Current-plan recovery processing

About this task

When IBM Z Workload Scheduler suspects that the active current plan is unusable, it automatically carries out recovery processing. IBM Z Workload Scheduler uses the alternate current plan or the new-current-plan data set (EQQNCPDS) and the active job-tracking log to create a current plan that is fully up-to-date. Here is a step-by-step description of the current plan recovery process:
  1. The current plan is locked to prevent updates from job-tracking events and dialog users.
  2. The active current plan is erased.
  3. The alternate current plan or new current plan is copied to the active current plan. Indicators in the checkpoint data set determine which of the two are actually used. This is explained further in Current-plan processing at IBM Z Workload Scheduler startup.
  4. The identity of the active job-tracking log is obtained from the checkpoint record. Every record of the current JT log is used to update the active current plan.

    If recovery is performed from the new current plan, the current JT log and the JT archive log are used to reapply the events that have occurred since the new current plan was created.

  5. The active current plan is now up-to-date. A current plan backup is performed.
  6. Normal IBM Z Workload Scheduler processing starts or continues.
Current-plan recovery is performed for the following situations:
  • During IBM Z Workload Scheduler startup, if the current plans (CP1 and CP2) are not equal.
  • During IBM Z Workload Scheduler startup, if CURRPLAN(NEW) has been specified on the JTOPTS statement.
  • During normal IBM Z Workload Scheduler processing, if the active current plan becomes damaged or is not accessible.
If the data space CX file becomes unusable, IBM Z Workload Scheduler performs these recovery actions:
  1. The current plan is locked to prevent updates from job-tracking events and dialog users.
  2. The CX data space is deleted.
  3. The CX DASD file is copied to a new data space.
  4. The identity of the active job-tracking log is obtained from the checkpoint record. Records in the current JT log are used to update the data space.
  5. The data space file is now up-to-date. A current plan backup is performed.
  6. Normal IBM Z Workload Scheduler processing starts or continues.

When IBM Z Workload Scheduler performs recovery from the new current plan, the EQQNCXDS file is copied to EQQCXDS, a data space is created, and events are reapplied using the JT archive log and the current JT log. The data space is refreshed to the DASD file during the subsequent current plan backup.

If the CX DASD file becomes unusable, follow the instructions in Recovering from errors on the current-plan-extension data set.