VM-Size in Windows task manager increases constantly

[ms2]

I got a big problem. Please give me some hints how to solve it. I read a lot of threads about it here, but no solution.

My system is:

P IV, 4GB mem (no swap to not delay the problem)
Windows 2003 Server x64
SUN JDK 1.5.0-07 for AMD x64
JBoss 4.04
My own stateful session bean and two servlets of my own

JBoss/JVM parameter:
set JAVA_OPTS=%JAVA_OPTS% -Xms2048m -Xmx2048m
set JAVA_OPTS=%JAVA_OPTS% -XX:PermSize=150m -XX:NewRatio=3

My problem is:
To stress test my bean I create approximately 600 instances. One hour after the start the windows task manager tells me a VM-Size of 2.5 GB. That?s okay. Visual GC 3.0 tells me the following:

PermSize: 50MB (ok)
OldGen: 300MB (ok) (after 2 collections)
Survivor ½: 130MB (ok)
Eden: 170MB (ok)

Everything is okay.

After 30 hours Visual GC:

PermSize: 50MB (ok)
OldGen: 300MB (ok) (after 500 collections)
Survivor ½: 8MB (interesting, but still ok for me)
Eden: 33MB (interesting, but still ok for me)

The Problem is now windows task manager for java.exe

MemUsage: 1.6GB (ok)
PeakMemIsage: 1.6GB (ok)
VM Size 3.5GB (and increasing: very big problem)

When VM-Size reaches 3.8GB, java.exe crashes.

IMHO JVM?s internal heaps are okay but there must be an internal error in its memory management. It?s not that I want memory returned to the OS but the JVM should detect a lack of fresh memory and not allocate anymore.

I also think that there is no benefit in changing Xms Xmx Xss (the well known switches). I tried without success.

Is it possible that this is a special problem of the x64 JVM? With 32 Bit I run onto other limitation.

Any help is welcome

Thanks in advance.

[ms2]

I found the problem. It's inside the commons-fileupload-1.1.1 library (or my wrong usage of it) which creates a leaking File-Object each time a HTTP-Request is parsed.

See in DiskFileItem.java:

public OutputStream getOutputStream() throws IOException
{
. if (dfos == null) {
. . File outputFile = getTempFile();
. . dfos = new DeferredFileOutputStream(sizeThreshold, outputFile);
. }
. return dfos;
}