Hello everyone, my first post here :)
I just want to share my observation on the BOINC performance.

I'm running Rosetta at my main, home PC based on Ryzen 3 2200g, virtualization ON, base speed 3.75 GHz. Had it set to 100% CPUs, 75% CPU time with 3 minutes inactivity, pretty standard settings but tried 50% CPU @ 100% CPU time and many other as well.
Yesterday changed the settings again because of the fan noise and exscesive heat so BOINC is now set to 100% CPUs, 36% of CPU time and always run, not just when PC is iddle, which seems to be sweet-spot for this machine. Looks like tasks are being calculated tad faster as a background process then leaving the computing for the night, not to mention, I can freely use my PC while having all in all up to 14 hours of instead of 6-10 dedicated for the tasks. Not a hiccup even during online gaming sessions and without turning my room into sauna ;)

BOINC is now set to 100% CPUs, 36% of CPU time

Not a good idea.
What that means is it will take a minimum of 24 hours to process an 8 Hour Target CPU time task, longer still if "Suspend when non-BOINC CPU usage is above --- %" is set to anyhting lower than 85% It is better to run at 100% of CPU time & limit the number of Cores being used if your system cooling isn't up to the job.
That way you won't have problems with deadlines; and to help avoid deadline issues it's worth running with little or no cache.

   Other	
                                Store at least 0.4 days of work
                     Store up to an additional 0.02 days of work

is about as large a cache as you really need.

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Grant
Darwin NT

Cache isn't real problem, as I got 120GB dedicated HDD just for the project, my settings for storing is 0,1 days of work and additional 0,5 days of work, and my jobs are currently due in the next 2-3 days. And I understand that, on paper, it should work as you said and will be monitoring if it will be like that, yet at the moment, it looks like there are less errors, holds and so on.

Cache isn't real problem, as I got 120GB dedicated HDD just for the project,

The cache size isn't about disk storage issues, it's about missing deadlines. If BOINC expects a Task to take a certain time, then changes occur that mean it will take 3 times as long (or longer) to actually proces the work than BONIC expects, then there is a chance of missed deadlines while it adjusts to those changes. With a small or no cache, the risk of missed deadlines is greatly reduced.

my settings for storing is 0,1 days of work and additional 0,5 days of work,

As they are, it will tend run down till there is only 0.1 days of work left, then get half a days worth of work. If you swap those values around then you will maintain around a half a days cache.

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Grant
Darwin NT

There are many potential bottlenecks is processing work on a computer. If you need to write to disk, is the disk busy writting data for other tasks? If you need to examine the contents of memory, is the memory page out in the swap space? Is the page available in the on-processor memory cache? Etc.

R@h tasks are typically fairly high memory usage. As such, there is a lot of interaction between the active process and memory. As such, processors with larger L2/L3 caches often do better than systems with smaller caches. It improves the odds of any given memory access to be serviced immediately.

By running all of your 4 cores at a fractional percentage, you have 4 active tasks with memory footprints and contention for L2/L3 cache. By splitting the work across 4 tasks, you diminish the odds of finding the active things in the cache. If instead you run 2 tasks at 100% of CPU, there will only be two tasks worth of contention for cache rather than 4 tasks worth. Thus improving the odds of getting higher performance cache hits. It will also help the system be more responsive to higher priority tasks because of the reduced memory/cache footprint of the BOINC tasks.

So yes, there are certainly cases where less is more. It seems the thing you are most focused on is fan speed/noise. You would have to try it and see, but running 2 cores at 100% would have some other efficiency gains over running 4 cores at 36%, if the resulting fan speed allows it. If fan kicks back to higher speed, then I would suggest running 2 cores (50% of CPUs), for something less than 100% of the time, rather than all 4.

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Rosetta Moderator: Mod.Sense

There are many potential bottlenecks is processing work on a computer. If you need to write to disk, is the disk busy writting data for other tasks? If you need to examine the contents of memory, is the memory page out in the swap space? Is the page available in the on-processor memory cache? Etc.

R@h tasks are typically fairly high memory usage. As such, there is a lot of interaction between the active process and memory. As such, processors with larger L2/L3 caches often do better than systems with smaller caches. It improves the odds of any given memory access to be serviced immediately.

By running all of your 4 cores at a fractional percentage, you have 4 active tasks with memory footprints and contention for L2/L3 cache. By splitting the work across 4 tasks, you diminish the odds of finding the active things in the cache. If instead you run 2 tasks at 100% of CPU, there will only be two tasks worth of contention for cache rather than 4 tasks worth. Thus improving the odds of getting higher performance cache hits. It will also help the system be more responsive to higher priority tasks because of the reduced memory/cache footprint of the BOINC tasks.

So yes, there are certainly cases where less is more. It seems the thing you are most focused on is fan speed/noise. You would have to try it and see, but running 2 cores at 100% would have some other efficiency gains over running 4 cores at 36%, if the resulting fan speed allows it. If fan kicks back to higher speed, then I would suggest running 2 cores (50% of CPUs), for something less than 100% of the time, rather than all 4.

I agree with everything above but might I add, if your system is still overheating when running only 2 of the 4 cores then I would examine the cooling system and see if there was a problem - maybe a build up of dust in the heat sink or a blocked filter. It happens all too easily as I have found to my cost. (As well as forgetting that I’d changed the bios settings to a manual fan profile in the days before I started crunching which definitely did not work with high cpu usage).

I surely will try those settings of 2 cores @ 100%. I'm having some issues with the fans and motherboard to hit a good spot between proper cooling, good performance and acceptable noise levels and will try to make some improvements.
Thanks for hints.