Unicenter CA-Scheduler Job Management for VSE User Guide

6.2 Pitfalls
predecessor criteria of JOB5 to now also require JOB4. If JOB5 had not yet
started, when it is evaluated to start, it will require JOB4, but JOB4 was never
selected. Therefore, JOB5 will never be submitted. It will always be awaiting
JOB4. If this happens, we recommend that you CANCEL and PURGE JOB4
and then issue an ADD command for JOB4.
Pitfall:
When changing predecessor criteria on the database for jobs
that are selected and are already on the tracking file, be aware
that the jobs on the tracking file will be evaluated based on
the most current data on the database. Do not change the
criteria of active jobs.
6.2.4 Backlogging Over Two Autoscans
The subject of backlog is covered in the topic Backlogged Work in the chapter
"Techniques." When a schedule gets backlogged (autoscan occurred before the
schedule completed) due to the first autoscan occurring, it is handled as you
would expect. If, however, it does not finish before the next autoscan (meaning
it has been in the system for 48 hours), when it does finish, the new schedule
that is loaded is evaluated for the autoscan day on which it is loaded which
means that if a schedule that is selected on both Monday and Tuesday and has
its Monday's version backlogged until Wednesday; Tuesday's version will
never be run. That is because the evaluation takes place when Monday's
schedule completes, which is Wednesday, but it does not run on Wednesday.
Always watch backlogged work carefully.
Pitfall:
Backlogged work that goes beyond a 48-hour period can be
lost if not monitored carefully.
6.2.5 Resetting Global Parameters
Global parameters are initialized only when the tracking file is initialized. They
are not reset at autoscan time. Once a value of a global parameter is set, it is
only reset when someone actually changes its value to something else. That is,
predecessor evaluation of schedules and jobs takes place based upon the
current value of the global parameter regardless of when that value is set.
If the preceding is not the way in which you desire to operate, you could have
a batch job that is submitted at a specific time (say immediately following
autoscan) that executes the Unicenter CA-Scheduler program CAJUCMD0 and
supplies transactions that set the global variables to the values you want.
Therefore, the pitfall:
Pitfall:
A global parameter only gets set. If you want it reset, you
must set it to another value. There is no such thing as
resetting a global parameter.
Once a global parameter is set to a specific value, all unsatisfied predecessors
are reevaluated. If any schedules or jobs are waiting for that global parameter
to take on that value, those global predecessors are marked as satisfied.
Chapter 6. Tips 6-21