36 lines
1.4 KiB
Plaintext
36 lines
1.4 KiB
Plaintext
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1 Each job has a period p and a maximum delay d (<= p)
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At startup we start every job serially
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(potential problem: What if this takes longer than the minimum
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period? We could sort the jobs by p asc)
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Alternatively enqueue every job at t=now
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(potential problem: This may clump the jobs together more than
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necessary)
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In any case:
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If a job just finished and there are runnable jobs, we start the next
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one in the queue.
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At every tick (1/second?) we check whether there are runnable jobs.
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For each runnable job we compute an overdue score «(now - t) / d».
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If the maximum score is >= random.random() we start that job.
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This is actually incorrect. Need to adjust for the ticks. Divide score
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by «d / tick_length»? But if we do that we have no guarantuee that the
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job will be started with at most d delay. We need a function which
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exceeds 1 at this point.
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«score = 1 / (t + d - now)» works. It's a uniform distribution, which is
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probably not ideal. I think I want the CDF to rise steeper at the start.
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But I can adust that later if necessary.
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We reschedule that job.
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at t + p?
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at now + p?
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at x + p where x is computed from the last n start times?
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I think this depends on how we schedule them initially: If we
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started them serially they are probably already well spaced out, so
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t + p is a good choice. If we all scheduled them immediately, it
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isn't. The second probably drifts most. The third seems reasonable
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in all cases.
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