What can be done with 'PermGen out of space' exception in Tomcat-Spring-Hibernate web application?

Question

We have an web application that uses Spring-Hibernate to persist registered users data in Oracle database. The application works fine in development environment, but when we

Answer 1

I have seen this problem with Hibernate (used without Spring). The issue there was that we were creating an instance of a SessionFactory for each user request rather than creating a single instance for the lifetime of the application.

I used the YourKit profiler to investigate this and discover the issue.