Stability and Performance - Oracle WebLogic Server 12c Advanced Administration - page 235

5. Type jmsAppMaxThreads in the Name text field and 1 in the Count text field. Click
on the Next button.
6. Select the All servers in the cluster radio button from the PROD_Cluster option and
click on the Finish button.
7. Click on the New button again and select the Work Manager radio button. Click on
the Next button.
8. Type jmsAppWM in the Name text field and click on the Next button.
9. Select the All servers in the cluster radio button from the PROD_Cluster option and
click on the Finish button.
10. Click on the newly created jmsAppWM work manager. Select the
jmsAppMaxThreads option from the Maximum Threads Constraint drop-down
menu. Check the Ignore Stuck Threads checkbox and click on the Save button.
11. Click on the Activate Changes button to finish.
Now associate the jmsAppWM work manager to be used by the JMSApp application, by editing
the file descriptor META-INF/weblogic-ejb-jar.xml :
1. Edit the file META-INF/weblogic-ejb-jar.xml and add the tag <dispatch-
policy> :
<weblogic-enterprise-bean>
<ejb-name>QueueMDB</ejb-name>
<message-driven-descriptor>
...
</message-driven-descriptor>
<dispatch-policy>jmsAppWM</dispatch-policy>
</weblogic-enterprise-bean>
2. Save and repack the JMSApp application.
3. Redeploy the JMSApp application.
How it works...
The QueueMDB now consumes the JMS Queue with a maximum of 1 thread instead of 16.
Controlling the JMS Queue consumers is important to prevent too much concurrency in the
environments with a lot of JMS Queues. In a scenario where a hypothetic application uses 20
JMS Queues and there is a large backlog of messages in them, WebLogic can use up to 320
threads (20 Queues * 16 consumer threads).