Why does my Sun JVM fail to initialize when I set PermGen above 128M?

Question

I need to increase my PermGen. Currently I pass the following as command line parameters:

-XX:PermSize=128m -XX:MaxPermSize=128m

This works. If I try to increase the values, however, my JVM fails to initialize, giving me this error:

[2009-06-18 01:39:44] [info] Error occurred during initialization of VM [2009-06-18 01:39:44] [info] Could not reserve enough space for object heap [2009-06-18 01:39:44] [info] [2009-06-18 01:39:44] [395 javajni.c] [error] CreateJavaVM Failed

Specifically, I'm trying to boot up Tomcat in the included JRE6, but I don't think this should matter.

Edit: I'm running Win2k3 VM image with 2GB of RAM. I boot the JVM using the Monitor Tomcat application with the following parameters:

Initial memory pool: 1024, maximum memory pool: 1536

-XX:PermSize=128m -XX:MaxPermSize=128m -XX:+CMSPermGenSweepingEnabled -XX:+CMSClassUnloadingEnabled -XX:+UseConcMarkSweepGC -Dcatalina.home=C:\Program Files\Apache Software Foundation\Tomcat 6.0 -Dcatalina.base=C:\Program Files\Apache Software Foundation\Tomcat 6.0 -Djava.endorsed.dirs=C:\Program Files\Apache Software Foundation\Tomcat 6.0\endorsed -Djava.io.tmpdir=E:\tomcat\temp -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.util.logging.config.file=C:\Program Files\Apache Software Foundation\Tomcat 6.0\conf\logging.properties

Answer 1

Perm Gen is additive to Heap, so check the processes -- you'll need to have 1.5+ GB of your 2G available.

Answer 2

Try to give it a bigger heap with -Xmx512m (this will give 512 MB)

What other memory parameters do you use? How much memory is there in your machine? Are you on a 32-bit or 64-bit machine?

Answer 3

I have 2GB of memory and I run tomcat with settings -Xmx1024m -XX:PermSize=512m -XX:MaxPermSize=512m. This usually runs fine.