How to analyze PermGen contents?

java permgen
Daniel picture Daniel · May 16, 2010 · Viewed 24.6k times · Source

I want to get a dump of the PermGen to see why it is filling. Is there a way to analyze this? I already know about the common suspects like log4j, tomcat webapp reloading etc, but I have some custom proxy generation code in my application, too, and just want to look under the hood.

Is this possible somehow?

Answer

Puneet picture Puneet · Oct 2, 2011

The PermGen normally consists of the string literal pool and loaded classes. To answer part of your problem, i.e. the string literal pool I wrote a utility to print a running JVM's string literal pool. It is available here:

https://github.com/puneetlakhina/javautils/blob/master/src/com/blogspot/sahyog/PrintStringTable.java

It is based on PermStat, which is the class used to print permgen stats by the jmap tool.

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