Issues with connection creating using JMSContainerInvoker an

[timfox]

I have traced out from JBoss Messaging the places in the JCA/MDB container code that create JMS connections to handle MDBs.

I deployed an MDB and sent a message to it from a client application.

When using JMSContainerInvoker, 3 connections were created by the AS.

1) To handle the DLQ

2) For the connection consumer

3) To create the session that is used to handle the delivery of the message

This all works happily with a non clustered JMS provider like JBoss MQ, since the connections will always be created on the same server - this is because JBoss MQ is a HA Singleton and there is only ever one active server in the cluster at any one time.

However it causes major issues for JBoss Messaging, (and probably for any other more advanced messaging provider which has many active nodes in the cluster at any one time), since subsequent connections will actually be created on different servers.

This means that connection 2) and 3) wil typically be on different servers (we round robin between servers) - which means that any messages received on 2) will get acked on 3), which wil result in the server barfing since it won't know about the messages (they came from a different server).

The new(er) JCA inflow code basically has the same problem, meaning it will only really work with single server jms providers (i.e. JBossMQ).

I can't reallyunderstand why the JCA/MDB container doesn't use the same connection for 2) and 3).

The upshot of this, is that, when using MDBs with JBoss Messaging (or probably any other modern JMS provider that has load balancing) we must turn off load-balancing.

This means that all MDBs will be creating their connections to the same server in the cluster and we will have a poor use of the cluster.

How easy would it be to fix the ConnectionConsumer / JCA inflow so it uses the same connection for 2) and 3)?

We really need MDBs to be able to take advantage of clustered JMS.

[timfox]

I should add that this is only really a problem when deploying MDBs in JBoss AS that are consuming from a *remote* JMS provider (e.g. another JBossAS instance).

For deploying MDBs that consume from a colocated JMS provider (which is the standard deployment scenario) this is not an issue since you would not want load balancing anyway.

[adrian.brock]

There is no seperate connection for (3).

I don't know what you are seeing, but the sessions for delivery must be
under the same connection as the connection consumer.

SHOW EVIDENCE!

The use of the DLQ connection (1) is really pretty redundant since it is only
for JMS implementations that don't have DLQs themselves (like JBossMQ).

[timfox]

Evidence is on its way... I am very busy this week, but will get round to it next week :)

[weston.price]

SHOW EVIDENCE!

Please do. I can't quite understand what you are seeing as the Session created always originates from the original connection.

[ramazanyich]

Is there any progress on this issue ? We are really need clustered factories for MDBs