How to limit the number of MDBs connected to a queue in wmq.jakarta.jmsra.rar

[Igor Koulikov]

Hi all,

how can I limit the number of MDBs connected to particular queue in Wildfly 34 connected 

to IBM MQ9.3 using jakarta.jms?

Thank you

[Emmanuel Hugonnet]

I can see a maxConnections parameter on the WMQ JCA connector.
When configuring number of MDBs concurrently processing messages, two parameters needs to be considered
 * mdb-strict-max-pool - The number of MDB instances available to concurrently receive messages from the JCA RA's sessions - configured in
EJB subsystem
 *maxSession - The number of sessions the JCA RA can use concurrently to consume messages - configured by MDB Activation config property

Maximal number of concurrently processed messages equals to minimal value of these parameters.
In case number of MDBs needs to be adjusted, admin needs to update/check both parameters (located in different places)
It would be nice to align size of mdb-strict-max-pool and maxSession activation config property.
If maxSession is not specified, size of mdb-strict-max-pool should be used.

Emmanuel

Le 22/08/2025 à 19:07, Igor Koulikov a écrit :
> IBM MQ9.3