Is our application or IBM MQ for z/OS running slowly?

Slow applications can be caused by the application itself or underlying software including IBM MQ . Use this topic for initial investigations into slow applications.

If our application is running slowly, this could indicate that it is in a loop, or waiting for a resource that is not available.

Is the problem worse at peak system load times?

This could also be caused by a performance problem. Perhaps it is because your system needs tuning, or because it is operating near the limits of its capacity. This type of problem is probably worst at peak system load times, typically at mid-morning and mid-afternoon. (If your network extends across more than one time zone, peak system load might seem to you to occur at some other time.)

Does the problem occur when the system is lightly loaded?

If you find that degrading performance is not dependent on system loading, but happens sometimes when the system is lightly loaded, a poorly designed application program is probably to blame. This could manifest itself as a problem that only occurs when specific queues are accessed.

Is IBM MQ for z/OS® running slowly?

The following symptoms might indicate that IBM MQ for z/OS is running slowly:

• If your system is slow to respond to commands.
• If repeated displays of the queue depth indicate that the queue is being processed slowly for an application with which you would expect a large amount of queue activity.

We can find guidance on dealing with waits and loops in Dealing with applications that are running slowly or have stopped on z/OS, and on dealing with performance problems in Dealing with performance problems on z/OS.