Memory Accounting, JDKs [was: Re: [Techtalk] Java on Linux]

[Aaron Mulder]

On Thu, 10 Jan 2002, Nicole Zimmerman wrote:
> If you could find out what it is, it might be useful for what we are
> looking for.
> 
> It's times like this I wish I knew more about Java :o)

	One tool you might try is OptimizeIt.  It's commercial, but I
think there's an eval version available.  It can show you every object
instantiated in the VM, among other things, so you can poke around a
little and see if things aren't getting GC'd when you expect them to --
and what's holding the references that's keeping the alive.  But it is an
interactive GUI tool.  Still, you may be able to learn a lot just by
looking at the state of the various VMs during normal operation.
	If you really want to inspect the VM in batch mode, you should 
probably use the Java Platform Debugger Architecture 
(http://java.sun.com/products/jpda/).  That would let you connect to a 
running VM, and inspect it like a debugger would - objects, threads, 
memory, and all.  You can dump out whatever information you want, as 
often as you want.  But it's a little more hard-core.

Aaron