What to do when one of your page sets becomes full

We can find out about the utilization of page sets by using the WebSphere MQ command DISPLAY USAGE. For example, the command:

  DISPLAY USAGE PSID(03)

displays the current state of the page set 03. This tells you how many free pages this page set has.

If you have defined secondary extents for your page sets, they are dynamically expanded each time they fill up. Eventually, all secondary extents are used, or no further disk space is available. If this happens, an application receives the return code MQRC_STORAGE_MEDIUM_FULL.

If an application receives a return code of MQRC_STORAGE_MEDIUM_FULL from an MQI call, this is a clear indication that there is not enough space left on the page set. If the problem persists or is likely to reoccur, do something to solve it.

We can approach this problem in a number of ways:

• Balance the load between page sets by moving queues from one page set to another.

• Expand the page set. See How to expand a page set for instructions.

• Redefine the page set so that it can expand beyond 4GB to a maximum size of 64GB. See Defining a page set to be larger than 4GB for instructions.