Identify performance regressions by comparing load test runs
In this article, you'll learn how to identify performance regressions by visually comparing multiple load test runs in the Azure Load Testing Preview dashboard.
A test run contains client-side and server-side metrics. The test engine reports client-side metrics, such as the number of virtual users. The server-side metrics provide application- and resource-specific information.
By overlaying multiple metrics charts, you can more easily pinpoint performance changes and identify which application component is causing problems.
There are two entry points for comparing load test runs in the Azure portal:
- Starting from the test runs page, select multiple results to compare.
- Starting from a specific test run, select other results to compare the runs with.
Important
Azure Load Testing is currently in preview. For legal terms that apply to Azure features that are in beta, in preview, or otherwise not yet released into general availability, see the Supplemental Terms of Use for Microsoft Azure Previews.
Prerequisites
An Azure account with an active subscription. If you don't have an Azure subscription, create a free account before you begin.
An Azure Load Testing resource with a test plan that has multiple test runs. To create a Load Testing resource, see Create and run a load test.
Note
If you want to compare a test run, it needs to be in a Done, Stopped, or Failed state.
Compare test runs from the test runs page
In this section, you'll compare multiple results by selecting runs from the test runs page.
Sign in to the Azure portal by using the credentials for your Azure subscription.
Go to your Azure Load Testing resource and then, on the left pane, select Tests.
You can also use the filters to find your load test.
In the list of tests, select the test whose runs you want to compare.
Select two or more test runs, and then select Compare.
Note
You can choose a maximum of five test runs to compare.
The selected test runs are presented in the dashboard. Each run is shown as an overlay in the different charts.
You can use filters to customize the graphs. There are separate filters for the client and server metrics.
Tip
The time filter is based on the relative duration of the tests. A value of zero indicates the beginning of the test, and the maximum value marks the duration of the longest test run. For client-side metrics, test runs show only data for the duration of the test.
Compare test runs from the run details page
In this section, you'll use the test run details page and add other test runs to compare.
Go to the test run details page, and then select Compare.
On the Compare page, select two or more test runs that you want to compare.
Note
You can choose a maximum of five test runs to compare.
Select Compare.
The selected test runs are presented in the dashboard. Each run is shown as an overlay in the different charts.
You can use filters to customize the graphs. There are separate filters for the client and server metrics.
Next steps
For information about high-scale load tests, see Set up a high-scale load test.
To learn about performance test automation, see Configure automated performance testing.