CI/CD Automated Rule Testing takes long time to complete

We have integrated the automated rule testing to our CI/CD pipeline. We are using a!startRuleTestsApplications to start the test. We notice on an average the entire test takes under 15 mins to complete, but on occasions the test takes a long time and we ultimately have to kill the build. 

Want to know how I can debug this. Unable to find anything in the tomcat logs. Is there any debug log I can enable to check where the test execution is stuck?