Favorite J2EE Profiler?

[NeoRye]

I'm looking for a good j2ee profiler to try and track down some memory issues my app is having. I'm new to the whole j2ee diagnostics, but the more I look into it the more I wonder how I've done without it for so long. I really like FusionReactor, but that doesn't go deep enough. Does anyone have a favorite? I'm looking at the new JProbe ( http://www.quest.com/jprobe/) and that looks pretty cool, but I'm having a hard time trying to configure it for my 10 jrun instances. Anyone have JProbe working and want to give me steps on setting it up?

I'd like something that can run against my live production server, since the issue I'm having is 500MB memory spikes with random requests and random times and then it does not release it at GC.

Thanks!

[Newsgroup_User]

Not a personal recommendation, I've not really used either, but I often
hear SeeFusion mentioned when FusionReactor is mentioned. Have you
checked that one out?

[NeoRye]

Those are both nice, but a bit higher level than what I'm looking for. I really need something to peak deaper into the jvm's memory and class usage.