Unicenter CA-Scheduler Job Management for VSE User Guide

3.9 Defining Jobs
Defining predecessors forces Unicenter CA-Scheduler to witness a specific
event before starting AUTO-STARTed non-CPU jobs or submitting CPU jobs.
Predecessors can be a variety of events:
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The start or end of another schedule or job
The close of an output data set or output generation data group
A user-defined event that you can control using a global parameter
The normal completion of a job that isn't controlled by Unicenter
CA-Scheduler
An event that occurred sometime in the past
Defining predecessors for schedules forces Unicenter CA-Scheduler to witness
a specific event before evaluating any jobs in that schedule. You can also
define predecessors for individual jobs. If both a schedule and its jobs have
predecessors:
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None of the schedule's jobs will be evaluated until the schedule's
predecessors are satisfied and the schedule starts.
Once the schedule's predecessors are met, other factors such as start times
determine whether the job is ready to be submitted once its predecessors
are satisfied.
Note: Defining predecessors for jobs does not override a schedule's
predecessors: instead, predecessors are cumulative.
When jobs must run in a certain order, define predecessors for either schedules
or jobs. Be careful deciding what that predecessor should be: check what days
your predecessor is selected. For example, suppose your job's predecessor isn't
eligible to be selected on the same day your job is. If a predecessor is not in
the day's workload, Unicenter CA-Scheduler ignores it: your job runs without
waiting for the predecessor. This feature makes writing criteria statements
easier. See the chapter "Criteria Language" for instructions on how that is
done.
When Unicenter CA-Scheduler lines up work to be processed during the day,
the first factor it considers is predecessors. Then Unicenter CA-Scheduler
compares start times, putting schedules that can start earliest ahead of ones
that start later. Unicenter CA-Scheduler orders jobs within schedules in the
same way: jobs that can start earlier go ahead of jobs from the same schedule
that have later start times.
Schedules without predecessors and start times go to the top of the list because
nothing is delaying them from starting. Likewise, jobs without predecessors
and start times are the first jobs listed for each schedule.
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