We had strange near-daily outages of our internal busy jenkins for some weeks. To get to the root cause of the issue, we enabled remote debugging with -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=9010 -Dcom.sun.management.jmxremote.ssl=false -Djava.rmi.server.hostname=ci.suse.de -Dcom.sun.management.jmxremote.password.file=/var/lib/jenkins/jmxremote.password and attached visualvm to see what it was doing. This showed the number of threads and memory usage in a sawtooth pattern. Every …]