CPU and GPU working together by default

Has something changed? I know it has on my end. I realized that my wife's computer has an onboard 8200 Geforce that isn't being used. I was pleased to see this as CUDA capable.

So, I enabled it in bios, and the 8200 is working (no monitor plugged into it) along with the main GPU 8600 GT. Not in SLI, which is fine. I understand this, forget about SLI, please :)

BOINC starts and doesn't mention the 8600 at all. It says, "CUDA devices found"
Geforce 8200 coprocessor (2).
Hmm, ok, but I know that the 8600 is working too due to video lag and elevated temperature.

But then I noticed something else; on this triple core processor all 3 cores are almost maxed out. So I looked under, "tasks" and there are 4 separate files that are being worked on, as opposed to only 1 at a time last night. The CPU is under almost a full load. What's different?

BOINC starts and doesn't mention the 8600 at all. It says, "CUDA devices found"
Geforce 8200 coprocessor (2).
Hmm, ok, but I know that the 8600 is working too due to video lag and elevated temperature.

The latest client handles multiple GPUs, but not quite correctly:
it picks the fastest one, then acts as if all the GPUs are that kind.

The main problem with this is memory: e.g.,
if the faster board has >= 256MB but the slower board has < 256MB,
BOINC will try to run the SETI@home/CUDA app on the slower board.

We'll fix this at some point, but probably not for a couple of months.

-- David

But then I noticed something else; on this triple core processor all 3 cores are almost maxed out. So I looked under, "tasks" and there are 4 separate files that are being worked on, as opposed to only 1 at a time last night. The CPU is under almost a full load. What's different?

Seeing how you use about 5 CPU minutes per GPU task, that might be it. (The CPU is only used to move data to and from the video card's memory. It looks like it's swapping a lot here).

Well, I'm certainly no expert, but I know the onboard video is using shared system memory, it doesn't have it's own memory. Perhaps that accounts for the swapping.

I haven't done any kind of file alteration. But it appears like both GPU and the CPU is in use. That machine works on 4 tasks at a time now. 2 tasks specify CUDA, the other two do not.

I'll check again to be sure here shortly. Wife is on that box playing world of warcraft right now :(

Hey, also I've added a miniitx system to the mix. It's a wimpy little system with a 1.4ghz Geode processor, but it was just sitting around anyway. Once I get stats on it I want your opinion on whether it's worth the juice to run it forever.

Here we go, analyze this for me;

unmodified GPU and CPU working on S@H?

Thanks for the information there. After those tasks are completed I'll see how it acts afterwords.

The only change I made to that system was enabling the onboard Geforce 8200 graphics for the purpose of more crunching, and those were the results. In any case, I find it's highly efficient to be using that onboard video that was just sitting there disabled, even if the 8200 is relatively slow.

Now having said that, perhaps you can clear something up for me; are some tasks larger/more complex than others? I now have a 1.4Ghz mini itx (no CUDA) running and after 1.5 hours it's at like 30% done on a task. But on my 9800GT CUDA, after an hour I'm only at a few percent. Is this to be expected?

Thanks in advance.

Ah, ok. Much appreciated.

I think part of the problem was that I was using the 9800GT system, and to top it off the task progress is not refreshing in real time because it's dragging down the graphics card so hard that it's like a slide show. Since I last posted the task is close to 50% done now.

For the time being, I'm using the mini itx to surf/post/etc. It's utilizing 100% cpu but is smoking fast in comparison to the Phenom II right now lol in regard to web browsing.

Ok update;

those tasks completed, and it started new CPU tasks. So I'm still getting 2 CUDA related tasks and 2 CPU tasks crunching simultaneously. Before with one CUDA device, it would only do one task at a time. Now with onboard video enabled, it's doing 2 CPU tasks and 2 CUDA.

I don't understand why this is happening when the consensus has been that it can't. I'm glad it's doing it don't get me wrong, but if we can find out why this is happening perhaps we can exploit it for other systems.

I reported one, and the other is finished, and there are 2 more it's working on. So, when I go to report (will hop over and do that now), there will be two reported tasks and two tasks working from CPU to replace them.

edit; ok both cpu tasks completed and reported. It's crunching two more CPU tasks.

Well, I got up this morning and now it's running 3 CPU tasks, and 0 CUDA

:(

I notice that the CPU apps are 6.03, and the CUDA were all 6.08. It's not getting new tasks right now, and the ones it is running are all 6.03. Should I start a new thread? I want to get back on using the video cards. I'm told on 4 machines now when I request tasks that none are available.

It appears there was a change to the scheduler which makes it now possible for CPUs and GPUs to work simultaneously on Seti Enhanced work. So the FAQ is now wrong. I'm still waiting for details on what changed.
____________
Jord

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