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CPU usage: Should I allow all threads (100% CPU Usage), or only number of cores (50% CPU in settings)?

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rcollins0618

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Message 77297 - Posted: 21 Dec 2024, 20:59:52 UTC

I've seen "Milkyway@home N-Body Simulation with Orbit Fitting 1.87 (mt)" tasks complete in about 3 minutes (16 cores) or less sometimes. Now that I have all 32 threads running (AMD Ryzen 9 7950X3D), I have two 16 CPU tasks taking over an hour going at the same time. Is this a problem? Or do I just have new tasks that take longer normally?

I just switched back to using 50% CPU in settings to allow one task of 16 CPUs going, not two.

I'll watch and see how long tasks take at 50%.

What's the normal amount of time these tasks take, or do they vary?

Thanks,
Rich
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rcollins0618

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Message 77298 - Posted: 21 Dec 2024, 21:54:08 UTC - in response to Message 77297.  

Edit: It looks like I just switched at a time when processes take 50+ minutes for me to run. I've got one M@H N-Body Simulation with Orbit Fitting 1.87 (mt) [16 CPUs] going at 54% and 28 min ran, 23 minutes to go. I'll continue to watch, and switch back if it seems like they all run this way.
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Message 77299 - Posted: 22 Dec 2024, 19:51:02 UTC - in response to Message 77297.  
Last modified: 22 Dec 2024, 20:03:55 UTC

What's the normal amount of time these tasks take, or do they vary?
They vary quite a lot here, I have tasks, which take less than an hour of CPU-time while others take over a day (usually those with "data__9" in the name). For highest production I recommend running single thread tasks, i.e. set "Max # of threads for each MilkyWay@home task" to 1. Each task might run quite long than, but MT tasks are not very efficient, so you'll get more work done that way. For my Ryzen 5700G this is the difference I found between ST and MT tasks, you should get similar results.
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rcollins0618

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Message 77306 - Posted: 24 Dec 2024, 18:08:22 UTC - in response to Message 77299.  

Oh wow, that's counter-intuitive to me. nice hack!
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Message boards : Number crunching : CPU usage: Should I allow all threads (100% CPU Usage), or only number of cores (50% CPU in settings)?

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