Hi, I am running an app on JBoss 3.2.3 (SPARC 1.4.1_05-b01 VM). The application uses a number of MDBs that are a sink of P2P JMS messages. I have noticed that the call to sender.send() can take a long time to return, and the length of time appears to be linked to the processing duration of the MDB onMessage() method (i.e. the call to send() appears to be almost synchronous wrt to the MDB that processes the message).
I am using the JVM invocation layer because everything occurs within the EJB container. The MDB components are set to Bean managed trx management, and AFAIK this should result in the container auto acknowledging receipt of messages by the MDB. The flow of control is like this; 1. A Stateless Session EJB component sends a message to a queue Q1 2. An MDB instance MDB1 is the recipient of Q1. 3. MDB1 does its processing and then sends an arbitrarily configurable number of messages to a queue Q2. This thread then does a wait(). 4. One or more MDB instances MDB2 are the recipient(s) of Q2. 5. Each MDB2 instance does its processing and then sends a message to queue Q3. 6. An MDB instance MDB3 receives the message Q3. 7. MDB3 does its processing, and then checks if it is the last thread of control that were set off as a result of the messages in step 3. If so it uses notify() to wake up the thread that is waiting in 3. 8. MDB1 checks whether it needs to send any more messages, and if so return to step 4. A pseudo sequence diagram is as follows; | SSB -- M1 --> Q1 --> MDB1 -- M2 --> Q2 --> MDB2 -- M3 --> Q3 --> MDB3 | -- M2 --> Q2 --> MDB2 -- M3 --> Q3 --> MDB3 | -- M2 --> Q2 --> MDB2 -- M3 --> Q3 --> MDB3 | The reason that it is designed this way is in the interests of flow control, and also to be able to take advantage of an SMP host with respect to the processing of M2 that can be done in parallel. Because it takes so long for the sender.send() call to return in MDB1 this benefit is reduced though. Thanks and regards, Andrew View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=3851468#3851468 Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&p=3851468 ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl _______________________________________________ JBoss-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-user
