clear cache

bimki · **Posted:** Sat May 07, 2005 7:03 pm

hi,

I do an SessionFactory initioalization in init method of my servlet :

Code:

SessionFactory factory;

   public void init(ServletConfig config) throws ServletException {
      try {
         factory = new Configuration().configure("/hibernate.cfg.xml")
               .buildSessionFactory();

...

but sometimes I need to completly clear cache. How can I do it?

This is my sample function, but I don't see any changes in appliction memory usage after executing it :

Code:

         factory.close();
         factory = null;
         System.gc();         
         factory = new Configuration().configure("/hibernate.cfg.xml")
                  .buildSessionFactory();

thanks in advance!

bimki · **Posted:** Sun May 08, 2005 1:04 pm

In short - I need to have "cold" transaction start after some time without restarting tomcat :)

emmanuel · **Posted:** Mon May 09, 2005 6:06 am

closing all sessions and the factory free the resources.
you can do sf.evict*() if you don't want to close it

bimki · **Posted:** Mon May 09, 2005 7:01 am

does just calling session.close clear the cache?

steve · **Posted:** Mon May 09, 2005 10:03 am

Session.close() clears the session cache.

SessionFactory.close() calls the CacheProvider's stop() method. It is up to each CacheProvider what they want to do here, so it depends on which cache provider you are using.

bimki · **Posted:** Mon May 09, 2005 7:56 pm

This is my new solution :

Code:

         factory.evictQueries();
         factory.close();
         factory = null;
         
         factory = new Configuration().configure("/hibernate.cfg.xml")
               .buildSessionFactory();

is after calling this code all the cache free?

Greetings

steve · **Posted:** Mon May 09, 2005 9:19 pm

SessionFactory.close() calls the CacheProvider's stop() method. It is up to each CacheProvider what they want to do here, so it depends on which cache provider you are using.

bimki · **Posted:** Tue May 10, 2005 4:11 am

I'm using org.hibernate.cache.HashtableCacheProvider.

steve · **Posted:** Tue May 10, 2005 10:42 am

With HashtableCacheProvider, references to the individual Maps are not maintained by the provider. So they are explicitly not cleared. However, on SessionFactory shutdown all references to them would get cleaned up and they would become eligible for garbage collection.