Hi It is quite complicated, what's your real goal (not the technical solution)? It looks like timers + @async would be enough Le 23 nov. 2013 14:17, "Leonardo K. Shikida" <[email protected]> a écrit :
> Hi > > First of all, I'd like to thank this community for all the help during > these months. > > I've noticed a significant performance/stability improvement from 1.5.2 to > 1.6.0. Good job. > > I am experiencing some fine tuning issues, so I'd like to ask you for some > advice. > > My app is simple as that: it's a web app that allows the user to manage > several timers (quartz). Each time the quartz cron job is triggered, the > @Timeout method just queues a job (activemq). Then some MDBs consume that > job (it's a long running job). So producers can be much faster than > consumers. Both JMS and Quartz are backed by an Oracle XE instance. > > JMS messages are very small and must never be ignored or discarded. > > One thing I've noticed is that I'll have to control the quartz jobs myself, > because even if I pause the timers, when the server is restarted, timers > are restored and restarted automatically, probably because the JEE spec > says it must be this way. I am considering the idea of not persisting > quartz, but only some job metadata, and in the next restart, some EJB > annotated with @Start can restart or not each timer. > > Another thing I've noticed is that when I have 10 quartz jobs that trigger > a new job every minute (I was trying every second, but resources were being > quickly consumed, although I'd be happy to find some config that could > allow this in a 8GB RAM machine) would be enough to make my web app not > responsive, hanging forever. That's why I am asking in another email how > can I specify different pools for different EJBs. Sounds to me that > something is really not configured well, because 10 jobs submitting a JMS > message each second should not be a very big deal I guess. > > Since the bottleneck seems to be in the producer side, I've tried to change > the producer EJB (that has the @Timeout method) from @Stateless to > @Singleton+@Lock(LockType.WRITE) but it seems I've just moved one problem > from one side to another. > > Another thing I've noticed that adding a producerFlowControl="false" to > activemq.xml could help, but it was not enough. > > I've also noticed that consumers work better if I add a Thread.sleep(50) > before consuming at onMessage(Message msg), maybe giving some time for JMS > to release locks (I think). > > Last but not least, I've experiencing some strange problems probably > related to the classloader, and I've removed xerces-impl-2.11.0.jar from > eclipse factory path (java compiler -> annotation processing -> factory > path, to generate openJPA metamodel classes for Criteria using > openjpa.metamodel=true). I am adding all tomee jars, but I would like to > restrict to the barely necessary classes. I am using oracle JVM 7. > > I am not sure if this is also a bottleneck (it seems to be working anyway) > but I am keeping both the EntityManager, TimerService and JMS queue > centralized in a @ApplicationScoped bean, so everytime a EJB needs one of > them, they just retrieve from this "global" bean. > > So the idea here is to receive criticisms and suggestions. They will be > very welcome. > > TIA > > Leo >
