Deadline scheduling

Deadline scheduling ensures that a job is submitted at a specified priority level, allowing JES3 to schedule it while making best use of the available system resources. If the job is not scheduled on time, the priority level of the job is increased to ensure that the job is processed before its specified deadline.

Deadline scheduling is specified for a job using the DEADLINE subparameter on the //*MAIN control statement in the job stream. With this parameter, the programmer specifies the actual time the job is due to be scheduled. When input service recognizes the DEADLINE parameter, it places the entry into a special deadline queue and internally calls the DEADLINE DSP to control the job. You can use the *INQUIRY,A,D=DEADLINE command to display the status of the job currently being processed by the DEADLINE DSP. You can use the *INQUIRY,A,D=DLINE command to display the status of all jobs on the deadline queue. Deadline specifications are determined during JES3 initialization on the DEADLINE statement.

Normally, deadline scheduling requires no operator action; however, operator commands are provided for you to handle special situations. You can use the *INQUIRY,L command to display the deadline specifications and the *MODIFY,L command to alter them. If you need to alter deadline specifications, then you must enter the *START,L command after the *MODIFY,L command.