what is the role of “vm thread” in JDK 1.6 [duplic

问题:

This question already has an answer here:

• What does java “VM thread” do? 3 answers

We are seeing lot of activity of this thread in our customer's system and hence would like to know what might be happening.

any links, info, tutorials ?

P.S : this is happening on Solaris 10 with JDK 1.6.0_23.

回答1:

this thread will give you some step to proceed. If possible i will provide more. http://mail.openjdk.java.net/pipermail/hotspot-dev/2009-February/001249.html

This some more details i can share about VM thread

If the “Current thread” is the VMThread then you need to look for the “VM_Operation” line in the THREAD section. The VM thread is a special thread in the HotSpot VM. It performs special tasks in the VM such as garbage collection. If the VM_Operation suggests that the operation is a garbage collection then it is possible that you have encountered as issue such as heap corruption. The crash might also be a garbage collector issue, but it could equally be something else (such as a compiler or runtime bug) that leaves object references in the heap in an inconsistent or incorrect state. In this case it is best to collect as much information as possible about the environment and try out possible workarounds. If the issue is GC related then you may be able to temporarily workaround the issue by changing the GC configuration. This is discussed in the following section.

also check this link for more information http://www.oracle.com/technetwork/java/jdk50-ts-guide-149808.pdf