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From: "Caldarale, Charles R" <Chuck.Caldarale@unisys.com>
To: Tomcat Users List <users@tomcat.apache.org>
Date: Thu, 4 Oct 2012 07:36:17 -0500
Subject: RE: high CPU usage on tomcat 7
Thread-Topic: high CPU usage on tomcat 7
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> From: Kirill Kireyev [mailto:kirill@instagrok.com]=20
> Subject: Re: high CPU usage on tomcat 7

> Perhaps what I need is to have the JVM do garbage collections more=20
> frequently, so that they don't become a huge CPU-hogging ordeals=20
> when they do happen.

That's not how it works.  The amount of time spent in a GC operation is dep=
endent almost entirely on the number of live objects in the heap, not the a=
mount of space being reclaimed.  Having a smaller heap might improve your c=
ache hit rate, but it will have little effect on the time used by GC.

It is highly likely that your webapps have a memory leak.  You need to use =
a profiler and find out what's eating up all that memory.  If you set the h=
eap size to a smaller value, you should be able to provoke the situation ea=
rlier, but it certainly won't fix it.

 - Chuck=20


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