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World Community Grid Forums
Category: Support
Forum: BOINC Agent Support
Thread: running multiple cores, multiple processes |
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Thread Status: Active Total posts in this thread: 8
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vanster
Cruncher Joined: Jan 9, 2007 Post Count: 13 Status: Offline Project Badges: 
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I have noticed that in Windows on my quad-core CPU unless I am running 4 WCG jobs simultaneously, my point totals are sometimes only 50% of the estimated points. This seems to be due to the jobs continually switching between cores and all the overhead that eats up. If I allow all 4 cores to work on WCG tasks, they all stay in their particular core, and performance for BOINC goes up ( but my computer is really slow for anything else....) If I lock the jobs to a particular core with the AFFINITY switch ( in Task manager) my point totals do meet or exceed the estimated totals.
But I am able to do this only when each job actually loads into memory to begin execution. Is there a way this option could be written into the BOINC client? |
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sk..
Master Cruncher http://s17.rimg.info/ccb5d62bd3e856cc0d1df9b0ee2f7f6a.gif Joined: Mar 22, 2007 Post Count: 2324 Status: Offline Project Badges: 
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It is undesirable for the apps to use affinity.
It would be so useful if we had a Boinc configuration that allowed us to run on 4 cores when the system was not in use but free up one when we are using the system. In the long run this should be a recommended setting; it’s not like core counts are going to fall. |
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vanster
Cruncher Joined: Jan 9, 2007 Post Count: 13 Status: Offline Project Badges:
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why is it undesirable?
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sk..
Master Cruncher http://s17.rimg.info/ccb5d62bd3e856cc0d1df9b0ee2f7f6a.gif Joined: Mar 22, 2007 Post Count: 2324 Status: Offline Project Badges:
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The CPU is designed to allocate and process according to CPU thread availability; messing with this can lead to a sluggish/unresponsive system and poor task performance in some circumstances.
Thermal stresses on the CPU by running on one core but not the others would shorten the lifespan of some CPUs (when people chose to use say 50% of the CPU). Many CPU’s take core temperature into account when deciding what thread to use, in order to avoid this stress. It would interfere with GPU crunching (reduce performance) and probably lead to task failures. While I have no doubt that it would improve performance for some tasks, I doubt it would improve all task performances at WCG and all other projects, especially when running multiple projects. You might have an excellent heatsink and fan but some would not and this could see their desktop or laptop run too hot or too loud, and they would stop crunching. It would need to be viable for everyone, and non-exclusive. |
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Former Member
Cruncher Joined: May 22, 2018 Post Count: 0 Status: Offline |
The CPU is designed to allocate and process according to CPU thread availability; messing with this can lead to a sluggish/unresponsive system and poor task performance in some circumstances. Thermal stresses on the CPU by running on one core but not the others would shorten the lifespan of some CPUs (when people chose to use say 50% of the CPU). Many CPU’s take core temperature into account when deciding what thread to use, in order to avoid this stress. Isn't that why we have super good cooling for our CPU's and cases??? I have so many fans in my system it tends to hover about 2 feet off the ground.. (I've had to tie ropes to it to keep it from floating all the way to the ceiling because to get it down I have to unplug the system and it makes a terrible crash when it hits the floor!  |
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vanster
Cruncher Joined: Jan 9, 2007 Post Count: 13 Status: Offline Project Badges:
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points taken. I'm running 3 of 4 cores on WCG projects, the last one I leave open for my regular work. I limit the WCG to 90% of core untilization, and halt all WCG processes when the total cpu core reaches 85% utilization. By doing this I limit my core temp to about 51 C. I also manually balance out which core gets the next job so that no core is either under- or over-used.
I admit it's very nerdy, and requires some extra time on my part to keep messing with things but that's just me. I'll probably get tired of messing with everything soon, and just turn all 4 cores back to WCG, and limit the utilization to 80% to keep things from cooking. |
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vanster
Cruncher Joined: Jan 9, 2007 Post Count: 13 Status: Offline Project Badges:
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I have a lot of fans in my system too. I keep my box in a special cabinet built into the desk. That way I don't have to have unsightly ropes laying about. (the wife my get another idea about how to use them...) And this way, the dust in the room is kept moving away from my desk, until it winds up on the other side of the room, covering my drum kit.
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Hypernova
Master Cruncher Audaces Fortuna Juvat ! Vaud - Switzerland Joined: Dec 16, 2008 Post Count: 1908 Status: Offline Project Badges: 
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I have so many fans in my system it tends to hover about 2 feet off the ground.. Loved that.  In my room where I keep my machines there more than 100 fans running. The big majority is 120mm and some are 140mm. It made me wonder if all the fans where to be used together what could I lift. Probably nothing as one single fan does not even lift himself. Maybe if we make it spin at 5'000 rpm   |
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