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World Community Grid Forums
Category: Community
Forum: Hardware Chat Room
Thread: Use 1 out of 2 cores 100% or Use 50% of 2 cores? |
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Thread Status: Active Total posts in this thread: 18
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Former Member
Cruncher Joined: May 22, 2018 Post Count: 0 Status: Offline |
50% of two cores works better for me.i run my fan slightly faster from 2k to 3k on my MacBook pro. I'm able to crunch without raising CPU temp past 50 Celsius.
It really depends on your hardware and what you can measure and control. If you adjust fan speed, you have more options. If you can only see CPU temp, run boinc in different configurations to see when high RPM fan kicks in. They'll you know how to tweak your settings to keep the high RPM fan from kicking in. Fans don't kick in until temps rise so they don't start and stop every second. Half the people responding sound like they Haven't tested this themselves. On my MacBook pro, I run 75/50 with 3k RPM On my 2011 MBP I run 75/33 with 3k (I use for other things besides crunching) My Dell laptop, I run 75/50 with no fan adjustment. Fan kicks in slightly but not max RPM. I also do work on this otherwise, I'd do 75/75 Anytime I run CPU 100% even just one thread, fans always kick in to max RPM. Imo heat seems to generate most when you sustain a thread at 100%. Desktops are more forgiving but laptops hate performance |
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KLiK
Master Cruncher Croatia Joined: Nov 13, 2006 Post Count: 3108 Status: Offline Project Badges: 
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I'd suggest use 50% of CPU time instead of 50% of CPU (cores), from a thermal management.
----------------------------------------Why? If you run 1 CPU on 100%, the other will be cooled down. Too much thermal stress is on one side of CPU, while other is colder -> doing this constantly can't be good for mechanical properties of CPU. So I'd run it on 50% of CPU time, heat both cores equally & then I'm sure there's not a problem. ;) |
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QuantumEthos
Senior Cruncher Joined: Jul 2, 2011 Post Count: 336 Status: Offline Project Badges: 
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use processor lasso https://bitsum.com/howfree/
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katoda
Senior Cruncher Poland Joined: Apr 28, 2007 Post Count: 172 Status: Offline Project Badges:
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If you run 1 CPU on 100%, the other will be cooled down. Too much thermal stress is on one side of CPU, while other is colder -> doing this constantly can't be good for mechanical properties of CPU. Actually it works in a different way - operating system will constantly move such task between cores, ensuring more or less equal load. The scenario you described is possible only if you manually change the affinity of the process from default to a specific core. I have a two-core laptop PC where, due to the temperatures and noise level, I run only one WCG task on 100%. Both cores present equal load while checking them in Process Manager. BTW, in the past there was a project where having WCG running on 50% of CPU time was causing workunits errors. Since then, I'm avoiding using this feature as much as possible and I prefer to limit number of WCG processes, keeping 100% CPU time.  |
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Former Member
Cruncher Joined: May 22, 2018 Post Count: 0 Status: Offline |
I'd suggest use 50% of CPU time instead of 50% of CPU (cores), from a thermal management. It depends on the specific software design, what I mean is in my previous comment I showed how setting up a CPUQuota based on a percentage share of the CPUs, but when systemd absorbs (internalizes?) that value it converts it to milliseconds per thread (kind of - it's quite complex and is controlled via several math functions) which has the desired effect. (of course this is only for Linux) I took a few screenshots from a laptop and the Zabbix monitor(s) for it, which I built using using lm_sensors output combined to see the relevant data on the same scale (fan RPMs/100 to make it "near Celsius range") showing the results. I live in a hot geographic area and the house A/C is set hotter when I'm at work, so there are minor fluctuations in the temperatures - I can watch the laptop get 2-5 degrees C hotter during the daytime sun hours, sometimes bringing the fan RPMs a little higher (it's minimum seems to be 3000 RPM, it doesn't spin slower - just turns off below that) now and again. I tried to set up Imgur to share: https://imgur.com/a/nhqBmfJ This particular laptop is a Dell E6330 w/ i5-3320M running on AC power, nothing special. (edits: fixed typos and stuff) [Edit 3 times, last edit by xithryx at Aug 5, 2018 7:58:37 PM] |
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Aurum
Master Cruncher The Great Basin Joined: Dec 24, 2017 Post Count: 2391 Status: Offline Project Badges: 
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Interesting question, but, summer is killing me too. I have two problems, the hottest summer ever in my town and I have a Time-Of-Use (TOU) electric meter so during peak hours my rate goes up 7x.
----------------------------------------I never change CPU usage for a CPU project like WCG. I do change it for some GPU projects, e.g. Milkyway & Einstein benefit but Asteroids does not. I tell by watching GPU-z %gpu. Asteroids only asks for 0.01 CPU so it's great combined with WCG since it does not take over a CPU. My summer solution is to use BOINC/Options/Computing Preferences/Daily Schedule. My Peak Hours are 13:00 to 18:00 so I set it from 18:00 to 10:00.   ...KRI please cancel all shadow-banning |
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mmonnin
Advanced Cruncher Joined: Jul 20, 2016 Post Count: 148 Status: Offline Project Badges: 
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I would lower the voltage and frequency to achieve a lower power output with both threads running. Often times CPUs can be undervolted and still run at stock speeds.
---------------------------------------- [Edit 1 times, last edit by mmonnin at Aug 6, 2018 7:47:19 PM] |
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hiimebm
Senior Cruncher United States Joined: Oct 19, 2014 Post Count: 305 Status: Offline Project Badges: 
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If a workunit took exactly 1 hour, then:
----------------------------------------100% on 1 core would complete 1 task in an hour 50% on 2 cores would complete 2 tasks every 2 hours. At the same time, a constant load is usually more stable. I left BOINC on by accident one time when I was in GTA V; 2 cores at 100%. My temps were a little higher and my FPS about 5 FPS lower, but other than that I didn't notice anything. (boinc runs at low priority)  |
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