6 Replies Latest reply: Jul 11, 2012 7:53 PM by Brad Douglas RSS

    Stateful session bean method invocations serializied on common lock

    Brad Douglas Newbie

      Hi all,

       

      I'm seeing odd locking behavior in JBoss AS 6.1 I'm hoping someone can give some insight into - and how to fix/work around it.

       

      We've got a Seam app and have a problem with a stateful session bean that is backing some EL on a JSF page.   Under load / stress testing using jmeter wirth 50 http sessions and I'm noticed we're not getting any concurrency in JBoss and guessed that something was serializing the calls across the JVM.

       

      I've done some digging and attached a full thread dump.  Looking at it you'll see 47 out of 50 of http-0.0.0.0-8080-XX threads waiting for the same lock (0x23471e11).  This lock appears to be a system wide lock on the stateful bean rather than a session scoped lock.

       

      Here is the definition of the stateful bean:

       

      @SuppressWarnings("unchecked")
      @Stateful
      @Name("documentGenerationBean")
      @Scope(ScopeType.CONVERSATION)
      public class DocumentGenerationActionBean extends MaintenanceActionBean implements DocumentGenerationAction {
          .....
      }
      

       

      Any help is greatly appreciated - even ideas about where to look for more info.

       

      Thanks,

      Brad