In concurrent processing, Integration Server processes messages received from the JMS provider in parallel. That is, Integration Server processes as many messages for the JMS triggers as it can at the same time, using a separate server thread to process each message. Integration Server does not wait for the service specified in the routing rule to finish executing before it begins processing the next message. You can specify the maximum number of messages Integration Server can process concurrently. This equates to specifying the maximum number of server threads that can process messages for the JMS trigger at one time.

Concurrent processing provides faster performance than serial processing. Integration Server processes the received messages more quickly because it can process more than one message for the trigger at a time. However, the more messages Integration Server processes concurrently, the more server threads it dispatches, and the more memory the message processing consumes.

Additionally, for JMS triggers with concurrent processing, Integration Server does not guarantee that messages are processed in the order in which they are received.

A concurrent trigger can connect to the JMS provider through multiple connections, which can increase trigger throughout. For more information about multiple connections, refer to Using Multiple Connections to Retrieve Messages for a Concurrent JMS Trigger.