Found an interesting video on how to use Visual VM that comes with JDK 6 update 7 to see what’s happening in Glassfish. Looks like an interesting tool to find out whether your app servers are leaking memory.
Java VisualVM User Guide:
http://java.sun.com/javase/6/docs/technotes/guides/visualvm/index.html
VisualVM project page:
https://visualvm.dev.java.net/gettingstarted.html
