OT: Java gurus around ?

[Marc Ramirez]

On Tue, Sep 23, 2003 at 01:55:20PM -0700, Ulf Zimmermann wrote:
> Hello,
> 
> a bit off topic but as we got so much bright heads here .... :-)
> 
> The company I work for got a java application which uses Apache
> and Tomcat 4x as application server. Also used is Javagroups to
> provide session state between machines. So far this was run on
> Solaris Sparc hardware and we have no seen the issues we see now
> on Linux (baeh, I want to run FreeBSD /rude Oracle, require
> Oracle 9i libs because of Oracle RAC, libs are being used
> from Java to connect).
> 
> On Linux we see the process of Java grow tremendous over the
> size under Solaris. The bigger problem we see is that memory
> does not seem to be freed. Garbage collection shows plenty of
> activity but, the process size stays large and after running a
> load test (which gets the process size high), then wait 30-40 
> minutes, start another load test, the process size grows immediatly,
> which indicates the old memory allocation isn't reused. So
> something is keeping the memory in use, although not activily
> touched (Linux starts to swap it out).
> 
> Now what I am looking for is some form of memory allocation map
> dump. Something which can tell us what objects maybe have things
> allocated, so that I can give our developers some hints what
> direction to look at.
> 
> So, Java Gurus, any idea ? (me prays for a good answer).

Your best bet is probably going to be something like JProbe.
I've used it before on RedHat - pretty snazzy.

Marc.

-- 
Marc Ramirez
Blue Circle Software Corporation
513-688-1070 (main)
513-382-1270 (direct)
http://www.bluecirclesoft.com
http://www.mrami.com (personal)