PSA: Finite scheduling in MRP always uses one scheduler only

Kinetic ERP
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I have not verified this, but I believe it; Warren in support is pretty sharp.

So, I discovered by accident today that even though I have 7 schedule logs shown below (all with today’s day on them), only one is scheduling. (Just look at the file sizes of the schedule logs.)

Apparently I have had MRP set to do finite scheduling for a while and did not know it. I sure never did that on purpose, but lo and behold, that’s how it was set.

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What’s the big deal? Well, this has been adding over 2 hours to MRP every night and I didn’t even think to look at the schedulers. I just thought it was slower. (Well it is - my BOM copy times shot up by a lot. But that was only half the story.)

I happened to notice that ALL of my processes would be “waiting for part” for 2+ hours each. I have seen 6 of 7 waiting for the one process to finish, but not ALL of them. I was baffled as to why they were waiting if everyone was done with level zero. It’s because they were waiting on the scheduler - not the processes.

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And it’s all because MRP was set to finite scheduling.

Now, if you need finite scheduling then fine. Just know that it will only use one scheduler, no matter what you type in.

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(I’ll have proof tomorrow either way.)

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What is finite scheduling vs not having that checked?

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Yep, I learned the same thing about 9 months ago. Good on you for bringing that knowledge here.

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Finite scheduling (there is a checkbox that enables it on each Resource) means that each operation on that resource will make that resource unavailable to any other job for the length of time it takes to do that job operation.

It only allows you to schedule as many hours per day of activity on that resource as you have hours available in your Production Calendar for that Resource for that day.

As opposed to “infinite scheduling”… where the scheduling engine does NOT take into account that you’ve already scheduled 96 hours of work on that 5-axis machine for today and happily schedules an additional 8-hour operation.

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Awesome, thanks for the concise explanation Ernie!

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Good clarification that I missed. I am told that this will also do the same damage as the MRP checkbox (or benefit if you see it that way…).

I did a BAQ and all of our resources are finite = false.

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So what’s probably happening here (I have no direct knowledge of the actual code base), when you check that box in Process MRP, it sets up the Scheduling Engine SO THAT if any resources are finite, nothing else will interrupt them. In your case, uncheck the box on Process MRP and all will probably be well for you.

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I made the change for tonight (and all future runs). I will report back tomorrow with the results.

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Rocky Horror Anticipation GIFs | Tenor

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Confirmed. MRP ran faster by 2 hours and 10 minutes last night.

EDIT: This is more like it. Some processes wait longer than others, but at least one should have almost no wait time.

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