Determining main eligibility

Main eligibility is determined in the following stages:
  1. Input service determines the mains that can execute the job when either the SYSTEM or SYSAFF parameter on the JOB control statement, or the SYSTEM parameter on the //*MAIN control statement, and the job class are analyzed.
  2. JES3 MDS selects mains by location of non-shared devices and permanently resident volumes and data sets.
  3. The assignment of removable devices by the job can again restrict the mains eligible to run a job.
  4. The availability of the job's scheduling environment can restrict the mains that are eligible to run a job.

For these reasons, jobs in a JES3 loosely coupled complex are selected for execution by processor eligibility (an implied attribute), the explicitly stated class, and priority attributes for scheduling.

Parent topic: Controlling Job Selection