CPU considerations

All IBM® MQ processes of a queue manager are running in a single CPU with some exceptions.

Cache manager process (executable amqcache)
The cache manager process stores all non-persistent messages in main memory. So, if your application profile makes heavy use of non-persistent messages, some scalability can be achieved by configuring IBM MQ to run the cache manager process in a different CPU than the queue manager itself. It is also possible to have multiple cache manager process instances for a single queue manager. You can configure a cache manager process for a set of logical queues given by a queue name pattern.
Set signal manager (executable amqssmgr)
The set signal manager process is involved when your application uses the MQGET SET SIGNAL feature. So, if this feature is heavily used by the application, configuring the set signal manager to run in a different CPU than the queue manager can potentially improve throughput. Like the cache manager, the set signal manager is configured per logical queue name pattern. Note that the set signal manager process can optionally be run in fault tolerant mode as a NonStop process pair. In that case, checkpointing occurs and CPU usage of the backup process is in the same order of magnitude as for the primary. Both CPUs for the set signal manager (primary and backup) can be configured independently.