Spring + Hibernate application not releasing memory
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We have created a spring web app. using:
 
* Spring 3.1.0
* Hibernate 3.5.4 final
* tomcat 6.24
 
The application is reasonably heavy, we are sending about 1000 contacts per user request.
We tested our application with 9 concurrent users with repeated requests and profiled with visual vm the results are as follows:
 
![enter image description here][1]
 
 
  [1]: http://i.stack.imgur.com/dAnaP.png
 
Looking at the results, the high peaks are the repeated requests and the lower points are when all requests are stopped. The first ~200MB of memory does not seem to be released at all. Is spring actually just this heavy or do I have a potential memory issue? The release version of this web app will potentially handle much more users.

I have similar results testing on tomcat 7 as well.
