Processing cyclic jobs has special considerations of which you should be aware if you plan to take advantage of this powerful facility. The following discussion provides detailed explanations of these special considerations.
When a cyclic job is demanded into the tracking file after its early start time has passed, the CA NSM JM Option adjusts for this situation by doing the following:
For example, if the job has an early start time of 1:00 p.m. and a frequency of 60 minutes, and the job is demanded at 3:15 p.m., the CA NSM JM Option generates entry one to start at 1:00 p.m. When the job enters the current workload (by entering the tracking file), the CA NSM JM Option recognizes that it is late (it should have started at 1:00 p.m.) and starts it immediately. The next submitted instance of this job has a start time of 4:00 p.m. with subsequent entries to start at 5:00 p.m., 6:00 p.m., and so forth.
By default, when a cyclic job is brought in late (demanded), the CA NSM JM Option skips the jobs that are too late to run and only runs the number of iterations left, based on the calculation of when the jobs should have run. If you set the Windows configuration setting "cycle count precedence" or the CAISCHD0540 environment variable on UNIX/Linux to Y, the cycle count takes precedence over the remaining count based on current time. Thus, the defined number of cyclic jobs is scheduled up to the time of the new-day autoscan.
Using the default, consider, for example, a cyclic job that has a frequency of 30, a cycle count of 16, and an early start time that defaults to the new‑day autoscan time of 1:00 a.m. The job is typically brought in at 1:00 a.m. and runs 16 times: at 1:00 a.m., 1:30 a.m., 2:00 a.m., and so forth until the last (sixteenth) run at 8:30 a.m. However, if the job is demanded in at 4:05 a.m., the occurrences up to that time are skipped and the job is run at 4:05 a.m., 4:30 a.m., 5:00 a.m., 5:30 a.m., and so forth. At 8:30 a.m., the job runs for the last time, for a total of 10 runs. The occurrences that would have run (at 1:00 a.m., 1:30 a.m., 2:00 a.m., 2:30 a.m., 3:00 a.m., 3:30 a.m.), are skipped. The CA NSM JM Option does not attempt to “catch up” if it means running the jobs after the last calculated start time of 8:30 a.m.
If you enable cycle count precedence using the above example, the jobs would run at 4:05 a.m., 5:00 a.m., 5:30 a.m., and so forth, until the last (16th) ran at 12:30 p.m. All counts up to the time of the new-day autoscan are scheduled.
If you elect to run with the autoscan process disabled, cyclic jobs are submitted only when you execute a manual autoscan. The jobs are not automatically submitted each day. For an explanation of the autoscan process, see Autoscan.
You cannot define a cyclic job as a predecessor to itself. In other words, when a cyclic job is submitted, the job begins execution when its early start time is reached. It does not wait for any preceding instances of itself to complete.
You can define a cyclic job as a predecessor to another job or jobset. All occurrences of the cyclic job are treated as predecessors and must complete before the successor job or jobset is eligible to run.
The predecessor criteria for cyclic jobs include a qualifier option that allows cyclic jobs to run in one of two ways. For example, assume you have two cyclic jobs, CycJobA and CycJobB, where both have an iteration number of 3, frequency is set to 60, and CycJobA is the predecessor of CycJobB. When both jobs are demanded into the tracking file, the file appears as follows:
CycJobA QUAL=xx01 CycJobA QUAL=xx02 CycJobA QUAL=xx03 CycJobB QUAL=xx01 CycJobB QUAL=xx02 CycJobB QUAL=xx03
If you set the qualifier Use Qualifier Predecessor Criteria for cyclic job? to N, CycJobB runs after all CycJobA iterations have run.
If you set the qualifier to Y, CycJobB QUAL=xx01 runs after CycJobA QUAL=xx01 completes, CycJobB QUAL=xx02 runs after CycJobA QUAL=xx02 completes, and so forth.
If you plan to use cyclic job submission for Windows platforms, review the environment settings for the CA NSM JM Option in the Configuration Settings window (Options tab) for Max active jobs, Max resources, Max predecessors, and Use Qualifier Predecessor Criteria for cyclic job? and set the appropriate values to accommodate the additional jobs in the daily workload.
If you plan to use cyclic job submission for UNIX/Linux platforms, review the values set for the environment variables CAISCHD0025, CAISCHD0026, CAISCHD0027, and CAISCHD0040 and set appropriate values to accommodate the additional jobs in the daily workload.
For procedures to identify work to perform, see Defining Jobs in the online CA Procedures.
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