Message thresholds
If the number of messages waiting to be processed exceeds the high message threshold that you set, the application server limits the addition of new messages in the processing queues.
Depending on your message requirements, you might want to type a higher message threshold value. To determine an optimal message threshold setting, you can monitor the messaging in/out queues and the impact of the message threshold setting on system performance. For example, you can decrease the threshold value if a higher value is degrading system performance.
If you decide to change the high message threshold setting after the initial configuration, you must open the Additional Properties menu in the administrative console. You can then change the threshold value for each child configuration.