This document describes how to configure a temporary chart that displays the time-series data collected by your project. Metrics Explorer can display only numeric time-series data. Show
Select the data to displayThere are different ways that you can specify the time series to display when you use Metrics Explorer:
Menu-driven InterfacesTo use menus to specify time series to display, do the following:
Direct filter modeUse direct filter mode when you are interested in charting any of the following:
You must also use direct filter mode when you want to filter time series based on a user label for which you don't yet have data. Direct filter mode lets you enter an expression that Monitoring uses to identify the time series to be monitored. The expressions that you enter in direct filter mode are sometimes referred to as metric filters or Monitoring filters. For example, the following expression results in
a chart displaying a count of processes whose name includes
You can also use Monitoring filters to identify time series by their resource and metric type. The following expression results in a chart displaying the count of log entries for all Google Cloud virtual machine instances in the
To enter a Monitoring filter, do the following:
To return to the menu-driven interface, click Standard mode. Filter charted dataYou can reduce the amount of data to be charted by specifying filter criteria, applying aggregation, or by using outlier mode. Filters ensure that only time series that meet some set of criteria are used. When you apply filters, you might reduce the number of lines on the chart, which can improve the performance of the chart. The remainder of this section applies to configuring a chart when using a menu-driven interface. This section isn't applicable to MQL and Monitoring configurations, which include filter statements. When you supply multiple filtering criteria, the corresponding chart shows only the time series that meet all criteria, a logical To add a filter when you use the Configuration tab, click Add filter and then specify the filter label, the comparison, and the value or range of values:
You can specify multiple filter criteria, and you can use the same label multiple times. These capabilities let you specify a filter for a range of values. All filter criteria must be met; they constitute a logical Choose how to display charted dataThe section covers how to display the selected data by setting the aggregation fields. Aggregation consists of alignment of data points within a time series, and combining different time series together. For a detailed explanation of aggregation, see Filtering and aggregation: manipulating time series.
Group time seriesYou can reduce the amount of data returned for a metric by combining different time series. To combine multiple time series, you typically specify a grouping and a function. Grouping is done by label values. The function defines how all time-series data within a group are combined into a new time series. To add a grouping, click the text in the Group by text box, and then make a selection from the menu. The menu is constructed dynamically based on the time-series data for the resource and metric you selected. Grouping and filtering use the same set of labels. When you add the first label, the following occurs:
If you group by multiple labels, then the aggregator combines those times series that have the same value for the specified labels. If you don't specify a grouping option and do specify an aggregator, then that function is applied to all selected time series and results in a single time series. For example, if the Group by field is set to You can group by multiple labels. When you have multiple grouping options, the aggregator is applied to the set of time series that have the same values for the selected labels. The resulting chart displays one time series for each combination of label values. The order in which you specify the labels doesn't matter. For
example, the following screenshot illustrates grouping by As illustrated, if you group by both the labels, you get one time series for each pair of values. The fact that you get a time series for each combination of labels means that this technique can easily create more data than you can usefully put on a single chart. When you specify grouping or if you select an aggregator, the charted time series only contains required labels, such as the project identifier, and the labels specified by the grouping. Remove group-by conditionsTo remove a group-by condition, you must:
Align time seriesAlignment is the process of converting the time series data received by Monitoring into a new time series which has data points at fixed intervals. The process of alignment consists of collecting all data points received in a fixed length of time, applying a function to combine those data points, and assigning a timestamp to the result. That function might compute the average of all samples or it might extract the maximum of all samples. The Alignment period specifies the minimum time interval to be used when aligning time series data. When there are too many data points to chart in the selected display period, then the alignment period is automatically increased so that every data point is represented. The default setting for this field is one minute. The Aligner field specifies the function used to combine all the data points in an alignment period. Most of the aligners perform common mathematical functions. For example, if you select min, then the aligned data point is the minimum of all data points within the alignment period. For example, consider a metric with a sampling period of one minute. If a chart is configured to display 1 hour of data, then the chart can display all 60 data points. If the alignment period is set to While most of the aligners perform common mathematical functions, some perform more complicated actions:
For more information on the available aligners, see
To view or modify the alignment function, click Show advanced options. The following screenshot illustrates the CPU utilization of the Compute Engine VM instances in a particular Google Cloud project. In this image, the alignment fields are at the default values: the alignment function is set to For comparison, the following screenshot illustrates the effect of changing the period from By increasing the period, the resulting chart has fewer points, decreasing from 60 points per time series to 10 points per time series. Each point on the chart is computed by averaging the time series points in an alignment period. By increasing the alignment period, more points are averaged together, which has a smoothing effect on the plotted data. Secondary aggregationWhen you have multiple time series that already represent aggregations, you can reduce all the time series on the chart to a single time series by choosing a Secondary Aggregator. For example, if you group data by zone, your chart shows one time series for each zone. To create a chart with a single time series, use the secondary aggregation fields. To view or modify the secondary aggregation settings, click Show advanced options. The following screenshot shows several time series that result from grouping a filtered set of data. The use of grouping requires aggregation; each group of lines is aggregated into one. The following screenshot shows time series grouped by zone: The following screenshot shows the result of using secondary aggregation to find the mean value across the grouped time series: Legend TemplateThe Legend Template field lets you customize a description for the time series on your chart. These descriptions appear on the tooltip for the chart and on the chart legend in the Name column. By default, the descriptions in the legend are created for you from the values of different labels in your time series. Because the system selects the labels, the results might not be helpful to you. To build a template for descriptions, use this field. To access the legend template for a chart, in the Google Cloud console, select the Advanced tab in the chart's configuration pane. The legend template is listed under the heading Additional options. You can enter plain text and templates in the Legend Template field. When you add a template, you add an expression that is evaluated when the legend is displayed. To add a template, do the following:
For example, the following screenshot shows a legend template that contains plain text and the expression In the chart legend, the values generated from the template appear in a column with the header Name and in the tooltip: You can configure the legend template to include multiple text strings and templates; however, the display space available on the tooltip is limited. What's next
What is the process of displaying only a portion of the data based on matching a specific value to show only the data that meets the criteria that you specify is called?The process of displaying only a portion of the data based on matching a specific value to show only the data that meets the criteria that you specify is called: Filtering.
What is the process of arranging data in a specific order based on the value in each field?Data sorting is any process that involves arranging the data into some meaningful order to make it easier to understand, analyze or visualize.
What is the term for the values that a function used to perform operations or calculations?Functions are predefined formulas that perform calculations by using specific values, called arguments, in a particular order, or structure.
What provides a visual cue about the value of a cell relative to other cells?A cell format consisting of a shaded bar that provides a visual cue to the reader about the value of a cell relative to other cells; the length of the bar represents the value in the cell—a longer bar represents a higher value and a shorter bar represents a lower value.
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