Charting Time-Series Data

The Charts Search page in the Cloudera Manager Admin Console enables you to search for a time series, plot the time-series data, group (facet) the individual time series if your search produced multiple time series, and save the results as a user-defined view.

You use the The tsquery Language to retrieve time-series data from the Cloudera Manager time-series data store.

To create a custom view with time-series charts of your own choosing, follow the procedures in Creating a Custom View.

To access the charts search page, in the Cloudera Manager Admin Console, select Charts > Search.

The following sections have more details on the terminology used, editing time-series plots, and saving and managing chart views:

Terminology

Entity
A Cloudera Manager component that has metrics associated with it, such as a service, role, role type, or host.
Metric
A property that can be measured to quantify the state of an entity or activity, such as the number of open file descriptors or CPU utilization percentage.
Time series
A list of (time, value) pairs that is associated with some (entity, metric) pair. For example, (datanode-1, fd_open), (hostname, cpu_percent). In more complex cases, the time series can represent operations on other time series. For example, (datanode-1 , cpu_user + cpu_system).
Facet
A display grouping of the dataset, shown in separate charts. By default, when a query returns multiple time series, they are displayed in individual charts. Facets allow you to display the time series in separate charts, in a single chart, or grouped by various attributes of the set of time series.

Searching for Time-Series Data

You can search for a time series in the Cloudera Manager Admin Console in two ways: by selecting from a list of metrics or by constructing a tsquery statement in the Search text box.

Search Method Procedure
List of Metrics
  1. Click the List of Metrics link to display a list of metrics organized in categories.
  2. Type a name or description of the metric in the Filter by Metric... text box. As you type, only the list of categories containing metrics that match the letters will display.
  3. Click a category to display the metrics related to that category. Note that some metrics will appear in multiple categories as they may apply to more than one entity or activity (for example, the Alerts metric applies to a large number of categories).
  4. Click the metric that you want to chart. The corresponding tsquery statement will appear in the text box and the chart(s) that display that time series will display.
tsquery Statement
  1. Press Spacebar in the Search text box. tsquery statement components display in a drop-down list. These suggestions are part of typeahead, which helps build valid queries. Scroll to the desired component and click Enter. Continue choosing query components by pressing Spacebar and Enter until the tsquery statement is complete.
  2. Click the Search button.

For example, the query SELECT jvm_heap_used_mb where clusterId = 1 could return a set of charts like the following:



Editing Time-Series Plots

The time-series data retrieved by the tsquery are displayed on different charts. By default, each time series is displayed on its own chart, using a Line style chart, a default size, and a default minimum and maximum for the Y-axis.

To change the chart-type, click one of the possible chart-types on the left: Line, Stack Area, Bar, and Scatter.

Grouping (Faceting) Time Series

Every time series returned by the query has a set of attributes associated with it. In this case, each time series will have a hostname, role type, metric, and entity name attribute. The charting function can group (or facet) the time series into different numbers of charts by considering these attributes. By default, all time series are plotted on their own chart (with facets set to All Separate) as shown in Searching for Time-Series Data. If serviceName is selected for the Faceting option for the query, the time series is grouped on four charts, one chart each for each service name. The charts for service types with multiple roles will show multiple lines (for example, HBase, HDFS) while services that have only one role (for example, ZooKeeper) will show just a single line.

Changing Dimensions and Axes

You can change the size of your charts by moving the DIMENSION slider. It moves in 50-pixel increments. If you have multiple charts, depending on the dimensions you specify and the size of your browser window, your charts may appear in rows of multiple charts.

The following chart shows the same query as the previous chart, but with All Combined selected (which shows all time series in a single chart) and with the DIMENSION slider used to expand the chart.

You can change the Y-axis range using the Y RANGE minimum and maximum fields.

The X-axis is based on clock time, and by default shows the last half hour of data. You can change the time range for your plot using the time range sets shown at the upper right of the window (right below the Time Range Selector) or by expanding or shrinking the Time Range Selector.

Saving a View

You can save the charts and their configurations (chart-type, dimension, and y-axis minimum and maximum) as a view. To save the plots as a new view, click the Save as View button, enter a view name, and then click Create. The new view will appear on the menu under the top-level Charts Library tab so that you can select it later. See Creating a Custom View for more information.

Managing Chart Views

The All Charts View option under the top level Charts menu lets you import, export, and remove views.

Export exports the specifications for the charts in the view as a JSON file.

Import reads an exported JSON file and recreates the charts.

Remove deletes the view.