IntelliJ breakpoint and freezing of JVisualVM and JConsole

    Some time ago I had a situation where I had to use JVisualVM to check what happens within a test executed from IntelliJ and stopped on a breakpoint. JVisualVM had been hanging until I released the breakpoint. But why?

Diagnostic applications were freezed on these screens:

I checked my breakpoint within a test:

and everything became obvious. JVM exposes the interface for the diagnostic tools and the interface is handled by JVM internal threads which were suspended (Suspend -> All) according to the breakpoint definition. The solution was to select Suspend->Thread and mentioned diagnostic tools were able to connect to the JVM in which the test was being executed.