users@glassfish.java.net

Re: Problem with System.getProperty, not proper list format?! -- VisualVM

From: Russ Petruzzelli <Russ.Petruzzelli_at_Sun.COM>
Date: Thu, 11 Sep 2008 09:21:47 -0700

A great tool for monitoring (not just) memory (but lots more) is:
https://visualvm.dev.java.net/
I tried it yesterday for the first time and was really impressed. It
"just" installed. Easily. I have to complement the developers of
visualvm too. Great UI. (Think JConsole on steroids.) I installed the
"Thread Dump Analyzer" addon and located the source of a bottleneck I'd
been hunting for some time in just a few hours.

It has a special set of tabs customized for Glassfish too.
The bottleneck - by the way - was - all my request-processing threads
blocked:

    "httpSSLWorkerThread-8080-0" nid=71 state=BLOCKED
        - waiting on <0x7efd57e2> (a org.apache.log4j.Logger)
        - locked <0x7efd57e2> (a org.apache.log4j.Logger)

Might need a separate thread for that question, but would that class
fall under the Glassfish developement realm?

Russ


august2008 wrote:
> Hmm, you might need to monitor memory usage to see if that is the problem:
> hardly any memory available when the problem occurs again in contrary to
> enough when it is restarted. I know there are ways to monitor memory usage.
>
> *If* that is the problem you should check your application(s) to see which
> one is making the problem.
>
> I cannot help you more than these general directions. And actually Java
> should do automatic garbage collecting...
>
> Good luck!
>