Monitor app performance over time

Looking to monitor for performance regressions in your app? Or just want to understand your app’s baseline performance for your users? In mabl, you can review performance metrics collected from test runs, including app load time and API response time, to monitor app performance over time.

This article suggests a workflow for reviewing your app’s performance from mabl test runs:

• Check for performance changes on the coverage page
• Review specific tests for more details
• Analyze performance at the step level
• Check on commonly used flows for slowdowns
• Run performance tests for further monitoring

By proactively monitoring key performance indicators in your mabl tests, you can identify and address slowdowns before they affect your customers.

Check for performance changes

A good place to start reviewing application performance is the coverage page: Coverage > Overview. To find the tests with the greatest performance slowdowns, check out the performance widget.

To review performance changes for all tests, check out the test status table. Here you can review performance for all test runs.

Reviewing performance across all tests on the coverage page

mabl measures performance with two metrics on the coverage page: app load time and API response time.

App load time

In browser tests, app load time is the sum of the speed index across every step of the test. It measures the performance of your app without the “mabl” parts of your tests like time spent on finds, waiting, asserting, and more. This metric represents the real experience of your application for your end-user.

Only Chrome and Edge runs from passing plans are included in the app load time metric.

API response time

In API tests, API response time measures the time between sending an API request and receiving a response. The coverage page measures cumulative API response time, or the total API response time across every request within this test. It excludes the time in between requests.

Only API tests from passing plan runs are included in the API response time metric.

Review specific tests for more details

From the coverage page, you can click on individual tests to review performance metrics for a specific test over time. Click on the Performance tab to review charts measuring app load time, API response time, and test run time. Test run time captures the entire test from startup to completion. Similar to the coverage page, the Performance tab only shows metrics from passing plan runs, and browser performance metrics only include Chrome and Edge runs.

Reviewing performance in specific tests

Check for regressions

A great use of the charts on the Performance tab is to monitor for performance regressions, especially if you’re running your tests on a regular cadence. Did the average app load time shoot up and to the right, and stay that way too? Check for deployments and major changes made around that time to your app, as it may indicate larger performance regressions that have been introduced.

By regularly reviewing these charts, you can monitor the baseline performance and investigate potential regressions before they escalate into bigger issues. To guide your analysis, ask yourself the following questions:

• Are the results consistent? Or do they vary a lot?
• Is it getting better or worse?

Reviewing API response time trends

Leverage filters

The charts and data in the Performance tab are filterable by environment using the environment dropdown selector and by application using the application filter in the top right corner of the app. When using either filter, the chart will only display runs that occurred on the app or environment that you’ve selected.

• Use the environment filter to isolate environments that may be experiencing degraded performance, as well as focus on stable environments that may have performance that better mirrors your production experience.
• Use the application filter to pinpoint, especially in larger workspaces, which app may be experiencing issues if your tests or flows are reused across multiple applications.

Analyze performance at the step level

From the Performance tab, you can click on dots in the charts to drill into specific test runs and analyze performance at the step level:

• Browser tests: for Chrome and Edge runs, the Performance tab for individual steps shows the speed index, which tracks page load performance over time.
• API tests: the Performance tab in step-level output shows the API response time, for the step over time.

Reviewing step-level output can be helpful for isolating performance issues. For example, the following speed index chart shows how an individual step contributed to a worsening performance trend but is also a performance anomaly that may be worth investigating further.

Speed index for a test step

Check on commonly used flows

mabl also collects performance metrics at the flow level, which can be especially insightful if you have flows that cover common user journeys. For example, you could monitor the performance of an important login flow to investigate potential regressions before they escalate into bigger issues.

Open a flow in the app and click on the Performance tab to review performance metrics for browser or API flows. Flow-level performance metrics are only captured for passing plan runs, and only on Chrome and Edge for browser flows.

Just like test performance metrics, flow performance metrics are filterable by environment and application in case you want to further isolate issues.

Run performance tests for further monitoring

Regularly reviewing performance in your browser and API tests is a good stepping stone to more robust performance validations. After establishing which browser and API tests validate key user journeys, you can add them as functional tests to a mabl performance test to validate your system under load.

Run it on a regular basis in pre-prod environments to ensure performance issues are caught before they impact customers. To learn more about performance tests, click here.