Exception in thread ""http-apr-8080"-exec-43" java.lang.OutOfMemoryError: PermGen space Error

Question

I made a dynamic web project in Eclipse with hibernate frameworks(servlet).
The first run is ok.
But run it for more times, i get this Exception

Tomcat v7.0 Server at localhost, jdk1.7.0_17. 
On Win2007 32 bits with 4GB of RAM

check this out http://stackoverflow.com/questions/11646483/jboss-7-java-lang-outofmemoryerror-permgen-space The same applies to your case — MaVRoSCy, Jan 08 '15 at 06:34
While this might well be a duplicate of the given question it could also be the hibernate-issue mentioned in may answer and not be related to tomcat in any way... — piet.t, Jan 08 '15 at 09:20

score 0 · Answer 1 · edited May 23 '17 at 12:28

This could be happening if you have a low memory allocated for the VM. Increase the memory(PermGen) available for the VM.

If you still have an issue after increasing the memory, then attach a profiler and inspect to see if you have any memory leaks.

score 0 · Answer 2 · answered Jan 08 '15 at 07:33

I can think of two problems, depending on what you mean with "run it for more times":

If it is "after multiple deployments" you might have run into menmory-leak with classloading. Tomcat 6 definitely had some trouble with this, don't know for sure about tomcat 7.
If it is "after multiple invocations" of the same deployed application this could be a bug in your application with handling the SessionFactory/EntityManagerFactory. As a rule of thumb make sure you only create one SessionFactory/EntityManagerFactory over all the lifetime of your aplpication. Each invocation should only create a Session/EntityManager from the existing factory.

2 Answers2