Drop in WU size?

Message boards : Number crunching : Drop in WU size?

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huangyizhe

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Message 710 - Posted: 20 Jan 2018, 2:56:19 UTC
Last modified: 20 Jan 2018, 3:18:52 UTC

I noticed a recent drop in WU size to about 1/8. Is there any particular reason for that?
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Sergei Chernykh
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Message 711 - Posted: 20 Jan 2018, 8:51:16 UTC - in response to Message 710.  
Last modified: 20 Jan 2018, 8:52:06 UTC

We've had a bunch of very GPU-friendly (highly parallelizable) workunits recently, but as far as I can tell, we're back to regular workunits again. All workunits were calibrated to have approximately the same amount of computations for CPU version.

Run times on GPU are usually stable too, but sometimes they can vary a lot.
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Hotbit

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Message 728 - Posted: 6 Feb 2018, 13:59:28 UTC - in response to Message 711.  

Interesting information.

As WUs are run on GPUs - is it possible to calibrate them for GPUs rather than CPUs?
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Sergei Chernykh
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Message 729 - Posted: 6 Feb 2018, 16:08:10 UTC - in response to Message 728.  

The speed increase for GPU over CPU depends on how well a WU can be parallelized, but it's hard to predict without actually running each WU. It's even different between various GPU models. CPUs are more stable because they don't run that many parallel threads. That's why WUs were normalized for CPUs.
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Message boards : Number crunching : Drop in WU size?


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