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Java Heap dump Size and Resident Memory(RES) Size

krishna bulusu
Ranch Hand

Joined: Aug 28, 2006
Posts: 185

We have our production running under Red ha Linux environment. We are using JDK 1.5.19 version. We are using Tomcat 6.0.18 as our web server.
What we observe is, the heap dump size and the resident memory sizes are not matching at all. If the Resident memory(RES) size is at 2GB, the heap dump size is 220MB. We are having a huge performance hit due to this.
Is this normal pattern or are we facing memory leak? We have analyzed the heap dump and fixed few issues in it. However, what we think is, memory is leaking not in the heap but some where else. Please can somebody help us on this.

PS: Sorry for the re post... Nobody is answering this on Java forum

Thanks&Regards, Krishna.
SCJP1.4, SCWCD1.4, SCBCD 5.0
Sandeep Sanaboyina
Ranch Hand

Joined: Dec 14, 2009
Posts: 72
You have not mentioned the heap size that you are providing for your applications.

I think the heap dump does not have to match with the resident memory.

They say you have to be the first, the best or different. I say, is it too much to ask for all three.
SumitPal Pal

Joined: Aug 31, 2010
Posts: 22
Yes we would like to help you out - but I think we need more info from your side on this.
Your JVM Parameters would be helpful.
Also the heapdump

I do agree with the previous post that the HeapDump and RES Size need not be equal.

Use a profiler would be the best way to correct memory leaks.
I have used YourKit extensively but there are others in the market too
I agree. Here's the link:
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