cpu vs gpu jobs preference

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sk69
Posts: 27
Joined: Sun Apr 05, 2020 6:41 pm

cpu vs gpu jobs preference

Post by sk69 »

Hi,
Is there anything I loose in terms of points, bonus calculation, type of projects being allotted if I choose to run only CPU vs only GPU client?

The reason i ask is that when both my CPU and GPU slots are running, then my laptop hits 80 degree c in both gpu and cpu. If i run only one of those slots at a time(either cpu or gpu), then the temperature hover around 60 degree only! Huge temperature difference. Hence, I was wondering i can just remain one slot paused, and let the other run. Ofcource I understand that by not running one slot, I do not earn those extra points, but is there any other consideration?
ajm
Posts: 754
Joined: Sat Mar 21, 2020 5:22 am
Location: Lucerne, Switzerland

Re: cpu vs gpu jobs preference

Post by ajm »

You can do that.
You also can allocate less threads of the CPU (in Advanced Control -> Configure -> Slots -> clic "CPU" then Edit -> enter the number of threads (half of total for example, and it should be a multiple of 2 and/or 3) -> OK -> Save.
And you can throttle your CPU. In Windows, you can adapt the Power management. Or you can do that in the Bios.0
For the GPU, the driver software should allow that, too.
Joe_H
Site Admin
Posts: 7870
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MacBook Pro 2.9 i7 8 GB smp2
Location: W. MA

Re: cpu vs gpu jobs preference

Post by Joe_H »

Run in a manner that you are comfortable with. One CPU slot or one GPU slot is fine. We could ask that you set any WU to Finish on the slot you are going to not use. That way you don't have any assigned WUs not returned which can matter in the short term when determining eligibility for the bonus.

If you never want to use the slot, then you can delete it. Or set it to 'pause-on-start' 'true' in FAHControl so that it only starts when you want it to.
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iceman1992
Posts: 527
Joined: Fri Mar 23, 2012 5:16 pm

Re: cpu vs gpu jobs preference

Post by iceman1992 »

It depends on your specific laptop, of course. I suggest you run a few WUs CPU-only, and then run a few WUs GPU-only, then compare the PPD for both.
As Joe_H mentioned above do make sure to complete all pending WUs when you switch slots.
I would even say there's a chance that CPU+GPU would not make a big difference to just GPU or just CPU, because of possible thermal throttling when both are under heavy load.
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