Letting cuda WUs use a full thread/core

FrankHagen
FrankHagen
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RE: Why would it need a

Quote:
Why would it need a full cpu core to run a unit being crunched by the gpu?

interesting question!

if you run the linux app with 270.xx drivers which uses a whole CPU-core for a cuda task, you probably get it.

afaik - and this is only oberservation whithout having a chance to get hands on the source-code - it's pretty obvious to me. a lot of cpu activity needed to feed the gpu. and latency on HT-cores does not help...

Dirk
Dirk
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I decided to make a graph

I decided to make a graph anyway :P

Here it is, the numers in red show the amount of CPU tasks running along with 4 GPU tasks. The CPU tasks are from a couple different projects, ibercivis, malariacontrol and climateprediction atm, though I switch around to other CPU projects whenever I feel like it. Not running any einstein CPU tasks atm because my GPU is already doing plenty of work for it.

Note that the CPU is running at 3.10 GHz (2.93 is stock) and that turbo boost is turned off. I'm also browsing internet, listening to music and/or watching videos while it crunches.

The drops in the beginning are caused by me manually starting more cuda tasks.

FrankHagen
FrankHagen
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RE: I decided to make a

Quote:

I decided to make a graph anyway :P

Here it is, the numers in red show the amount of CPU tasks running along with 4 GPU tasks.

if you are really into it:

install ubuntu 11.04 using WUBI

http://www.ubuntu.com/download/ubuntu/windows-installer

and see what happens then..

Dagorath
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RE: I have multiple

Quote:
I have multiple machines with multiple cpu's and even one machine with 2 gpu's in it, all the gpu's and ALL the cpu's crunch 100% of the time on their own workunits.

OK, Mikey, so your GPUs are crunching all the time. That's a totally different concept than having your GPUs being utilized to 100% of their capacity when they're crunching. Have you checked your GPUs to see how much of their capacity is being utilized when they're crunching? Sorry, I don't know how to check that on Windows, just Linux.

@ Dirk,

Hmmm. You may be onto something with that Binary Radio Pulsar Search v1.08 (BRP3cuda32fullCPU) application for Linux. Myself I would be a little skeptical and not jump to the conclusion that it drives the GPU so hard it needs a full CPU to service it just because it has "fullCPU" in the name. I'll wait until the project devs comment on that. If what you're thinking IS true then hopefully there will soon be such an app for Windows too. Or maybe not. I think you've found the perfect excuse to install Linux in a dual-boot configuration which allows you to boot either Linux or Windows depending on your mood/needs that day. You say you like tinkering now trust me there is enough tinkering in Linux to last a good tinkerer a lifetime. Just think... you could have that BRP3cuda32fullCPU app to play with NOW rather than later ;)

Dirk
Dirk
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RE: RE: I decided to make

Quote:
Quote:

I decided to make a graph anyway :P

Here it is, the numers in red show the amount of CPU tasks running along with 4 GPU tasks.

if you are really into it:

install ubuntu 11.04 using WUBI

http://www.ubuntu.com/download/ubuntu/windows-installer

and see what happens then..

Tempting, I may try that soonish. Gonna be installing a new CPU cooler when it arrives and then tinkering with some CPU overclocking first though. I'd need to make it a dual boot because I also use this pc for gaming, studying, work etc. For that win7 works great and I'm very used to it.

FrankHagen
FrankHagen
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RE: Tempting, I may try

Quote:
Tempting, I may try that soonish. Gonna be installing a new CPU cooler when it arrives and then tinkering with some CPU overclocking first though. I'd need to make it a dual boot because I also use this pc for gaming, studying, work etc.

dual boot is exactly the idea behind it.

i know the cuda jobs run a lot faster on my GTX260 and the GTS250, but for you it may be just a "where no mankind has gone before" job.. ;)

anyway: HTH if you need!!

telegd
telegd
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I don't remember the exact

I don't remember the exact numbers, but the Linux fullCPU CUDA apps ran a bit faster on my modest machine than the current 0.2 CPU apps. However, I think the fact that I get one of my CPU cores back for other purposes makes up for the slight speed penalty.

I think the older 260 drivers for Linux will trigger the project to send you fullCPU apps.

mikey
mikey
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RE: RE: I have multiple

Quote:
Quote:
I have multiple machines with multiple cpu's and even one machine with 2 gpu's in it, all the gpu's and ALL the cpu's crunch 100% of the time on their own workunits.

OK, Mikey, so your GPUs are crunching all the time. That's a totally different concept than having your GPUs being utilized to 100% of their capacity when they're crunching. Have you checked your GPUs to see how much of their capacity is being utilized when they're crunching? Sorry, I don't know how to check that on Windows, just Linux.

According to Boinc I am using 0.01 of the cpu and 1.00 of the gpu for my ATI gpu's and 0.08 of the cpu and 1.00 of the gpu on my Nvidia gpu's. This is listed in the Tasks tab of Boinc.

Dirk
Dirk
Joined: 4 Jun 08
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RE: RE: RE: I have

Quote:
Quote:
Quote:
I have multiple machines with multiple cpu's and even one machine with 2 gpu's in it, all the gpu's and ALL the cpu's crunch 100% of the time on their own workunits.

OK, Mikey, so your GPUs are crunching all the time. That's a totally different concept than having your GPUs being utilized to 100% of their capacity when they're crunching. Have you checked your GPUs to see how much of their capacity is being utilized when they're crunching? Sorry, I don't know how to check that on Windows, just Linux.

According to Boinc I am using 0.01 of the cpu and 1.00 of the gpu for my ATI gpu's and 0.08 of the cpu and 1.00 of the gpu on my Nvidia gpu's. This is listed in the Tasks tab of Boinc.

That's just cosmetic though and used by boinc to figure out how many CPU tasks it can run in accordance with your settings. You should check the actual cpu usage of the tasks, I don't know how CPU hungry the ati apps are but cuda apps do need to be fed constantly by the CPU. If I let boinc crunch 8 cpu tasks along with cuda tasks there's a huge battle for cpu time and all running apps lose, this problem is less pronounced when running multithreaded apps like for AQUA (though their ROQS app causes a nice regular pattern of GPU usage drops, kind of looks like a heartbeat).

Anyways, when I install ubuntu will a new boinc install interfere with the windows install? I'm planning on giving them a separate location, both for the boinc folder and the boinc data folder. Maybe I'll even let linux boinc use my ssd for storage.

Also, are there any nice programs for monitoring my GPU for linux as well as my CPU temps?

FrankHagen
FrankHagen
Joined: 13 Feb 08
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RE: You should check the

Quote:
You should check the actual cpu usage of the tasks, I don't know how CPU hungry the ati apps are but cuda apps do need to be fed constantly by the CPU.

this has absolutely nothing to do with cuda or stream or opencl. it's just about how much work the cpu has to do to feed the gpu. or in other words, how much of the total work can be done on the GPU.

Quote:
Anyways, when I install ubuntu will a new boinc install interfere with the windows install?
I'm planning on giving them a separate location, both for the boinc folder and the boinc data folder. Maybe I'll even let linux boinc use my ssd for storage.

no problem. linux will have it's own partition - in case you use WUBI it's simply a virtual one.

Quote:
Also, are there any nice programs for monitoring my GPU for linux as well as my CPU temps?

sorry - no..

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