An update. I noticed in the stack trace that it seems to be the *production* of messages that get the exception "Unable to complete sending the message: Only one thread may use a JMS Session at a time." - not the *consumption*. I also only showed you the first part of the route (cause I didn't think the rest mattered). What I do is basically reading xml messages from one queue, transforming them and the sending them to another queue.
Moreover, one incoming message may end up creating more than one (in this case 3) out messages. I'm using a splitter to accomplish this. In pseudo code the route looks like this: from(sjms:...).threads(10).process(converting...).split().to(sjms:...); If I set consumerCount=10 on the consumer endpoint AND use threads(10) then I can see that more threads are created but I get the "Only one thread may use ..." exception. Now, if I also set the producerCount=10 on the producer endpoint then this exception goes away and my route works. Not exactly sure why this works. If anyone could explain the relationship between consumer/producer count and threads I would appreciate it. A theory of mine is that there must be at least as many consumers/producers as there are threads or there is a risk that two threads will try to use the same consumer/producer. If there is a one-to-one relationship between consumer/producer and JMS session then this could explain the exception. But this still sounds weird. If there is a pool of consumers/producers then the thread should try to acquire one from the pool. If no consumer/producer is available then the thread should wait until one is available - not try to use one that is in use by another thread. Also, although I can get my route to work this way, I get no better throughput than if I only use one thread. I get the exact same throughput and my CPU is basically idling. Obviously I'm not doing this right. Do I also need multiple connections to the JMS server? Could this affect the concurrency? /Bengt 2014-03-17 8:39 GMT+01:00 Bengt Rodehav <be...@rodehav.com>: > I've now tried just using consumerCount on the endpoint without using > threads(). However, it doesn't make it multithreaded. Only one thread is > started for the route. > > Any other ideas? Has someone used sjms with a multithreaded consumer? > > /Bengt > > > 2014-03-14 17:42 GMT+01:00 Bengt Rodehav <be...@rodehav.com>: > > Ok - thanks. I have tried it but only together with threads(). I didn't >> realize that it might create threads on its own. >> >> /Bengt >> Den 14 mar 2014 17:26 skrev "Claus Ibsen" <claus.ib...@gmail.com>: >> >> Hi >>> >>> I think you should use the consumerCount option on the endpoint instead >>> >>> On Fri, Mar 14, 2014 at 5:10 PM, Bengt Rodehav <be...@rodehav.com> >>> wrote: >>> > I'm using Camel 2.12.3 and the sjms component for communicating with >>> > Weblogic JMS. >>> > >>> > Everything works fine when I use a single thread. However, to increase >>> > throughput I want multiple threads to read messages from the queue. >>> > >>> > I've done this by using the "threads()" method: >>> > >>> > from(sjms:...).threads(10).... >>> > >>> > However I get an exception as follows: >>> > >>> > java.lang.Exception: Unable to complete sending the message: Only one >>> > thread may use a JMS Session at a time.:Only one thread may use a JMS >>> > Session at a time. >>> > at >>> > >>> org.apache.camel.component.sjms.producer.InOnlyProducer.sendMessage(InOnlyProducer.java:135)[129:org.apache.camel.camel-sjms:2.12.3] >>> > at >>> > >>> org.apache.camel.component.sjms.SjmsProducer.process(SjmsProducer.java:180)[129:org.apache.camel.camel-sjms:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.SendProcessor.process(SendProcessor.java:110)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:72)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:398)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline.process(Pipeline.java:118)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline.process(Pipeline.java:80)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:398)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.MulticastProcessor.doProcessSequential(MulticastProcessor.java:574)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.MulticastProcessor.doProcessSequential(MulticastProcessor.java:507)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.MulticastProcessor.process(MulticastProcessor.java:216)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Splitter.process(Splitter.java:98)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:72)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:398)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.ChoiceProcessor.process(ChoiceProcessor.java:111)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:72)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:398)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:191)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline.process(Pipeline.java:118)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline.process(Pipeline.java:80)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline.process(Pipeline.java:118)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline.access$100(Pipeline.java:43)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.Pipeline$1.done(Pipeline.java:136)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> org.apache.camel.processor.ThreadsProcessor$ProcessCall.run(ThreadsProcessor.java:83)[106:org.apache.camel.camel-core:2.12.3] >>> > at >>> > >>> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)[:1.6.0_32] >>> > at >>> > >>> java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)[:1.6.0_32] >>> > at java.util.concurrent.FutureTask.run(FutureTask.java:138)[:1.6.0_32] >>> > at >>> > >>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)[:1.6.0_32] >>> > at >>> > >>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)[:1.6.0_32] >>> > at java.lang.Thread.run(Thread.java:662)[:1.6.0_32] >>> > >>> > What exactly does this mean and how can I consume messages via sjms >>> using >>> > multiple threads? >>> > >>> > /Bengt >>> >>> >>> >>> -- >>> Claus Ibsen >>> ----------------- >>> Red Hat, Inc. >>> Email: cib...@redhat.com >>> Twitter: davsclaus >>> Blog: http://davsclaus.com >>> Author of Camel in Action: http://www.manning.com/ibsen >>> Make your Camel applications look hawt, try: http://hawt.io >>> >> >
