Performance and disk failover considerations on IBM i

If you use a large number of persistent messages or large messages in your applications, the time spent writing these message to disk becomes a significant factor in the performance of the system.

Ensure that you have sufficient disk activation to cope with this possibility, or consider a separate Auxiliary Storage Pool (ASP) in which to hold your queue manager journal receivers.

You can specify which ASP your queue manager library and journals are stored on when you create your queue manager using the ASP parameter of CRTMQM. By default, the queue manager library and journals and IFS data are stored in the system ASP.

ASPs allow isolation of objects on one or more specific disk units. This can also reduce the loss of data because of a disk media failure. In most cases, only the data that is stored on disk units in the affected ASP is lost.

You are recommended to store the queue manager library and journal data in separate user ASPs to that of the root IFS file system to provide failover and reduce disk contention.

For more information, see Backup and recovery.