How the job Moves in Queues

1.

      The  Database  holds the Timetable of when the jobs run. CA-7 periodically scans the databases(timetable)for which jobs are likely to run in the next few minutes .

2.      When the clock strikes 09:00 HRS, the job A enters into the Request Queue. The JCL of the Job is picked up from the JCL  Library and added to the Trailer of the CA-7 Request. Each Job in the Request Queue waits for certain requirements to meet.

3.      When all conditions and requirements are met, the job progresses ahead to the WLB(Workload Balancing).

4.      When there are enough initiators to pick up the Job from the Queue, the job is sent to the JES2. While a job is on WLD or JES2, its shown on the  Ready Queue.

5.      An SMF Type 20 or 30 record(job initialization)is received by CA-7, and the job is moved to the Active Queue, and will start execution in an address space.

6.      The job will remain on the Active Queue, until an SMF Type 5 or 30(job completion) is received by CA-7. On receipt  of the job completion, if the job is successful, the Prior Run Queue(PRRN) Queue will be updated with the details of the execution. This serves as a last run-time record for the job. However,  if the job fails, it will se returned to the Request Queue(REQ).  

 Steps in Normal Queue Flow

1.      Job header record is written to the Request Queue when the job is scheduled to run

2.      When all requirements are satisfied, the header record is sent to the Ready Queue

3.      When CA-7 receives SMF data for the job, the header record is sent to the Active Queue

4.      When the job completes, the header record is sent back to the Request Queue

                         Header record is then sent to the Prior-Run Queue on normal job completion