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Levent TERLEMEZ

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Message 48734 - Posted: 13 May 2011, 10:31:25 UTC

crunching milkyway wus? I have an AMD Phenom II X4 and milkyway uses all of the cores. But there are other projects running in the list, so I want them be running too. Looked at the configs in my account but there is nothing like this. Thanks for the tips.
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Matt Arsenault
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Message 48736 - Posted: 13 May 2011, 14:30:23 UTC - in response to Message 48734.  

crunching milkyway wus? I have an AMD Phenom II X4 and milkyway uses all of the cores. But there are other projects running in the list, so I want them be running too. Looked at the configs in my account but there is nothing like this. Thanks for the tips.
See here: http://milkyway.cs.rpi.edu/milkyway/forum_thread.php?id=2403&nowrap=true#48735 However you can use app_info.xml to set the number of threads manually, by adding something like this:
<avg_ncpus>2</avg_ncpus>
    <max_ncpus>2</max_ncpus>
    <cmdline>--nthreads 2</cmdline>
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Profile Chris Skull
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Message 48760 - Posted: 14 May 2011, 7:47:41 UTC

I think Levent means the project weight.
You can set the project weight in each projects preferences. Default is 100.
If you run 3 projects on your quadcore... set MW to 200 and the other two leave 100. Now MW uses 2 cores and the other two projects each one core....
If you change things like this... can take some time before it works correctly... give Boinc manager some time.


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ExtraTerrestrial Apes
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Message 48777 - Posted: 15 May 2011, 10:45:01 UTC - in response to Message 48760.  
Last modified: 15 May 2011, 10:45:54 UTC

No, that will not give him what he's asking for. MW n-body would still take all 4 cores, if it runs. However, the Boinc manager should average project times out according to ressource share - so this [ressource share] is indeed what he should set.

MrS
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elliotts

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Message 48826 - Posted: 17 May 2011, 2:43:09 UTC

I think my issue is the essentially the same, so I will post it here.
Moderator - please move if I posted in the wrong place.

I have an i7 processor. When I receive multi-threaded tasks from milkyway, instead of my system all 8 cores at 100%, the processor utilization bounces around between 30-60% for all cores.

If I suspend all other processing and let the milkyway task have the entire processor, the task completes in about 8 minutes.

If I just let it run, without suspending the other tasks, the milkyway task takes hours to complete; and virtually nothing else is processed. Likely more time is spent swapping out tasks than actually crunching numbers...

It would be nice if I could set something to let the milkyway task take over the system when the application switch occurs. Then it could run to completion, after which the other tasks in the queue would run normally.

Are there any project setting that control how multi-threaded applications interact with single-threaded apps that would help me? I was told the BOINC client does not have anything in this regard...

TIA for any assistance,
Tom
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Message 48835 - Posted: 17 May 2011, 14:02:02 UTC - in response to Message 48826.  

Elliotts,
Just go with the same solution that Matt posted. Limit MW tasks to at most 4 processors on your i7 (odd numbers are also valid). I've set BOINC & MW to only use 4 CPUs, and MW tasks finish in 8 minutes.
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Levent TERLEMEZ

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Message 49159 - Posted: 7 Jun 2011, 7:23:42 UTC

Thanks for the advices and information. Have a nice day.
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