Establishing performance periods for DDF threads

You can establish performance periods for DDF threads, including threads that run in the WLM-established stored procedures address space.

About this task

By establishing multiple performance periods, you can cause the thread's performance objectives to change based upon the thread's processor consumption. Thus, a long-running unit of work can move down the priority order and let short-running transactions get in and out at a higher priority.

Procedure

To design performance strategies for these threads:

  • Take into account the events that cause a DDF thread to reset its z/OS® performance period.
  • Use velocity goals and use a single-period service class for threads that are always active.
    Because threads that are always active do not terminate the enclave and thus do not reset the performance period to period 1, a long-running thread always ends up in the last performance period. Any new business units of work that use that thread suffer the performance consequences. This makes performance periods unattractive for long-running threads.