Learn how to use Netdata's powerful charts to troubleshoot with real-time, per-second metric data.
Netdata excels in collecting, storing, and organizing metrics in out-of-the-box dashboards. To make sense of all the metrics, Netdata offers an enhanced version of charts that update every second.
These charts provide a lot of useful information, so that you can:
These charts are available on Netdata Cloud's Overview tab, Single Node tab and on your Custom Dashboards.
Some of the features listed below are also available on the simpler charts that are available on each agent's user interface.
Have a look at the can see the overall look and feel of the charts for both with a composite chart from the Overview tab and a simple chart from the Single Node tab:
With a quick glance you have immediate information available at your disposal:
Your charts are controlled using the available Time controls. Besides these, when interacting with the chart you can also activate these controls by:
Interaction | Keyboard/mouse | Touchpad/touchscreen | Time control |
---|---|---|---|
Pause a chart | hover |
n/a |
Temporarily Pause |
Stop a chart | click |
tap |
Pause |
Reset a chart | double click |
n/a |
Play |
Note: These interactions are available when the default "Pan" action is used. Other actions are accessible via the Exploration action bar.
When you start interacting with a chart, you'll notice valuable information on the top bar. You will see information from the chart title to a chart action bar.
The elements that you can find on this top bar are:
Each composite chart has a definition bar to provide information about the following:
Click on the dimension dropdown to change how a composite chart groups metrics.
The default option is by dimension, so that each line/area in the visualization is the aggregation of a single dimension. This provides a per dimension view of the data from all the nodes in the War Room, taking into account filtering criteria if defined.
A composite chart grouped by node visualizes a single metric across contributing nodes. If the composite chart has five contributing nodes, there will be five lines/areas. This is typically an absolute value of the sum of the dimensions over each node but there are some opinionated-but-valuable exceptions where a specific dimension is selected. Grouping by nodes allows you to quickly understand which nodes in your infrastructure are experiencing anomalous behavior.
A composite chart grouped by instance visualizes each instance of one software or hardware on a node and displays
these as a separate dimension. By grouping the
disk.io
chart by instance, you can visualize the activity of each disk on each node that contributes to the
composite
chart.
Another very pertinent example is composite charts over contexts related to cgroups (VMs and containers). You have the means to change the default group by or apply filtering to get a better view into what data your are trying to analyze. For example, if you change the group by to instance you get a view with the data of all the instances (cgroups) that contribute to that chart. Then you can use further filtering tools to focus the data that is important to you and even save the result to your own dashboards.
Each chart uses an opinionated-but-valuable default aggregate function over the data sources. For example,
the system.cpu
chart shows the
average for each dimension from every contributing chart, while the net.net
chart shows the sum for each dimension
from every contributing chart, which can also come from multiple networking interfaces.
The following aggregate functions are available for each selected dimension:
out
dimension—-2.1
, -5.5
, -10.2
, -15
, -0.1
—the composite chart displays a
value of −6.58
.-32.9
.Select which dimensions to display on the composite chart. You can choose All dimensions, a single dimension, or any number of dimensions available on that context.
Click on X Instances to display a dropdown of instances and nodes contributing to that composite chart. Each line in the dropdown displays an instance name and the associated node's hostname.
Click on X Nodes to display a dropdown of nodes contributing to that composite chart. Each line displays a hostname to help you identify which nodes contribute to a chart. You can also use this component to filter nodes directly on the chart.
If one or more nodes can't contribute to a given chart, the definition bar shows a warning symbol plus the number of
affected nodes, then lists them in the dropdown along with the associated error. Nodes might return errors because of
networking issues, a stopped netdata
service, or because that node does not have any metrics for that context.
When the granularity of the data collected is higher than the plotted points on the chart an aggregation function over time is applied. By default the aggregation applied is average but the user can choose different options from the following:
*
*
**
Info
*
For Trimmed Median and Mean you can choose the percentage of data tha you want to focus on: 1%, 2%, 3%, 5%, 10%, 15%, 20% and 25%.**
For Percentile you can specify the percentile you want to focus on: 25th, 50th, 75th, 80th, 90th, 95th, 97th, 98th and 99th.
For more details on each, you can refer to our Agent's HTTP API details on Data Queries - Data Grouping.
Click on the 3-dot icon (⋮) on any chart, then Reset to Defaults, to reset the definition bar to its initial state.
Click on X Charts/X Nodes to display one of the two dropdowns that list the charts and nodes contributing to a given composite chart. For example, the nodes dropdown.
To jump to a single-node dashboard, click on the link icon
next to the
node you're interested in.
The single-node dashboard opens in a new tab. From there, you can continue to troubleshoot or run Metric Correlations for faster root cause analysis.
Click on the 3-dot icon (⋮) on any chart, then click on Add to Dashboard. Click the + button for any dashboard you'd like to add this composite chart to, or create a new dashboard an initiate it with your chosen chart by entering the name and clicking New Dashboard.
On this bar you have access to immediate actions over the chart, the available actions are:
When exploring the chart you will see a second action bar. This action bar is there to support you on this task. The available actions that you can see are:
Drag your mouse/finger to the right to pan backward through time, or drag to the left to pan forward in time. Think of it like pushing the current timeframe off the screen to see what came before or after.
Interaction | Keyboard | Mouse | Touchpad/touchscreen |
---|---|---|---|
Pan | n/a |
click + drag |
touch drag |
Selecting timeframes is useful when you see an interesting spike or change in a chart and want to investigate further by:
Interaction | Keyboard/mouse | Touchpad/touchscreen |
---|---|---|
Highlight a specific timeframe | Alt + mouse selection or ⌘ + mouse selection (macOS) |
n/a |
Zooming in helps you see metrics with maximum granularity, which is useful when you're trying to diagnose the root cause of an anomaly or outage. Zooming out lets you see metrics within the larger context, such as the last hour, day, or week, which is useful in understanding what "normal" looks like, or to identify long-term trends, like a slow creep in memory usage.
The actions above are normal vertical zoom actions. We also provide an horizontal zoom action that helps you focus on a specific Y-axis area to further investigate a spike or dive on your charts.
Interaction | Keyboard/mouse | Touchpad/touchscreen |
---|---|---|
Zoom in or out | Shift + mouse scrollwheel |
two-finger pinch Shift + two-finger scroll |
Zoom to a specific timeframe | Shift + mouse vertical selection |
n/a |
Horizontal Zoom a specific Y-axis area | Shift + mouse horizontal selection |
n/a |
You also have two direct action buttons on the exploration action bar for in-context Zoom in
and Zoom out
.
The bottom legend of the chart where you can see the dimensions of the chart can now be ordered by:
Hiding dimensions simplifies the chart and can help you better discover exactly which aspect of your system might be behaving strangely.
Interaction | Keyboard/mouse | Touchpad/touchscreen |
---|---|---|
Show one dimension and hide others | click |
tap |
Toggle (show/hide) one dimension | Shift + click |
n/a |
To resize the chart, click-and-drag the icon on the bottom-right corner of any chart. To restore the chart to its original height, double-click the same icon.