What is the "VM Periodic Task Thread"?

Question

I can see this thread in my thread dump:

"VM Periodic Task Thread" prio=10 tid=0x00007fc23000e800 nid=0x49e6 waiting on condition

What is it?

Answer 1

Having a look at the latest OpenJDK source, this is C++ level thread which performs a number of tasks on systems where there is not a native timer interrupt.

It appears to be mostly used for sampling/profiling what the JVM is doing.