Tuning IBM MQ for replication performance

Because IBM® MQ is the transport mechanism for replication and publishing, you must tune your queue managers and queues to maintain optimal performance.

Message limits for queues (MAXDEPTH)
In a high-volume replication environment, you must pay particular attention to the number of messages that each queue is set up to hold. This number is set by the MAXDEPTH parameter.
Queue indexing (z/OS)
Receive queues on the target system should be created with an index to speed pruning of the queue after transactions are applied. You set the INDXTYPE parameter when you define a local queue.
Queue buffer pools (z/OS)
You can improve performance on z/OS® by creating a larger buffer pool for queues that are expected to carry a high message load. The transmission queue at the source and the receive queue at the target are likely to have the heaviest and most consistent replication or publishing message load.
IBM MQ logging
The queue manager logs all persistent messages in active and archive logs in a manner similar to Db2®. Extra overhead is required for message logging, which can affect performance.
Channel parameters
You can tune the channel batch size and interval to improve replication performance. For z/OS, you can also adjust the channel parameters to improve performance.
Maximum uncommitted messages (MAXUMSGS)
The Q replication and Event Publishing programs put and get messages from queues within a synch point, so the MAXUMSGS parameter might be a factor in your IBM MQ tuning. MAXUMSGS is a queue manager parameter that limits the number of messages that can be put on queues or retrieved from queues within a synch point.

Parent topic: Q Replication tuning

Related concepts

Required settings for MQ objects
Storage requirements for MQ

Related information

IBM MQ performance between z/OS and Linux using Q Replication processing model