How to stop stuck jmeter executed in GUI mode

Question

When I run Jmeter java swing application in GUI mode and it got stuck (GUI not responding),

How can I stop/shutodown it without kill the process?

Answer 1

When UI is stuck, it's too late to do anything. You can try to cause a full GC, but your chances to even improve the situation are low: it won't help if OOM already happened, or if full GC was already triggered by JVM, but did not help. And even if it helps, likely the improvement will be temporary (it may be enough just to stop test properly, rather than abruptly). And continuing test after that state is not a good idea, since the results will be unreliable.

A better idea is to prevent JMeter from getting into that state:

• Follow Best Practices (specifically Reducing resource requirements paragraph)
• Make sure you provided Java running JMeter with adequate memory settings. See this discussion for more details on memory parameters.
• Make sure machine itself has enough memory.
• If it's a VM, make sure you are not over-committing physical memory on a host.

Answer 2

I am not aware of any way to "unfreeze" a hung test, most probably you have ruined it and there are no recovery options. You could try waiting for the test to finish if your JVM is not completely dead, but depending on your configuration it may take hours or even days (we need to see your thread dump in order to be able to suggest anything)

In general JMeter GUI is designed for tests development and debugging only as it evidenced by this warning which is displayed on every launch of JMeter:

So going forward please run JMeter in command-line non-GUI mode when it comes to executing a load test. Also it worth sticking to recommendations from the 9 Easy Solutions for a JMeter Load Test “Out of Memory” Failure, this way you will be able to tune JMeter for maximum performance.