Explicit Loop Vectoring in Job Sequences

[rameshrr3]

If I have an N element loop = say N =14, has anyone tried running 4 loop iterations at a time simultaneously by explicitly coding ( designing ) the Loop activities that way ? If one of the 4 instances breaks- say file not found, will restarting the job sequence kick off all 4 simultaneous iterations or only the one that broke ? I understand it will take some time to build some good exception catchers and controls into such a loop ( Like if we go for 4 way parallel execution - and the total number of list elements is not a multiple of 4 etc , then some loop iterations need to go idle or skip the unwanted iteration etc ) . If CPU utilization is fairly low on average, I don't see this approach having potential to create harm. But your thoughts/feedback are appreciated

Does the Basic JCL(DS) runtime engine actually do this automatically or would it have to be 'coded in'?

Thanks
Ramesh

[ray.wurlod]

The checkpoint mechanism keeps track of the iteration within a loop (skipping unneeded iterations on restart), so I would imagine it properly keeps track of the iteration within each loop when there are more than one.

View the code (on the Job Control tab) to see how this is implemented, or look at the checkpoint entries in the job log.