Similar to bug 22641, Jenkins no longer cleaning up child processes when a job is stopped.
To reproduce : Start any job with a surefire execution, once the tests start running, stop the job through the jenkins interface. The surefire process continues to run.
Just like bug 22641, this behavior started in 1.553, was resolved in 1.565.2, then started again in 1.587.
Rating this as critical because processes build up eventually causing issues with running out of memory or hitting the nproc limit.