PermGen usage is increasing day by day

[sa081402]

Hi,

In my production Application Server (using Apache tomcat 6.0.28) i was facing some problems after 3/4 days interval. Users were facing extreme slowness during their operations although there were roughly 12-15 users connected with the app server. Creating a new session was also impossible.

We used to restart the Tomcat when such problems occurred. Then I have Change the JVM options
as follows:

-Xms2200m *** previously was: 128m
-Xmx2200m
-XX:PermSize=512m *** previously was: 256m
-XX:MaxPermSize=512m
-XX:+DisableExplicitGC
-XX:+UseParNewGC
-XX:ParallelGCThreads=6

Now, I am getting positive feedback from my users and we didn't need to restart the tomcat anymore. But ! I am observing that my Perm Gen usage volume is increasing day by day while no of users and sessions are not increasing. No new deployment is done.

When i imposed the new JVM set up it's usage was 80MB/512MB. Next day, I found it 92mb/512mb.
After 1 week, today it is 152mb/512mb (only 6 user sessions are there).

Is PermGen usage supposed to increase day by day like this ?
If not, what attempts should i take to resolve this problem.

*I am using Java Melody for monitoring.
*My application is based on Spring 3.0 Framework.

I shall be very much glad if any body give me some feedback regarding this.

Regrds,

Salahuddin

[DarrylBurke]

Moved from Forum Lobby.

Please go through the Forum Rules -- particularly the second paragraph. The other thread you started in 'Introductions' has been removed.

db

[Tolls]

Bit of a guess, since this is something you're going to have to dig into it.
jconsole allows you to look at the PermGen, or you could take a heap dump and use something like Eclipse MAT, or simply jmap -permgen, to see what classes are in there.

What to look for entirely depends on your application.
Hibernate can overgenerate classes, if you've done something odd with it.
Spring possibly.
Or something you've written.
Also String interning.

Obviously there's deploying and undeploying apps, but I'm assuming that's not the case here...