Submit (SU)
The submit (SU) subtask initiates these functions: job submit, job release, started-subtask initiation, and WLM job promotion. When the submit subtask receives a request, for example, to submit a job, it checkpoints the submit sequence-number, loads the corresponding JCL in a storage buffer, and submits this to the internal reader. If the submit is successful, a submit event (type IJ1, IJ2, IJ3, IWTO, IREL, or IWLM) is built, and a subsystem request is issued to broadcast the event-creation routine. If there is no more work for the submit subtask to process, a WAIT is entered.
The submittor task is part of the tracker, but job submission is initiated by the workstation analyzer (WA) task of the controller. Checkpointing of submission requests is the means by which the two tasks cooperate to ensure that all requests for submission are honored.
When the connection between the controller and a tracker is initially established, and subsequently each time the connection is reestablished after some disruption, the controller requests synchronization. A synch request is sent for each workstation defined with a destination of the particular tracker to synchronize submit requests, as some requests might have been lost because of a bad connection or tracker outage. The tracker responds to the request by issuing a synchronization response event, which is written to the event data and communicated to the controller in the same way as other job-tracking events. The event is prefixed IJ0 (see Data areas for control block mapping) and contains checkpoint information that describes the number of submit events processed by the tracker. When the controller reads the synchronization response event, a check is made to determine the number of submit requests that should have been processed by the tracker. If there is a discrepancy, the controller resends the submit request.
Operations that have been rerouted to an alternate workstation will not be resubmitted.
If the tracker, during normal processing, receives a submit request out of order, the request is discarded, and an out-of-sequence synchronization event is created. Upon receipt of this event, the controller immediately suspends job submission for new operations and resends all requests for the reportedly lost job submission request and all following requests. The lost submit-event record is also prefixed IJ0.