[jira] Resolved: (AMQ-758) Message Groups disables server side JMS session pooling

["james strachan (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/activemq/browse/AMQ-758?page=all ]
     
james strachan resolved AMQ-758:
--------------------------------

    Resolution: Won't Fix

Closed for now as this bug is an effect of the design of Message Groups - they are meant to implement single-threaded processing of a single message group.

> Message Groups disables server side JMS session pooling
> -------------------------------------------------------
>
>          Key: AMQ-758
>          URL: https://issues.apache.org/activemq/browse/AMQ-758
>      Project: ActiveMQ
>         Type: Bug

>   Components: Broker
>     Versions: 4.0
>  Environment: XP, ActiveMQ 4.0 release, Lingo 1.1, Spring 2.0
>     Reporter: Sanjiv Jivan
>  Attachments: lingocluster.zip
>
>
> Specifying Message Groups on the client causes serialized/ single threaded processing of messages on the server side even when server side session pooling is configured.
> Please find attached  sample code along with a JUnit test "MessageGroupTests" that demonstrates the issue. My sample is based on Lingo. The client calls an async method solve(scenarioName) and receives progress callbacks. When the cleint calls cancel(scenarioName) during a solve, the cancel method on the server side should be received and stop the running solve. Since a single JMS session evexcutes message listeners serially, I've configured a JMS server session pool of size 20 using Spring's DefaultMessageListenerContainer class.
> I've configured use of a message group via a Lingo marshaller class org.sanjiv.lingo.client.MessageGroupMarshaller. This class basically sets the JMS header  "JMSXGroupID" to the "scenarioName" in question so that when a cluster of servers are running, the cancel(scenarioName) call is directed to the server that had solve(scenarioName) called for a given "scenarioName".
> The issue is that when the message groups are enabled using the MessageGroupMarshaller, the cancel(scenarioName) call blocks and waits for the async solve(scenarioName) method to complete on the server (which is not the right behaviour). Disabling message groups by commenting out the client side MessageGroupMarshaller marshaller in org/sanjiv/lingo/test/messageGroupContext.xml results in the call being excuted correctly.
> I see that the docs for message groups say that message order is preserved, however that should not require that the second message blocks till the first message completes. Only the order in which the listeners are executes should be guaranteed to be the order of message receipt.
> Let me know if you have any questions.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
   https://issues.apache.org/activemq/secure/Administrators.jspa
-
For more information on JIRA, see:
   http://www.atlassian.com/software/jira