Would like to share something as you mentioned ‘multi-threading’
MQ Listener is single threaded ( underlying, it will create a single TCP/IP connection ESTABLISHED state between MQ server and IS MQ Adapter when you enable the listener). Through this thread, it reads the messages from the queue like a stream. If you have 2 Integration servers connected to MQ, there will be 2 TCP/IP connection. Messages flow through these in much higher speed.
Listeners can be associated with MQ Transactional connection or MQ Non-Transactional connection. As the name indicates, transactional provides guaranteed message delivery (from MQ to IS) and non-transactional is like fire-and-forget.
As every one mentioned, if you need faster processing, it can achieved only with Adapter notification of type ASYNC.
Your need of multiple requests to be processed concurrently starts with ASYNC adapter notification, followed by other tunings if necessary ( connection type, transaction type, more connections on the listener, trigger properties etc., )
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