[jboss-user] [Clustering/JBoss] - Re: ConcurrentModificationException during session serializa

[smarlow@redhat.com]

I see, so we are obtaining the RL for the application (held while the application request is running).  This avoids the cooperative locking scheme that would of required the application to lock on the sessionFacade object.

Some potential performance issues that could challenge this approach.

1.  During http session replication, further http requests (from users that are involved with the replication) will block (at least while the session level write lock is held for the replication).  

2.  When a http request is completing that has modified http session attributes, the replication will be delayed until the write lock can be obtained.  This could introduce unexpected performance delays.

3.  Are there additional performance implications for synchronous replication?  If the user waits in the browser for the replication to complete, they could be waiting a long time, depending on when the write lock can be obtained.



View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4240439#4240439

Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&p=4240439