Saturday, February 04, 2012

Visual GC Error: Not Supported for this JVM

The Visual GC plugin for Visual VM graphically displays garbage collection, class loader, and HotSpot compiler performance data.

If you install this plugin and, like me, get the error "Not Supported for this JVM", when you try to start Visual GC, try the following steps:

  1. Start jstatd on the remote host. You need to specify a policy file, otherwise you will get an AccessControlException: access denied exception. Create a policy file e.g. /tmp/tools.policy containing:
    grant codebase "file:${java.home}/../lib/tools.jar" {
    Then start jstatd using the command below:
  2. Start Visual VM. Add a Remote Host and then add a "jstatd connection" to it. Your JVM should appear in the list. You can then click on it and look at the "Visual GC" tab for garbage collection information.