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BarryAZ

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Message 42755 - Posted: 11 Oct 2010, 16:04:02 UTC

In the early days, MW was a CPU project (no one was doing GPU work in BOINC land). Then some folks developed ATI GPU applications with worked for a small subset of ATI GPU's (double precision only). The the project integrated that work and application into its 'regular' application set. Then additional work yielded support for a small subset of CUDA GPU's (double precision only).

Around that time there was a lot of discussion (and argument) about splitting the project into GPU and CPU venues to protect work flow. Eventually that discussion ended and we still have a single venue.

However, with the current batch of CPU workunits, it seems that essentially the GPU dominance is in full force.

Over the years I've added 4770 and 4850 GPU's into the mix and these were doing MW GPU work along side my CPU work. With the latest 'oopsies' running loose on but the .20 and .40 (.04) CPU units that, I've gone to hold mode or simply detatched those workstations that don't have the requisite GPU to do GPU work for MW.

I see that Travis is aware that the current CPU work has issues -- I'm hoping to see some confirmation from others that CPU work units are again a productive use of CPU cycles. When that happens, I'm likely to rejoin those workstations (which are doing GPU work for Collatz, Dnetc, and to a lesser degree Einstein and SETI), to the CPU stack of MW.


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Message 42757 - Posted: 11 Oct 2010, 16:59:07 UTC - in response to Message 42755.  

The N-body is currently CPU only. The other application is both CPU and GPU, with GPUs doing most of the work.
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BarryAZ

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Message 42765 - Posted: 11 Oct 2010, 19:32:34 UTC - in response to Message 42757.  

Yes, I realize this -- also, the N-body is going thru various development teething problems (most of which have been acknowledged). Since the other application is GPU, the problems with the N-body application don't affect the GPU side of the project (yet). At this juncture, I'm electing to wait until the new application is a bit cleaner than it currently is. I suspect once that stage has been reached, some brilliant souls will then work on optimizations for the CPU side. I also expect that once the N-body CPU application is troublefree, project folks will work on making it work for GPU's as well.


The N-body is currently CPU only. The other application is both CPU and GPU, with GPUs doing most of the work.


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Message 42768 - Posted: 11 Oct 2010, 23:44:29 UTC

Yes, I'd much like to see the MW@H 0.31 app have its kinks worked out...the GPU version seems to run smoothly from what I've heard (though I can't do it myself), but the CPU version that I run gives estimates of 260 hours to completion, runs for two hours, and reports being at 0.000% completion although running alone and at high priority.

No problems with the N-Body app, actually. Takes maybe 2-4 hours for the average WU to complete, and I never get computation errors. PrimeGrid and Collatz in CUDA, however...can't say they really work for me.

So, what exactly is wrong (developmentally? integrally?) with the N-Body Simulation app?
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BarryAZ

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Message 42769 - Posted: 12 Oct 2010, 0:04:09 UTC - in response to Message 42768.  

Prime Grid for me has been pretty GOU wasteful, too many computational errors after running for hours. No problems to speak of with Collatz and either ATI or CUDA GPU's.

As to MW, I've seen computation errors as well as 'endless workunits' with say three or more hours and 0%. I kill those off. I've seen those problems with the .20 as well as the .04 (.40) applications. So my approach for now is to consign MW processing pretty much to my ATI 4770 and 4850 GPU's. Aqua and Einstein are picking up the CPU cycles.


No problems with the N-Body app, actually. Takes maybe 2-4 hours for the average WU to complete, and I never get computation errors. PrimeGrid and Collatz in CUDA, however...can't say they really work for me.

So, what exactly is wrong (developmentally? integrally?) with the N-Body Simulation app?


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Message 42771 - Posted: 12 Oct 2010, 2:07:59 UTC
Last modified: 12 Oct 2010, 2:09:41 UTC

Just so you know, running the ATI GPU app is no walk in the park, either. The validator fails, and I am forever seeing this message:

10/11/2010 1:40:02 AM Milkyway@home Reporting 4 completed tasks, requesting new tasks for GPU
10/11/2010 1:40:03 AM Milkyway@home Scheduler request completed: got 0 new tasks
10/11/2010 1:40:03 AM Milkyway@home Message from server: No work sent
10/11/2010 1:40:03 AM Milkyway@home Message from server: Your app_info.xml file doesn't have a version of MilkyWay@Home N-Body Simulation.


Would be nice if they could work out a few of the bugs in the current apps before putting out new apps and features (screensaver).
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BarryAZ

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Message 42777 - Posted: 12 Oct 2010, 6:22:58 UTC - in response to Message 42771.  

I agree with you regarding clean current before going to new. But that is much the way of the BOINC world. Look at the BOINC client history.


I've not seen the same problems with the ATI GPU app -- perhaps because I am not looking closely (the work units complete quickly enough). As to not getting new work, well, since none of my 4770/4850 workstations have only one GPU project to support, if MW is recalcitrant, either Dnetc or Collatz gets happy.



Just so you know, running the ATI GPU app is no walk in the park, either. The validator fails, and I am forever seeing this message:

10/11/2010 1:40:02 AM Milkyway@home Reporting 4 completed tasks, requesting new tasks for GPU
10/11/2010 1:40:03 AM Milkyway@home Scheduler request completed: got 0 new tasks
10/11/2010 1:40:03 AM Milkyway@home Message from server: No work sent
10/11/2010 1:40:03 AM Milkyway@home Message from server: Your app_info.xml file doesn't have a version of MilkyWay@Home N-Body Simulation.


Would be nice if they could work out a few of the bugs in the current apps before putting out new apps and features (screensaver).


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Message 42778 - Posted: 12 Oct 2010, 10:52:45 UTC - in response to Message 42771.  

Just so you know, running the ATI GPU app is no walk in the park, either. The validator fails, and I am forever seeing this message:

10/11/2010 1:40:02 AM Milkyway@home Reporting 4 completed tasks, requesting new tasks for GPU
10/11/2010 1:40:03 AM Milkyway@home Scheduler request completed: got 0 new tasks
10/11/2010 1:40:03 AM Milkyway@home Message from server: No work sent
10/11/2010 1:40:03 AM Milkyway@home Message from server: Your app_info.xml file doesn't have a version of MilkyWay@Home N-Body Simulation.


Would be nice if they could work out a few of the bugs in the current apps before putting out new apps and features (screensaver).


I'm not really shure what you mean.
If you want to run the n-body's as well, you need to add some lines of information to your app_info.xml (already posted in some other threads) and download the app from the /download section. After restarting boinc you should get the n-body's.
If you do not want to run them you need to uncheck 'Use CPU' in your personal settings.
This should solve your problems.

Alexander
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Message 42789 - Posted: 12 Oct 2010, 17:35:39 UTC - in response to Message 42778.  

I'm not really shure what you mean.
If you want to run the n-body's as well, you need to add some lines of information to your app_info.xml (already posted in some other threads) and download the app from the /download section. After restarting boinc you should get the n-body's.
If you do not want to run them you need to uncheck 'Use CPU' in your personal settings.
This should solve your problems.

Alexander


Yep, you missed the entire point of the post.
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Message 42794 - Posted: 12 Oct 2010, 19:01:21 UTC

Erm. Ok. So, I've killed the "endless WUs" such as BarryAZ mentioned...now I'm running a few with the .04 app, and while they initially show an estimated time of 10-12 hours, that goes down by about a minute every CPU second, until it ends up finishing in about 4 hours. No validation errors either.

Could be my relatively unmodified machine - the other computer listed on my account here runs a version of XP so heavily modded that getting tasks to download at all, for any project, is a bit too roundabout and unreliable...

Anyhow, I run the n-body WUs without having downloaded anything or editing any xml configs...
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Message 42798 - Posted: 12 Oct 2010, 22:35:03 UTC - in response to Message 42778.  



I'm not really shure what you mean.
If you want to run the n-body's as well, you need to add some lines of information to your app_info.xml (already posted in some other threads) and download the app from the /download section. After restarting boinc you should get the n-body's.
If you do not want to run them you need to uncheck 'Use CPU' in your personal settings.
This should solve your problems.

Alexander


I have use CPU unchecked, but still get the message. The real problem is that the regular validator keeps crashing and then the only work that is being made is the Nbody WU. When those are the only ones available we see the message about no app for them.
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Message 43241 - Posted: 29 Oct 2010, 9:24:53 UTC

I'm new in this project so sorry if I just didn't find correct answer elsewhere. I've already read Boinc FAQ but didn't manage to find the way to force Boinc client to use only GPU for one project(say, MW) and only CPU for another project.
Thank you in advance.
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Message 43243 - Posted: 29 Oct 2010, 9:36:48 UTC - in response to Message 43241.  

I'm new in this project so sorry if I just didn't find correct answer elsewhere. I've already read Boinc FAQ but didn't manage to find the way to force Boinc client to use only GPU for one project(say, MW) and only CPU for another project.
Thank you in advance.

Go to your account for each respective project and change your preferences to suit what you want to happen for that project.
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