High CPU usage on GPU tasks

Skivelitis2
Skivelitis2
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Topic 215634

Work units: 359122192 and 359051144 (others in progress)

 Why is my CPU time almost equal to my GPU time on these work units? Wingmen show more along the lines of what I would expect. Do I need a settings tweak somewhere?

 

                  

Logforme
Logforme
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Are you comparing Nvidia

Are you comparing Nvidia cards against AMD cards?

The Nvidia tasks use a lot of CPU. If I remember correctly it's something in the Nvidia driver causing the CPU to loop while waiting for the GPU instead of sleeping.

Skivelitis2
Skivelitis2
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Looks like that is exactly

Looks like that is exactly it. Using driver provided in synaptic on Linux (Mint 18.3). Is there an updated version anyone is aware of that solves the problem?

mmonnin
mmonnin
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Yes, OpenCL has high CPU

Yes, OpenCL has high CPU usage on NV cards. 

Skivelitis2
Skivelitis2
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mmonnin wrote:Yes, OpenCL has

mmonnin wrote:
Yes, OpenCL has high CPU usage on NV cards. 

 

Thanks, I'll wait for some CUDA work then.

Logforme
Logforme
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Skivelitis2 wrote:I'll wait

Skivelitis2 wrote:
I'll wait for some CUDA work then.

I know crunchers have requested CUDA versions of the GPU app(s). Can't remember what the project staff have said. But I can imagine it would be a pain to develop and maintain 2 versions of the apps, multiplied by platforms (Win, Linux, Mac).

Best thing would of course be if Nvidia put some effort into their OpenCL driver. But I don't see that happen anytime soon. Why compete with themselves (CUDA)?

Skivelitis2
Skivelitis2
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Logforme wrote:Skivelitis2

Logforme wrote:
Skivelitis2 wrote:
I'll wait for some CUDA work then.

I know crunchers have requested CUDA versions of the GPU app(s). Can't remember what the project staff have said. But I can imagine it would be a pain to develop and maintain 2 versions of the apps, multiplied by platforms (Win, Linux, Mac).

Best thing would of course be if Nvidia put some effort into their OpenCL driver. But I don't see that happen anytime soon. Why compete with themselves (CUDA)?

I thought the Arecibo GPU app was CUDA. I better check the applications page again......:(

archae86
archae86
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Logforme wrote:... CUDA

Logforme wrote:
... CUDA versions of the GPU app(s). Can't remember what the project staff have said.

Months ago I think one of the project people suggested that they were likely to make a trial build with CUDA when they had time, and that if it worked well would use it.

I'm sure this ranks in priority below keeping up with the science, keeping the user hunger fed, and obeying the law, among other things.

Even if they try it, there is no assurance it will work, nor that it will be better in the ways we hope.  Still, you can count me among the many who hope that a CUDA version comes out, as that seems the most likely way forward for efficient processing with using the polling loop communication method that seems responsible for keeping our CPUs busy doing almost nothing.  Such a build might also make more efficient use of the GPU, possibly giving us output increase on given hardware.

Skivelitis2
Skivelitis2
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I only have Nvidia GPUs and

I only have Nvidia GPUs and just can't accept that type of "ovehead' for a non badge granting project.

Will make an exception for the Pentathlon event only. Such a pity.

Betreger
Betreger
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I don't need a stinking

I don't need a stinking badge, all I want to do is find a pulsar or gravity wave.

Skivelitis2
Skivelitis2
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Posts: 11
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I need lots of stinking

I need lots of stinking badges.Laughing For me, they provide nice, short term goals to help alleviate the monotony of long term crunching. But to each his/her own.

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