) {
+                this.element_legend_childs.toolbox.className += ' netdata-legend-toolbox';
+                this.element.appendChild(this.element_legend_childs.toolbox);
 
-                // the user has selected a range on the chart
-                // 1. refresh this chart by adding data to it
-                // 2. notify all the other charts about the update they need
+                this.element_legend_childs.toolbox_left.className += ' netdata-legend-toolbox-button';
+                this.element_legend_childs.toolbox_left.innerHTML = NETDATA.icons.left;
+                this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_left);
+                this.element_legend_childs.toolbox_left.onclick = function (e) {
+                    e.preventDefault();
 
-                void(yRanges);
+                    let step = (that.view_before - that.view_after) * get_pan_and_zoom_step(e);
+                    let before = that.view_before - step;
+                    let after = that.view_after - step;
+                    if (after >= that.netdata_first) {
+                        that.library.toolboxPanAndZoom(that, after, before);
+                    }
+                };
+                if (NETDATA.options.current.show_help) {
+                    $(this.element_legend_childs.toolbox_left).popover({
+                        container: "body",
+                        animation: false,
+                        html: true,
+                        trigger: 'hover',
+                        placement: 'bottom',
+                        delay: {
+                            show: NETDATA.options.current.show_help_delay_show_ms,
+                            hide: NETDATA.options.current.show_help_delay_hide_ms
+                        },
+                        title: 'Pan Left',
+                        content: 'Pan the chart to the left. You can also <b>drag it</b> with your mouse or your finger (on touch devices).<br/><small>Help can be disabled from the settings.</small>'
+                    });
+                }
 
-                if(NETDATA.options.debug.dygraph === true)
-                    state.log('dygraphZoomCallback(): ' + state.current.name);
+                this.element_legend_childs.toolbox_reset.className += ' netdata-legend-toolbox-button';
+                this.element_legend_childs.toolbox_reset.innerHTML = NETDATA.icons.reset;
+                this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_reset);
+                this.element_legend_childs.toolbox_reset.onclick = function (e) {
+                    e.preventDefault();
+                    NETDATA.resetAllCharts(that);
+                };
+                if (NETDATA.options.current.show_help) {
+                    $(this.element_legend_childs.toolbox_reset).popover({
+                        container: "body",
+                        animation: false,
+                        html: true,
+                        trigger: 'hover',
+                        placement: 'bottom',
+                        delay: {
+                            show: NETDATA.options.current.show_help_delay_show_ms,
+                            hide: NETDATA.options.current.show_help_delay_hide_ms
+                        },
+                        title: 'Chart Reset',
+                        content: 'Reset all the charts to their default auto-refreshing state. You can also <b>double click</b> the chart contents with your mouse or your finger (on touch devices).<br/><small>Help can be disabled from the settings.</small>'
+                    });
+                }
 
-                NETDATA.globalSelectionSync.stop();
-                NETDATA.globalSelectionSync.delay();
-                state.setMode('zoom');
+                this.element_legend_childs.toolbox_right.className += ' netdata-legend-toolbox-button';
+                this.element_legend_childs.toolbox_right.innerHTML = NETDATA.icons.right;
+                this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_right);
+                this.element_legend_childs.toolbox_right.onclick = function (e) {
+                    e.preventDefault();
+                    let step = (that.view_before - that.view_after) * get_pan_and_zoom_step(e);
+                    let before = that.view_before + step;
+                    let after = that.view_after + step;
+                    if (before <= that.netdata_last) {
+                        that.library.toolboxPanAndZoom(that, after, before);
+                    }
+                };
+                if (NETDATA.options.current.show_help) {
+                    $(this.element_legend_childs.toolbox_right).popover({
+                        container: "body",
+                        animation: false,
+                        html: true,
+                        trigger: 'hover',
+                        placement: 'bottom',
+                        delay: {
+                            show: NETDATA.options.current.show_help_delay_show_ms,
+                            hide: NETDATA.options.current.show_help_delay_hide_ms
+                        },
+                        title: 'Pan Right',
+                        content: 'Pan the chart to the right. You can also <b>drag it</b> with your mouse or your finger (on touch devices).<br/><small>Help, can be disabled from the settings.</small>'
+                    });
+                }
 
-                // refresh it to the greatest possible zoom level
-                state.tmp.dygraph_user_action = true;
-                state.tmp.dygraph_force_zoom = true;
-                state.updateChartPanOrZoom(minDate, maxDate);
-            },
-            highlightCallback: function(event, x, points, row, seriesName) {
-                void(seriesName);
+                this.element_legend_childs.toolbox_zoomin.className += ' netdata-legend-toolbox-button';
+                this.element_legend_childs.toolbox_zoomin.innerHTML = NETDATA.icons.zoomIn;
+                this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_zoomin);
+                this.element_legend_childs.toolbox_zoomin.onclick = function (e) {
+                    e.preventDefault();
+                    let dt = ((that.view_before - that.view_after) * (get_pan_and_zoom_step(e) * 0.8) / 2);
+                    let before = that.view_before - dt;
+                    let after = that.view_after + dt;
+                    that.library.toolboxPanAndZoom(that, after, before);
+                };
+                if (NETDATA.options.current.show_help) {
+                    $(this.element_legend_childs.toolbox_zoomin).popover({
+                        container: "body",
+                        animation: false,
+                        html: true,
+                        trigger: 'hover',
+                        placement: 'bottom',
+                        delay: {
+                            show: NETDATA.options.current.show_help_delay_show_ms,
+                            hide: NETDATA.options.current.show_help_delay_hide_ms
+                        },
+                        title: 'Chart Zoom In',
+                        content: 'Zoom in the chart. You can also press SHIFT and select an area of the chart, or press SHIFT or ALT and use the mouse wheel or 2-finger touchpad scroll to zoom in or out.<br/><small>Help, can be disabled from the settings.</small>'
+                    });
+                }
 
-                state.pauseChart();
+                this.element_legend_childs.toolbox_zoomout.className += ' netdata-legend-toolbox-button';
+                this.element_legend_childs.toolbox_zoomout.innerHTML = NETDATA.icons.zoomOut;
+                this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_zoomout);
+                this.element_legend_childs.toolbox_zoomout.onclick = function (e) {
+                    e.preventDefault();
+                    let dt = (((that.view_before - that.view_after) / (1.0 - (get_pan_and_zoom_step(e) * 0.8)) - (that.view_before - that.view_after)) / 2);
+                    let before = that.view_before + dt;
+                    let after = that.view_after - dt;
 
-                // there is a bug in dygraph when the chart is zoomed enough
-                // the time it thinks is selected is wrong
-                // here we calculate the time t based on the row number selected
-                // which is ok
-                // var t = state.data_after + row * state.data_update_every;
-                // console.log('row = ' + row + ', x = ' + x + ', t = ' + t + ' ' + ((t === x)?'SAME':(Math.abs(x-t)<=state.data_update_every)?'SIMILAR':'DIFFERENT') + ', rows in db: ' + state.data_points + ' visible(x) = ' + state.timeIsVisible(x) + ' visible(t) = ' + state.timeIsVisible(t) + ' r(x) = ' + state.calculateRowForTime(x) + ' r(t) = ' + state.calculateRowForTime(t) + ' range: ' + state.data_after + ' - ' + state.data_before + ' real: ' + state.data.after + ' - ' + state.data.before + ' every: ' + state.data_update_every);
+                    that.library.toolboxPanAndZoom(that, after, before);
+                };
+                if (NETDATA.options.current.show_help) {
+                    $(this.element_legend_childs.toolbox_zoomout).popover({
+                        container: "body",
+                        animation: false,
+                        html: true,
+                        trigger: 'hover',
+                        placement: 'bottom',
+                        delay: {
+                            show: NETDATA.options.current.show_help_delay_show_ms,
+                            hide: NETDATA.options.current.show_help_delay_hide_ms
+                        },
+                        title: 'Chart Zoom Out',
+                        content: 'Zoom out the chart. You can also press SHIFT or ALT and use the mouse wheel, or 2-finger touchpad scroll to zoom in or out.<br/><small>Help, can be disabled from the settings.</small>'
+                    });
+                }
 
-                if(state.tmp.dygraph_mouse_down !== true)
-                    NETDATA.globalSelectionSync.sync(state, x);
+                //this.element_legend_childs.toolbox_volume.className += ' netdata-legend-toolbox-button';
+                //this.element_legend_childs.toolbox_volume.innerHTML = '<i class="fas fa-sort-amount-down"></i>';
+                //this.element_legend_childs.toolbox_volume.title = 'Visible Volume';
+                //this.element_legend_childs.toolbox.appendChild(this.element_legend_childs.toolbox_volume);
+                //this.element_legend_childs.toolbox_volume.onclick = function(e) {
+                //e.preventDefault();
+                //alert('clicked toolbox_volume on ' + that.id);
+                //}
+            }
 
-                // fix legend zIndex using the internal structures of dygraph legend module
-                // this works, but it is a hack!
-                // state.tmp.dygraph_instance.plugins_[0].plugin.legend_div_.style.zIndex = 10000;
-            },
-            unhighlightCallback: function(event) {
-                void(event);
+            if (NETDATA.options.current.resize_charts) {
+                this.element_legend_childs.resize_handler = document.createElement('div');
 
-                if(state.tmp.dygraph_mouse_down === true)
-                    return;
+                this.element_legend_childs.resize_handler.className += " netdata-legend-resize-handler";
+                this.element_legend_childs.resize_handler.innerHTML = NETDATA.icons.resize;
+                this.element.appendChild(this.element_legend_childs.resize_handler);
+                if (NETDATA.options.current.show_help) {
+                    $(this.element_legend_childs.resize_handler).popover({
+                        container: "body",
+                        animation: false,
+                        html: true,
+                        trigger: 'hover',
+                        placement: 'bottom',
+                        delay: {
+                            show: NETDATA.options.current.show_help_delay_show_ms,
+                            hide: NETDATA.options.current.show_help_delay_hide_ms
+                        },
+                        title: 'Chart Resize',
+                        content: 'Drag this point with your mouse or your finger (on touch devices), to resize the chart vertically. You can also <b>double click it</b> or <b>double tap it</b> to reset between 2 states: the default and the one that fits all the values.<br/><small>Help, can be disabled from the settings.</small>'
+                    });
+                }
 
-                if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                    state.log('dygraphUnhighlightCallback()');
+                // mousedown event
+                this.element_legend_childs.resize_handler.onmousedown =
+                    function (e) {
+                        that.resizeHandler(e);
+                    };
 
-                state.unpauseChart();
-                NETDATA.globalSelectionSync.stop();
-            },
-            underlayCallback: function(canvas, area, g) {
+                // touchstart event
+                this.element_legend_childs.resize_handler.addEventListener('touchstart', function (e) {
+                    that.resizeHandler(e);
+                }, false);
+            }
 
-                // the chart is about to be drawn
-                // this function renders global highlighted time-frame
+            if (this.chart) {
+                this.element_legend_childs.title_date.title = this.legendPluginModuleString(true);
+                this.element_legend_childs.title_time.title = this.legendResolutionTooltip();
+            }
 
-                if(NETDATA.globalChartUnderlay.isActive()) {
-                    var after = NETDATA.globalChartUnderlay.after;
-                    var before = NETDATA.globalChartUnderlay.before;
+            this.element_legend_childs.title_date.className += " netdata-legend-title-date";
+            this.element_legend.appendChild(this.element_legend_childs.title_date);
+            this.tmp.__last_shown_legend_date = undefined;
 
-                    if(after < state.view_after)
-                        after = state.view_after;
+            this.element_legend.appendChild(document.createElement('br'));
 
-                    if(before > state.view_before)
-                        before = state.view_before;
+            this.element_legend_childs.title_time.className += " netdata-legend-title-time";
+            this.element_legend.appendChild(this.element_legend_childs.title_time);
+            this.tmp.__last_shown_legend_time = undefined;
 
-                    if(after < before) {
-                        var bottom_left = g.toDomCoords(after, -20);
-                        var top_right = g.toDomCoords(before, +20);
+            this.element_legend.appendChild(document.createElement('br'));
 
-                        var left = bottom_left[0];
-                        var right = top_right[0];
+            this.element_legend_childs.title_units.className += " netdata-legend-title-units";
+            this.element_legend_childs.title_units.innerText = this.units_current;
+            this.element_legend.appendChild(this.element_legend_childs.title_units);
+            this.tmp.__last_shown_legend_units = undefined;
 
-                        canvas.fillStyle = NETDATA.themes.current.highlight;
-                        canvas.fillRect(left, area.y, right - left, area.h);
-                    }
-                }
-            },
-            interactionModel : {
-                mousedown: function(event, dygraph, context) {
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.mousedown()');
+            this.element_legend.appendChild(document.createElement('br'));
 
-                    state.tmp.dygraph_user_action = true;
+            this.element_legend_childs.perfect_scroller.className = 'netdata-legend-series';
+            this.element_legend.appendChild(this.element_legend_childs.perfect_scroller);
 
-                    if(NETDATA.options.debug.dygraph === true)
-                        state.log('dygraphMouseDown()');
+            content.className = 'netdata-legend-series-content';
+            this.element_legend_childs.perfect_scroller.appendChild(content);
 
-                    // Right-click should not initiate anything.
-                    if(event.button && event.button === 2) return;
+            this.element_legend_childs.content = content;
 
-                    NETDATA.globalSelectionSync.stop();
-                    NETDATA.globalSelectionSync.delay();
+            if (NETDATA.options.current.show_help) {
+                $(content).popover({
+                    container: "body",
+                    animation: false,
+                    html: true,
+                    trigger: 'hover',
+                    placement: 'bottom',
+                    title: 'Chart Legend',
+                    delay: {
+                        show: NETDATA.options.current.show_help_delay_show_ms,
+                        hide: NETDATA.options.current.show_help_delay_hide_ms
+                    },
+                    content: 'You can click or tap on the values or the labels to select dimensions. By pressing SHIFT or CONTROL, you can enable or disable multiple dimensions.<br/><small>Help, can be disabled from the settings.</small>'
+                });
+            }
+        } else {
+            this.element_legend_childs = {
+                content: content,
+                resize_handler: null,
+                toolbox: null,
+                toolbox_left: null,
+                toolbox_right: null,
+                toolbox_reset: null,
+                toolbox_zoomin: null,
+                toolbox_zoomout: null,
+                toolbox_volume: null,
+                title_date: null,
+                title_time: null,
+                title_units: null,
+                perfect_scroller: null,
+                series: {}
+            };
+        }
 
-                    state.tmp.dygraph_mouse_down = true;
-                    context.initializeMouseDown(event, dygraph, context);
+        if (this.data) {
+            this.element_legend_childs.series.labels_key = this.data.dimension_names.toString();
+            if (this.debug) {
+                this.log('labels from data: "' + this.element_legend_childs.series.labels_key + '"');
+            }
 
-                    //console.log(event);
-                    if(event.button && event.button === 1) {
-                        if (event.shiftKey) {
-                            //console.log('middle mouse button dragging (PAN)');
+            for (let i = 0, len = this.data.dimension_names.length; i < len; i++) {
+                genLabel(this, content, this.data.dimension_ids[i], this.data.dimension_names[i], i);
+            }
+        } else {
+            let tmp = [];
+            keys = Object.keys(this.chart.dimensions);
+            for (let i = 0, len = keys.length; i < len; i++) {
+                dim = keys[i];
+                tmp.push(this.chart.dimensions[dim].name);
+                genLabel(this, content, dim, this.chart.dimensions[dim].name, i);
+            }
+            this.element_legend_childs.series.labels_key = tmp.toString();
+            if (this.debug) {
+                this.log('labels from chart: "' + this.element_legend_childs.series.labels_key + '"');
+            }
+        }
 
-                            state.setMode('pan');
-                            // NETDATA.globalSelectionSync.delay();
-                            state.tmp.dygraph_highlight_after = null;
-                            Dygraph.startPan(event, dygraph, context);
-                        }
-                        else if(event.altKey || event.ctrlKey || event.metaKey) {
-                            //console.log('middle mouse button highlight');
+        // create a hidden div to be used for hidding
+        // the original legend of the chart library
+        let el = document.createElement('div');
+        if (this.element_legend !== null) {
+            this.element_legend.appendChild(el);
+        }
+        el.style.display = 'none';
 
-                            if (!(event.offsetX && event.offsetY)) {
-                                event.offsetX = event.layerX - event.target.offsetLeft;
-                                event.offsetY = event.layerY - event.target.offsetTop;
-                            }
-                            state.tmp.dygraph_highlight_after = dygraph.toDataXCoord(event.offsetX);
-                            Dygraph.startZoom(event, dygraph, context);
-                        }
-                        else {
-                            //console.log('middle mouse button selection for zoom (ZOOM)');
+        this.element_legend_childs.hidden = document.createElement('div');
+        el.appendChild(this.element_legend_childs.hidden);
 
-                            state.setMode('zoom');
-                            // NETDATA.globalSelectionSync.delay();
-                            state.tmp.dygraph_highlight_after = null;
-                            Dygraph.startZoom(event, dygraph, context);
-                        }
-                    }
-                    else {
-                        if (event.shiftKey) {
-                            //console.log('left mouse button selection for zoom (ZOOM)');
+        if (this.element_legend_childs.perfect_scroller !== null) {
+            Ps.initialize(this.element_legend_childs.perfect_scroller, {
+                wheelSpeed: 0.2,
+                wheelPropagation: true,
+                swipePropagation: true,
+                minScrollbarLength: null,
+                maxScrollbarLength: null,
+                useBothWheelAxes: false,
+                suppressScrollX: true,
+                suppressScrollY: false,
+                scrollXMarginOffset: 0,
+                scrollYMarginOffset: 0,
+                theme: 'default'
+            });
+            Ps.update(this.element_legend_childs.perfect_scroller);
+        }
 
-                            state.setMode('zoom');
-                            // NETDATA.globalSelectionSync.delay();
-                            state.tmp.dygraph_highlight_after = null;
-                            Dygraph.startZoom(event, dygraph, context);
-                        }
-                        else if(event.altKey || event.ctrlKey || event.metaKey) {
-                            //console.log('left mouse button highlight');
+        this.legendShowLatestValues();
+    };
 
-                            if (!(event.offsetX && event.offsetY)) {
-                                event.offsetX = event.layerX - event.target.offsetLeft;
-                                event.offsetY = event.layerY - event.target.offsetTop;
-                            }
-                            state.tmp.dygraph_highlight_after = dygraph.toDataXCoord(event.offsetX);
-                            Dygraph.startZoom(event, dygraph, context);
-                        }
-                        else {
-                            //console.log('left mouse button dragging (PAN)');
+    this.hasLegend = function () {
+        if (typeof this.tmp.___hasLegendCache___ !== 'undefined') {
+            return this.tmp.___hasLegendCache___;
+        }
 
-                            state.setMode('pan');
-                            // NETDATA.globalSelectionSync.delay();
-                            state.tmp.dygraph_highlight_after = null;
-                            Dygraph.startPan(event, dygraph, context);
-                        }
-                    }
-                },
-                mousemove: function(event, dygraph, context) {
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.mousemove()');
+        let leg = false;
+        if (this.library && this.library.legend(this) === 'right-side') {
+            leg = true;
+        }
 
-                    if(state.tmp.dygraph_highlight_after !== null) {
-                        //console.log('highlight selection...');
+        this.tmp.___hasLegendCache___ = leg;
+        return leg;
+    };
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+    this.legendWidth = function () {
+        return (this.hasLegend()) ? 140 : 0;
+    };
 
-                        state.tmp.dygraph_user_action = true;
-                        Dygraph.moveZoom(event, dygraph, context);
-                        event.preventDefault();
-                    }
-                    else if(context.isPanning) {
-                        //console.log('panning...');
+    this.legendHeight = function () {
+        return $(this.element).height();
+    };
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+    this.chartWidth = function () {
+        return $(this.element).width() - this.legendWidth();
+    };
 
-                        state.tmp.dygraph_user_action = true;
-                        //NETDATA.globalSelectionSync.stop();
-                        //NETDATA.globalSelectionSync.delay();
-                        state.setMode('pan');
-                        context.is2DPan = false;
-                        Dygraph.movePan(event, dygraph, context);
-                    }
-                    else if(context.isZooming) {
-                        //console.log('zooming...');
+    this.chartHeight = function () {
+        return $(this.element).height();
+    };
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+    this.chartPixelsPerPoint = function () {
+        // force an options provided detail
+        let px = this.pixels_per_point;
 
-                        state.tmp.dygraph_user_action = true;
-                        //NETDATA.globalSelectionSync.stop();
-                        //NETDATA.globalSelectionSync.delay();
-                        state.setMode('zoom');
-                        Dygraph.moveZoom(event, dygraph, context);
-                    }
-                },
-                mouseup: function(event, dygraph, context) {
-                    state.tmp.dygraph_mouse_down = false;
+        if (this.library && px < this.library.pixels_per_point(this)) {
+            px = this.library.pixels_per_point(this);
+        }
 
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.mouseup()');
+        if (px < NETDATA.options.current.pixels_per_point) {
+            px = NETDATA.options.current.pixels_per_point;
+        }
 
-                    if(state.tmp.dygraph_highlight_after !== null) {
-                        //console.log('done highlight selection');
+        return px;
+    };
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+    this.needsRecreation = function () {
+        let ret = (
+            this.chart_created &&
+            this.library &&
+            this.library.autoresize() === false &&
+            this.tm.last_resized < NETDATA.options.last_page_resize
+        );
 
-                        if (!(event.offsetX && event.offsetY)){
-                            event.offsetX = event.layerX - event.target.offsetLeft;
-                            event.offsetY = event.layerY - event.target.offsetTop;
-                        }
+        if (this.debug) {
+            this.log('needsRecreation(): ' + ret.toString() + ', chart_created = ' + this.chart_created.toString());
+        }
 
-                        NETDATA.globalChartUnderlay.set(state
-                            , state.tmp.dygraph_highlight_after
-                            , dygraph.toDataXCoord(event.offsetX)
-                            , state.view_after
-                            , state.view_before
-                        );
+        return ret;
+    };
 
-                        state.tmp.dygraph_highlight_after = null;
+    this.chartDataUniqueID = function () {
+        return this.id + ',' + this.library_name + ',' + this.dimensions + ',' + this.chartURLOptions();
+    };
 
-                        context.isZooming = false;
-                        dygraph.clearZoomRect_();
-                        dygraph.drawGraph_(false);
+    this.chartURLOptions = function () {
+        let ret = '';
 
-                        // refresh all the charts immediately
-                        NETDATA.options.auto_refresher_stop_until = 0;
-                    }
-                    else if (context.isPanning) {
-                        //console.log('done panning');
+        if (this.override_options !== null) {
+            ret = this.override_options.toString();
+        } else {
+            ret = this.library.options(this);
+        }
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+        if (this.append_options !== null) {
+            ret += '%7C' + this.append_options.toString();
+        }
 
-                        state.tmp.dygraph_user_action = true;
-                        Dygraph.endPan(event, dygraph, context);
+        ret += '%7C' + 'jsonwrap';
 
-                        // refresh all the charts immediately
-                        NETDATA.options.auto_refresher_stop_until = 0;
-                    }
-                    else if (context.isZooming) {
-                        //console.log('done zomming');
+        if (NETDATA.options.current.eliminate_zero_dimensions) {
+            ret += '%7C' + 'nonzero';
+        }
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+        return ret;
+    };
 
-                        state.tmp.dygraph_user_action = true;
-                        Dygraph.endZoom(event, dygraph, context);
+    this.chartURL = function () {
+        let after, before, points_multiplier = 1;
+        if (NETDATA.globalPanAndZoom.isActive()) {
+            if (this.current.force_before_ms !== null && this.current.force_after_ms !== null) {
+                this.tm.pan_and_zoom_seq = 0;
 
-                        // refresh all the charts immediately
-                        NETDATA.options.auto_refresher_stop_until = 0;
-                    }
-                },
-                click: function(event, dygraph, context) {
-                    void(dygraph);
-                    void(context);
+                before = Math.round(this.current.force_before_ms / 1000);
+                after = Math.round(this.current.force_after_ms / 1000);
+                this.view_after = after * 1000;
+                this.view_before = before * 1000;
 
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.click()');
+                if (NETDATA.options.current.pan_and_zoom_data_padding) {
+                    this.requested_padding = Math.round((before - after) / 2);
+                    after -= this.requested_padding;
+                    before += this.requested_padding;
+                    this.requested_padding *= 1000;
+                    points_multiplier = 2;
+                }
 
-                    event.preventDefault();
-                },
-                dblclick: function(event, dygraph, context) {
-                    void(event);
-                    void(dygraph);
-                    void(context);
-
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.dblclick()');
-                    NETDATA.resetAllCharts(state);
-                },
-                wheel: function(event, dygraph, context) {
-                    void(context);
-
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.wheel()');
-
-                    // Take the offset of a mouse event on the dygraph canvas and
-                    // convert it to a pair of percentages from the bottom left.
-                    // (Not top left, bottom is where the lower value is.)
-                    function offsetToPercentage(g, offsetX, offsetY) {
-                        // This is calculating the pixel offset of the leftmost date.
-                        var xOffset = g.toDomCoords(g.xAxisRange()[0], null)[0];
-                        var yar0 = g.yAxisRange(0);
-
-                        // This is calculating the pixel of the highest value. (Top pixel)
-                        var yOffset = g.toDomCoords(null, yar0[1])[1];
-
-                        // x y w and h are relative to the corner of the drawing area,
-                        // so that the upper corner of the drawing area is (0, 0).
-                        var x = offsetX - xOffset;
-                        var y = offsetY - yOffset;
-
-                        // This is computing the rightmost pixel, effectively defining the
-                        // width.
-                        var w = g.toDomCoords(g.xAxisRange()[1], null)[0] - xOffset;
-
-                        // This is computing the lowest pixel, effectively defining the height.
-                        var h = g.toDomCoords(null, yar0[0])[1] - yOffset;
-
-                        // Percentage from the left.
-                        var xPct = w === 0 ? 0 : (x / w);
-                        // Percentage from the top.
-                        var yPct = h === 0 ? 0 : (y / h);
-
-                        // The (1-) part below changes it from "% distance down from the top"
-                        // to "% distance up from the bottom".
-                        return [xPct, (1-yPct)];
-                    }
+                this.current.force_before_ms = null;
+                this.current.force_after_ms = null;
+            } else {
+                this.tm.pan_and_zoom_seq = NETDATA.globalPanAndZoom.seq;
 
-                    // Adjusts [x, y] toward each other by zoomInPercentage%
-                    // Split it so the left/bottom axis gets xBias/yBias of that change and
-                    // tight/top gets (1-xBias)/(1-yBias) of that change.
-                    //
-                    // If a bias is missing it splits it down the middle.
-                    function zoomRange(g, zoomInPercentage, xBias, yBias) {
-                        xBias = xBias || 0.5;
-                        yBias = yBias || 0.5;
-
-                        function adjustAxis(axis, zoomInPercentage, bias) {
-                            var delta = axis[1] - axis[0];
-                            var increment = delta * zoomInPercentage;
-                            var foo = [increment * bias, increment * (1-bias)];
-
-                            return [ axis[0] + foo[0], axis[1] - foo[1] ];
-                        }
+                after = Math.round(NETDATA.globalPanAndZoom.force_after_ms / 1000);
+                before = Math.round(NETDATA.globalPanAndZoom.force_before_ms / 1000);
+                this.view_after = after * 1000;
+                this.view_before = before * 1000;
 
-                        var yAxes = g.yAxisRanges();
-                        var newYAxes = [];
-                        for (var i = 0; i < yAxes.length; i++) {
-                            newYAxes[i] = adjustAxis(yAxes[i], zoomInPercentage, yBias);
-                        }
+                this.requested_padding = null;
+                points_multiplier = 1;
+            }
+        } else {
+            this.tm.pan_and_zoom_seq = 0;
 
-                        return adjustAxis(g.xAxisRange(), zoomInPercentage, xBias);
-                    }
+            before = this.before;
+            after = this.after;
+            this.view_after = after * 1000;
+            this.view_before = before * 1000;
 
-                    if(event.altKey || event.shiftKey) {
-                        state.tmp.dygraph_user_action = true;
+            this.requested_padding = null;
+            points_multiplier = 1;
+        }
 
-                        NETDATA.globalSelectionSync.stop();
-                        NETDATA.globalSelectionSync.delay();
+        this.requested_after = after * 1000;
+        this.requested_before = before * 1000;
 
-                        // http://dygraphs.com/gallery/interaction-api.js
-                        var normal_def;
-                        if(typeof event.wheelDelta === 'number' && !isNaN(event.wheelDelta))
-                            // chrome
-                            normal_def = event.wheelDelta / 40;
-                        else
-                            // firefox
-                            normal_def = event.deltaY * -1.2;
+        let data_points;
+        if (NETDATA.options.force_data_points !== 0) {
+            data_points = NETDATA.options.force_data_points;
+            this.data_points = data_points;
+        } else {
+            this.data_points = this.points || Math.round(this.chartWidth() / this.chartPixelsPerPoint());
+            data_points = this.data_points * points_multiplier;
+        }
 
-                        var normal = (event.detail) ? event.detail * -1 : normal_def;
-                        var percentage = normal / 50;
+        // build the data URL
+        this.data_url = this.host + this.chart.data_url;
+        this.data_url += "&format=" + this.library.format();
+        this.data_url += "&points=" + (data_points).toString();
+        this.data_url += "&group=" + this.method;
+        this.data_url += "&gtime=" + this.gtime;
+        this.data_url += "&options=" + this.chartURLOptions();
 
-                        if (!(event.offsetX && event.offsetY)){
-                            event.offsetX = event.layerX - event.target.offsetLeft;
-                            event.offsetY = event.layerY - event.target.offsetTop;
-                        }
+        if (after) {
+            this.data_url += "&after=" + after.toString();
+        }
 
-                        var percentages = offsetToPercentage(dygraph, event.offsetX, event.offsetY);
-                        var xPct = percentages[0];
-                        var yPct = percentages[1];
+        if (before) {
+            this.data_url += "&before=" + before.toString();
+        }
 
-                        var new_x_range = zoomRange(dygraph, percentage, xPct, yPct);
-                        var after = new_x_range[0];
-                        var before = new_x_range[1];
+        if (this.dimensions) {
+            this.data_url += "&dimensions=" + this.dimensions;
+        }
 
-                        var first = state.netdata_first + state.data_update_every;
-                        var last = state.netdata_last + state.data_update_every;
+        if (NETDATA.options.debug.chart_data_url || this.debug) {
+            this.log('chartURL(): ' + this.data_url + ' WxH:' + this.chartWidth() + 'x' + this.chartHeight() + ' points: ' + data_points.toString() + ' library: ' + this.library_name);
+        }
+    };
 
-                        if(before > last) {
-                            after -= (before - last);
-                            before = last;
-                        }
-                        if(after < first) {
-                            after = first;
-                        }
+    this.redrawChart = function () {
+        if (this.data !== null) {
+            this.updateChartWithData(this.data);
+        }
+    };
 
-                        state.setMode('zoom');
-                        state.updateChartPanOrZoom(after, before, function() {
-                            dygraph.updateOptions({ dateWindow: [ after, before ] });
-                        });
+    this.updateChartWithData = function (data) {
+        if (this.debug) {
+            this.log('updateChartWithData() called.');
+        }
 
-                        event.preventDefault();
-                    }
-                },
-                touchstart: function(event, dygraph, context) {
-                    state.tmp.dygraph_mouse_down = true;
+        // this may force the chart to be re-created
+        resizeChart();
 
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.touchstart()');
+        this.data = data;
 
-                    state.tmp.dygraph_user_action = true;
-                    state.setMode('zoom');
-                    state.pauseChart();
+        let started = Date.now();
+        let view_update_every = data.view_update_every * 1000;
 
-                    NETDATA.globalSelectionSync.stop();
-                    NETDATA.globalSelectionSync.delay();
+        if (this.data_update_every !== view_update_every) {
+            if (this.element_legend_childs.title_time) {
+                this.element_legend_childs.title_time.title = this.legendResolutionTooltip();
+            }
+        }
 
-                    Dygraph.defaultInteractionModel.touchstart(event, dygraph, context);
+        // if the result is JSON, find the latest update-every
+        this.data_update_every = view_update_every;
+        this.data_after = data.after * 1000;
+        this.data_before = data.before * 1000;
+        this.netdata_first = data.first_entry * 1000;
+        this.netdata_last = data.last_entry * 1000;
+        this.data_points = data.points;
 
-                    // we overwrite the touch directions at the end, to overwrite
-                    // the internal default of dygraph
-                    context.touchDirections = { x: true, y: false };
+        data.state = this;
 
-                    state.dygraph_last_touch_start = Date.now();
-                    state.dygraph_last_touch_move = 0;
+        if (NETDATA.options.current.pan_and_zoom_data_padding && this.requested_padding !== null) {
+            if (this.view_after < this.data_after) {
+                // console.log('adjusting view_after from ' + this.view_after + ' to ' + this.data_after);
+                this.view_after = this.data_after;
+            }
 
-                    if(typeof event.touches[0].pageX === 'number')
-                        state.dygraph_last_touch_page_x = event.touches[0].pageX;
-                    else
-                        state.dygraph_last_touch_page_x = 0;
-                },
-                touchmove: function(event, dygraph, context) {
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.touchmove()');
+            if (this.view_before > this.data_before) {
+                // console.log('adjusting view_before from ' + this.view_before + ' to ' + this.data_before);
+                this.view_before = this.data_before;
+            }
+        } else {
+            this.view_after = this.data_after;
+            this.view_before = this.data_before;
+        }
 
-                    NETDATA.globalSelectionSync.stop();
-                    NETDATA.globalSelectionSync.delay();
+        if (this.debug) {
+            this.log('UPDATE No ' + this.updates_counter + ' COMPLETED');
 
-                    state.tmp.dygraph_user_action = true;
-                    Dygraph.defaultInteractionModel.touchmove(event, dygraph, context);
+            if (this.current.force_after_ms) {
+                this.log('STATUS: forced    : ' + (this.current.force_after_ms / 1000).toString() + ' - ' + (this.current.force_before_ms / 1000).toString());
+            } else {
+                this.log('STATUS: forced    : unset');
+            }
 
-                    state.dygraph_last_touch_move = Date.now();
-                },
-                touchend: function(event, dygraph, context) {
-                    state.tmp.dygraph_mouse_down = false;
+            this.log('STATUS: requested : ' + (this.requested_after / 1000).toString() + ' - ' + (this.requested_before / 1000).toString());
+            this.log('STATUS: downloaded: ' + (this.data_after / 1000).toString() + ' - ' + (this.data_before / 1000).toString());
+            this.log('STATUS: rendered  : ' + (this.view_after / 1000).toString() + ' - ' + (this.view_before / 1000).toString());
+            this.log('STATUS: points    : ' + (this.data_points).toString());
+        }
 
-                    if(NETDATA.options.debug.dygraph === true || state.debug === true)
-                        state.log('interactionModel.touchend()');
+        if (this.data_points === 0) {
+            noDataToShow();
+            return;
+        }
 
-                    NETDATA.globalSelectionSync.stop();
-                    NETDATA.globalSelectionSync.delay();
+        if (this.updates_since_last_creation >= this.library.max_updates_to_recreate()) {
+            if (this.debug) {
+                this.log('max updates of ' + this.updates_since_last_creation.toString() + ' reached. Forcing re-generation.');
+            }
 
-                    state.tmp.dygraph_user_action = true;
-                    Dygraph.defaultInteractionModel.touchend(event, dygraph, context);
+            init('force');
+            return;
+        }
 
-                    // if it didn't move, it is a selection
-                    if(state.dygraph_last_touch_move === 0 && state.dygraph_last_touch_page_x !== 0) {
-                        NETDATA.globalSelectionSync.dont_sync_before = 0;
-                        NETDATA.globalSelectionSync.setMaster(state);
+        // check and update the legend
+        this.legendUpdateDOM();
 
-                        // internal api of dygraph
-                        var pct = (state.dygraph_last_touch_page_x - (dygraph.plotter_.area.x + state.element.getBoundingClientRect().left)) / dygraph.plotter_.area.w;
-                        console.log('pct: ' + pct.toString());
+        if (this.chart_created && typeof this.library.update === 'function') {
+            if (this.debug) {
+                this.log('updating chart...');
+            }
 
-                        var t = Math.round(state.view_after + (state.view_before - state.view_after) * pct);
-                        if(NETDATA.dygraphSetSelection(state, t) === true) {
-                            NETDATA.globalSelectionSync.sync(state, t);
-                        }
-                    }
+            if (!callChartLibraryUpdateSafely(data)) {
+                return;
+            }
+        } else {
+            if (this.debug) {
+                this.log('creating chart...');
+            }
 
-                    // if it was double tap within double click time, reset the charts
-                    var now = Date.now();
-                    if(typeof state.dygraph_last_touch_end !== 'undefined') {
-                        if(state.dygraph_last_touch_move === 0) {
-                            var dt = now - state.dygraph_last_touch_end;
-                            if(dt <= NETDATA.options.current.double_click_speed)
-                                NETDATA.resetAllCharts(state);
-                        }
-                    }
+            if (!callChartLibraryCreateSafely(data)) {
+                return;
+            }
+        }
 
-                    // remember the timestamp of the last touch end
-                    state.dygraph_last_touch_end = now;
+        if (this.isVisible()) {
+            hideMessage();
+            this.legendShowLatestValues();
+        } else {
+            this.__redraw_on_unhide = true;
 
-                    // refresh all the charts immediately
-                    NETDATA.options.auto_refresher_stop_until = 0;
-                }
+            if (this.debug) {
+                this.log("drawn while not visible");
             }
-        };
+        }
 
-        if(NETDATA.chartLibraries.dygraph.isLogScale(state) === true) {
-            if(Array.isArray(state.tmp.dygraph_options.valueRange) && state.tmp.dygraph_options.valueRange[0] <= 0)
-                state.tmp.dygraph_options.valueRange[0] = null;
+        if (this.selected) {
+            NETDATA.globalSelectionSync.stop();
         }
 
-        if(NETDATA.chartLibraries.dygraph.isSparkline(state) === true) {
-            state.tmp.dygraph_options.drawGrid = false;
-            state.tmp.dygraph_options.drawAxis = false;
-            state.tmp.dygraph_options.title = undefined;
-            state.tmp.dygraph_options.ylabel = undefined;
-            state.tmp.dygraph_options.yLabelWidth = 0;
-            //state.tmp.dygraph_options.labelsDivWidth = 120;
-            //state.tmp.dygraph_options.labelsDivStyles.width = '120px';
-            state.tmp.dygraph_options.labelsSeparateLines = true;
-            state.tmp.dygraph_options.rightGap = 0;
-            state.tmp.dygraph_options.yRangePad = 1;
-            state.tmp.dygraph_options.axes.x.drawAxis = false;
-            state.tmp.dygraph_options.axes.y.drawAxis = false;
+        // update the performance counters
+        let now = Date.now();
+        this.tm.last_updated = now;
+
+        // don't update last_autorefreshed if this chart is
+        // forced to be updated with global PanAndZoom
+        if (NETDATA.globalPanAndZoom.isActive()) {
+            this.tm.last_autorefreshed = 0;
+        } else {
+            if (NETDATA.options.current.parallel_refresher && NETDATA.options.current.concurrent_refreshes && typeof this.force_update_every !== 'number') {
+                this.tm.last_autorefreshed = now - (now % this.data_update_every);
+            } else {
+                this.tm.last_autorefreshed = now;
+            }
         }
 
-        if(smooth === true) {
-            state.tmp.dygraph_smooth_eligible = true;
+        this.refresh_dt_ms = now - started;
+        NETDATA.options.auto_refresher_fast_weight += this.refresh_dt_ms;
 
-            if(NETDATA.options.current.smooth_plot === true)
-                state.tmp.dygraph_options.plotter = smoothPlotter;
+        if (this.refresh_dt_element !== null) {
+            this.refresh_dt_element.innerText = this.refresh_dt_ms.toString();
         }
-        else state.tmp.dygraph_smooth_eligible = false;
 
-        if(netdataSnapshotData !== null && NETDATA.globalPanAndZoom.isActive() === true && NETDATA.globalPanAndZoom.isMaster(state) === false) {
-            // pan and zoom on snapshots
-            state.tmp.dygraph_options.dateWindow = [ NETDATA.globalPanAndZoom.force_after_ms, NETDATA.globalPanAndZoom.force_before_ms ];
-            //state.tmp.dygraph_options.isZoomedIgnoreProgrammaticZoom = true;
+        if (this.foreign_element_before !== null) {
+            this.foreign_element_before.innerText = NETDATA.dateTime.localeDateString(this.view_before) + ' ' + NETDATA.dateTime.localeTimeString(this.view_before);
         }
 
-        state.tmp.dygraph_instance = new Dygraph(state.element_chart,
-            data.result.data, state.tmp.dygraph_options);
+        if (this.foreign_element_after !== null) {
+            this.foreign_element_after.innerText = NETDATA.dateTime.localeDateString(this.view_after) + ' ' + NETDATA.dateTime.localeTimeString(this.view_after);
+        }
 
-        state.tmp.dygraph_force_zoom = false;
-        state.tmp.dygraph_user_action = false;
-        state.tmp.dygraph_last_rendered = Date.now();
-        state.tmp.dygraph_highlight_after = null;
+        if (this.foreign_element_duration !== null) {
+            this.foreign_element_duration.innerText = NETDATA.seconds4human(Math.floor((this.view_before - this.view_after) / 1000) + 1);
+        }
 
-        if(state.tmp.dygraph_options.valueRange[0] === null && state.tmp.dygraph_options.valueRange[1] === null) {
-            if (typeof state.tmp.dygraph_instance.axes_[0].extremeRange !== 'undefined') {
-                state.tmp.__commonMin = NETDATA.dataAttribute(state.element, 'common-min', null);
-                state.tmp.__commonMax = NETDATA.dataAttribute(state.element, 'common-max', null);
-            }
-            else {
-                state.log('incompatible version of Dygraph detected');
-                state.tmp.__commonMin = null;
-                state.tmp.__commonMax = null;
-            }
+        if (this.foreign_element_update_every !== null) {
+            this.foreign_element_update_every.innerText = NETDATA.seconds4human(Math.floor(this.data_update_every / 1000));
         }
-        else {
-            // if the user gave a valueRange, respect it
-            state.tmp.__commonMin = null;
-            state.tmp.__commonMax = null;
+    };
+
+    this.getSnapshotData = function (key) {
+        if (this.debug) {
+            this.log('updating from snapshot: ' + key);
         }
 
-        return true;
-    };
+        if (typeof netdataSnapshotData.data[key] === 'undefined') {
+            this.log('snapshot does not include data for key "' + key + '"');
+            return null;
+        }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // morris
+        if (typeof netdataSnapshotData.data[key] !== 'string') {
+            this.log('snapshot data for key "' + key + '" is not string');
+            return null;
+        }
 
-    NETDATA.morrisInitialize = function(callback) {
-        if(typeof netdataNoMorris === 'undefined' || !netdataNoMorris) {
+        let uncompressed;
+        try {
+            uncompressed = netdataSnapshotData.uncompress(netdataSnapshotData.data[key]);
 
-            // morris requires raphael
-            if(!NETDATA.chartLibraries.raphael.initialized) {
-                if(NETDATA.chartLibraries.raphael.enabled) {
-                    NETDATA.raphaelInitialize(function() {
-                        NETDATA.morrisInitialize(callback);
-                    });
-                }
-                else {
-                    NETDATA.chartLibraries.morris.enabled = false;
-                    if(typeof callback === "function")
-                        return callback();
-                }
+            if (uncompressed === null) {
+                this.log('uncompressed snapshot data for key ' + key + ' is null');
+                return null;
             }
-            else {
-                NETDATA._loadCSS(NETDATA.morris_css);
 
-                $.ajax({
-                    url: NETDATA.morris_js,
-                    cache: true,
-                    dataType: "script",
-                    xhrFields: { withCredentials: true } // required for the cookie
-                })
-                .done(function() {
-                    NETDATA.registerChartLibrary('morris', NETDATA.morris_js);
-                })
-                .fail(function() {
-                    NETDATA.chartLibraries.morris.enabled = false;
-                    NETDATA.error(100, NETDATA.morris_js);
-                })
-                .always(function() {
-                    if(typeof callback === "function")
-                        return callback();
-                });
+            if (typeof uncompressed === 'undefined') {
+                this.log('uncompressed snapshot data for key ' + key + ' is undefined');
+                return null;
             }
+        } catch (e) {
+            this.log('decompression of snapshot data for key ' + key + ' failed');
+            console.log(e);
+            uncompressed = null;
         }
-        else {
-            NETDATA.chartLibraries.morris.enabled = false;
-            if(typeof callback === "function")
-                return callback();
-        }
-    };
 
-    NETDATA.morrisChartUpdate = function(state, data) {
-        state.morris_instance.setData(data.result.data);
-        return true;
-    };
-
-    NETDATA.morrisChartCreate = function(state, data) {
-
-        state.morris_options = {
-                element: state.element_chart.id,
-                data: data.result.data,
-                xkey: 'time',
-                ykeys: data.dimension_names,
-                labels: data.dimension_names,
-                lineWidth: 2,
-                pointSize: 3,
-                smooth: true,
-                hideHover: 'auto',
-                parseTime: true,
-                continuousLine: false,
-                behaveLikeLine: false
-        };
-
-        if(state.chart.chart_type === 'line')
-            state.morris_instance = new Morris.Line(state.morris_options);
+        if (typeof uncompressed !== 'string') {
+            this.log('uncompressed snapshot data for key ' + key + ' is not string');
+            return null;
+        }
 
-        else if(state.chart.chart_type === 'area') {
-            state.morris_options.behaveLikeLine = true;
-            state.morris_instance = new Morris.Area(state.morris_options);
+        let data;
+        try {
+            data = JSON.parse(uncompressed);
+        } catch (e) {
+            this.log('parsing snapshot data for key ' + key + ' failed');
+            console.log(e);
+            data = null;
         }
-        else // stacked
-            state.morris_instance = new Morris.Area(state.morris_options);
 
-        return true;
+        return data;
     };
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // raphael
-
-    NETDATA.raphaelInitialize = function(callback) {
-        if(typeof netdataStopRaphael === 'undefined' || !netdataStopRaphael) {
-            $.ajax({
-                url: NETDATA.raphael_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function() {
-                NETDATA.registerChartLibrary('raphael', NETDATA.raphael_js);
-            })
-            .fail(function() {
-                NETDATA.chartLibraries.raphael.enabled = false;
-                NETDATA.error(100, NETDATA.raphael_js);
-            })
-            .always(function() {
-                if(typeof callback === "function")
-                    return callback();
-            });
-        }
-        else {
-            NETDATA.chartLibraries.raphael.enabled = false;
-            if(typeof callback === "function")
-                return callback();
+    this.updateChart = function (callback) {
+        if (this.debug) {
+            this.log('updateChart()');
         }
-    };
 
-    NETDATA.raphaelChartUpdate = function(state, data) {
-        $(state.element_chart).raphael(data.result, {
-            width: state.chartWidth(),
-            height: state.chartHeight()
-        });
+        if (this.fetching_data) {
+            if (this.debug) {
+                this.log('updateChart(): I am already updating...');
+            }
 
-        return false;
-    };
+            if (typeof callback === 'function') {
+                return callback(false, 'already running');
+            }
 
-    NETDATA.raphaelChartCreate = function(state, data) {
-        $(state.element_chart).raphael(data.result, {
-            width: state.chartWidth(),
-            height: state.chartHeight()
-        });
+            return;
+        }
 
-        return false;
-    };
+        // due to late initialization of charts and libraries
+        // we need to check this too
+        // if (this.enabled === false) {
+        if (!this.enabled) {
+            if (this.debug) {
+                this.log('updateChart(): I am not enabled');
+            }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // C3
+            if (typeof callback === 'function') {
+                return callback(false, 'not enabled');
+            }
 
-    NETDATA.c3Initialize = function(callback) {
-        if(typeof netdataNoC3 === 'undefined' || !netdataNoC3) {
+            return;
+        }
 
-            // C3 requires D3
-            if(!NETDATA.chartLibraries.d3.initialized) {
-                if(NETDATA.chartLibraries.d3.enabled) {
-                    NETDATA.d3Initialize(function() {
-                        NETDATA.c3Initialize(callback);
-                    });
-                }
-                else {
-                    NETDATA.chartLibraries.c3.enabled = false;
-                    if(typeof callback === "function")
-                        return callback();
-                }
+        // if (canBeRendered() === false) {
+        if (!canBeRendered()) {
+            if (this.debug) {
+                this.log('updateChart(): cannot be rendered');
             }
-            else {
-                NETDATA._loadCSS(NETDATA.c3_css);
 
-                $.ajax({
-                    url: NETDATA.c3_js,
-                    cache: true,
-                    dataType: "script",
-                    xhrFields: { withCredentials: true } // required for the cookie
-                })
-                .done(function() {
-                    NETDATA.registerChartLibrary('c3', NETDATA.c3_js);
-                })
-                .fail(function() {
-                    NETDATA.chartLibraries.c3.enabled = false;
-                    NETDATA.error(100, NETDATA.c3_js);
-                })
-                .always(function() {
-                    if(typeof callback === "function")
-                        return callback();
-                });
+            if (typeof callback === 'function') {
+                return callback(false, 'cannot be rendered');
             }
-        }
-        else {
-            NETDATA.chartLibraries.c3.enabled = false;
-            if(typeof callback === "function")
-                return callback();
-        }
-    };
 
-    NETDATA.c3ChartUpdate = function(state, data) {
-        state.c3_instance.destroy();
-        return NETDATA.c3ChartCreate(state, data);
+            return;
+        }
 
-        //state.c3_instance.load({
-        //  rows: data.result,
-        //  unload: true
-        //});
+        if (that.dom_created !== true) {
+            if (this.debug) {
+                this.log('updateChart(): creating DOM');
+            }
 
-        //return true;
-    };
+            createDOM();
+        }
 
-    NETDATA.c3ChartCreate = function(state, data) {
+        if (this.chart === null) {
+            if (this.debug) {
+                this.log('updateChart(): getting chart');
+            }
 
-        state.element_chart.id = 'c3-' + state.uuid;
-        // console.log('id = ' + state.element_chart.id);
+            return this.getChart(function () {
+                return that.updateChart(callback);
+            });
+        }
 
-        state.c3_instance = c3.generate({
-            bindto: '#' + state.element_chart.id,
-            size: {
-                width: state.chartWidth(),
-                height: state.chartHeight()
-            },
-            color: {
-                pattern: state.chartColors()
-            },
-            data: {
-                x: 'time',
-                rows: data.result,
-                type: (state.chart.chart_type === 'line')?'spline':'area-spline'
-            },
-            axis: {
-                x: {
-                    type: 'timeseries',
-                    tick: {
-                        format: function(x) {
-                            return NETDATA.dateTime.xAxisTimeString(x);
-                        }
-                    }
+        if (this.library.initialized === false) {
+            if (this.library.enabled) {
+                if (this.debug) {
+                    this.log('updateChart(): initializing chart library');
                 }
-            },
-            grid: {
-                x: {
-                    show: true
-                },
-                y: {
-                    show: true
+
+                return this.library.initialize(function () {
+                    return that.updateChart(callback);
+                });
+            } else {
+                error('chart library "' + this.library_name + '" is not available.');
+
+                if (typeof callback === 'function') {
+                    return callback(false, 'library not available');
                 }
-            },
-            point: {
-                show: false
-            },
-            line: {
-                connectNull: false
-            },
-            transition: {
-                duration: 0
-            },
-            interaction: {
-                enabled: true
+
+                return;
             }
-        });
+        }
 
-        // console.log(state.c3_instance);
+        this.clearSelection();
+        this.chartURL();
 
-        return true;
-    };
+        NETDATA.statistics.refreshes_total++;
+        NETDATA.statistics.refreshes_active++;
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // d3pie
+        if (NETDATA.statistics.refreshes_active > NETDATA.statistics.refreshes_active_max) {
+            NETDATA.statistics.refreshes_active_max = NETDATA.statistics.refreshes_active;
+        }
 
-    NETDATA.d3pieInitialize = function(callback) {
-        if(typeof netdataNoD3pie === 'undefined' || !netdataNoD3pie) {
+        let ok = false;
+        this.fetching_data = true;
 
-            // d3pie requires D3
-            if(!NETDATA.chartLibraries.d3.initialized) {
-                if(NETDATA.chartLibraries.d3.enabled) {
-                    NETDATA.d3Initialize(function() {
-                        NETDATA.d3pieInitialize(callback);
-                    });
-                }
-                else {
-                    NETDATA.chartLibraries.d3pie.enabled = false;
-                    if(typeof callback === "function")
-                        return callback();
-                }
+        if (netdataSnapshotData !== null) {
+            let key = this.chartDataUniqueID();
+            let data = this.getSnapshotData(key);
+            if (data !== null) {
+                ok = true;
+                data = NETDATA.xss.checkData('/api/v1/data', data, this.library.xssRegexIgnore);
+                this.updateChartWithData(data);
+            } else {
+                ok = false;
+                error('cannot get data from snapshot for key: "' + key + '"');
+                that.tm.last_autorefreshed = Date.now();
             }
-            else {
-                $.ajax({
-                    url: NETDATA.d3pie_js,
-                    cache: true,
-                    dataType: "script",
-                    xhrFields: { withCredentials: true } // required for the cookie
-                })
-                    .done(function() {
-                        NETDATA.registerChartLibrary('d3pie', NETDATA.d3pie_js);
-                    })
-                    .fail(function() {
-                        NETDATA.chartLibraries.d3pie.enabled = false;
-                        NETDATA.error(100, NETDATA.d3pie_js);
-                    })
-                    .always(function() {
-                        if(typeof callback === "function")
-                            return callback();
-                    });
+
+            NETDATA.statistics.refreshes_active--;
+            this.fetching_data = false;
+
+            if (typeof callback === 'function') {
+                callback(ok, 'snapshot');
             }
+
+            return;
         }
-        else {
-            NETDATA.chartLibraries.d3pie.enabled = false;
-            if(typeof callback === "function")
-                return callback();
+
+        if (this.debug) {
+            this.log('updating from ' + this.data_url);
         }
-    };
 
-    NETDATA.d3pieSetContent = function(state, data, index) {
-        state.legendFormatValueDecimalsFromMinMax(
-            data.min,
-            data.max
-        );
+        this.xhr = $.ajax({
+            url: this.data_url,
+            cache: false,
+            async: true,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkData('/api/v1/data', data, that.library.xssRegexIgnore);
 
-        var content = [];
-        var colors = state.chartColors();
-        var len = data.result.labels.length;
-        for(var i = 1; i < len ; i++) {
-            var label = data.result.labels[i];
-            var value = data.result.data[index][label];
-            var color = colors[i - 1];
-
-            if(value !== null && value > 0) {
-                content.push({
-                    label: label,
-                    value: value,
-                    color: color
-                });
-            }
-        }
+                that.xhr = undefined;
+                that.retries_on_data_failures = 0;
+                ok = true;
 
-        if(content.length === 0)
-            content.push({
-                label: 'no data',
-                value: 100,
-                color: '#666666'
-            });
+                if (that.debug) {
+                    that.log('data received. updating chart.');
+                }
+
+                that.updateChartWithData(data);
+            })
+            .fail(function (msg) {
+                that.xhr = undefined;
+
+                if (msg.statusText !== 'abort') {
+                    that.retries_on_data_failures++;
+                    if (that.retries_on_data_failures > NETDATA.options.current.retries_on_data_failures) {
+                        // that.log('failed ' + that.retries_on_data_failures.toString() + ' times - giving up');
+                        that.retries_on_data_failures = 0;
+                        error('data download failed for url: ' + that.data_url);
+                    }
+                    else {
+                        that.tm.last_autorefreshed = Date.now();
+                        // that.log('failed ' + that.retries_on_data_failures.toString() + ' times, but I will retry');
+                    }
+                }
+            })
+            .always(function () {
+                that.xhr = undefined;
+
+                NETDATA.statistics.refreshes_active--;
+                that.fetching_data = false;
 
-        state.tmp.d3pie_last_slot = index;
-        return content;
+                if (typeof callback === 'function') {
+                    return callback(ok, 'download');
+                }
+            });
     };
 
-    NETDATA.d3pieDateRange = function(state, data, index) {
-        var dt = Math.round((data.before - data.after + 1) / data.points);
-        var dt_str = NETDATA.seconds4human(dt);
+    const __isVisible = function () {
+        let ret = true;
 
-        var before = data.result.data[index].time;
-        var after = before - (dt * 1000);
+        if (NETDATA.options.current.update_only_visible !== false) {
+            // tolerance is the number of pixels a chart can be off-screen
+            // to consider it as visible and refresh it as if was visible
+            let tolerance = 0;
 
-        var d1 = NETDATA.dateTime.localeDateString(after);
-        var t1 = NETDATA.dateTime.localeTimeString(after);
-        var d2 = NETDATA.dateTime.localeDateString(before);
-        var t2 = NETDATA.dateTime.localeTimeString(before);
+            that.tm.last_visible_check = Date.now();
 
-        if(d1 === d2)
-            return d1 + ' ' + t1 + ' to ' + t2 + ', ' + dt_str;
+            let rect = that.element.getBoundingClientRect();
 
-        return d1 + ' ' + t1 + ' to ' + d2 + ' ' + t2 + ', ' + dt_str;
-    };
+            let screenTop = window.scrollY;
+            let screenBottom = screenTop + window.innerHeight;
 
-    NETDATA.d3pieSetSelection = function(state, t) {
-        if(state.timeIsVisible(t) !== true)
-            return NETDATA.d3pieClearSelection(state, true);
+            let chartTop = rect.top + screenTop;
+            let chartBottom = chartTop + rect.height;
 
-        var slot = state.calculateRowForTime(t);
-        slot = state.data.result.data.length - slot - 1;
+            ret = !(rect.width === 0 || rect.height === 0 || chartBottom + tolerance < screenTop || chartTop - tolerance > screenBottom);
+        }
 
-        if(slot < 0 || slot >= state.data.result.length)
-            return NETDATA.d3pieClearSelection(state, true);
+        if (that.debug) {
+            that.log('__isVisible(): ' + ret);
+        }
 
-        if(state.tmp.d3pie_last_slot === slot) {
-            // we already show this slot, don't do anything
-            return true;
+        return ret;
+    };
+
+    this.isVisible = function (nocache) {
+        // this.log('last_visible_check: ' + this.tm.last_visible_check + ', last_page_scroll: ' + NETDATA.options.last_page_scroll);
+
+        // caching - we do not evaluate the charts visibility
+        // if the page has not been scrolled since the last check
+        if ((typeof nocache !== 'undefined' && nocache)
+            || typeof this.tmp.___isVisible___ === 'undefined'
+            || this.tm.last_visible_check <= NETDATA.options.last_page_scroll) {
+            this.tmp.___isVisible___ = __isVisible();
+            if (this.tmp.___isVisible___) {
+                this.unhideChart();
+            } else {
+                this.hideChart();
+            }
         }
 
-        if(state.tmp.d3pie_timer === undefined) {
-            state.tmp.d3pie_timer = NETDATA.timeout.set(function() {
-                state.tmp.d3pie_timer = undefined;
-                NETDATA.d3pieChange(state, NETDATA.d3pieSetContent(state, state.data, slot), NETDATA.d3pieDateRange(state, state.data, slot));
-            }, 0);
+        if (this.debug) {
+            this.log('isVisible(' + nocache + '): ' + this.tmp.___isVisible___);
         }
 
-        return true;
+        return this.tmp.___isVisible___;
     };
 
-    NETDATA.d3pieClearSelection = function(state, force) {
-        if(typeof state.tmp.d3pie_timer !== 'undefined') {
-            NETDATA.timeout.clear(state.tmp.d3pie_timer);
-            state.tmp.d3pie_timer = undefined;
+    this.isAutoRefreshable = function () {
+        return (this.current.autorefresh);
+    };
+
+    this.canBeAutoRefreshed = function () {
+        if (this.enabled === false) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> not enabled');
+            }
+
+            return false;
         }
 
-        if(state.isAutoRefreshable() === true && state.data !== null && force !== true) {
-            NETDATA.d3pieChartUpdate(state, state.data);
+        if (this.running) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> already running');
+            }
+
+            return false;
         }
-        else {
-            if(state.tmp.d3pie_last_slot !== -1) {
-                state.tmp.d3pie_last_slot = -1;
-                NETDATA.d3pieChange(state, [{label: 'no data', value: 1, color: '#666666'}], 'no data available');
+
+        if (this.library === null || this.library.enabled === false) {
+            error('charting library "' + this.library_name + '" is not available');
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> chart library ' + this.library_name + ' is not available');
             }
+
+            return false;
         }
 
-        return true;
-    };
+        // if (this.isVisible() === false) {
+        if (!this.isVisible()) {
+            if (NETDATA.options.debug.visibility || this.debug) {
+                this.log('canBeAutoRefreshed() -> not visible');
+            }
 
-    NETDATA.d3pieChange = function(state, content, footer) {
-        if(state.d3pie_forced_subtitle === null) {
-            //state.d3pie_instance.updateProp("header.subtitle.text", state.units_current);
-            state.d3pie_instance.options.header.subtitle.text = state.units_current;
+            return false;
         }
 
-        if(state.d3pie_forced_footer === null) {
-            //state.d3pie_instance.updateProp("footer.text", footer);
-            state.d3pie_instance.options.footer.text = footer;
+        let now = Date.now();
+
+        if (this.current.force_update_at !== 0 && this.current.force_update_at < now) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> timed force update - allowing this update');
+            }
+
+            this.current.force_update_at = 0;
+            return true;
         }
 
-        //state.d3pie_instance.updateProp("data.content", content);
-        state.d3pie_instance.options.data.content = content;
-        state.d3pie_instance.destroy();
-        state.d3pie_instance.recreate();
-        return true;
-    };
+        if (this.isAutoRefreshable() === false) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> not auto-refreshable');
+            }
 
-    NETDATA.d3pieChartUpdate = function(state, data) {
-        return NETDATA.d3pieChange(state, NETDATA.d3pieSetContent(state, data, 0), NETDATA.d3pieDateRange(state, data, 0));
-    };
+            return false;
+        }
 
-    NETDATA.d3pieChartCreate = function(state, data) {
+        // allow the first update, even if the page is not visible
+        if (NETDATA.options.page_is_visible === false && this.updates_counter && this.updates_since_last_unhide) {
+            if (NETDATA.options.debug.focus || this.debug) {
+                this.log('canBeAutoRefreshed() -> not the first update, and page does not have focus');
+            }
 
-        state.element_chart.id = 'd3pie-' + state.uuid;
-        // console.log('id = ' + state.element_chart.id);
+            return false;
+        }
 
-        var content = NETDATA.d3pieSetContent(state, data, 0);
+        if (this.needsRecreation()) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> needs re-creation.');
+            }
 
-        state.d3pie_forced_title = NETDATA.dataAttribute(state.element, 'd3pie-title', null);
-        state.d3pie_forced_subtitle = NETDATA.dataAttribute(state.element, 'd3pie-subtitle', null);
-        state.d3pie_forced_footer = NETDATA.dataAttribute(state.element, 'd3pie-footer', null);
+            return true;
+        }
 
-        state.d3pie_options = {
-            header: {
-                title: {
-                    text: (state.d3pie_forced_title !== null) ? state.d3pie_forced_title : state.title,
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-title-color', NETDATA.themes.current.d3pie.title),
-                    fontSize: NETDATA.dataAttribute(state.element, 'd3pie-title-fontsize', 12),
-                    fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-title-fontweight', "bold"),
-                    font: NETDATA.dataAttribute(state.element, 'd3pie-title-font', "arial")
-                },
-                subtitle: {
-                    text: (state.d3pie_forced_subtitle !== null) ? state.d3pie_forced_subtitle : state.units_current,
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-color', NETDATA.themes.current.d3pie.subtitle),
-                    fontSize: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-fontsize', 10),
-                    fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-fontweight', "normal"),
-                    font: NETDATA.dataAttribute(state.element, 'd3pie-subtitle-font', "arial")
-                },
-                titleSubtitlePadding: 1
-            },
-            footer: {
-                text: (state.d3pie_forced_footer !== null) ? state.d3pie_forced_footer : NETDATA.d3pieDateRange(state, data, 0),
-                color: NETDATA.dataAttribute(state.element, 'd3pie-footer-color', NETDATA.themes.current.d3pie.footer),
-                fontSize: NETDATA.dataAttribute(state.element, 'd3pie-footer-fontsize', 9),
-                fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-footer-fontweight', "bold"),
-                font: NETDATA.dataAttribute(state.element, 'd3pie-footer-font', "arial"),
-                location: NETDATA.dataAttribute(state.element, 'd3pie-footer-location', "bottom-center") // bottom-left, bottom-center, bottom-right
-            },
-            size: {
-                canvasHeight: state.chartHeight(),
-                canvasWidth: state.chartWidth(),
-                pieInnerRadius: NETDATA.dataAttribute(state.element, 'd3pie-pieinnerradius', "45%"),
-                pieOuterRadius: NETDATA.dataAttribute(state.element, 'd3pie-pieouterradius', "80%")
-            },
-            data: {
-                // none, random, value-asc, value-desc, label-asc, label-desc
-                sortOrder: NETDATA.dataAttribute(state.element, 'd3pie-sortorder', "value-desc"),
-                smallSegmentGrouping: {
-                    enabled: NETDATA.dataAttributeBoolean(state.element, "d3pie-smallsegmentgrouping-enabled", false),
-                    value: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-value', 1),
-                    // percentage, value
-                    valueType: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-valuetype', "percentage"),
-                    label: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-label', "other"),
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-smallsegmentgrouping-color', NETDATA.themes.current.d3pie.other)
-                },
+        if (NETDATA.options.auto_refresher_stop_until >= now) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed() -> stopped until is in future.');
+            }
 
-                // REQUIRED! This is where you enter your pie data; it needs to be an array of objects
-                // of this form: { label: "label", value: 1.5, color: "#000000" } - color is optional
-                content: content
-            },
-            labels: {
-                outer: {
-                    // label, value, percentage, label-value1, label-value2, label-percentage1, label-percentage2
-                    format: NETDATA.dataAttribute(state.element, 'd3pie-labels-outer-format', "label-value1"),
-                    hideWhenLessThanPercentage: NETDATA.dataAttribute(state.element, 'd3pie-labels-outer-hidewhenlessthanpercentage', null),
-                    pieDistance: NETDATA.dataAttribute(state.element, 'd3pie-labels-outer-piedistance', 15)
-                },
-                inner: {
-                    // label, value, percentage, label-value1, label-value2, label-percentage1, label-percentage2
-                    format: NETDATA.dataAttribute(state.element, 'd3pie-labels-inner-format', "percentage"),
-                    hideWhenLessThanPercentage: NETDATA.dataAttribute(state.element, 'd3pie-labels-inner-hidewhenlessthanpercentage', 2)
-                },
-                mainLabel: {
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-color', NETDATA.themes.current.d3pie.mainlabel), // or 'segment' for dynamic color
-                    font: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-font', "arial"),
-                    fontSize: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-fontsize', 10),
-                    fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-labels-mainLabel-fontweight', "normal")
-                },
-                percentage: {
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-color', NETDATA.themes.current.d3pie.percentage),
-                    font: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-font', "arial"),
-                    fontSize: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-fontsize', 10),
-                    fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-labels-percentage-fontweight', "bold"),
-                    decimalPlaces: 0
-                },
-                value: {
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-color', NETDATA.themes.current.d3pie.value),
-                    font: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-font', "arial"),
-                    fontSize: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-fontsize', 10),
-                    fontWeight: NETDATA.dataAttribute(state.element, 'd3pie-labels-value-fontweight', "bold")
-                },
-                lines: {
-                    enabled: NETDATA.dataAttributeBoolean(state.element, 'd3pie-labels-lines-enabled', true),
-                    style: NETDATA.dataAttribute(state.element, 'd3pie-labels-lines-style', "curved"),
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-labels-lines-color', "segment") // "segment" or a hex color
-                },
-                truncation: {
-                    enabled: NETDATA.dataAttributeBoolean(state.element, 'd3pie-labels-truncation-enabled', false),
-                    truncateLength: NETDATA.dataAttribute(state.element, 'd3pie-labels-truncation-truncatelength', 30)
-                },
-                formatter: function(context) {
-                    // console.log(context);
-                    if(context.part === 'value')
-                        return state.legendFormatValue(context.value);
-                    if(context.part === 'percentage')
-                        return context.label + '%';
+            return false;
+        }
 
-                    return context.label;
-                }
-            },
-            effects: {
-                load: {
-                    effect: "none", // none / default
-                    speed: 0 // commented in the d3pie code to speed it up
-                },
-                pullOutSegmentOnClick: {
-                    effect: "bounce", // none / linear / bounce / elastic / back
-                    speed: 400,
-                    size: 5
-                },
-                highlightSegmentOnMouseover: true,
-                highlightLuminosity: -0.2
-            },
-            tooltips: {
-                enabled: false,
-                type: "placeholder", // caption|placeholder
-                string: "",
-                placeholderParser: null, // function
-                styles: {
-                    fadeInSpeed: 250,
-                    backgroundColor: NETDATA.themes.current.d3pie.tooltip_bg,
-                    backgroundOpacity: 0.5,
-                    color: NETDATA.themes.current.d3pie.tooltip_fg,
-                    borderRadius: 2,
-                    font: "arial",
-                    fontSize: 12,
-                    padding: 4
+        // options valid only for autoRefresh()
+        if (NETDATA.globalPanAndZoom.isActive()) {
+            if (NETDATA.globalPanAndZoom.shouldBeAutoRefreshed(this)) {
+                if (this.debug) {
+                    this.log('canBeAutoRefreshed(): global panning: I need an update.');
                 }
-            },
-            misc: {
-                colors: {
-                    background: 'transparent', // transparent or color #
-                    // segments: state.chartColors(),
-                    segmentStroke: NETDATA.dataAttribute(state.element, 'd3pie-misc-colors-segmentstroke', NETDATA.themes.current.d3pie.segment_stroke)
-                },
-                gradient: {
-                    enabled: NETDATA.dataAttributeBoolean(state.element, 'd3pie-misc-gradient-enabled', false),
-                    percentage: NETDATA.dataAttribute(state.element, 'd3pie-misc-colors-percentage', 95),
-                    color: NETDATA.dataAttribute(state.element, 'd3pie-misc-gradient-color', NETDATA.themes.current.d3pie.gradient_color)
-                },
-                canvasPadding: {
-                    top: 5,
-                    right: 5,
-                    bottom: 5,
-                    left: 5
-                },
-                pieCenterOffset: {
-                    x: 0,
-                    y: 0
-                },
-                cssPrefix: NETDATA.dataAttribute(state.element, 'd3pie-cssprefix', null)
-            },
-            callbacks: {
-                onload: null,
-                onMouseoverSegment: null,
-                onMouseoutSegment: null,
-                onClickSegment: null
+
+                return true;
             }
-        };
+            else {
+                if (this.debug) {
+                    this.log('canBeAutoRefreshed(): global panning: I am already up to date.');
+                }
 
-        state.d3pie_instance = new d3pie(state.element_chart, state.d3pie_options);
-        return true;
-    };
+                return false;
+            }
+        }
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // D3
+        if (this.selected) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed(): I have a selection in place.');
+            }
 
-    NETDATA.d3Initialize = function(callback) {
-        if(typeof netdataStopD3 === 'undefined' || !netdataStopD3) {
-            $.ajax({
-                url: NETDATA.d3_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function() {
-                NETDATA.registerChartLibrary('d3', NETDATA.d3_js);
-            })
-            .fail(function() {
-                NETDATA.chartLibraries.d3.enabled = false;
-                NETDATA.error(100, NETDATA.d3_js);
-            })
-            .always(function() {
-                if(typeof callback === "function")
-                    return callback();
-            });
+            return false;
         }
-        else {
-            NETDATA.chartLibraries.d3.enabled = false;
-            if(typeof callback === "function")
-                return callback();
+
+        if (this.paused) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed(): I am paused.');
+            }
+
+            return false;
         }
-    };
 
-    NETDATA.d3ChartUpdate = function(state, data) {
-        void(state);
-        void(data);
+        let data_update_every = this.data_update_every;
+        if (typeof this.force_update_every === 'number') {
+            data_update_every = this.force_update_every;
+        }
 
-        return false;
-    };
+        if (now - this.tm.last_autorefreshed >= data_update_every) {
+            if (this.debug) {
+                this.log('canBeAutoRefreshed(): It is time to update me. Now: ' + now.toString() + ', last_autorefreshed: ' + this.tm.last_autorefreshed + ', data_update_every: ' + data_update_every + ', delta: ' + (now - this.tm.last_autorefreshed).toString());
+            }
 
-    NETDATA.d3ChartCreate = function(state, data) {
-        void(state);
-        void(data);
+            return true;
+        }
 
         return false;
     };
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // google charts
+    this.autoRefresh = function (callback) {
+        let state = that;
 
-    NETDATA.googleInitialize = function(callback) {
-        if(typeof netdataNoGoogleCharts === 'undefined' || !netdataNoGoogleCharts) {
-            $.ajax({
-                url: NETDATA.google_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-            .done(function() {
-                NETDATA.registerChartLibrary('google', NETDATA.google_js);
-                google.load('visualization', '1.1', {
-                    'packages': ['corechart', 'controls'],
-                    'callback': callback
-                });
-            })
-            .fail(function() {
-                NETDATA.chartLibraries.google.enabled = false;
-                NETDATA.error(100, NETDATA.google_js);
-                if(typeof callback === "function")
+        if (state.canBeAutoRefreshed() && state.running === false) {
+            state.running = true;
+            state.updateChart(function () {
+                state.running = false;
+
+                if (typeof callback === 'function') {
                     return callback();
+                }
             });
-        }
-        else {
-            NETDATA.chartLibraries.google.enabled = false;
-            if(typeof callback === "function")
+        } else {
+            if (typeof callback === 'function') {
                 return callback();
+            }
         }
     };
 
-    NETDATA.googleChartUpdate = function(state, data) {
-        var datatable = new google.visualization.DataTable(data.result);
-        state.google_instance.draw(datatable, state.google_options);
-        return true;
+    this.__defaultsFromDownloadedChart = function (chart) {
+        this.chart = chart;
+        this.chart_url = chart.url;
+        this.data_update_every = chart.update_every * 1000;
+        this.data_points = Math.round(this.chartWidth() / this.chartPixelsPerPoint());
+        this.tm.last_info_downloaded = Date.now();
+
+        if (this.title === null) {
+            this.title = chart.title;
+        }
+
+        if (this.units === null) {
+            this.units = chart.units;
+            this.units_current = this.units;
+        }
     };
 
-    NETDATA.googleChartCreate = function(state, data) {
-        var datatable = new google.visualization.DataTable(data.result);
+    // fetch the chart description from the netdata server
+    this.getChart = function (callback) {
+        this.chart = NETDATA.chartRegistry.get(this.host, this.id);
+        if (this.chart) {
+            this.__defaultsFromDownloadedChart(this.chart);
 
-        state.google_options = {
-            colors: state.chartColors(),
+            if (typeof callback === 'function') {
+                return callback();
+            }
+        } else if (netdataSnapshotData !== null) {
+            // console.log(this);
+            // console.log(NETDATA.chartRegistry);
+            NETDATA.error(404, 'host: ' + this.host + ', chart: ' + this.id);
+            error('chart not found in snapshot');
 
-            // do not set width, height - the chart resizes itself
-            //width: state.chartWidth(),
-            //height: state.chartHeight(),
-            lineWidth: 1,
-            title: state.title,
-            fontSize: 11,
-            hAxis: {
-            //  title: "Time of Day",
-            //  format:'HH:mm:ss',
-                viewWindowMode: 'maximized',
-                slantedText: false,
-                format:'HH:mm:ss',
-                textStyle: {
-                    fontSize: 9
-                },
-                gridlines: {
-                    color: '#EEE'
-                }
-            },
-            vAxis: {
-                title: state.units_current,
-                viewWindowMode: 'pretty',
-                minValue: -0.1,
-                maxValue: 0.1,
-                direction: 1,
-                textStyle: {
-                    fontSize: 9
-                },
-                gridlines: {
-                    color: '#EEE'
-                }
-            },
-            chartArea: {
-                width: '65%',
-                height: '80%'
-            },
-            focusTarget: 'category',
-            annotation: {
-                '1': {
-                    style: 'line'
-                }
-            },
-            pointsVisible: 0,
-            titlePosition: 'out',
-            titleTextStyle: {
-                fontSize: 11
-            },
-            tooltip: {
-                isHtml: false,
-                ignoreBounds: true,
-                textStyle: {
-                    fontSize: 9
-                }
-            },
-            curveType: 'function',
-            areaOpacity: 0.3,
-            isStacked: false
-        };
+            if (typeof callback === 'function') {
+                return callback();
+            }
+        } else {
+            this.chart_url = "/api/v1/chart?chart=" + this.id;
 
-        switch(state.chart.chart_type) {
-            case "area":
-                state.google_options.vAxis.viewWindowMode = 'maximized';
-                state.google_options.areaOpacity = NETDATA.options.current.color_fill_opacity_area;
-                state.google_instance = new google.visualization.AreaChart(state.element_chart);
-                break;
+            if (this.debug) {
+                this.log('downloading ' + this.chart_url);
+            }
 
-            case "stacked":
-                state.google_options.isStacked = true;
-                state.google_options.areaOpacity = NETDATA.options.current.color_fill_opacity_stacked;
-                state.google_options.vAxis.viewWindowMode = 'maximized';
-                state.google_options.vAxis.minValue = null;
-                state.google_options.vAxis.maxValue = null;
-                state.google_instance = new google.visualization.AreaChart(state.element_chart);
-                break;
+            $.ajax({
+                url: this.host + this.chart_url,
+                cache: false,
+                async: true,
+                xhrFields: {withCredentials: true} // required for the cookie
+            })
+                .done(function (chart) {
+                    chart = NETDATA.xss.checkOptional('/api/v1/chart', chart);
 
-            default:
-            case "line":
-                state.google_options.lineWidth = 2;
-                state.google_instance = new google.visualization.LineChart(state.element_chart);
-                break;
+                    chart.url = that.chart_url;
+                    that.__defaultsFromDownloadedChart(chart);
+                    NETDATA.chartRegistry.add(that.host, that.id, chart);
+                })
+                .fail(function () {
+                    NETDATA.error(404, that.chart_url);
+                    error('chart not found on url "' + that.chart_url + '"');
+                })
+                .always(function () {
+                    if (typeof callback === 'function') {
+                        return callback();
+                    }
+                });
         }
-
-        state.google_instance.draw(datatable, state.google_options);
-        return true;
     };
 
-    // ----------------------------------------------------------------------------------------------------------------
-
-    NETDATA.easypiechartPercentFromValueMinMax = function(state, value, min, max) {
-        if(typeof value !== 'number') value = 0;
-        if(typeof min !== 'number') min = 0;
-        if(typeof max !== 'number') max = 0;
+    // ============================================================================================================
+    // INITIALIZATION
 
-        if(min > max) {
-            var t = min;
-            min = max;
-            max = t;
-        }
+    initDOM();
+    init('fast');
+};
 
-        if(min > value) min = value;
-        if(max < value) max = value;
+NETDATA.resetAllCharts = function (state) {
+    // first clear the global selection sync
+    // to make sure no chart is in selected state
+    NETDATA.globalSelectionSync.stop();
 
-        state.legendFormatValueDecimalsFromMinMax(min, max);
+    // there are 2 possibilities here
+    // a. state is the global Pan and Zoom master
+    // b. state is not the global Pan and Zoom master
+    let master = true;
+    if (NETDATA.globalPanAndZoom.isMaster(state) === false) {
+        master = false;
+    }
 
-        if(state.tmp.easyPieChartMin === null && min > 0) min = 0;
-        if(state.tmp.easyPieChartMax === null && max < 0) max = 0;
+    // clear the global Pan and Zoom
+    // this will also refresh the master
+    // and unblock any charts currently mirroring the master
+    NETDATA.globalPanAndZoom.clearMaster();
 
-        var pcent;
+    // if we were not the master, reset our status too
+    // this is required because most probably the mouse
+    // is over this chart, blocking it from auto-refreshing
+    if (master === false && (state.paused || state.selected)) {
+        state.resetChart();
+    }
+};
 
-        if(min < 0 && max > 0) {
-            // it is both positive and negative
-            // zero at the top center of the chart
-            max = (-min > max)? -min : max;
-            pcent = Math.round(value * 100 / max);
-        }
-        else if(value >= 0 && min >= 0 && max >= 0) {
-            // clockwise
-            pcent = Math.round((value - min) * 100 / (max - min));
-            if(pcent === 0) pcent = 0.1;
-        }
-        else {
-            // counter clockwise
-            pcent = Math.round((value - max) * 100 / (max - min));
-            if(pcent === 0) pcent = -0.1;
-        }
+// get or create a chart state, given a DOM element
+NETDATA.chartState = function (element) {
+    let self = $(element);
 
-        return pcent;
-    };
+    let state = self.data('netdata-state-object') || null;
+    if (state === null) {
+        state = new chartState(element);
+        self.data('netdata-state-object', state);
+    }
+    return state;
+};
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // easy-pie-chart
+// ----------------------------------------------------------------------------------------------------------------
+// Library functions
 
-    NETDATA.easypiechartInitialize = function(callback) {
-        if(typeof netdataNoEasyPieChart === 'undefined' || !netdataNoEasyPieChart) {
-            $.ajax({
-                url: NETDATA.easypiechart_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-                .done(function() {
-                    NETDATA.registerChartLibrary('easypiechart', NETDATA.easypiechart_js);
-                })
-                .fail(function() {
-                    NETDATA.chartLibraries.easypiechart.enabled = false;
-                    NETDATA.error(100, NETDATA.easypiechart_js);
-                })
-                .always(function() {
-                    if(typeof callback === "function")
-                        return callback();
-                })
+// Load a script without jquery
+// This is used to load jquery - after it is loaded, we use jquery
+NETDATA._loadjQuery = function (callback) {
+    if (typeof jQuery === 'undefined') {
+        if (NETDATA.options.debug.main_loop) {
+            console.log('loading ' + NETDATA.jQuery);
         }
-        else {
-            NETDATA.chartLibraries.easypiechart.enabled = false;
-            if(typeof callback === "function")
+
+        let script = document.createElement('script');
+        script.type = 'text/javascript';
+        script.async = true;
+        script.src = NETDATA.jQuery;
+
+        // script.onabort = onError;
+        script.onerror = function () {
+            NETDATA.error(101, NETDATA.jQuery);
+        };
+        if (typeof callback === "function") {
+            script.onload = function () {
+                $ = jQuery;
                 return callback();
+            };
         }
-    };
 
-    NETDATA.easypiechartClearSelection = function(state, force) {
-        if(typeof state.tmp.easyPieChartEvent !== 'undefined' && typeof state.tmp.easyPieChartEvent.timer !== 'undefined') {
-            NETDATA.timeout.clear(state.tmp.easyPieChartEvent.timer);
-            state.tmp.easyPieChartEvent.timer = undefined;
-        }
+        let s = document.getElementsByTagName('script')[0];
+        s.parentNode.insertBefore(script, s);
+    }
+    else if (typeof callback === "function") {
+        $ = jQuery;
+        return callback();
+    }
+};
 
-        if(state.isAutoRefreshable() === true && state.data !== null && force !== true) {
-            NETDATA.easypiechartChartUpdate(state, state.data);
-        }
-        else {
-            state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(null);
-            state.tmp.easyPieChart_instance.update(0);
-        }
-        state.tmp.easyPieChart_instance.enableAnimation();
+NETDATA._loadCSS = function (filename) {
+    // don't use jQuery here
+    // styles are loaded before jQuery
+    // to eliminate showing an unstyled page to the user
 
-        return true;
-    };
+    let fileref = document.createElement("link");
+    fileref.setAttribute("rel", "stylesheet");
+    fileref.setAttribute("type", "text/css");
+    fileref.setAttribute("href", filename);
+
+    if (typeof fileref !== 'undefined') {
+        document.getElementsByTagName("head")[0].appendChild(fileref);
+    }
+};
 
-    NETDATA.easypiechartSetSelection = function(state, t) {
-        if(state.timeIsVisible(t) !== true)
-            return NETDATA.easypiechartClearSelection(state, true);
+// user function to signal us the DOM has been
+// updated.
+NETDATA.updatedDom = function () {
+    NETDATA.options.updated_dom = true;
+};
 
-        var slot = state.calculateRowForTime(t);
-        if(slot < 0 || slot >= state.data.result.length)
-            return NETDATA.easypiechartClearSelection(state, true);
+NETDATA.ready = function (callback) {
+    NETDATA.options.pauseCallback = callback;
+};
 
-        if(typeof state.tmp.easyPieChartEvent === 'undefined') {
-            state.tmp.easyPieChartEvent = {
-                timer: undefined,
-                value: 0,
-                pcent: 0
-            };
+NETDATA.pause = function (callback) {
+    if (typeof callback === 'function') {
+        if (NETDATA.options.pause) {
+            return callback();
+        } else {
+            NETDATA.options.pauseCallback = callback;
         }
+    }
+};
 
-        var value = state.data.result[state.data.result.length - 1 - slot];
-        var min = (state.tmp.easyPieChartMin === null)?NETDATA.commonMin.get(state):state.tmp.easyPieChartMin;
-        var max = (state.tmp.easyPieChartMax === null)?NETDATA.commonMax.get(state):state.tmp.easyPieChartMax;
-        var pcent = NETDATA.easypiechartPercentFromValueMinMax(state, value, min, max);
+NETDATA.unpause = function () {
+    NETDATA.options.pauseCallback = null;
+    NETDATA.options.updated_dom = true;
+    NETDATA.options.pause = false;
+};
 
-        state.tmp.easyPieChartEvent.value = value;
-        state.tmp.easyPieChartEvent.pcent = pcent;
-        state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(value);
+// ----------------------------------------------------------------------------------------------------------------
 
-        if(state.tmp.easyPieChartEvent.timer === undefined) {
-            state.tmp.easyPieChart_instance.disableAnimation();
+// this is purely sequential charts refresher
+// it is meant to be autonomous
+NETDATA.chartRefresherNoParallel = function (index, callback) {
+    let targets = NETDATA.intersectionObserver.targets();
 
-            state.tmp.easyPieChartEvent.timer = NETDATA.timeout.set(function() {
-                state.tmp.easyPieChartEvent.timer = undefined;
-                state.tmp.easyPieChart_instance.update(state.tmp.easyPieChartEvent.pcent);
-            }, 0);
+    if (NETDATA.options.debug.main_loop) {
+        console.log('NETDATA.chartRefresherNoParallel(' + index + ')');
+    }
+
+    if (NETDATA.options.updated_dom) {
+        // the dom has been updated
+        // get the dom parts again
+        NETDATA.parseDom(callback);
+        return;
+    }
+    if (index >= targets.length) {
+        if (NETDATA.options.debug.main_loop) {
+            console.log('waiting to restart main loop...');
         }
 
-        return true;
-    };
+        NETDATA.options.auto_refresher_fast_weight = 0;
+        callback();
+    } else {
+        let state = targets[index];
 
-    NETDATA.easypiechartChartUpdate = function(state, data) {
-        var value, min, max, pcent;
+        if (NETDATA.options.auto_refresher_fast_weight < NETDATA.options.current.fast_render_timeframe) {
+            if (NETDATA.options.debug.main_loop) {
+                console.log('fast rendering...');
+            }
 
-        if(NETDATA.globalPanAndZoom.isActive() === true || state.isAutoRefreshable() === false) {
-            value = null;
-            pcent = 0;
-        }
-        else {
-            value = data.result[0];
-            min = (state.tmp.easyPieChartMin === null)?NETDATA.commonMin.get(state):state.tmp.easyPieChartMin;
-            max = (state.tmp.easyPieChartMax === null)?NETDATA.commonMax.get(state):state.tmp.easyPieChartMax;
-            pcent = NETDATA.easypiechartPercentFromValueMinMax(state, value, min, max);
+            if (state.isVisible()) {
+                NETDATA.timeout.set(function () {
+                    state.autoRefresh(function () {
+                        NETDATA.chartRefresherNoParallel(++index, callback);
+                    });
+                }, 0);
+            } else {
+                NETDATA.chartRefresherNoParallel(++index, callback);
+            }
+        } else {
+            if (NETDATA.options.debug.main_loop) {
+                console.log('waiting for next refresh...');
+            }
+            NETDATA.options.auto_refresher_fast_weight = 0;
+
+            NETDATA.timeout.set(function () {
+                state.autoRefresh(function () {
+                    NETDATA.chartRefresherNoParallel(++index, callback);
+                });
+            }, NETDATA.options.current.idle_between_charts);
         }
+    }
+};
 
-        state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(value);
-        state.tmp.easyPieChart_instance.update(pcent);
-        return true;
-    };
+NETDATA.chartRefresherWaitTime = function () {
+    return NETDATA.options.current.idle_parallel_loops;
+};
 
-    NETDATA.easypiechartChartCreate = function(state, data) {
-        var chart = $(state.element_chart);
-
-        var value = data.result[0];
-        var min = NETDATA.dataAttribute(state.element, 'easypiechart-min-value', null);
-        var max = NETDATA.dataAttribute(state.element, 'easypiechart-max-value', null);
-
-        if(min === null) {
-            min = NETDATA.commonMin.get(state);
-            state.tmp.easyPieChartMin = null;
-        }
-        else
-            state.tmp.easyPieChartMin = min;
-
-        if(max === null) {
-            max = NETDATA.commonMax.get(state);
-            state.tmp.easyPieChartMax = null;
-        }
-        else
-            state.tmp.easyPieChartMax = max;
-
-        var size = state.chartWidth();
-        var stroke = Math.floor(size / 22);
-        if(stroke < 3) stroke = 2;
-
-        var valuefontsize = Math.floor((size * 2 / 3) / 5);
-        var valuetop = Math.round((size - valuefontsize - (size / 40)) / 2);
-        state.tmp.easyPieChartLabel = document.createElement('span');
-        state.tmp.easyPieChartLabel.className = 'easyPieChartLabel';
-        state.tmp.easyPieChartLabel.innerText = state.legendFormatValue(value);
-        state.tmp.easyPieChartLabel.style.fontSize = valuefontsize + 'px';
-        state.tmp.easyPieChartLabel.style.top = valuetop.toString() + 'px';
-        state.element_chart.appendChild(state.tmp.easyPieChartLabel);
-
-        var titlefontsize = Math.round(valuefontsize * 1.6 / 3);
-        var titletop = Math.round(valuetop - (titlefontsize * 2) - (size / 40));
-        state.tmp.easyPieChartTitle = document.createElement('span');
-        state.tmp.easyPieChartTitle.className = 'easyPieChartTitle';
-        state.tmp.easyPieChartTitle.innerText = state.title;
-        state.tmp.easyPieChartTitle.style.fontSize = titlefontsize + 'px';
-        state.tmp.easyPieChartTitle.style.lineHeight = titlefontsize + 'px';
-        state.tmp.easyPieChartTitle.style.top = titletop.toString() + 'px';
-        state.element_chart.appendChild(state.tmp.easyPieChartTitle);
-
-        var unitfontsize = Math.round(titlefontsize * 0.9);
-        var unittop = Math.round(valuetop + (valuefontsize + unitfontsize) + (size / 40));
-        state.tmp.easyPieChartUnits = document.createElement('span');
-        state.tmp.easyPieChartUnits.className = 'easyPieChartUnits';
-        state.tmp.easyPieChartUnits.innerText = state.units_current;
-        state.tmp.easyPieChartUnits.style.fontSize = unitfontsize + 'px';
-        state.tmp.easyPieChartUnits.style.top = unittop.toString() + 'px';
-        state.element_chart.appendChild(state.tmp.easyPieChartUnits);
-
-        var barColor = NETDATA.dataAttribute(state.element, 'easypiechart-barcolor', undefined);
-        if(typeof barColor === 'undefined' || barColor === null)
-            barColor = state.chartCustomColors()[0];
-        else {
-            // <div ... data-easypiechart-barcolor="(function(percent){return(percent < 50 ? '#5cb85c' : percent < 85 ? '#f0ad4e' : '#cb3935');})" ...></div>
-            var tmp = eval(barColor);
-            if(typeof tmp === 'function')
-                barColor = tmp;
-        }
-
-        var pcent = NETDATA.easypiechartPercentFromValueMinMax(state, value, min, max);
-        chart.data('data-percent', pcent);
-
-        chart.easyPieChart({
-            barColor: barColor,
-            trackColor: NETDATA.dataAttribute(state.element, 'easypiechart-trackcolor', NETDATA.themes.current.easypiechart_track),
-            scaleColor: NETDATA.dataAttribute(state.element, 'easypiechart-scalecolor', NETDATA.themes.current.easypiechart_scale),
-            scaleLength: NETDATA.dataAttribute(state.element, 'easypiechart-scalelength', 5),
-            lineCap: NETDATA.dataAttribute(state.element, 'easypiechart-linecap', 'round'),
-            lineWidth: NETDATA.dataAttribute(state.element, 'easypiechart-linewidth', stroke),
-            trackWidth: NETDATA.dataAttribute(state.element, 'easypiechart-trackwidth', undefined),
-            size: NETDATA.dataAttribute(state.element, 'easypiechart-size', size),
-            rotate: NETDATA.dataAttribute(state.element, 'easypiechart-rotate', 0),
-            animate: NETDATA.dataAttribute(state.element, 'easypiechart-animate', {duration: 500, enabled: true}),
-            easing: NETDATA.dataAttribute(state.element, 'easypiechart-easing', undefined)
-        });
+// the default refresher
+NETDATA.chartRefresherLastRun = 0;
+NETDATA.chartRefresherRunsAfterParseDom = 0;
+NETDATA.chartRefresherTimeoutId = undefined;
 
-        // when we just re-create the chart
-        // do not animate the first update
-        var animate = true;
-        if(typeof state.tmp.easyPieChart_instance !== 'undefined')
-            animate = false;
+NETDATA.chartRefresherReschedule = function () {
+    if (NETDATA.options.current.async_on_scroll) {
+        if (NETDATA.chartRefresherTimeoutId) {
+            NETDATA.timeout.clear(NETDATA.chartRefresherTimeoutId);
+        }
+        NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(NETDATA.chartRefresher, NETDATA.options.current.onscroll_worker_duration_threshold);
+        //console.log('chartRefresherReschedule()');
+    }
+};
+
+NETDATA.chartRefresher = function () {
+    // console.log('chartRefresher() begin ' + (Date.now() - NETDATA.chartRefresherLastRun).toString() + ' ms since last run');
+
+    if (NETDATA.options.page_is_visible === false
+        && NETDATA.options.current.stop_updates_when_focus_is_lost
+        && NETDATA.chartRefresherLastRun > NETDATA.options.last_page_resize
+        && NETDATA.chartRefresherLastRun > NETDATA.options.last_page_scroll
+        && NETDATA.chartRefresherRunsAfterParseDom > 10
+    ) {
+        setTimeout(
+            NETDATA.chartRefresher,
+            NETDATA.options.current.idle_lost_focus
+        );
 
-        state.tmp.easyPieChart_instance = chart.data('easyPieChart');
-        if(animate === false) state.tmp.easyPieChart_instance.disableAnimation();
-        state.tmp.easyPieChart_instance.update(pcent);
-        if(animate === false) state.tmp.easyPieChart_instance.enableAnimation();
+        // console.log('chartRefresher() page without focus, will run in ' + NETDATA.options.current.idle_lost_focus.toString() + ' ms, ' + NETDATA.chartRefresherRunsAfterParseDom.toString());
+        return;
+    }
+    NETDATA.chartRefresherRunsAfterParseDom++;
 
-        state.legendSetUnitsString = function(units) {
-            if(typeof state.tmp.easyPieChartUnits !== 'undefined' && state.tmp.units !== units) {
-                state.tmp.easyPieChartUnits.innerText = units;
-                state.tmp.units = units;
-            }
-        };
-        state.legendShowUndefined = function() {
-            if(typeof state.tmp.easyPieChart_instance !== 'undefined')
-                NETDATA.easypiechartClearSelection(state);
-        };
+    let now = Date.now();
+    NETDATA.chartRefresherLastRun = now;
 
-        return true;
-    };
+    if (now < NETDATA.options.on_scroll_refresher_stop_until) {
+        NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
+            NETDATA.chartRefresher,
+            NETDATA.chartRefresherWaitTime()
+        );
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // gauge.js
+        // console.log('chartRefresher() end1 will run in ' + NETDATA.chartRefresherWaitTime().toString() + ' ms');
+        return;
+    }
 
-    NETDATA.gaugeInitialize = function(callback) {
-        if(typeof netdataNoGauge === 'undefined' || !netdataNoGauge) {
-            $.ajax({
-                url: NETDATA.gauge_js,
-                cache: true,
-                dataType: "script",
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-                .done(function() {
-                    NETDATA.registerChartLibrary('gauge', NETDATA.gauge_js);
-                })
-                .fail(function() {
-                    NETDATA.chartLibraries.gauge.enabled = false;
-                    NETDATA.error(100, NETDATA.gauge_js);
-                })
-                .always(function() {
-                    if(typeof callback === "function")
-                        return callback();
-                })
-        }
-        else {
-            NETDATA.chartLibraries.gauge.enabled = false;
-            if(typeof callback === "function")
-                return callback();
-        }
-    };
+    if (now < NETDATA.options.auto_refresher_stop_until) {
+        NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
+            NETDATA.chartRefresher,
+            NETDATA.chartRefresherWaitTime()
+        );
 
-    NETDATA.gaugeAnimation = function(state, status) {
-        var speed = 32;
+        // console.log('chartRefresher() end2 will run in ' + NETDATA.chartRefresherWaitTime().toString() + ' ms');
+        return;
+    }
 
-        if(typeof status === 'boolean' && status === false)
-            speed = 1000000000;
-        else if(typeof status === 'number')
-            speed = status;
+    if (NETDATA.options.pause) {
+        // console.log('auto-refresher is paused');
+        NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
+            NETDATA.chartRefresher,
+            NETDATA.chartRefresherWaitTime()
+        );
 
-        // console.log('gauge speed ' + speed);
-        state.tmp.gauge_instance.animationSpeed = speed;
-        state.tmp.___gaugeOld__.speed = speed;
-    };
+        // console.log('chartRefresher() end3 will run in ' + NETDATA.chartRefresherWaitTime().toString() + ' ms');
+        return;
+    }
 
-    NETDATA.gaugeSet = function(state, value, min, max) {
-        if(typeof value !== 'number') value = 0;
-        if(typeof min !== 'number') min = 0;
-        if(typeof max !== 'number') max = 0;
-        if(value > max) max = value;
-        if(value < min) min = value;
-        if(min > max) {
-            var t = min;
-            min = max;
-            max = t;
-        }
-        else if(min === max)
-            max = min + 1;
-
-        state.legendFormatValueDecimalsFromMinMax(min, max);
-
-        // gauge.js has an issue if the needle
-        // is smaller than min or larger than max
-        // when we set the new values
-        // the needle will go crazy
-
-        // to prevent it, we always feed it
-        // with a percentage, so that the needle
-        // is always between min and max
-        var pcent = (value - min) * 100 / (max - min);
-
-        // bug fix for gauge.js 1.3.1
-        // if the value is the absolute min or max, the chart is broken
-        if(pcent < 0.001) pcent = 0.001;
-        if(pcent > 99.999) pcent = 99.999;
-
-        state.tmp.gauge_instance.set(pcent);
-        // console.log('gauge set ' + pcent + ', value ' + value + ', min ' + min + ', max ' + max);
-
-        state.tmp.___gaugeOld__.value = value;
-        state.tmp.___gaugeOld__.min = min;
-        state.tmp.___gaugeOld__.max = max;
-    };
+    if (typeof NETDATA.options.pauseCallback === 'function') {
+        // console.log('auto-refresher is calling pauseCallback');
 
-    NETDATA.gaugeSetLabels = function(state, value, min, max) {
-        if(state.tmp.___gaugeOld__.valueLabel !== value) {
-            state.tmp.___gaugeOld__.valueLabel = value;
-            state.tmp.gaugeChartLabel.innerText = state.legendFormatValue(value);
-        }
-        if(state.tmp.___gaugeOld__.minLabel !== min) {
-            state.tmp.___gaugeOld__.minLabel = min;
-            state.tmp.gaugeChartMin.innerText = state.legendFormatValue(min);
-        }
-        if(state.tmp.___gaugeOld__.maxLabel !== max) {
-            state.tmp.___gaugeOld__.maxLabel = max;
-            state.tmp.gaugeChartMax.innerText = state.legendFormatValue(max);
-        }
-    };
+        NETDATA.options.pause = true;
+        NETDATA.options.pauseCallback();
+        NETDATA.chartRefresher();
 
-    NETDATA.gaugeClearSelection = function(state, force) {
-        if(typeof state.tmp.gaugeEvent !== 'undefined' && typeof state.tmp.gaugeEvent.timer !== 'undefined') {
-            NETDATA.timeout.clear(state.tmp.gaugeEvent.timer);
-            state.tmp.gaugeEvent.timer = undefined;
-        }
+        // console.log('chartRefresher() end4 (nested)');
+        return;
+    }
 
-        if(state.isAutoRefreshable() === true && state.data !== null && force !== true) {
-            NETDATA.gaugeChartUpdate(state, state.data);
-        }
-        else {
-            NETDATA.gaugeAnimation(state, false);
-            NETDATA.gaugeSetLabels(state, null, null, null);
-            NETDATA.gaugeSet(state, null, null, null);
-        }
+    if (NETDATA.options.current.parallel_refresher === false) {
+        // console.log('auto-refresher is calling chartRefresherNoParallel(0)');
+        NETDATA.chartRefresherNoParallel(0, function () {
+            NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
+                NETDATA.chartRefresher,
+                NETDATA.options.current.idle_between_loops
+            );
+        });
+        // console.log('chartRefresher() end5 (no parallel, nested)');
+        return;
+    }
 
-        NETDATA.gaugeAnimation(state, true);
-        return true;
-    };
+    if (NETDATA.options.updated_dom) {
+        // the dom has been updated
+        // get the dom parts again
+        // console.log('auto-refresher is calling parseDom()');
+        NETDATA.parseDom(NETDATA.chartRefresher);
+        // console.log('chartRefresher() end6 (parseDom)');
+        return;
+    }
 
-    NETDATA.gaugeSetSelection = function(state, t) {
-        if(state.timeIsVisible(t) !== true)
-            return NETDATA.gaugeClearSelection(state, true);
+    if (NETDATA.globalSelectionSync.active() === false) {
+        let parallel = [];
+        let targets = NETDATA.intersectionObserver.targets();
+        let len = targets.length;
+        let state;
+        while (len--) {
+            state = targets[len];
+            if (state.running || state.isVisible() === false) {
+                continue;
+            }
 
-        var slot = state.calculateRowForTime(t);
-        if(slot < 0 || slot >= state.data.result.length)
-            return NETDATA.gaugeClearSelection(state, true);
+            if (state.library.initialized === false) {
+                if (state.library.enabled) {
+                    state.library.initialize(NETDATA.chartRefresher);
+                    //console.log('chartRefresher() end6 (library init)');
+                    return;
+                }
+                else {
+                    state.error('chart library "' + state.library_name + '" is not enabled.');
+                }
+            }
 
-        if(typeof state.tmp.gaugeEvent === 'undefined') {
-            state.tmp.gaugeEvent = {
-                timer: undefined,
-                value: 0,
-                min: 0,
-                max: 0
-            };
+            if (NETDATA.scrollUp) {
+                parallel.unshift(state);
+            } else {
+                parallel.push(state);
+            }
         }
 
-        var value = state.data.result[state.data.result.length - 1 - slot];
-        var min = (state.tmp.gaugeMin === null)?NETDATA.commonMin.get(state):state.tmp.gaugeMin;
-        var max = (state.tmp.gaugeMax === null)?NETDATA.commonMax.get(state):state.tmp.gaugeMax;
+        len = parallel.length;
+        while (len--) {
+            state = parallel[len];
+            // console.log('auto-refresher executing in parallel for ' + parallel.length.toString() + ' charts');
+            // this will execute the jobs in parallel
 
-        // make sure it is zero based
-        // but only if it has not been set by the user
-        if(state.tmp.gaugeMin === null && min > 0) min = 0;
-        if(state.tmp.gaugeMax === null && max < 0) max = 0;
+            if (state.running === false) {
+                NETDATA.timeout.set(state.autoRefresh, 0);
+            }
+        }
+        //else {
+        //    console.log('auto-refresher nothing to do');
+        //}
+    }
 
-        state.tmp.gaugeEvent.value = value;
-        state.tmp.gaugeEvent.min = min;
-        state.tmp.gaugeEvent.max = max;
-        NETDATA.gaugeSetLabels(state, value, min, max);
+    // run the next refresh iteration
+    NETDATA.chartRefresherTimeoutId = NETDATA.timeout.set(
+        NETDATA.chartRefresher,
+        NETDATA.chartRefresherWaitTime()
+    );
 
-        if(state.tmp.gaugeEvent.timer === undefined) {
-            NETDATA.gaugeAnimation(state, false);
+    //console.log('chartRefresher() completed in ' + (Date.now() - now).toString() + ' ms');
+};
 
-            state.tmp.gaugeEvent.timer = NETDATA.timeout.set(function() {
-                state.tmp.gaugeEvent.timer = undefined;
-                NETDATA.gaugeSet(state, state.tmp.gaugeEvent.value, state.tmp.gaugeEvent.min, state.tmp.gaugeEvent.max);
-            }, 0);
-        }
+NETDATA.parseDom = function (callback) {
+    //console.log('parseDom()');
 
-        return true;
-    };
+    NETDATA.options.last_page_scroll = Date.now();
+    NETDATA.options.updated_dom = false;
+    NETDATA.chartRefresherRunsAfterParseDom = 0;
 
-    NETDATA.gaugeChartUpdate = function(state, data) {
-        var value, min, max;
+    let targets = $('div[data-netdata]'); //.filter(':visible');
 
-        if(NETDATA.globalPanAndZoom.isActive() === true || state.isAutoRefreshable() === false) {
-            NETDATA.gaugeSetLabels(state, null, null, null);
-            state.tmp.gauge_instance.set(0);
-        }
-        else {
-            value = data.result[0];
-            min = (state.tmp.gaugeMin === null)?NETDATA.commonMin.get(state):state.tmp.gaugeMin;
-            max = (state.tmp.gaugeMax === null)?NETDATA.commonMax.get(state):state.tmp.gaugeMax;
-            if(value < min) min = value;
-            if(value > max) max = value;
+    if (NETDATA.options.debug.main_loop) {
+        console.log('DOM updated - there are ' + targets.length + ' charts on page.');
+    }
 
-            // make sure it is zero based
-            // but only if it has not been set by the user
-            if(state.tmp.gaugeMin === null && min > 0) min = 0;
-            if(state.tmp.gaugeMax === null && max < 0) max = 0;
+    NETDATA.intersectionObserver.globalReset();
+    NETDATA.options.targets = [];
+    let len = targets.length;
+    while (len--) {
+        // the initialization will take care of sizing
+        // and the "loading..." message
+        let state = NETDATA.chartState(targets[len]);
+        NETDATA.options.targets.push(state);
+        NETDATA.intersectionObserver.observe(state);
+    }
 
-            NETDATA.gaugeSet(state, value, min, max);
-            NETDATA.gaugeSetLabels(state, value, min, max);
-        }
+    if (NETDATA.globalChartUnderlay.isActive()) {
+        NETDATA.globalChartUnderlay.setup();
+    } else {
+        NETDATA.globalChartUnderlay.clear();
+    }
 
-        return true;
-    };
+    if (typeof callback === 'function') {
+        return callback();
+    }
+};
 
-    NETDATA.gaugeChartCreate = function(state, data) {
-        // var chart = $(state.element_chart);
+// this is the main function - where everything starts
+NETDATA.started = false;
+NETDATA.start = function () {
+    // this should be called only once
 
-        var value = data.result[0];
-        var min = NETDATA.dataAttribute(state.element, 'gauge-min-value', null);
-        var max = NETDATA.dataAttribute(state.element, 'gauge-max-value', null);
-        // var adjust = NETDATA.dataAttribute(state.element, 'gauge-adjust', null);
-        var pointerColor = NETDATA.dataAttribute(state.element, 'gauge-pointer-color', NETDATA.themes.current.gauge_pointer);
-        var strokeColor = NETDATA.dataAttribute(state.element, 'gauge-stroke-color', NETDATA.themes.current.gauge_stroke);
-        var startColor = NETDATA.dataAttribute(state.element, 'gauge-start-color', state.chartCustomColors()[0]);
-        var stopColor = NETDATA.dataAttribute(state.element, 'gauge-stop-color', void 0);
-        var generateGradient = NETDATA.dataAttribute(state.element, 'gauge-generate-gradient', false);
+    if (NETDATA.started) {
+        console.log('netdata is already started');
+        return;
+    }
+
+    NETDATA.started = true;
+    NETDATA.options.page_is_visible = true;
 
-        if(min === null) {
-            min = NETDATA.commonMin.get(state);
-            state.tmp.gaugeMin = null;
+    $(window).blur(function () {
+        if (NETDATA.options.current.stop_updates_when_focus_is_lost) {
+            NETDATA.options.page_is_visible = false;
+            if (NETDATA.options.debug.focus) {
+                console.log('Lost Focus!');
+            }
         }
-        else
-            state.tmp.gaugeMin = min;
+    });
 
-        if(max === null) {
-            max = NETDATA.commonMax.get(state);
-            state.tmp.gaugeMax = null;
+    $(window).focus(function () {
+        if (NETDATA.options.current.stop_updates_when_focus_is_lost) {
+            NETDATA.options.page_is_visible = true;
+            if (NETDATA.options.debug.focus) {
+                console.log('Focus restored!');
+            }
         }
-        else
-            state.tmp.gaugeMax = max;
+    });
 
-        // make sure it is zero based
-        // but only if it has not been set by the user
-        if(state.tmp.gaugeMin === null && min > 0) min = 0;
-        if(state.tmp.gaugeMax === null && max < 0) max = 0;
-
-        var width = state.chartWidth(), height = state.chartHeight(); //, ratio = 1.5;
-        // console.log('gauge width: ' + width.toString() + ', height: ' + height.toString());
-        //switch(adjust) {
-        //  case 'width': width = height * ratio; break;
-        //  case 'height':
-        //  default: height = width / ratio; break;
-        //}
-        //state.element.style.width = width.toString() + 'px';
-        //state.element.style.height = height.toString() + 'px';
-
-        var lum_d = 0.05;
-
-        var options = {
-            lines: 12,                  // The number of lines to draw
-            angle: 0.14,                // The span of the gauge arc
-            lineWidth: 0.57,            // The line thickness
-            radiusScale: 1.0,           // Relative radius
-            pointer: {
-                length: 0.85,           // 0.9 The radius of the inner circle
-                strokeWidth: 0.045,     // The rotation offset
-                color: pointerColor     // Fill color
-            },
-            limitMax: true,             // If false, the max value of the gauge will be updated if value surpass max
-            limitMin: true,             // If true, the min value of the gauge will be fixed unless you set it manually
-            colorStart: startColor,     // Colors
-            colorStop: stopColor,       // just experiment with them
-            strokeColor: strokeColor,   // to see which ones work best for you
-            generateGradient: (generateGradient === true),
-            gradientType: 0,
-            highDpiSupport: true        // High resolution support
-        };
+    if (typeof document.hasFocus === 'function' && !document.hasFocus()) {
+        if (NETDATA.options.current.stop_updates_when_focus_is_lost) {
+            NETDATA.options.page_is_visible = false;
+            if (NETDATA.options.debug.focus) {
+                console.log('Document has no focus!');
+            }
+        }
+    }
 
-        if (generateGradient.constructor === Array) {
-            // example options:
-            // data-gauge-generate-gradient="[0, 50, 100]"
-            // data-gauge-gradient-percent-color-0="#FFFFFF"
-            // data-gauge-gradient-percent-color-50="#999900"
-            // data-gauge-gradient-percent-color-100="#000000"
-
-            options.percentColors = [];
-            var len = generateGradient.length;
-            while(len--) {
-                var pcent = generateGradient[len];
-                var color = NETDATA.dataAttribute(state.element, 'gauge-gradient-percent-color-' + pcent.toString(), false);
-                if(color !== false) {
-                    var a = [];
-                    a[0] = pcent / 100;
-                    a[1] = color;
-                    options.percentColors.unshift(a);
-                }
-            }
-            if(options.percentColors.length === 0)
-                delete options.percentColors;
-        }
-        else if(generateGradient === false && NETDATA.themes.current.gauge_gradient === true) {
-            //noinspection PointlessArithmeticExpressionJS
-            options.percentColors = [
-                [0.0, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 0))],
-                [0.1, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 1))],
-                [0.2, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 2))],
-                [0.3, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 3))],
-                [0.4, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 4))],
-                [0.5, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 5))],
-                [0.6, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 6))],
-                [0.7, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 7))],
-                [0.8, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 8))],
-                [0.9, NETDATA.colorLuminance(startColor, (lum_d * 10) - (lum_d * 9))],
-                [1.0, NETDATA.colorLuminance(startColor, 0.0)]];
-        }
-
-        state.tmp.gauge_canvas = document.createElement('canvas');
-        state.tmp.gauge_canvas.id = 'gauge-' + state.uuid + '-canvas';
-        state.tmp.gauge_canvas.className = 'gaugeChart';
-        state.tmp.gauge_canvas.width  = width;
-        state.tmp.gauge_canvas.height = height;
-        state.element_chart.appendChild(state.tmp.gauge_canvas);
-
-        var valuefontsize = Math.floor(height / 5);
-        var valuetop = Math.round((height - valuefontsize) / 3.2);
-        state.tmp.gaugeChartLabel = document.createElement('span');
-        state.tmp.gaugeChartLabel.className = 'gaugeChartLabel';
-        state.tmp.gaugeChartLabel.style.fontSize = valuefontsize + 'px';
-        state.tmp.gaugeChartLabel.style.top = valuetop.toString() + 'px';
-        state.element_chart.appendChild(state.tmp.gaugeChartLabel);
-
-        var titlefontsize = Math.round(valuefontsize / 2.1);
-        var titletop = 0;
-        state.tmp.gaugeChartTitle = document.createElement('span');
-        state.tmp.gaugeChartTitle.className = 'gaugeChartTitle';
-        state.tmp.gaugeChartTitle.innerText = state.title;
-        state.tmp.gaugeChartTitle.style.fontSize = titlefontsize + 'px';
-        state.tmp.gaugeChartTitle.style.lineHeight = titlefontsize + 'px';
-        state.tmp.gaugeChartTitle.style.top = titletop.toString() + 'px';
-        state.element_chart.appendChild(state.tmp.gaugeChartTitle);
-
-        var unitfontsize = Math.round(titlefontsize * 0.9);
-        state.tmp.gaugeChartUnits = document.createElement('span');
-        state.tmp.gaugeChartUnits.className = 'gaugeChartUnits';
-        state.tmp.gaugeChartUnits.innerText = state.units_current;
-        state.tmp.gaugeChartUnits.style.fontSize = unitfontsize + 'px';
-        state.element_chart.appendChild(state.tmp.gaugeChartUnits);
-
-        state.tmp.gaugeChartMin = document.createElement('span');
-        state.tmp.gaugeChartMin.className = 'gaugeChartMin';
-        state.tmp.gaugeChartMin.style.fontSize = Math.round(valuefontsize * 0.75).toString() + 'px';
-        state.element_chart.appendChild(state.tmp.gaugeChartMin);
-
-        state.tmp.gaugeChartMax = document.createElement('span');
-        state.tmp.gaugeChartMax.className = 'gaugeChartMax';
-        state.tmp.gaugeChartMax.style.fontSize = Math.round(valuefontsize * 0.75).toString() + 'px';
-        state.element_chart.appendChild(state.tmp.gaugeChartMax);
-
-        // when we just re-create the chart
-        // do not animate the first update
-        var animate = true;
-        if(typeof state.tmp.gauge_instance !== 'undefined')
-            animate = false;
-
-        state.tmp.gauge_instance = new Gauge(state.tmp.gauge_canvas).setOptions(options); // create sexy gauge!
-
-        state.tmp.___gaugeOld__ = {
-            value: value,
-            min: min,
-            max: max,
-            valueLabel: null,
-            minLabel: null,
-            maxLabel: null
-        };
+    // bootstrap tab switching
+    $('a[data-toggle="tab"]').on('shown.bs.tab', NETDATA.onscroll);
 
-        // we will always feed a percentage
-        state.tmp.gauge_instance.minValue = 0;
-        state.tmp.gauge_instance.maxValue = 100;
+    // bootstrap modal switching
+    let $modal = $('.modal');
+    $modal.on('hidden.bs.modal', NETDATA.onscroll);
+    $modal.on('shown.bs.modal', NETDATA.onscroll);
 
-        NETDATA.gaugeAnimation(state, animate);
-        NETDATA.gaugeSet(state, value, min, max);
-        NETDATA.gaugeSetLabels(state, value, min, max);
-        NETDATA.gaugeAnimation(state, true);
+    // bootstrap collapse switching
+    let $collapse = $('.collapse');
+    $collapse.on('hidden.bs.collapse', NETDATA.onscroll);
+    $collapse.on('shown.bs.collapse', NETDATA.onscroll);
 
-        state.legendSetUnitsString = function(units) {
-            if(typeof state.tmp.gaugeChartUnits !== 'undefined' && state.tmp.units !== units) {
-                state.tmp.gaugeChartUnits.innerText = units;
-                state.tmp.___gaugeOld__.valueLabel = null;
-                state.tmp.___gaugeOld__.minLabel = null;
-                state.tmp.___gaugeOld__.maxLabel = null;
-                state.tmp.units = units;
-            }
-        };
-        state.legendShowUndefined = function() {
-            if(typeof state.tmp.gauge_instance !== 'undefined')
-                NETDATA.gaugeClearSelection(state);
-        };
+    NETDATA.parseDom(NETDATA.chartRefresher);
 
-        return true;
-    };
+    // Alarms initialization
+    setTimeout(NETDATA.alarms.init, 1000);
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Charts Libraries Registration
-
-    NETDATA.chartLibraries = {
-        "dygraph": {
-            initialize: NETDATA.dygraphInitialize,
-            create: NETDATA.dygraphChartCreate,
-            update: NETDATA.dygraphChartUpdate,
-            resize: function(state) {
-                if(typeof state.tmp.dygraph_instance !== 'undefined' && typeof state.tmp.dygraph_instance.resize === 'function')
-                    state.tmp.dygraph_instance.resize();
-            },
-            setSelection: NETDATA.dygraphSetSelection,
-            clearSelection:  NETDATA.dygraphClearSelection,
-            toolboxPanAndZoom: NETDATA.dygraphToolboxPanAndZoom,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
-            format: function(state) { void(state); return 'json'; },
-            options: function(state) { return 'ms' + '%7C' + 'flip' + (this.isLogScale(state)?('%7C' + 'abs'):'').toString(); },
-            legend: function(state) {
-                return (this.isSparkline(state) === false && NETDATA.dataAttributeBoolean(state.element, 'legend', true) === true) ? 'right-side' : null;
-            },
-            autoresize: function(state) { void(state); return true; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return true; },
-            pixels_per_point: function(state) {
-                return (this.isSparkline(state) === false)?3:2;
-            },
-            isSparkline: function(state) {
-                if(typeof state.tmp.dygraph_sparkline === 'undefined') {
-                    state.tmp.dygraph_sparkline = (this.theme(state) === 'sparkline');
-                }
-                return state.tmp.dygraph_sparkline;
-            },
-            isLogScale: function(state) {
-                if(typeof state.tmp.dygraph_logscale === 'undefined') {
-                    state.tmp.dygraph_logscale = (this.theme(state) === 'logscale');
-                }
-                return state.tmp.dygraph_logscale;
-            },
-            theme: function(state) {
-                if(typeof state.tmp.dygraph_theme === 'undefined')
-                    state.tmp.dygraph_theme = NETDATA.dataAttribute(state.element, 'dygraph-theme', 'default');
-                return state.tmp.dygraph_theme;
-            },
-            container_class: function(state) {
-                if(this.legend(state) !== null)
-                    return 'netdata-container-with-legend';
-                return 'netdata-container';
+    // Registry initialization
+    setTimeout(NETDATA.registry.init, netdataRegistryAfterMs);
+
+    if (typeof netdataCallback === 'function') {
+        netdataCallback();
+    }
+};
+
+NETDATA.globalReset = function () {
+    NETDATA.intersectionObserver.globalReset();
+    NETDATA.globalSelectionSync.globalReset();
+    NETDATA.globalPanAndZoom.globalReset();
+    NETDATA.chartRegistry.globalReset();
+    NETDATA.commonMin.globalReset();
+    NETDATA.commonMax.globalReset();
+    NETDATA.commonColors.globalReset();
+    NETDATA.unitsConversion.globalReset();
+    NETDATA.options.targets = [];
+    NETDATA.parseDom();
+    NETDATA.unpause();
+};
+
+// Registry of netdata hosts
+
+NETDATA.alarms = {
+    onclick: null,                  // the callback to handle the click - it will be called with the alarm log entry
+    chart_div_offset: -50,          // give that space above the chart when scrolling to it
+    chart_div_id_prefix: 'chart_',  // the chart DIV IDs have this prefix (they should be NETDATA.name2id(chart.id))
+    chart_div_animation_duration: 0,// the duration of the animation while scrolling to a chart
+
+    ms_penalty: 0,                  // the time penalty of the next alarm
+    ms_between_notifications: 500,  // firefox moves the alarms off-screen (above, outside the top of the screen)
+                                    // if alarms are shown faster than: one per 500ms
+
+    update_every: 10000,            // the time in ms between alarm checks
+
+    notifications: false,           // when true, the browser supports notifications (may not be granted though)
+    last_notification_id: 0,        // the id of the last alarm_log we have raised an alarm for
+    first_notification_id: 0,       // the id of the first alarm_log entry for this session
+                                    // this is used to prevent CLEAR notifications for past events
+    // notifications_shown: [],
+
+    server: null,                   // the server to connect to for fetching alarms
+    current: null,                  // the list of raised alarms - updated in the background
+
+    // a callback function to call every time the list of raised alarms is refreshed
+    callback: (typeof netdataAlarmsActiveCallback === 'function') ? netdataAlarmsActiveCallback : null,
+
+    // a callback function to call every time a notification is shown
+    // the return value is used to decide if the notification will be shown
+    notificationCallback: (typeof netdataAlarmsNotifCallback === 'function') ? netdataAlarmsNotifCallback : null,
+
+    recipients: null,               // the list (array) of recipients to show alarms for, or null
+
+    recipientMatches: function (to_string, wanted_array) {
+        if (typeof wanted_array === 'undefined' || wanted_array === null || Array.isArray(wanted_array) === false) {
+            return true;
+        }
+
+        let r = ' ' + to_string.toString() + ' ';
+        let len = wanted_array.length;
+        while (len--) {
+            if (r.indexOf(' ' + wanted_array[len] + ' ') >= 0) {
+                return true;
             }
-        },
-        "sparkline": {
-            initialize: NETDATA.sparklineInitialize,
-            create: NETDATA.sparklineChartCreate,
-            update: NETDATA.sparklineChartUpdate,
-            resize: null,
-            setSelection: undefined, // function(state, t) { void(state); return true; },
-            clearSelection: undefined, // function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
-            format: function(state) { void(state); return 'array'; },
-            options: function(state) { void(state); return 'flip' + '%7C' + 'abs'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 3; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "peity": {
-            initialize: NETDATA.peityInitialize,
-            create: NETDATA.peityChartCreate,
-            update: NETDATA.peityChartUpdate,
-            resize: null,
-            setSelection: undefined, // function(state, t) { void(state); return true; },
-            clearSelection: undefined, // function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
-            format: function(state) { void(state); return 'ssvcomma'; },
-            options: function(state) { void(state); return 'null2zero' + '%7C' + 'flip' + '%7C' + 'abs'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 3; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "morris": {
-            initialize: NETDATA.morrisInitialize,
-            create: NETDATA.morrisChartCreate,
-            update: NETDATA.morrisChartUpdate,
-            resize: null,
-            setSelection: undefined, // function(state, t) { void(state); return true; },
-            clearSelection: undefined, // function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
-            format: function(state) { void(state); return 'json'; },
-            options: function(state) { void(state); return 'objectrows' + '%7C' + 'ms'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 50; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 15; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "google": {
-            initialize: NETDATA.googleInitialize,
-            create: NETDATA.googleChartCreate,
-            update: NETDATA.googleChartUpdate,
-            resize: null,
-            setSelection: undefined, //function(state, t) { void(state); return true; },
-            clearSelection: undefined, //function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result.rows$'),
-            format: function(state) { void(state); return 'datatable'; },
-            options: function(state) { void(state); return ''; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 300; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 4; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "raphael": {
-            initialize: NETDATA.raphaelInitialize,
-            create: NETDATA.raphaelChartCreate,
-            update: NETDATA.raphaelChartUpdate,
-            resize: null,
-            setSelection: undefined, // function(state, t) { void(state); return true; },
-            clearSelection: undefined, // function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
-            format: function(state) { void(state); return 'json'; },
-            options: function(state) { void(state); return ''; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 3; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "c3": {
-            initialize: NETDATA.c3Initialize,
-            create: NETDATA.c3ChartCreate,
-            update: NETDATA.c3ChartUpdate,
-            resize: null,
-            setSelection: undefined, // function(state, t) { void(state); return true; },
-            clearSelection: undefined, // function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
-            format: function(state) { void(state); return 'csvjsonarray'; },
-            options: function(state) { void(state); return 'milliseconds'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 15; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "d3pie": {
-            initialize: NETDATA.d3pieInitialize,
-            create: NETDATA.d3pieChartCreate,
-            update: NETDATA.d3pieChartUpdate,
-            resize: null,
-            setSelection: NETDATA.d3pieSetSelection,
-            clearSelection: NETDATA.d3pieClearSelection,
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
-            format: function(state) { void(state); return 'json'; },
-            options: function(state) { void(state); return 'objectrows' + '%7C' + 'ms'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 15; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "d3": {
-            initialize: NETDATA.d3Initialize,
-            create: NETDATA.d3ChartCreate,
-            update: NETDATA.d3ChartUpdate,
-            resize: null,
-            setSelection: undefined, // function(state, t) { void(state); return true; },
-            clearSelection: undefined, // function(state) { void(state); return true; },
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result.data$'),
-            format: function(state) { void(state); return 'json'; },
-            options: function(state) { void(state); return ''; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return false; },
-            pixels_per_point: function(state) { void(state); return 3; },
-            container_class: function(state) { void(state); return 'netdata-container'; }
-        },
-        "easypiechart": {
-            initialize: NETDATA.easypiechartInitialize,
-            create: NETDATA.easypiechartChartCreate,
-            update: NETDATA.easypiechartChartUpdate,
-            resize: null,
-            setSelection: NETDATA.easypiechartSetSelection,
-            clearSelection: NETDATA.easypiechartClearSelection,
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
-            format: function(state) { void(state); return 'array'; },
-            options: function(state) { void(state); return 'absolute'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return true; },
-            pixels_per_point: function(state) { void(state); return 3; },
-            aspect_ratio: 100,
-            container_class: function(state) { void(state); return 'netdata-container-easypiechart'; }
-        },
-        "gauge": {
-            initialize: NETDATA.gaugeInitialize,
-            create: NETDATA.gaugeChartCreate,
-            update: NETDATA.gaugeChartUpdate,
-            resize: null,
-            setSelection: NETDATA.gaugeSetSelection,
-            clearSelection: NETDATA.gaugeClearSelection,
-            toolboxPanAndZoom: null,
-            initialized: false,
-            enabled: true,
-            xssRegexIgnore: new RegExp('^/api/v1/data\.result$'),
-            format: function(state) { void(state); return 'array'; },
-            options: function(state) { void(state); return 'absolute'; },
-            legend: function(state) { void(state); return null; },
-            autoresize: function(state) { void(state); return false; },
-            max_updates_to_recreate: function(state) { void(state); return 5000; },
-            track_colors: function(state) { void(state); return true; },
-            pixels_per_point: function(state) { void(state); return 3; },
-            aspect_ratio: 60,
-            container_class: function(state) { void(state); return 'netdata-container-gauge'; }
         }
-    };
 
-    NETDATA.registerChartLibrary = function(library, url) {
-        if(NETDATA.options.debug.libraries === true)
-            console.log("registering chart library: " + library);
+        return false;
+    },
 
-        NETDATA.chartLibraries[library].url = url;
-        NETDATA.chartLibraries[library].initialized = true;
-        NETDATA.chartLibraries[library].enabled = true;
-    };
+    activeForRecipients: function () {
+        let active = {};
+        let data = NETDATA.alarms.current;
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Load required JS libraries and CSS
+        if (typeof data === 'undefined' || data === null) {
+            return active;
+        }
 
-    NETDATA.requiredJs = [
-        {
-            url: NETDATA.serverStatic + 'lib/bootstrap-3.3.7.min.js',
-            async: false,
-            isAlreadyLoaded: function() {
-                // check if bootstrap is loaded
-                if(typeof $().emulateTransitionEnd === 'function')
-                    return true;
-                else {
-                    return (typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap === true);
-                }
-            }
-        },
-        {
-            url: NETDATA.serverStatic + 'lib/fontawesome-all-5.0.1.min.js',
-            async: true,
-            isAlreadyLoaded: function() {
-                return (typeof netdataNoFontAwesome !== 'undefined' && netdataNoFontAwesome === true);
+        for (let x in data.alarms) {
+            if (!data.alarms.hasOwnProperty(x)) {
+                continue;
             }
-        },
-        {
-            url: NETDATA.serverStatic + 'lib/perfect-scrollbar-0.6.15.min.js',
-            isAlreadyLoaded: function() { return false; }
-        }
-    ];
 
-    NETDATA.requiredCSS = [
-        {
-            url: NETDATA.themes.current.bootstrap_css,
-            isAlreadyLoaded: function() {
-                return (typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap === true);
+            let alarm = data.alarms[x];
+            if ((alarm.status === 'WARNING' || alarm.status === 'CRITICAL') && NETDATA.alarms.recipientMatches(alarm.recipient, NETDATA.alarms.recipients)) {
+                active[x] = alarm;
             }
-        },
-        {
-            url: NETDATA.themes.current.dashboard_css,
-            isAlreadyLoaded: function() { return false; }
         }
-    ];
 
-    NETDATA.loadedRequiredJs = 0;
-    NETDATA.loadRequiredJs = function(index, callback) {
-        if(index >= NETDATA.requiredJs.length) {
-            if(typeof callback === 'function')
-                return callback();
-            return;
-        }
+        return active;
+    },
 
-        if(NETDATA.requiredJs[index].isAlreadyLoaded()) {
-            NETDATA.loadedRequiredJs++;
-            NETDATA.loadRequiredJs(++index, callback);
+    notify: function (entry) {
+        // console.log('alarm ' + entry.unique_id);
+
+        if (entry.updated) {
+            // console.log('alarm ' + entry.unique_id + ' has been updated by another alarm');
             return;
         }
 
-        if(NETDATA.options.debug.main_loop === true)
-            console.log('loading ' + NETDATA.requiredJs[index].url);
+        let value_string = entry.value_string;
 
-        var async = true;
-        if(typeof NETDATA.requiredJs[index].async !== 'undefined' && NETDATA.requiredJs[index].async === false)
-            async = false;
+        if (NETDATA.alarms.current !== null) {
+            // get the current value_string
+            let t = NETDATA.alarms.current.alarms[entry.chart + '.' + entry.name];
+            if (typeof t !== 'undefined' && entry.status === t.status && typeof t.value_string !== 'undefined') {
+                value_string = t.value_string;
+            }
+        }
 
-        $.ajax({
-            url: NETDATA.requiredJs[index].url,
-            cache: true,
-            dataType: "script",
-            xhrFields: { withCredentials: true } // required for the cookie
-        })
-        .done(function() {
-            if(NETDATA.options.debug.main_loop === true)
-                console.log('loaded ' + NETDATA.requiredJs[index].url);
-        })
-        .fail(function() {
-            alert('Cannot load required JS library: ' + NETDATA.requiredJs[index].url);
-        })
-        .always(function() {
-            NETDATA.loadedRequiredJs++;
+        let name = entry.name.replace(/_/g, ' ');
+        let status = entry.status.toLowerCase();
+        let title = name + ' = ' + value_string.toString();
+        let tag = entry.alarm_id;
+        let icon = 'images/seo-performance-128.png';
+        let interaction = false;
+        let data = entry;
+        let show = true;
 
-            if(async === false)
-                NETDATA.loadRequiredJs(++index, callback);
-        });
+        // console.log('alarm ' + entry.unique_id + ' ' + entry.chart + '.' + entry.name + ' is ' +  entry.status);
 
-        if(async === true)
-            NETDATA.loadRequiredJs(++index, callback);
-    };
+        switch (entry.status) {
+            case 'REMOVED':
+                show = false;
+                break;
 
-    NETDATA.loadRequiredCSS = function(index) {
-        if(index >= NETDATA.requiredCSS.length)
-            return;
+            case 'UNDEFINED':
+                return;
 
-        if(NETDATA.requiredCSS[index].isAlreadyLoaded()) {
-            NETDATA.loadRequiredCSS(++index);
-            return;
-        }
+            case 'UNINITIALIZED':
+                return;
 
-        if(NETDATA.options.debug.main_loop === true)
-            console.log('loading ' + NETDATA.requiredCSS[index].url);
+            case 'CLEAR':
+                if (entry.unique_id < NETDATA.alarms.first_notification_id) {
+                    // console.log('alarm ' + entry.unique_id + ' is not current');
+                    return;
+                }
+                if (entry.old_status === 'UNINITIALIZED' || entry.old_status === 'UNDEFINED') {
+                    // console.log('alarm' + entry.unique_id + ' switch to CLEAR from ' + entry.old_status);
+                    return;
+                }
+                if (entry.no_clear_notification) {
+                    // console.log('alarm' + entry.unique_id + ' is CLEAR but has no_clear_notification flag');
+                    return;
+                }
+                title = name + ' back to normal (' + value_string.toString() + ')';
+                icon = 'images/check-mark-2-128-green.png';
+                interaction = false;
+                break;
 
-        NETDATA._loadCSS(NETDATA.requiredCSS[index].url);
-        NETDATA.loadRequiredCSS(++index);
-    };
+            case 'WARNING':
+                if (entry.old_status === 'CRITICAL') {
+                    status = 'demoted to ' + entry.status.toLowerCase();
+                }
 
+                icon = 'images/alert-128-orange.png';
+                interaction = false;
+                break;
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Registry of netdata hosts
+            case 'CRITICAL':
+                if (entry.old_status === 'WARNING') {
+                    status = 'escalated to ' + entry.status.toLowerCase();
+                }
 
-    NETDATA.alarms = {
-        onclick: null,                  // the callback to handle the click - it will be called with the alarm log entry
-        chart_div_offset: -50,          // give that space above the chart when scrolling to it
-        chart_div_id_prefix: 'chart_',  // the chart DIV IDs have this prefix (they should be NETDATA.name2id(chart.id))
-        chart_div_animation_duration: 0,// the duration of the animation while scrolling to a chart
+                icon = 'images/alert-128-red.png';
+                interaction = true;
+                break;
 
-        ms_penalty: 0,                  // the time penalty of the next alarm
-        ms_between_notifications: 500,  // firefox moves the alarms off-screen (above, outside the top of the screen)
-                                        // if alarms are shown faster than: one per 500ms
+            default:
+                console.log('invalid alarm status ' + entry.status);
+                return;
+        }
 
-        update_every: 10000,            // the time in ms between alarm checks
+        // filter recipients
+        if (show) {
+            show = NETDATA.alarms.recipientMatches(entry.recipient, NETDATA.alarms.recipients);
+        }
 
-        notifications: false,           // when true, the browser supports notifications (may not be granted though)
-        last_notification_id: 0,        // the id of the last alarm_log we have raised an alarm for
-        first_notification_id: 0,       // the id of the first alarm_log entry for this session
-                                        // this is used to prevent CLEAR notifications for past events
-        // notifications_shown: [],
+        /*
+        // cleanup old notifications with the same alarm_id as this one
+        // it does not seem to work on any web browser - so notifications cannot be removed
 
-        server: null,                   // the server to connect to for fetching alarms
-        current: null,                  // the list of raised alarms - updated in the background
+        let len = NETDATA.alarms.notifications_shown.length;
+        while (len--) {
+            let n = NETDATA.alarms.notifications_shown[len];
+            if (n.data.alarm_id === entry.alarm_id) {
+                console.log('removing old alarm ' + n.data.unique_id);
 
-        // a callback function to call every time the list of raised alarms is refreshed
-        callback: (typeof netdataAlarmsActiveCallback === 'function')?netdataAlarmsActiveCallback:null,
+                // close the notification
+                n.close.bind(n);
 
-        // a callback function to call every time a notification is shown
-        // the return value is used to decide if the notification will be shown
-        notificationCallback: (typeof netdataAlarmsNotifCallback === 'function')?netdataAlarmsNotifCallback:null,
+                // remove it from the array
+                NETDATA.alarms.notifications_shown.splice(len, 1);
+                len = NETDATA.alarms.notifications_shown.length;
+            }
+        }
+        */
 
-        recipients: null,               // the list (array) of recipients to show alarms for, or null
+        if (show) {
+            if (typeof NETDATA.alarms.notificationCallback === 'function') {
+                show = NETDATA.alarms.notificationCallback(entry);
+            }
 
-        recipientMatches: function(to_string, wanted_array) {
-            if(typeof wanted_array === 'undefined' || wanted_array === null || Array.isArray(wanted_array) === false)
-                return true;
+            if (show) {
+                setTimeout(function () {
+                    // show this notification
+                    // console.log('new notification: ' + title);
+                    let n = new Notification(title, {
+                        body: entry.hostname + ' - ' + entry.chart + ' (' + entry.family + ') - ' + status + ': ' + entry.info,
+                        tag: tag,
+                        requireInteraction: interaction,
+                        icon: NETDATA.serverStatic + icon,
+                        data: data
+                    });
 
-            var r = ' ' + to_string.toString() + ' ';
-            var len = wanted_array.length;
-            while(len--) {
-                if(r.indexOf(' ' + wanted_array[len] + ' ') >= 0)
-                    return true;
-            }
+                    n.onclick = function (event) {
+                        event.preventDefault();
+                        NETDATA.alarms.onclick(event.target.data);
+                    };
 
-            return false;
-        },
+                    // console.log(n);
+                    // NETDATA.alarms.notifications_shown.push(n);
+                    // console.log(entry);
+                }, NETDATA.alarms.ms_penalty);
 
-        activeForRecipients: function() {
-            var active = {};
-            var data = NETDATA.alarms.current;
+                NETDATA.alarms.ms_penalty += NETDATA.alarms.ms_between_notifications;
+            }
+        }
+    },
 
-            if(typeof data === 'undefined' || data === null)
-                return active;
+    scrollToChart: function (chart_id) {
+        if (typeof chart_id === 'string') {
+            let offset = $('#' + NETDATA.alarms.chart_div_id_prefix + NETDATA.name2id(chart_id)).offset();
+            if (typeof offset !== 'undefined') {
+                $('html, body').animate({scrollTop: offset.top + NETDATA.alarms.chart_div_offset}, NETDATA.alarms.chart_div_animation_duration);
+                return true;
+            }
+        }
+        return false;
+    },
 
-            for(var x in data.alarms) {
-                if(!data.alarms.hasOwnProperty(x)) continue;
+    scrollToAlarm: function (alarm) {
+        if (typeof alarm === 'object') {
+            let ret = NETDATA.alarms.scrollToChart(alarm.chart);
 
-                var alarm = data.alarms[x];
-                if((alarm.status === 'WARNING' || alarm.status === 'CRITICAL') && NETDATA.alarms.recipientMatches(alarm.recipient, NETDATA.alarms.recipients))
-                    active[x] = alarm;
+            if (ret && NETDATA.options.page_is_visible === false) {
+                window.focus();
             }
+            //    alert('netdata dashboard will now scroll to chart: ' + alarm.chart + '\n\nThis alarm opened to bring the browser window in front of the screen. Click on the dashboard to prevent it from appearing again.');
+        }
 
-            return active;
-        },
+    },
 
-        notify: function(entry) {
-            // console.log('alarm ' + entry.unique_id);
+    notifyAll: function () {
+        // console.log('FETCHING ALARM LOG');
+        NETDATA.alarms.get_log(NETDATA.alarms.last_notification_id, function (data) {
+            // console.log('ALARM LOG FETCHED');
 
-            if(entry.updated === true) {
-                // console.log('alarm ' + entry.unique_id + ' has been updated by another alarm');
+            if (data === null || typeof data !== 'object') {
+                console.log('invalid alarms log response');
                 return;
             }
 
-            var value_string = entry.value_string;
-
-            if(NETDATA.alarms.current !== null) {
-                // get the current value_string
-                var t = NETDATA.alarms.current.alarms[entry.chart + '.' + entry.name];
-                if(typeof t !== 'undefined' && entry.status === t.status && typeof t.value_string !== 'undefined')
-                    value_string = t.value_string;
+            if (data.length === 0) {
+                console.log('received empty alarm log');
+                return;
             }
 
-            var name = entry.name.replace(/_/g, ' ');
-            var status = entry.status.toLowerCase();
-            var title = name + ' = ' + value_string.toString();
-            var tag = entry.alarm_id;
-            var icon = 'images/seo-performance-128.png';
-            var interaction = false;
-            var data = entry;
-            var show = true;
+            // console.log('received alarm log of ' + data.length + ' entries, from ' + data[data.length - 1].unique_id.toString() + ' to ' + data[0].unique_id.toString());
 
-            // console.log('alarm ' + entry.unique_id + ' ' + entry.chart + '.' + entry.name + ' is ' +  entry.status);
+            data.sort(function (a, b) {
+                if (a.unique_id > b.unique_id) {
+                    return -1;
+                }
+                if (a.unique_id < b.unique_id) {
+                    return 1;
+                }
+                return 0;
+            });
 
-            switch(entry.status) {
-                case 'REMOVED':
-                    show = false;
-                    break;
+            NETDATA.alarms.ms_penalty = 0;
 
-                case 'UNDEFINED':
-                    return;
+            let len = data.length;
+            while (len--) {
+                if (data[len].unique_id > NETDATA.alarms.last_notification_id) {
+                    NETDATA.alarms.notify(data[len]);
+                }
+                //else
+                //    console.log('ignoring alarm (older) with id ' + data[len].unique_id.toString());
+            }
 
-                case 'UNINITIALIZED':
-                    return;
+            NETDATA.alarms.last_notification_id = data[0].unique_id;
 
-                case 'CLEAR':
-                    if(entry.unique_id < NETDATA.alarms.first_notification_id) {
-                        // console.log('alarm ' + entry.unique_id + ' is not current');
-                        return;
-                    }
-                    if(entry.old_status === 'UNINITIALIZED' || entry.old_status === 'UNDEFINED') {
-                        // console.log('alarm' + entry.unique_id + ' switch to CLEAR from ' + entry.old_status);
-                        return;
-                    }
-                    if(entry.no_clear_notification === true) {
-                        // console.log('alarm' + entry.unique_id + ' is CLEAR but has no_clear_notification flag');
-                        return;
-                    }
-                    title = name + ' back to normal (' + value_string.toString() + ')';
-                    icon = 'images/check-mark-2-128-green.png';
-                    interaction = false;
-                    break;
-
-                case 'WARNING':
-                    if(entry.old_status === 'CRITICAL')
-                        status = 'demoted to ' + entry.status.toLowerCase();
-
-                    icon = 'images/alert-128-orange.png';
-                    interaction = false;
-                    break;
-
-                case 'CRITICAL':
-                    if(entry.old_status === 'WARNING')
-                        status = 'escalated to ' + entry.status.toLowerCase();
-                    
-                    icon = 'images/alert-128-red.png';
-                    interaction = true;
-                    break;
-
-                default:
-                    console.log('invalid alarm status ' + entry.status);
-                    return;
+            if (typeof netdataAlarmsRemember === 'undefined' || netdataAlarmsRemember) {
+                NETDATA.localStorageSet('last_notification_id', NETDATA.alarms.last_notification_id, null);
             }
+            // console.log('last notification id = ' + NETDATA.alarms.last_notification_id);
+        })
+    },
 
-            // filter recipients
-            if(show === true)
-                show = NETDATA.alarms.recipientMatches(entry.recipient, NETDATA.alarms.recipients);
+    check_notifications: function () {
+        // returns true if we should fire 1+ notifications
 
-            /*
-            // cleanup old notifications with the same alarm_id as this one
-            // it does not seem to work on any web browser - so notifications cannot be removed
+        if (NETDATA.alarms.notifications !== true) {
+            // console.log('web notifications are not available');
+            return false;
+        }
 
-            var len = NETDATA.alarms.notifications_shown.length;
-            while(len--) {
-                var n = NETDATA.alarms.notifications_shown[len];
-                if(n.data.alarm_id === entry.alarm_id) {
-                    console.log('removing old alarm ' + n.data.unique_id);
+        if (Notification.permission !== 'granted') {
+            // console.log('web notifications are not granted');
+            return false;
+        }
 
-                    // close the notification
-                    n.close.bind(n);
+        if (typeof NETDATA.alarms.current !== 'undefined' && typeof NETDATA.alarms.current.alarms === 'object') {
+            // console.log('can do alarms: old id = ' + NETDATA.alarms.last_notification_id + ' new id = ' + NETDATA.alarms.current.latest_alarm_log_unique_id);
 
-                    // remove it from the array
-                    NETDATA.alarms.notifications_shown.splice(len, 1);
-                    len = NETDATA.alarms.notifications_shown.length;
-                }
+            if (NETDATA.alarms.current.latest_alarm_log_unique_id > NETDATA.alarms.last_notification_id) {
+                // console.log('new alarms detected');
+                return true;
             }
-            */
-
-            if(show === true) {
-                if(typeof NETDATA.alarms.notificationCallback === 'function')
-                    show = NETDATA.alarms.notificationCallback(entry);
-
-                if(show === true) {
-                    setTimeout(function() {
-                        // show this notification
-                        // console.log('new notification: ' + title);
-                        var n = new Notification(title, {
-                            body: entry.hostname + ' - ' + entry.chart + ' (' + entry.family + ') - ' + status + ': ' + entry.info,
-                            tag: tag,
-                            requireInteraction: interaction,
-                            icon: NETDATA.serverStatic + icon,
-                            data: data
-                        });
+            //else console.log('no new alarms');
+        }
+        // else console.log('cannot process alarms');
 
-                        n.onclick = function(event) {
-                            event.preventDefault();
-                            NETDATA.alarms.onclick(event.target.data);
-                        };
+        return false;
+    },
 
-                        // console.log(n);
-                        // NETDATA.alarms.notifications_shown.push(n);
-                        // console.log(entry);
-                    }, NETDATA.alarms.ms_penalty);
+    get: function (what, callback) {
+        $.ajax({
+            url: NETDATA.alarms.server + '/api/v1/alarms?' + what.toString(),
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkOptional('/api/v1/alarms', data /*, '.*\.(calc|calc_parsed|warn|warn_parsed|crit|crit_parsed)$' */);
 
-                    NETDATA.alarms.ms_penalty += NETDATA.alarms.ms_between_notifications;
+                if (NETDATA.alarms.first_notification_id === 0 && typeof data.latest_alarm_log_unique_id === 'number') {
+                    NETDATA.alarms.first_notification_id = data.latest_alarm_log_unique_id;
                 }
-            }
-        },
 
-        scrollToChart: function(chart_id) {
-            if(typeof chart_id === 'string') {
-                var offset = $('#' + NETDATA.alarms.chart_div_id_prefix + NETDATA.name2id(chart_id)).offset();
-                if(typeof offset !== 'undefined') {
-                    $('html, body').animate({ scrollTop: offset.top + NETDATA.alarms.chart_div_offset }, NETDATA.alarms.chart_div_animation_duration);
-                    return true;
+                if (typeof callback === 'function') {
+                    return callback(data);
                 }
-            }
-            return false;
-        },
+            })
+            .fail(function () {
+                NETDATA.error(415, NETDATA.alarms.server);
 
-        scrollToAlarm: function(alarm) {
-            if(typeof alarm === 'object') {
-                var ret = NETDATA.alarms.scrollToChart(alarm.chart);
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    },
 
-                if(ret === true && NETDATA.options.page_is_visible === false)
-                    window.focus();
-                //    alert('netdata dashboard will now scroll to chart: ' + alarm.chart + '\n\nThis alarm opened to bring the browser window in front of the screen. Click on the dashboard to prevent it from appearing again.');
-            }
+    update_forever: function () {
+        if (netdataShowAlarms !== true || netdataSnapshotData !== null) {
+            return;
+        }
 
-        },
+        NETDATA.alarms.get('active', function (data) {
+            if (data !== null) {
+                NETDATA.alarms.current = data;
 
-        notifyAll: function() {
-            // console.log('FETCHING ALARM LOG');
-            NETDATA.alarms.get_log(NETDATA.alarms.last_notification_id, function(data) {
-                // console.log('ALARM LOG FETCHED');
+                if (NETDATA.alarms.check_notifications()) {
+                    NETDATA.alarms.notifyAll();
+                }
 
-                if(data === null || typeof data !== 'object') {
-                    console.log('invalid alarms log response');
-                    return;
+                if (typeof NETDATA.alarms.callback === 'function') {
+                    NETDATA.alarms.callback(data);
                 }
 
-                if(data.length === 0) {
-                    console.log('received empty alarm log');
+                // Health monitoring is disabled on this netdata
+                if (data.status === false) {
                     return;
                 }
+            }
 
-                // console.log('received alarm log of ' + data.length + ' entries, from ' + data[data.length - 1].unique_id.toString() + ' to ' + data[0].unique_id.toString());
+            setTimeout(NETDATA.alarms.update_forever, NETDATA.alarms.update_every);
+        });
+    },
 
-                data.sort(function(a, b) {
-                    if(a.unique_id > b.unique_id) return -1;
-                    if(a.unique_id < b.unique_id) return 1;
-                    return 0;
-                });
+    get_log: function (last_id, callback) {
+        // console.log('fetching all log after ' + last_id.toString());
+        $.ajax({
+            url: NETDATA.alarms.server + '/api/v1/alarm_log?after=' + last_id.toString(),
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkOptional('/api/v1/alarm_log', data);
 
-                NETDATA.alarms.ms_penalty = 0;
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
+            })
+            .fail(function () {
+                NETDATA.error(416, NETDATA.alarms.server);
 
-                var len = data.length;
-                while(len--) {
-                    if(data[len].unique_id > NETDATA.alarms.last_notification_id) {
-                        NETDATA.alarms.notify(data[len]);
-                    }
-                    //else
-                    //    console.log('ignoring alarm (older) with id ' + data[len].unique_id.toString());
+                if (typeof callback === 'function') {
+                    return callback(null);
                 }
+            });
+    },
 
-                NETDATA.alarms.last_notification_id = data[0].unique_id;
+    init: function () {
+        NETDATA.alarms.server = NETDATA.fixHost(NETDATA.serverDefault);
 
-                if(typeof netdataAlarmsRemember === 'undefined' || netdataAlarmsRemember === true)
-                    NETDATA.localStorageSet('last_notification_id', NETDATA.alarms.last_notification_id, null);
-                // console.log('last notification id = ' + NETDATA.alarms.last_notification_id);
-            })
-        },
+        if (typeof netdataAlarmsRemember === 'undefined' || netdataAlarmsRemember) {
+            NETDATA.alarms.last_notification_id =
+                NETDATA.localStorageGet('last_notification_id', NETDATA.alarms.last_notification_id, null);
+        }
 
-        check_notifications: function() {
-            // returns true if we should fire 1+ notifications
+        if (NETDATA.alarms.onclick === null) {
+            NETDATA.alarms.onclick = NETDATA.alarms.scrollToAlarm;
+        }
 
-            if(NETDATA.alarms.notifications !== true) {
-                // console.log('web notifications are not available');
-                return false;
-            }
+        if (typeof netdataAlarmsRecipients !== 'undefined' && Array.isArray(netdataAlarmsRecipients)) {
+            NETDATA.alarms.recipients = netdataAlarmsRecipients;
+        }
 
-            if(Notification.permission !== 'granted') {
-                // console.log('web notifications are not granted');
-                return false;
-            }
+        if (netdataShowAlarms) {
+            NETDATA.alarms.update_forever();
 
-            if(typeof NETDATA.alarms.current !== 'undefined' && typeof NETDATA.alarms.current.alarms === 'object') {
-                // console.log('can do alarms: old id = ' + NETDATA.alarms.last_notification_id + ' new id = ' + NETDATA.alarms.current.latest_alarm_log_unique_id);
+            if ('Notification' in window) {
+                // console.log('notifications available');
+                NETDATA.alarms.notifications = true;
 
-                if(NETDATA.alarms.current.latest_alarm_log_unique_id > NETDATA.alarms.last_notification_id) {
-                    // console.log('new alarms detected');
-                    return true;
+                if (Notification.permission === 'default') {
+                    Notification.requestPermission();
+                }
+            }
+        }
+    }
+};
+
+// Registry of netdata hosts
+
+NETDATA.registry = {
+    server: null,         // the netdata registry server
+    person_guid: null,    // the unique ID of this browser / user
+    machine_guid: null,   // the unique ID the netdata server that served dashboard.js
+    hostname: 'unknown',  // the hostname of the netdata server that served dashboard.js
+    machines: null,       // the user's other URLs
+    machines_array: null, // the user's other URLs in an array
+    person_urls: null,
+
+    parsePersonUrls: function (person_urls) {
+        // console.log(person_urls);
+        NETDATA.registry.person_urls = person_urls;
+
+        if (person_urls) {
+            NETDATA.registry.machines = {};
+            NETDATA.registry.machines_array = [];
+
+            let apu = person_urls;
+            let i = apu.length;
+            while (i--) {
+                if (typeof NETDATA.registry.machines[apu[i][0]] === 'undefined') {
+                    // console.log('adding: ' + apu[i][4] + ', ' + ((now - apu[i][2]) / 1000).toString());
+
+                    let obj = {
+                        guid: apu[i][0],
+                        url: apu[i][1],
+                        last_t: apu[i][2],
+                        accesses: apu[i][3],
+                        name: apu[i][4],
+                        alternate_urls: []
+                    };
+                    obj.alternate_urls.push(apu[i][1]);
+
+                    NETDATA.registry.machines[apu[i][0]] = obj;
+                    NETDATA.registry.machines_array.push(obj);
+                } else {
+                    // console.log('appending: ' + apu[i][4] + ', ' + ((now - apu[i][2]) / 1000).toString());
+
+                    let pu = NETDATA.registry.machines[apu[i][0]];
+                    if (pu.last_t < apu[i][2]) {
+                        pu.url = apu[i][1];
+                        pu.last_t = apu[i][2];
+                        pu.name = apu[i][4];
+                    }
+                    pu.accesses += apu[i][3];
+                    pu.alternate_urls.push(apu[i][1]);
                 }
-                //else console.log('no new alarms');
             }
-            // else console.log('cannot process alarms');
+        }
 
-            return false;
-        },
+        if (typeof netdataRegistryCallback === 'function') {
+            netdataRegistryCallback(NETDATA.registry.machines_array);
+        }
+    },
 
-        get: function(what, callback) {
-            $.ajax({
-                url: NETDATA.alarms.server + '/api/v1/alarms?' + what.toString(),
-                async: true,
-                cache: false,
-                headers: {
-                    'Cache-Control': 'no-cache, no-store',
-                    'Pragma': 'no-cache'
-                },
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-                .done(function(data) {
-                    data = NETDATA.xss.checkOptional('/api/v1/alarms', data /*, '.*\.(calc|calc_parsed|warn|warn_parsed|crit|crit_parsed)$' */);
+    init: function () {
+        if (netdataRegistry !== true) {
+            return;
+        }
 
-                    if(NETDATA.alarms.first_notification_id === 0 && typeof data.latest_alarm_log_unique_id === 'number')
-                        NETDATA.alarms.first_notification_id = data.latest_alarm_log_unique_id;
+        NETDATA.registry.hello(NETDATA.serverDefault, function (data) {
+            if (data) {
+                NETDATA.registry.server = data.registry;
+                NETDATA.registry.machine_guid = data.machine_guid;
+                NETDATA.registry.hostname = data.hostname;
 
-                    if(typeof callback === 'function')
-                        return callback(data);
-                })
-                .fail(function() {
-                    NETDATA.error(415, NETDATA.alarms.server);
+                NETDATA.registry.access(2, function (person_urls) {
+                    NETDATA.registry.parsePersonUrls(person_urls);
 
-                    if(typeof callback === 'function')
-                        return callback(null);
                 });
-        },
-
-        update_forever: function() {
-            if(netdataShowAlarms !== true || netdataSnapshotData !== null)
-                return;
-
-            NETDATA.alarms.get('active', function(data) {
-                if(data !== null) {
-                    NETDATA.alarms.current = data;
+            }
+        });
+    },
 
-                    if(NETDATA.alarms.check_notifications() === true) {
-                        NETDATA.alarms.notifyAll();
-                    }
+    hello: function (host, callback) {
+        host = NETDATA.fixHost(host);
 
-                    if (typeof NETDATA.alarms.callback === 'function') {
-                        NETDATA.alarms.callback(data);
-                    }
+        // send HELLO to a netdata server:
+        // 1. verifies the server is reachable
+        // 2. responds with the registry URL, the machine GUID of this netdata server and its hostname
+        $.ajax({
+            url: host + '/api/v1/registry?action=hello',
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkOptional('/api/v1/registry?action=hello', data);
 
-                    // Health monitoring is disabled on this netdata
-                    if(data.status === false) return;
+                if (typeof data.status !== 'string' || data.status !== 'ok') {
+                    NETDATA.error(408, host + ' response: ' + JSON.stringify(data));
+                    data = null;
                 }
 
-                setTimeout(NETDATA.alarms.update_forever, NETDATA.alarms.update_every);
-            });
-        },
-
-        get_log: function(last_id, callback) {
-            // console.log('fetching all log after ' + last_id.toString());
-            $.ajax({
-                url: NETDATA.alarms.server + '/api/v1/alarm_log?after=' + last_id.toString(),
-                async: true,
-                cache: false,
-                headers: {
-                    'Cache-Control': 'no-cache, no-store',
-                    'Pragma': 'no-cache'
-                },
-                xhrFields: { withCredentials: true } // required for the cookie
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
             })
-                .done(function(data) {
-                    data = NETDATA.xss.checkOptional('/api/v1/alarm_log', data);
-
-                    if(typeof callback === 'function')
-                        return callback(data);
-                })
-                .fail(function() {
-                    NETDATA.error(416, NETDATA.alarms.server);
-
-                    if(typeof callback === 'function')
-                        return callback(null);
-                });
-        },
-
-        init: function() {
-            NETDATA.alarms.server = NETDATA.fixHost(NETDATA.serverDefault);
-
-            if(typeof netdataAlarmsRemember === 'undefined' || netdataAlarmsRemember === true) {
-                NETDATA.alarms.last_notification_id =
-                    NETDATA.localStorageGet('last_notification_id', NETDATA.alarms.last_notification_id, null);
-            }
-
-            if(NETDATA.alarms.onclick === null)
-                NETDATA.alarms.onclick = NETDATA.alarms.scrollToAlarm;
+            .fail(function () {
+                NETDATA.error(407, host);
 
-            if(typeof netdataAlarmsRecipients !== 'undefined' && Array.isArray(netdataAlarmsRecipients))
-                NETDATA.alarms.recipients = netdataAlarmsRecipients;
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    },
+
+    access: function (max_redirects, callback) {
+        // send ACCESS to a netdata registry:
+        // 1. it lets it know we are accessing a netdata server (its machine GUID and its URL)
+        // 2. it responds with a list of netdata servers we know
+        // the registry identifies us using a cookie it sets the first time we access it
+        // the registry may respond with a redirect URL to send us to another registry
+        $.ajax({
+            url: NETDATA.registry.server + '/api/v1/registry?action=access&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault), // + '&visible_url=' + encodeURIComponent(document.location),
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkAlways('/api/v1/registry?action=access', data);
 
-            if(netdataShowAlarms === true) {
-                NETDATA.alarms.update_forever();
-            
-                if('Notification' in window) {
-                    // console.log('notifications available');
-                    NETDATA.alarms.notifications = true;
+                let redirect = null;
+                if (typeof data.registry === 'string') {
+                    redirect = data.registry;
+                }
 
-                    if(Notification.permission === 'default')
-                        Notification.requestPermission();
+                if (typeof data.status !== 'string' || data.status !== 'ok') {
+                    NETDATA.error(409, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
+                    data = null;
                 }
-            }
-        }
-    };
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Registry of netdata hosts
-
-    NETDATA.registry = {
-        server: null,         // the netdata registry server
-        person_guid: null,    // the unique ID of this browser / user
-        machine_guid: null,   // the unique ID the netdata server that served dashboard.js
-        hostname: 'unknown',  // the hostname of the netdata server that served dashboard.js
-        machines: null,       // the user's other URLs
-        machines_array: null, // the user's other URLs in an array
-        person_urls: null,
-
-        parsePersonUrls: function(person_urls) {
-            // console.log(person_urls);
-            NETDATA.registry.person_urls = person_urls;
-
-            if(person_urls) {
-                NETDATA.registry.machines = {};
-                NETDATA.registry.machines_array = [];
-
-                var apu = person_urls;
-                var i = apu.length;
-                while(i--) {
-                    if(typeof NETDATA.registry.machines[apu[i][0]] === 'undefined') {
-                        // console.log('adding: ' + apu[i][4] + ', ' + ((now - apu[i][2]) / 1000).toString());
-
-                        var obj = {
-                            guid: apu[i][0],
-                            url: apu[i][1],
-                            last_t: apu[i][2],
-                            accesses: apu[i][3],
-                            name: apu[i][4],
-                            alternate_urls: []
-                        };
-                        obj.alternate_urls.push(apu[i][1]);
-
-                        NETDATA.registry.machines[apu[i][0]] = obj;
-                        NETDATA.registry.machines_array.push(obj);
+                if (data === null) {
+                    if (redirect !== null && max_redirects > 0) {
+                        NETDATA.registry.server = redirect;
+                        NETDATA.registry.access(max_redirects - 1, callback);
                     }
                     else {
-                        // console.log('appending: ' + apu[i][4] + ', ' + ((now - apu[i][2]) / 1000).toString());
-
-                        var pu = NETDATA.registry.machines[apu[i][0]];
-                        if(pu.last_t < apu[i][2]) {
-                            pu.url = apu[i][1];
-                            pu.last_t = apu[i][2];
-                            pu.name = apu[i][4];
+                        if (typeof callback === 'function') {
+                            return callback(null);
                         }
-                        pu.accesses += apu[i][3];
-                        pu.alternate_urls.push(apu[i][1]);
                     }
                 }
-            }
+                else {
+                    if (typeof data.person_guid === 'string') {
+                        NETDATA.registry.person_guid = data.person_guid;
+                    }
 
-            if(typeof netdataRegistryCallback === 'function')
-                netdataRegistryCallback(NETDATA.registry.machines_array);
-        },
+                    if (typeof callback === 'function') {
+                        return callback(data.urls);
+                    }
+                }
+            })
+            .fail(function () {
+                NETDATA.error(410, NETDATA.registry.server);
+
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    },
 
-        init: function() {
-            if(netdataRegistry !== true) return;
+    delete: function (delete_url, callback) {
+        // send DELETE to a netdata registry:
+        $.ajax({
+            url: NETDATA.registry.server + '/api/v1/registry?action=delete&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&delete_url=' + encodeURIComponent(delete_url),
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkAlways('/api/v1/registry?action=delete', data);
 
-            NETDATA.registry.hello(NETDATA.serverDefault, function(data) {
-                if(data) {
-                    NETDATA.registry.server = data.registry;
-                    NETDATA.registry.machine_guid = data.machine_guid;
-                    NETDATA.registry.hostname = data.hostname;
+                if (typeof data.status !== 'string' || data.status !== 'ok') {
+                    NETDATA.error(411, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
+                    data = null;
+                }
 
-                    NETDATA.registry.access(2, function (person_urls) {
-                        NETDATA.registry.parsePersonUrls(person_urls);
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
+            })
+            .fail(function () {
+                NETDATA.error(412, NETDATA.registry.server);
 
-                    });
+                if (typeof callback === 'function') {
+                    return callback(null);
                 }
             });
-        },
-
-        hello: function(host, callback) {
-            host = NETDATA.fixHost(host);
+    },
 
-            // send HELLO to a netdata server:
-            // 1. verifies the server is reachable
-            // 2. responds with the registry URL, the machine GUID of this netdata server and its hostname
-            $.ajax({
-                    url: host + '/api/v1/registry?action=hello',
-                    async: true,
-                    cache: false,
-                    headers: {
-                        'Cache-Control': 'no-cache, no-store',
-                        'Pragma': 'no-cache'
-                    },
-                    xhrFields: { withCredentials: true } // required for the cookie
-                })
-                .done(function(data) {
-                    data = NETDATA.xss.checkOptional('/api/v1/registry?action=hello', data);
+    search: function (machine_guid, callback) {
+        // SEARCH for the URLs of a machine:
+        $.ajax({
+            url: NETDATA.registry.server + '/api/v1/registry?action=search&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&for=' + machine_guid,
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkAlways('/api/v1/registry?action=search', data);
 
-                    if(typeof data.status !== 'string' || data.status !== 'ok') {
-                        NETDATA.error(408, host + ' response: ' + JSON.stringify(data));
-                        data = null;
-                    }
+                if (typeof data.status !== 'string' || data.status !== 'ok') {
+                    NETDATA.error(417, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
+                    data = null;
+                }
 
-                    if(typeof callback === 'function')
-                        return callback(data);
-                })
-                .fail(function() {
-                    NETDATA.error(407, host);
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
+            })
+            .fail(function () {
+                NETDATA.error(418, NETDATA.registry.server);
 
-                    if(typeof callback === 'function')
-                        return callback(null);
-                });
-        },
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    },
 
-        access: function(max_redirects, callback) {
-            // send ACCESS to a netdata registry:
-            // 1. it lets it know we are accessing a netdata server (its machine GUID and its URL)
-            // 2. it responds with a list of netdata servers we know
-            // the registry identifies us using a cookie it sets the first time we access it
-            // the registry may respond with a redirect URL to send us to another registry
-            $.ajax({
-                    url: NETDATA.registry.server + '/api/v1/registry?action=access&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault), // + '&visible_url=' + encodeURIComponent(document.location),
-                    async: true,
-                    cache: false,
-                    headers: {
-                        'Cache-Control': 'no-cache, no-store',
-                        'Pragma': 'no-cache'
-                    },
-                    xhrFields: { withCredentials: true } // required for the cookie
-                })
-                .done(function(data) {
-                    data = NETDATA.xss.checkAlways('/api/v1/registry?action=access', data);
+    switch: function (new_person_guid, callback) {
+        // impersonate
+        $.ajax({
+            url: NETDATA.registry.server + '/api/v1/registry?action=switch&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&to=' + new_person_guid,
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkAlways('/api/v1/registry?action=switch', data);
 
-                    var redirect = null;
-                    if(typeof data.registry === 'string')
-                        redirect = data.registry;
+                if (typeof data.status !== 'string' || data.status !== 'ok') {
+                    NETDATA.error(413, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
+                    data = null;
+                }
 
-                    if(typeof data.status !== 'string' || data.status !== 'ok') {
-                        NETDATA.error(409, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
-                        data = null;
-                    }
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
+            })
+            .fail(function () {
+                NETDATA.error(414, NETDATA.registry.server);
 
-                    if(data === null) {
-                        if(redirect !== null && max_redirects > 0) {
-                            NETDATA.registry.server = redirect;
-                            NETDATA.registry.access(max_redirects - 1, callback);
-                        }
-                        else {
-                            if(typeof callback === 'function')
-                                return callback(null);
-                        }
-                    }
-                    else {
-                        if(typeof data.person_guid === 'string')
-                            NETDATA.registry.person_guid = data.person_guid;
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    }
+};
 
-                        if(typeof callback === 'function')
-                            return callback(data.urls);
-                    }
-                })
-                .fail(function() {
-                    NETDATA.error(410, NETDATA.registry.server);
+// Load required JS libraries and CSS
 
-                    if(typeof callback === 'function')
-                        return callback(null);
-                });
-        },
+NETDATA.requiredJs = [
+    {
+        url: NETDATA.serverStatic + 'lib/bootstrap-3.3.7.min.js',
+        async: false,
+        isAlreadyLoaded: function () {
+            // check if bootstrap is loaded
+            if (typeof $().emulateTransitionEnd === 'function') {
+                return true;
+            } else {
+                return typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap;
+            }
+        }
+    },
+    {
+        url: NETDATA.serverStatic + 'lib/fontawesome-all-5.0.1.min.js',
+        async: true,
+        isAlreadyLoaded: function () {
+            return typeof netdataNoFontAwesome !== 'undefined' && netdataNoFontAwesome;
+        }
+    },
+    {
+        url: NETDATA.serverStatic + 'lib/perfect-scrollbar-0.6.15.min.js',
+        isAlreadyLoaded: function () {
+            return false;
+        }
+    }
+];
+
+NETDATA.requiredCSS = [
+    {
+        url: NETDATA.themes.current.bootstrap_css,
+        isAlreadyLoaded: function () {
+            return typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap;
+        }
+    },
+    {
+        url: NETDATA.themes.current.dashboard_css,
+        isAlreadyLoaded: function () {
+            return false;
+        }
+    }
+];
 
-        delete: function(delete_url, callback) {
-            // send DELETE to a netdata registry:
-            $.ajax({
-                url: NETDATA.registry.server + '/api/v1/registry?action=delete&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&delete_url=' + encodeURIComponent(delete_url),
-                async: true,
-                cache: false,
-                headers: {
-                    'Cache-Control': 'no-cache, no-store',
-                    'Pragma': 'no-cache'
-                },
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-                .done(function(data) {
-                    data = NETDATA.xss.checkAlways('/api/v1/registry?action=delete', data);
+NETDATA.loadedRequiredJs = 0;
+NETDATA.loadRequiredJs = function (index, callback) {
+    if (index >= NETDATA.requiredJs.length) {
+        if (typeof callback === 'function') {
+            return callback();
+        }
+        return;
+    }
 
-                    if(typeof data.status !== 'string' || data.status !== 'ok') {
-                        NETDATA.error(411, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
-                        data = null;
-                    }
+    if (NETDATA.requiredJs[index].isAlreadyLoaded()) {
+        NETDATA.loadedRequiredJs++;
+        NETDATA.loadRequiredJs(++index, callback);
+        return;
+    }
 
-                    if(typeof callback === 'function')
-                        return callback(data);
-                })
-                .fail(function() {
-                    NETDATA.error(412, NETDATA.registry.server);
+    if (NETDATA.options.debug.main_loop) {
+        console.log('loading ' + NETDATA.requiredJs[index].url);
+    }
 
-                    if(typeof callback === 'function')
-                        return callback(null);
-                });
-        },
+    let async = true;
+    if (typeof NETDATA.requiredJs[index].async !== 'undefined' && NETDATA.requiredJs[index].async === false) {
+        async = false;
+    }
 
-        search: function(machine_guid, callback) {
-            // SEARCH for the URLs of a machine:
-            $.ajax({
-                url: NETDATA.registry.server + '/api/v1/registry?action=search&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&for=' + machine_guid,
-                async: true,
-                cache: false,
-                headers: {
-                    'Cache-Control': 'no-cache, no-store',
-                    'Pragma': 'no-cache'
-                },
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-                .done(function(data) {
-                    data = NETDATA.xss.checkAlways('/api/v1/registry?action=search', data);
+    $.ajax({
+        url: NETDATA.requiredJs[index].url,
+        cache: true,
+        dataType: "script",
+        xhrFields: {withCredentials: true} // required for the cookie
+    })
+        .done(function () {
+            if (NETDATA.options.debug.main_loop) {
+                console.log('loaded ' + NETDATA.requiredJs[index].url);
+            }
+        })
+        .fail(function () {
+            alert('Cannot load required JS library: ' + NETDATA.requiredJs[index].url);
+        })
+        .always(function () {
+            NETDATA.loadedRequiredJs++;
 
-                    if(typeof data.status !== 'string' || data.status !== 'ok') {
-                        NETDATA.error(417, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
-                        data = null;
-                    }
+            // if (async === false)
+            if (!async) {
+                NETDATA.loadRequiredJs(++index, callback);
+            }
+        });
 
-                    if(typeof callback === 'function')
-                        return callback(data);
-                })
-                .fail(function() {
-                    NETDATA.error(418, NETDATA.registry.server);
+    // if (async === true)
+    if (async) {
+        NETDATA.loadRequiredJs(++index, callback);
+    }
+};
 
-                    if(typeof callback === 'function')
-                        return callback(null);
-                });
-        },
+NETDATA.loadRequiredCSS = function (index) {
+    if (index >= NETDATA.requiredCSS.length) {
+        return;
+    }
 
-        switch: function(new_person_guid, callback) {
-            // impersonate
-            $.ajax({
-                url: NETDATA.registry.server + '/api/v1/registry?action=switch&machine=' + NETDATA.registry.machine_guid + '&name=' + encodeURIComponent(NETDATA.registry.hostname) + '&url=' + encodeURIComponent(NETDATA.serverDefault) + '&to=' + new_person_guid,
-                async: true,
-                cache: false,
-                headers: {
-                    'Cache-Control': 'no-cache, no-store',
-                    'Pragma': 'no-cache'
-                },
-                xhrFields: { withCredentials: true } // required for the cookie
-            })
-                .done(function(data) {
-                    data = NETDATA.xss.checkAlways('/api/v1/registry?action=switch', data);
+    if (NETDATA.requiredCSS[index].isAlreadyLoaded()) {
+        NETDATA.loadRequiredCSS(++index);
+        return;
+    }
 
-                    if(typeof data.status !== 'string' || data.status !== 'ok') {
-                        NETDATA.error(413, NETDATA.registry.server + ' responded with: ' + JSON.stringify(data));
-                        data = null;
-                    }
+    if (NETDATA.options.debug.main_loop) {
+        console.log('loading ' + NETDATA.requiredCSS[index].url);
+    }
 
-                    if(typeof callback === 'function')
-                        return callback(data);
-                })
-                .fail(function() {
-                    NETDATA.error(414, NETDATA.registry.server);
+    NETDATA._loadCSS(NETDATA.requiredCSS[index].url);
+    NETDATA.loadRequiredCSS(++index);
+};
 
-                    if(typeof callback === 'function')
-                        return callback(null);
-                });
-        }
-    };
+// Boot it!
 
-    // ----------------------------------------------------------------------------------------------------------------
-    // Boot it!
+if (typeof netdataPrepCallback === 'function') {
+    netdataPrepCallback();
+}
 
-    if(typeof netdataPrepCallback === 'function')
-        netdataPrepCallback();
+NETDATA.errorReset();
+NETDATA.loadRequiredCSS(0);
 
-    NETDATA.errorReset();
-    NETDATA.loadRequiredCSS(0);
+NETDATA._loadjQuery(function () {
+    NETDATA.loadRequiredJs(0, function () {
+        if (typeof $().emulateTransitionEnd !== 'function') {
+            // bootstrap is not available
+            NETDATA.options.current.show_help = false;
+        }
 
-    NETDATA._loadjQuery(function() {
-        NETDATA.loadRequiredJs(0, function() {
-            if(typeof $().emulateTransitionEnd !== 'function') {
-                // bootstrap is not available
-                NETDATA.options.current.show_help = false;
+        if (typeof netdataDontStart === 'undefined' || !netdataDontStart) {
+            if (NETDATA.options.debug.main_loop) {
+                console.log('starting chart refresh thread');
             }
 
-            if(typeof netdataDontStart === 'undefined' || !netdataDontStart) {
-                if(NETDATA.options.debug.main_loop === true)
-                    console.log('starting chart refresh thread');
-
-                NETDATA.start();
-            }
-        });
+            NETDATA.start();
+        }
     });
+});
 })(window, document, (typeof jQuery === 'function')?jQuery:undefined);

web/gui/index.html

@@ -1072,9 +1072,9 @@
 
             if(!found) {
                 if(machines)
-                    el += '<li><a href="https://github.com/netdata/netdata/wiki/mynetdata-menu-item" style="color: #666;" target="_blank">your netdata server list is empty...</a></li>';
+                    el += '<li><a href="https://github.com/netdata/netdata/tree/master/registry#netdata-registry" style="color: #666;" target="_blank">your netdata server list is empty...</a></li>';
                 else
-                    el += '<li><a href="https://github.com/netdata/netdata/wiki/mynetdata-menu-item" style="color: #666;" target="_blank">failed to contact the registry...</a></li>';
+                    el += '<li><a href="https://github.com/netdata/netdata/tree/master/registry#netdata-registry" style="color: #666;" target="_blank">failed to contact the registry...</a></li>';
 
                 a1 += '<li><a href="#" onClick="return false;">&nbsp;</a></li>';
 
@@ -1101,7 +1101,7 @@
             el += '<li role="separator" class="divider"></li>';
             a1 += '<li role="separator" class="divider"></li>';
 
-            el += '<li><a href="https://github.com/netdata/netdata/wiki/mynetdata-menu-item" style="color: #999;" target="_blank">What is this?</a></li>';
+            el += '<li><a href="https://github.com/netdata/netdata/tree/master/registry#netdata-registry" style="color: #999;" target="_blank">What is this?</a></li>';
             a1 += '<li><a href="#" style="color: #999;" onclick="switchRegistryModalHandler(); return false;"><i class="fas fa-cog" style="color: #999;"></i></a></li>';
 
             document.getElementById('mynetdata_servers').innerHTML = el;
@@ -2184,7 +2184,7 @@
         function alarmsUpdateModal() {
             var active = '<h3>Raised Alarms</h3><table class="table">';
             var all = '<h3>All Running Alarms</h3><div class="panel-group" id="alarms_all_accordion" role="tablist" aria-multiselectable="true">';
-            var footer = '<hr/><a href="https://github.com/netdata/netdata/wiki/Generating-Badges" target="_blank">netdata badges</a> refresh automatically. Their color indicates the state of the alarm: <span style="color: #e05d44"><b>&nbsp;red&nbsp;</b></span> is critical, <span style="color:#fe7d37"><b>&nbsp;orange&nbsp;</b></span> is warning, <span style="color: #4c1"><b>&nbsp;bright green&nbsp;</b></span> is ok, <span style="color: #9f9f9f"><b>&nbsp;light grey&nbsp;</b></span> is undefined (i.e. no data or no status), <span style="color: #000"><b>&nbsp;black&nbsp;</b></span> is not initialized. You can copy and paste their URLs to embed them in any web page.<br/>netdata can send notifications for these alarms. Check <a href="https://github.com/netdata/netdata/blob/master/health/notifications/health_alarm_notify.conf">this configuration file</a> for more information.';
+            var footer = '<hr/><a href="https://github.com/netdata/netdata/tree/master/web/api/badges#netdata-badges" target="_blank">netdata badges</a> refresh automatically. Their color indicates the state of the alarm: <span style="color: #e05d44"><b>&nbsp;red&nbsp;</b></span> is critical, <span style="color:#fe7d37"><b>&nbsp;orange&nbsp;</b></span> is warning, <span style="color: #4c1"><b>&nbsp;bright green&nbsp;</b></span> is ok, <span style="color: #9f9f9f"><b>&nbsp;light grey&nbsp;</b></span> is undefined (i.e. no data or no status), <span style="color: #000"><b>&nbsp;black&nbsp;</b></span> is not initialized. You can copy and paste their URLs to embed them in any web page.<br/>netdata can send notifications for these alarms. Check <a href="https://github.com/netdata/netdata/blob/master/health/notifications/health_alarm_notify.conf">this configuration file</a> for more information.';
 
             loadClipboard(function() {});
 

web/gui/src/dashboard.js/alarms.js

@@ -0,0 +1,422 @@
+
+// Registry of netdata hosts
+
+NETDATA.alarms = {
+    onclick: null,                  // the callback to handle the click - it will be called with the alarm log entry
+    chart_div_offset: -50,          // give that space above the chart when scrolling to it
+    chart_div_id_prefix: 'chart_',  // the chart DIV IDs have this prefix (they should be NETDATA.name2id(chart.id))
+    chart_div_animation_duration: 0,// the duration of the animation while scrolling to a chart
+
+    ms_penalty: 0,                  // the time penalty of the next alarm
+    ms_between_notifications: 500,  // firefox moves the alarms off-screen (above, outside the top of the screen)
+                                    // if alarms are shown faster than: one per 500ms
+
+    update_every: 10000,            // the time in ms between alarm checks
+
+    notifications: false,           // when true, the browser supports notifications (may not be granted though)
+    last_notification_id: 0,        // the id of the last alarm_log we have raised an alarm for
+    first_notification_id: 0,       // the id of the first alarm_log entry for this session
+                                    // this is used to prevent CLEAR notifications for past events
+    // notifications_shown: [],
+
+    server: null,                   // the server to connect to for fetching alarms
+    current: null,                  // the list of raised alarms - updated in the background
+
+    // a callback function to call every time the list of raised alarms is refreshed
+    callback: (typeof netdataAlarmsActiveCallback === 'function') ? netdataAlarmsActiveCallback : null,
+
+    // a callback function to call every time a notification is shown
+    // the return value is used to decide if the notification will be shown
+    notificationCallback: (typeof netdataAlarmsNotifCallback === 'function') ? netdataAlarmsNotifCallback : null,
+
+    recipients: null,               // the list (array) of recipients to show alarms for, or null
+
+    recipientMatches: function (to_string, wanted_array) {
+        if (typeof wanted_array === 'undefined' || wanted_array === null || Array.isArray(wanted_array) === false) {
+            return true;
+        }
+
+        let r = ' ' + to_string.toString() + ' ';
+        let len = wanted_array.length;
+        while (len--) {
+            if (r.indexOf(' ' + wanted_array[len] + ' ') >= 0) {
+                return true;
+            }
+        }
+
+        return false;
+    },
+
+    activeForRecipients: function () {
+        let active = {};
+        let data = NETDATA.alarms.current;
+
+        if (typeof data === 'undefined' || data === null) {
+            return active;
+        }
+
+        for (let x in data.alarms) {
+            if (!data.alarms.hasOwnProperty(x)) {
+                continue;
+            }
+
+            let alarm = data.alarms[x];
+            if ((alarm.status === 'WARNING' || alarm.status === 'CRITICAL') && NETDATA.alarms.recipientMatches(alarm.recipient, NETDATA.alarms.recipients)) {
+                active[x] = alarm;
+            }
+        }
+
+        return active;
+    },
+
+    notify: function (entry) {
+        // console.log('alarm ' + entry.unique_id);
+
+        if (entry.updated) {
+            // console.log('alarm ' + entry.unique_id + ' has been updated by another alarm');
+            return;
+        }
+
+        let value_string = entry.value_string;
+
+        if (NETDATA.alarms.current !== null) {
+            // get the current value_string
+            let t = NETDATA.alarms.current.alarms[entry.chart + '.' + entry.name];
+            if (typeof t !== 'undefined' && entry.status === t.status && typeof t.value_string !== 'undefined') {
+                value_string = t.value_string;
+            }
+        }
+
+        let name = entry.name.replace(/_/g, ' ');
+        let status = entry.status.toLowerCase();
+        let title = name + ' = ' + value_string.toString();
+        let tag = entry.alarm_id;
+        let icon = 'images/seo-performance-128.png';
+        let interaction = false;
+        let data = entry;
+        let show = true;
+
+        // console.log('alarm ' + entry.unique_id + ' ' + entry.chart + '.' + entry.name + ' is ' +  entry.status);
+
+        switch (entry.status) {
+            case 'REMOVED':
+                show = false;
+                break;
+
+            case 'UNDEFINED':
+                return;
+
+            case 'UNINITIALIZED':
+                return;
+
+            case 'CLEAR':
+                if (entry.unique_id < NETDATA.alarms.first_notification_id) {
+                    // console.log('alarm ' + entry.unique_id + ' is not current');
+                    return;
+                }
+                if (entry.old_status === 'UNINITIALIZED' || entry.old_status === 'UNDEFINED') {
+                    // console.log('alarm' + entry.unique_id + ' switch to CLEAR from ' + entry.old_status);
+                    return;
+                }
+                if (entry.no_clear_notification) {
+                    // console.log('alarm' + entry.unique_id + ' is CLEAR but has no_clear_notification flag');
+                    return;
+                }
+                title = name + ' back to normal (' + value_string.toString() + ')';
+                icon = 'images/check-mark-2-128-green.png';
+                interaction = false;
+                break;
+
+            case 'WARNING':
+                if (entry.old_status === 'CRITICAL') {
+                    status = 'demoted to ' + entry.status.toLowerCase();
+                }
+
+                icon = 'images/alert-128-orange.png';
+                interaction = false;
+                break;
+
+            case 'CRITICAL':
+                if (entry.old_status === 'WARNING') {
+                    status = 'escalated to ' + entry.status.toLowerCase();
+                }
+
+                icon = 'images/alert-128-red.png';
+                interaction = true;
+                break;
+
+            default:
+                console.log('invalid alarm status ' + entry.status);
+                return;
+        }
+
+        // filter recipients
+        if (show) {
+            show = NETDATA.alarms.recipientMatches(entry.recipient, NETDATA.alarms.recipients);
+        }
+
+        /*
+        // cleanup old notifications with the same alarm_id as this one
+        // it does not seem to work on any web browser - so notifications cannot be removed
+
+        let len = NETDATA.alarms.notifications_shown.length;
+        while (len--) {
+            let n = NETDATA.alarms.notifications_shown[len];
+            if (n.data.alarm_id === entry.alarm_id) {
+                console.log('removing old alarm ' + n.data.unique_id);
+
+                // close the notification
+                n.close.bind(n);
+
+                // remove it from the array
+                NETDATA.alarms.notifications_shown.splice(len, 1);
+                len = NETDATA.alarms.notifications_shown.length;
+            }
+        }
+        */
+
+        if (show) {
+            if (typeof NETDATA.alarms.notificationCallback === 'function') {
+                show = NETDATA.alarms.notificationCallback(entry);
+            }
+
+            if (show) {
+                setTimeout(function () {
+                    // show this notification
+                    // console.log('new notification: ' + title);
+                    let n = new Notification(title, {
+                        body: entry.hostname + ' - ' + entry.chart + ' (' + entry.family + ') - ' + status + ': ' + entry.info,
+                        tag: tag,
+                        requireInteraction: interaction,
+                        icon: NETDATA.serverStatic + icon,
+                        data: data
+                    });
+
+                    n.onclick = function (event) {
+                        event.preventDefault();
+                        NETDATA.alarms.onclick(event.target.data);
+                    };
+
+                    // console.log(n);
+                    // NETDATA.alarms.notifications_shown.push(n);
+                    // console.log(entry);
+                }, NETDATA.alarms.ms_penalty);
+
+                NETDATA.alarms.ms_penalty += NETDATA.alarms.ms_between_notifications;
+            }
+        }
+    },
+
+    scrollToChart: function (chart_id) {
+        if (typeof chart_id === 'string') {
+            let offset = $('#' + NETDATA.alarms.chart_div_id_prefix + NETDATA.name2id(chart_id)).offset();
+            if (typeof offset !== 'undefined') {
+                $('html, body').animate({scrollTop: offset.top + NETDATA.alarms.chart_div_offset}, NETDATA.alarms.chart_div_animation_duration);
+                return true;
+            }
+        }
+        return false;
+    },
+
+    scrollToAlarm: function (alarm) {
+        if (typeof alarm === 'object') {
+            let ret = NETDATA.alarms.scrollToChart(alarm.chart);
+
+            if (ret && NETDATA.options.page_is_visible === false) {
+                window.focus();
+            }
+            //    alert('netdata dashboard will now scroll to chart: ' + alarm.chart + '\n\nThis alarm opened to bring the browser window in front of the screen. Click on the dashboard to prevent it from appearing again.');
+        }
+
+    },
+
+    notifyAll: function () {
+        // console.log('FETCHING ALARM LOG');
+        NETDATA.alarms.get_log(NETDATA.alarms.last_notification_id, function (data) {
+            // console.log('ALARM LOG FETCHED');
+
+            if (data === null || typeof data !== 'object') {
+                console.log('invalid alarms log response');
+                return;
+            }
+
+            if (data.length === 0) {
+                console.log('received empty alarm log');
+                return;
+            }
+
+            // console.log('received alarm log of ' + data.length + ' entries, from ' + data[data.length - 1].unique_id.toString() + ' to ' + data[0].unique_id.toString());
+
+            data.sort(function (a, b) {
+                if (a.unique_id > b.unique_id) {
+                    return -1;
+                }
+                if (a.unique_id < b.unique_id) {
+                    return 1;
+                }
+                return 0;
+            });
+
+            NETDATA.alarms.ms_penalty = 0;
+
+            let len = data.length;
+            while (len--) {
+                if (data[len].unique_id > NETDATA.alarms.last_notification_id) {
+                    NETDATA.alarms.notify(data[len]);
+                }
+                //else
+                //    console.log('ignoring alarm (older) with id ' + data[len].unique_id.toString());
+            }
+
+            NETDATA.alarms.last_notification_id = data[0].unique_id;
+
+            if (typeof netdataAlarmsRemember === 'undefined' || netdataAlarmsRemember) {
+                NETDATA.localStorageSet('last_notification_id', NETDATA.alarms.last_notification_id, null);
+            }
+            // console.log('last notification id = ' + NETDATA.alarms.last_notification_id);
+        })
+    },
+
+    check_notifications: function () {
+        // returns true if we should fire 1+ notifications
+
+        if (NETDATA.alarms.notifications !== true) {
+            // console.log('web notifications are not available');
+            return false;
+        }
+
+        if (Notification.permission !== 'granted') {
+            // console.log('web notifications are not granted');
+            return false;
+        }
+
+        if (typeof NETDATA.alarms.current !== 'undefined' && typeof NETDATA.alarms.current.alarms === 'object') {
+            // console.log('can do alarms: old id = ' + NETDATA.alarms.last_notification_id + ' new id = ' + NETDATA.alarms.current.latest_alarm_log_unique_id);
+
+            if (NETDATA.alarms.current.latest_alarm_log_unique_id > NETDATA.alarms.last_notification_id) {
+                // console.log('new alarms detected');
+                return true;
+            }
+            //else console.log('no new alarms');
+        }
+        // else console.log('cannot process alarms');
+
+        return false;
+    },
+
+    get: function (what, callback) {
+        $.ajax({
+            url: NETDATA.alarms.server + '/api/v1/alarms?' + what.toString(),
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkOptional('/api/v1/alarms', data /*, '.*\.(calc|calc_parsed|warn|warn_parsed|crit|crit_parsed)$' */);
+
+                if (NETDATA.alarms.first_notification_id === 0 && typeof data.latest_alarm_log_unique_id === 'number') {
+                    NETDATA.alarms.first_notification_id = data.latest_alarm_log_unique_id;
+                }
+
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
+            })
+            .fail(function () {
+                NETDATA.error(415, NETDATA.alarms.server);
+
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    },
+
+    update_forever: function () {
+        if (netdataShowAlarms !== true || netdataSnapshotData !== null) {
+            return;
+        }
+
+        NETDATA.alarms.get('active', function (data) {
+            if (data !== null) {
+                NETDATA.alarms.current = data;
+
+                if (NETDATA.alarms.check_notifications()) {
+                    NETDATA.alarms.notifyAll();
+                }
+
+                if (typeof NETDATA.alarms.callback === 'function') {
+                    NETDATA.alarms.callback(data);
+                }
+
+                // Health monitoring is disabled on this netdata
+                if (data.status === false) {
+                    return;
+                }
+            }
+
+            setTimeout(NETDATA.alarms.update_forever, NETDATA.alarms.update_every);
+        });
+    },
+
+    get_log: function (last_id, callback) {
+        // console.log('fetching all log after ' + last_id.toString());
+        $.ajax({
+            url: NETDATA.alarms.server + '/api/v1/alarm_log?after=' + last_id.toString(),
+            async: true,
+            cache: false,
+            headers: {
+                'Cache-Control': 'no-cache, no-store',
+                'Pragma': 'no-cache'
+            },
+            xhrFields: {withCredentials: true} // required for the cookie
+        })
+            .done(function (data) {
+                data = NETDATA.xss.checkOptional('/api/v1/alarm_log', data);
+
+                if (typeof callback === 'function') {
+                    return callback(data);
+                }
+            })
+            .fail(function () {
+                NETDATA.error(416, NETDATA.alarms.server);
+
+                if (typeof callback === 'function') {
+                    return callback(null);
+                }
+            });
+    },
+
+    init: function () {
+        NETDATA.alarms.server = NETDATA.fixHost(NETDATA.serverDefault);
+
+        if (typeof netdataAlarmsRemember === 'undefined' || netdataAlarmsRemember) {
+            NETDATA.alarms.last_notification_id =
+                NETDATA.localStorageGet('last_notification_id', NETDATA.alarms.last_notification_id, null);
+        }
+
+        if (NETDATA.alarms.onclick === null) {
+            NETDATA.alarms.onclick = NETDATA.alarms.scrollToAlarm;
+        }
+
+        if (typeof netdataAlarmsRecipients !== 'undefined' && Array.isArray(netdataAlarmsRecipients)) {
+            NETDATA.alarms.recipients = netdataAlarmsRecipients;
+        }
+
+        if (netdataShowAlarms) {
+            NETDATA.alarms.update_forever();
+
+            if ('Notification' in window) {
+                // console.log('notifications available');
+                NETDATA.alarms.notifications = true;
+
+                if (Notification.permission === 'default') {
+                    Notification.requestPermission();
+                }
+            }
+        }
+    }
+};

web/gui/src/dashboard.js/boot.js

@@ -0,0 +1,142 @@
+
+// Load required JS libraries and CSS
+
+NETDATA.requiredJs = [
+    {
+        url: NETDATA.serverStatic + 'lib/bootstrap-3.3.7.min.js',
+        async: false,
+        isAlreadyLoaded: function () {
+            // check if bootstrap is loaded
+            if (typeof $().emulateTransitionEnd === 'function') {
+                return true;
+            } else {
+                return typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap;
+            }
+        }
+    },
+    {
+        url: NETDATA.serverStatic + 'lib/fontawesome-all-5.0.1.min.js',
+        async: true,
+        isAlreadyLoaded: function () {
+            return typeof netdataNoFontAwesome !== 'undefined' && netdataNoFontAwesome;
+        }
+    },
+    {
+        url: NETDATA.serverStatic + 'lib/perfect-scrollbar-0.6.15.min.js',
+        isAlreadyLoaded: function () {
+            return false;
+        }
+    }
+];
+
+NETDATA.requiredCSS = [
+    {
+        url: NETDATA.themes.current.bootstrap_css,
+        isAlreadyLoaded: function () {
+            return typeof netdataNoBootstrap !== 'undefined' && netdataNoBootstrap;
+        }
+    },
+    {
+        url: NETDATA.themes.current.dashboard_css,
+        isAlreadyLoaded: function () {
+            return false;
+        }
+    }
+];
+
+NETDATA.loadedRequiredJs = 0;
+NETDATA.loadRequiredJs = function (index, callback) {
+    if (index >= NETDATA.requiredJs.length) {
+        if (typeof callback === 'function') {
+            return callback();
+        }
+        return;
+    }
+
+    if (NETDATA.requiredJs[index].isAlreadyLoaded()) {
+        NETDATA.loadedRequiredJs++;
+        NETDATA.loadRequiredJs(++index, callback);
+        return;
+    }
+
+    if (NETDATA.options.debug.main_loop) {
+        console.log('loading ' + NETDATA.requiredJs[index].url);
+    }
+
+    let async = true;
+    if (typeof NETDATA.requiredJs[index].async !== 'undefined' && NETDATA.requiredJs[index].async === false) {
+        async = false;
+    }
+
+    $.ajax({
+        url: NETDATA.requiredJs[index].url,
+        cache: true,
+        dataType: "script",
+        xhrFields: {withCredentials: true} // required for the cookie
+    })
+        .done(function () {
+            if (NETDATA.options.debug.main_loop) {
+                console.log('loaded ' + NETDATA.requiredJs[index].url);
+            }
+        })
+        .fail(function () {
+            alert('Cannot load required JS library: ' + NETDATA.requiredJs[index].url);
+        })
+        .always(function () {
+            NETDATA.loadedRequiredJs++;
+
+            // if (async === false)
+            if (!async) {
+                NETDATA.loadRequiredJs(++index, callback);
+            }
+        });
+
+    // if (async === true)
+    if (async) {
+        NETDATA.loadRequiredJs(++index, callback);
+    }
+};
+
+NETDATA.loadRequiredCSS = function (index) {
+    if (index >= NETDATA.requiredCSS.length) {
+        return;
+    }
+
+    if (NETDATA.requiredCSS[index].isAlreadyLoaded()) {
+        NETDATA.loadRequiredCSS(++index);
+        return;
+    }
+
+    if (NETDATA.options.debug.main_loop) {
+        console.log('loading ' + NETDATA.requiredCSS[index].url);
+    }
+
+    NETDATA._loadCSS(NETDATA.requiredCSS[index].url);
+    NETDATA.loadRequiredCSS(++index);
+};
+
+// Boot it!
+
+if (typeof netdataPrepCallback === 'function') {
+    netdataPrepCallback();
+}
+
+NETDATA.errorReset();
+NETDATA.loadRequiredCSS(0);
+
+NETDATA._loadjQuery(function () {
+    NETDATA.loadRequiredJs(0, function () {
+        if (typeof $().emulateTransitionEnd !== 'function') {
+            // bootstrap is not available
+            NETDATA.options.current.show_help = false;
+        }
+
+        if (typeof netdataDontStart === 'undefined' || !netdataDontStart) {
+            if (NETDATA.options.debug.main_loop) {
+                console.log('starting chart refresh thread');
+            }
+
+            NETDATA.start();
+        }
+    });
+});