Cucumber Selenium Tests taking longer duration in multi-threaded mode on latest chrome versions and on AL2 Linux machine

[Venkatesh P]

Hi Everyone,

Our automation scripts are developed using Cucumber and Selenium. These scripts are run in Jenkins pipeline in multi-threaded mode using 4 threads. Then the failed scripts are rerun (as UI tests can be flaky) within the same pipeline but using single thread.

Few months back, we started upgrading Chrome to 108 and suddenly we noticed all our pipelines were taking longer duration. In the multi-threaded run, we noticed some scripts failing (due to CSS not displayed, not visible (or not loading) until some wait time) and also passed scripts taking longer duration compared to Chrome 80 run. However, the failed scripts are running fine in the rerun which is single threaded. So, we concluded that the issue is happening only in multi-threaded run. We also tried running using Chrome 107, 109, 111, 113 and 114), but we see the same issue.

We ran our test suite on Windows and Mac in multi-threaded mode and observed that the tests are running fine without taking longer duration. It is almost same as the Chrome 80 run on AL2 Linux. Then we concluded that this issue is happening on AL2 Linux and on latest chrome versions (started somewhere from > 80 and < 108 version) in multi-threaded mode only.
Not exactly sure if the latest chrome has performance issues on AL2 linux OR latest linux chrome driver has performance issues OR issues with the combination of Selenium, latest chrome driver and latest chrome on AL2 Linux in Multi-Threaded mode.

Did anyone observe this or similar issue and able to resolve? Can someone please suggest how to resolve OR overcome this issue? (We have very huge number of test cases and so many pipelines to run the scripts. So, running tests in single thread is not an effective solution for us.)