My question is whether I should separate the server into two processes, one to manage updates/assignments and the other to spawn the processes for each job on time. I need to make sure that the processes are spawned as near to the scheduled time as possible (within seconds).

Seems pretty obvious to me that there must be two processes, since you don't want any of the two parts hog each other: one looking at the hourglass and pushing buttons, and another looking for requests for jobs to pass to the button pusher. If not stressed, the button pusher will incorporate that request paper into his TODO list.

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