Re: [jboss-as7-dev] Getting on the same page with @Clustered @Singleton

From: "Radoslav Husar" <rhusar(a)redhat.com&gt; To: jboss-as7-dev(a)lists.jboss.org, "David Lloyd" <dlloyd(a)redhat.com&gt;, "Paul Ferraro" <pferraro(a)redhat.com&gt; Sent: Wednesday, December 7, 2011 10:50:35 AM Subject: [jboss-as7-dev] Getting on the same page with @Clustered @Singleton Hi guys, I just want to sync up with everyone what's the plan on EE6's @Singleton running on multiple JVMs in 7.1*. There is a common misconception that @Singleton is acting at cluster level. This is nay. The EE spec says: A Singleton session bean is a session bean component that is instantiated once per application. In cases where the container is distributed over many virtual machines, each application will have one bean instance of the Singleton *for each JVM*. However the concept of @Clustered @Singleton where there is only 1 failure-resistant bean instance within the cluster replicating state does make a lot of sense. Having to sync on the persistence level sounds dreadful. In one sense it is the successor of AS 5's singleton-ha which was deployment-level mechanism. Is is possible to have this even though it is kind of violating the EE spec? David is requesting to fail the deployment of such: https://issues.jboss.org/browse/AS7-2887 Does it mean that we wont have it in 7.1? Maybe later? Cheers, Rado * EAP 6.0 -- Radoslav Husar JBoss QE _______________________________________________ jboss-as7-dev mailing list jboss-as7-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/jboss-as7-dev