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Message boards : Number crunching : Threading and processor affinity tool for Linux

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Hazel
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Joined: 2 Oct 17
Posts: 18
ID: 930140
Credit: 440,388,543
RAC: 66,427
Discovered 2 mega primesFound 1 prime in the 2019 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (7,554,867)PPS LLR Sapphire: Earned 20,000,000 credits (43,002,984)PSP LLR Turquoise: Earned 5,000,000 credits (5,137,739)SGS LLR Bronze: Earned 10,000 credits (15,886)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (87,930)PPS Sieve Double Silver: Earned 200,000,000 credits (242,877,179)AP 26/27 Jade: Earned 10,000,000 credits (13,762,372)GFN Double Bronze: Earned 100,000,000 credits (127,944,098)
Message 133511 - Posted: 4 Oct 2019 | 20:47:46 UTC
Last modified: 4 Oct 2019 | 21:02:32 UTC

Download

The latest version is here: https://github.com/hazelybell/scripts/blob/master/primegrid.py

Requirements


  • Python 3.7
  • numpy
  • scipy
  • util-linux (with the taskset command)



Benchmarking

To run the benchmark, stop primegrid and call:

python3.7 primegrid.py --benchmark-llr 'k*2^n+1'

For example:
python3.7 primegrid.py --benchmark-llr '25*2^3962242+1'


You can get a relevant prime for the project you're interested in from the subproject status page.

This will then run the benchmark with various thread counts, using HT or not, etc. The benchmark will run until it's relatively confident that the best strategy (thread count, HT, affinity) is the best.

Example output:
INFO:__main__:---------- Current results: INFO:__main__:Processors: 88% Threads: 7 Layout: free Tasks/day 48.68±0.60 INFO:__main__:Processors: 50% Threads: 4 Layout: free Tasks/day 50.39±0.48 INFO:__main__:Processors: 100% Threads: 1 Layout: free Tasks/day 51.79±0.48 INFO:__main__:Processors: 100% Threads: 1 Layout: spread Tasks/day 51.98±0.20 INFO:__main__:Processors: 100% Threads: 8 Layout: free Tasks/day 52.24±0.28 INFO:__main__:Processors: 50% Threads: 4 Layout: spread Tasks/day 52.90±0.30 INFO:__main__:Processors: 50% Threads: 2 Layout: free Tasks/day 57.94±0.69 INFO:__main__:Processors: 50% Threads: 2 Layout: spread Tasks/day 58.86±0.16 INFO:__main__:Processors: 100% Threads: 4 Layout: spread Tasks/day 61.50±0.59 INFO:__main__:Processors: 100% Threads: 4 Layout: clump Tasks/day 61.80±0.16 INFO:__main__:Processors: 100% Threads: 4 Layout: free Tasks/day 61.83±0.21 INFO:__main__:Processors: 100% Threads: 2 Layout: spread Tasks/day 62.34±1.40 INFO:__main__:Processors: 100% Threads: 2 Layout: free Tasks/day 64.24±1.65 INFO:__main__:Processors: 100% Threads: 2 Layout: clump Tasks/day 65.65±1.27 INFO:__main__:Processors: 50% Threads: 1 Layout: spread Tasks/day 72.00±3.00 INFO:__main__:Processors: 50% Threads: 1 Layout: free Tasks/day 72.51±2.46 INFO:__main__:----------


This indicates that the benchmark has completed a round, and that using 50% of the processors with tasks that have one thread each and letting Linux manage thread affinity was the fastest. It will continue running until it can be confident in it's choice, but you can stop whenever the error bars (the number after the ±) gets small enough for you, or if you're just sick of waiting.

Affinity

The tool currently supports 3 different affinity types:

'free': Let the OS manage affinity itself
'spread': Spread out the threads of a single task across different cores
'clump': Put the threads of a single task on the same cores

Example: Consider a 4-core CPU with hyperthreading. For a task with 2 threads, 'spread' will put the two threads on two different cores, and 'free' will put the two threads on the same core. For a task with 4 threads, 'spread' will put one thread on each core, while 'clump' will put all the threads on 2 cores.

Managing Affinity

If you decide that you want to run primegrid with an affinity layout other than 'free' you can run the script with '--layout clump' or '--layout spread' as root. The script will watch for BOINC to start primegrid LLR tasks and manage their affinity using 'taskset'.

Advanced Options

'--processors N' Benchmark only using N processors. This includes logical processors. For example on a 4-core processor with hyperthreading, setting '--processors 4' will only benchmark equivalent to setting 50% of CPUs in BOINC. This will reduce the number of different benchmarks run.

'--threads N' Benchmark only using tasks with N threads. This will reduce the number of different benchmarks to run.

'--layout free|spread|clump' Benchmark only tasks using the specified affinity layout. This will reduce the number of benchmarks to run.

Example for a 6-core hyperthreading processor: '--processors 6 --layout free' will only benchmark 1x6, 2x3, 3x2 and 6x1 tasks x threads without worrying about CPU affinity.

'--ci .90' Change the confidence interval used to compute the error bars. This will change the number of times the script re-runs benchmarks before it's "confident" in the results.

'--llr-executable path/to/llr' Specify a specific LLR executable.

Even more options: See '--help' output, but be wary, these can have unfortunate effects on your system.

Known Bugs

Systems with complicated topologies are not modelled by the script. That includes systems with multiple CPU sockets, NUMA, and Ryzen 3000-series CPUs. For thread counts strictly more than 2 with hyperthreading or more than 1 without hyperthreading the CPU affinity may be handled poorly. It is better to let the OS manage CPU affinity in these situations. For example, consider the Ryzen 3600X, a 6-core processor with hyperthreading. On this CPU, cores are organized into groups called CCXs, for which communication inside a single CCX is much faster than communication between cores in different CCXs. Thus plans like 4 threads x 3 tasks (100%) may have very poor performance if 'clump' or 'thread' is chosen. I plan supporting these systems better, eventually, if I can get my hands on one.

Future features


  • Manage CPU temperature (for systems which thermal throttle :x)
  • Model NUMA/multisocket/CCX CPU topologies
  • Manage C-states
  • Manage GPU driver affinity
  • Collect power usage and temperature stats



Example Results

PPS-DIV on a i7-7700K @ 4.7Ghz: use 1 thread, 50% CPUs, 'free' affinity
PPS-DIV on a i7-3770K @ 4.3Ghz: use 1 thread, 50% CPUs, 'free' affinity
PPS-DIV on a i7-8750H @ 45W: use 1 thread, 50% CPUs, 'spread' affinity
PPS-DIV on a i7-4700MQ @ 27W: use 1 thread, 50% CPUs, 'spread' affinity
PPS-DIV on a Xeon E3-1225 V2 @ stock: use 1 thread, 100% CPUs, 'spread' affinity
PPS-DIV on a i7-9700K @ 4.8Ghz: use 1 thread, 100% CPUs, 'free' affinity
SoB on a i7-7700K @ 4.7Ghz: use 4 threads, 50% CPUs, 'free' affinity

Conclusions

From experimenting with this script I've come to the following conclusions. Note that these are only for linux. Other operating systems handle threads very differently.


  • Using 1 thread on half the CPUs if hyperthreading or on all the CPUs if no hyperthreading is generally an okay choice. Even for SoB, using 1 thread isn't much slower than 4 threads.
  • Choosing whether or not to use all logical processors (threads) on a hyperthreading CPU matters.
  • Setting thread affinity can improve performance on some systems.
  • Best thread count changes depending on project. Both k and n can have an effect here and they can have different effects.



Feel free to post your results below!



____________
Crunched with love,
Hazel

Profile RobishProject donor
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Joined: 7 Jan 12
Posts: 1514
ID: 126266
Credit: 3,792,736,574
RAC: 5,004,771
Discovered the World's First AP27!!!Discovered 9 mega primesDiscovered 1 AP272018 Tour de Primes largest primeFound 4 primes in the 2018 Tour de PrimesFound 1 mega prime in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de PrimesFound 1 prime in the 2020 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (7,622,167)Cullen LLR Turquoise: Earned 5,000,000 credits (8,142,092)ESP LLR Turquoise: Earned 5,000,000 credits (6,404,450)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (6,466,498)PPS LLR Sapphire: Earned 20,000,000 credits (43,975,946)PSP LLR Turquoise: Earned 5,000,000 credits (7,758,266)SoB LLR Sapphire: Earned 20,000,000 credits (35,204,543)SR5 LLR Turquoise: Earned 5,000,000 credits (8,122,040)SGS LLR Turquoise: Earned 5,000,000 credits (5,150,681)TRP LLR Jade: Earned 10,000,000 credits (12,218,006)Woodall LLR Turquoise: Earned 5,000,000 credits (5,062,771)321 Sieve Turquoise: Earned 5,000,000 credits (6,582,489)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (7,892,369)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,515,338)PPS Sieve Double Gold: Earned 500,000,000 credits (782,206,840)TRP Sieve (suspended) Silver: Earned 100,000 credits (121,416)AP 26/27 Emerald: Earned 50,000,000 credits (83,576,896)GFN Double Ruby: Earned 2,000,000,000 credits (2,760,714,063)
Message 133515 - Posted: 4 Oct 2019 | 21:56:09 UTC

Wow! thanks for all your work that went into this Hazel, very cool! Appreciated 🙂
____________
My lucky numbers 10590941048576+1 and 181457032297751865536+1

Ken_g6Project donor
Volunteer developer
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Joined: 4 Jul 06
Posts: 894
ID: 3110
Credit: 171,264,482
RAC: 27,679
Found 2 primes in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de PrimesFound 1 prime in the 2020 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,010,094)Cullen LLR Amethyst: Earned 1,000,000 credits (1,125,935)ESP LLR Amethyst: Earned 1,000,000 credits (1,193,202)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (767,102)PPS LLR Jade: Earned 10,000,000 credits (16,755,782)PSP LLR Ruby: Earned 2,000,000 credits (4,060,731)SoB LLR Ruby: Earned 2,000,000 credits (3,860,053)SR5 LLR Amethyst: Earned 1,000,000 credits (1,709,799)SGS LLR Amethyst: Earned 1,000,000 credits (1,150,815)TPS LLR (retired) Bronze: Earned 10,000 credits (19,376)TRP LLR Amethyst: Earned 1,000,000 credits (1,834,402)Woodall LLR Amethyst: Earned 1,000,000 credits (1,156,424)321 Sieve Ruby: Earned 2,000,000 credits (2,915,071)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (8,584,236)Generalized Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (2,461,309)PPS Sieve Emerald: Earned 50,000,000 credits (79,291,322)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Silver: Earned 100,000 credits (352,129)TRP Sieve (suspended) Gold: Earned 500,000 credits (776,202)AP 26/27 Turquoise: Earned 5,000,000 credits (5,851,049)GFN Sapphire: Earned 20,000,000 credits (31,234,565)PSA Ruby: Earned 2,000,000 credits (4,154,617)
Message 133520 - Posted: 5 Oct 2019 | 0:42:03 UTC

What version of numpy is required? Ubuntu 18.04 LTS comes with 1:1.13.3-2ubuntu1, and it doesn't seem to have the multiarray numpy extension module. Whatever that is.

Hazel
Send message
Joined: 2 Oct 17
Posts: 18
ID: 930140
Credit: 440,388,543
RAC: 66,427
Discovered 2 mega primesFound 1 prime in the 2019 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (7,554,867)PPS LLR Sapphire: Earned 20,000,000 credits (43,002,984)PSP LLR Turquoise: Earned 5,000,000 credits (5,137,739)SGS LLR Bronze: Earned 10,000 credits (15,886)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (87,930)PPS Sieve Double Silver: Earned 200,000,000 credits (242,877,179)AP 26/27 Jade: Earned 10,000,000 credits (13,762,372)GFN Double Bronze: Earned 100,000,000 credits (127,944,098)
Message 133521 - Posted: 5 Oct 2019 | 1:52:35 UTC - in response to Message 133520.

Is it giving you an error? It shouldn't require any particular numpy feature... Numpy is just required for scipy.
____________
Crunched with love,
Hazel

Ken_g6Project donor
Volunteer developer
Avatar
Send message
Joined: 4 Jul 06
Posts: 894
ID: 3110
Credit: 171,264,482
RAC: 27,679
Found 2 primes in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de PrimesFound 1 prime in the 2020 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,010,094)Cullen LLR Amethyst: Earned 1,000,000 credits (1,125,935)ESP LLR Amethyst: Earned 1,000,000 credits (1,193,202)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (767,102)PPS LLR Jade: Earned 10,000,000 credits (16,755,782)PSP LLR Ruby: Earned 2,000,000 credits (4,060,731)SoB LLR Ruby: Earned 2,000,000 credits (3,860,053)SR5 LLR Amethyst: Earned 1,000,000 credits (1,709,799)SGS LLR Amethyst: Earned 1,000,000 credits (1,150,815)TPS LLR (retired) Bronze: Earned 10,000 credits (19,376)TRP LLR Amethyst: Earned 1,000,000 credits (1,834,402)Woodall LLR Amethyst: Earned 1,000,000 credits (1,156,424)321 Sieve Ruby: Earned 2,000,000 credits (2,915,071)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (8,584,236)Generalized Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (2,461,309)PPS Sieve Emerald: Earned 50,000,000 credits (79,291,322)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Silver: Earned 100,000 credits (352,129)TRP Sieve (suspended) Gold: Earned 500,000 credits (776,202)AP 26/27 Turquoise: Earned 5,000,000 credits (5,851,049)GFN Sapphire: Earned 20,000,000 credits (31,234,565)PSA Ruby: Earned 2,000,000 credits (4,154,617)
Message 133522 - Posted: 5 Oct 2019 | 6:10:04 UTC - in response to Message 133521.

I figured it out. python3.7 doesn't work with the 3.6 versions of numpy and scipy for some reason. So I had to make sure the apt versions of those were uninstalled. Then these commands set it up correctly:

sudo apt install python3.7 python3.7 -m pip install pip sudo -H python3.7 -m pip install scipy


(Installing scipy installs numpy too.)

Thanks! Your script looks useful, but I think it will take awhile to learn to use it well.

Hazel
Send message
Joined: 2 Oct 17
Posts: 18
ID: 930140
Credit: 440,388,543
RAC: 66,427
Discovered 2 mega primesFound 1 prime in the 2019 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (7,554,867)PPS LLR Sapphire: Earned 20,000,000 credits (43,002,984)PSP LLR Turquoise: Earned 5,000,000 credits (5,137,739)SGS LLR Bronze: Earned 10,000 credits (15,886)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (87,930)PPS Sieve Double Silver: Earned 200,000,000 credits (242,877,179)AP 26/27 Jade: Earned 10,000,000 credits (13,762,372)GFN Double Bronze: Earned 100,000,000 credits (127,944,098)
Message 133553 - Posted: 6 Oct 2019 | 2:51:38 UTC

The script now supports managing the CPU temperature.

Managing CPU Temperature

For some systems which thermal throttle, or are simply too loud, the script can manage the CPU temperature by specifying '--target-temp 95' or some other temperature in °C. The script will then change the maximum allowed CPU frequency until that temperature is met but not exceeded. Do not use this feature on overclocked systems.

Thermal throttling can degrade performance when the CPU runs too fast, overheats, and then runs very slowly until it cools down, then repeats this process over and over again. It is more efficient to run the CPU at a more consistent, intermediate speed.

____________
Crunched with love,
Hazel

Hazel
Send message
Joined: 2 Oct 17
Posts: 18
ID: 930140
Credit: 440,388,543
RAC: 66,427
Discovered 2 mega primesFound 1 prime in the 2019 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (7,554,867)PPS LLR Sapphire: Earned 20,000,000 credits (43,002,984)PSP LLR Turquoise: Earned 5,000,000 credits (5,137,739)SGS LLR Bronze: Earned 10,000 credits (15,886)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (87,930)PPS Sieve Double Silver: Earned 200,000,000 credits (242,877,179)AP 26/27 Jade: Earned 10,000,000 credits (13,762,372)GFN Double Bronze: Earned 100,000,000 credits (127,944,098)
Message 133997 - Posted: 17 Oct 2019 | 22:11:14 UTC

I did some benchmarks on my machines for the upcoming 321 challenge, using

python3 primegrid.py --benchmark-llr '3*2^15083930+1'


i7-7700K @ 4.7Ghz
Processors: 100% Threads: 1 Layout: spread Tasks/day 7.22±0.06 Processors: 100% Threads: 1 Layout: free Tasks/day 7.23±0.12 Processors: 100% Threads: 2 Layout: clump Tasks/day 7.54±0.16 Processors: 100% Threads: 2 Layout: free Tasks/day 7.66±0.24 Processors: 100% Threads: 2 Layout: spread Tasks/day 7.70±0.07 Processors: 50% Threads: 1 Layout: spread Tasks/day 7.88±0.32 Processors: 50% Threads: 1 Layout: free Tasks/day 7.88±0.24 Processors: 50% Threads: 4 Layout: free Tasks/day 8.32±0.49 Processors: 100% Threads: 4 Layout: clump Tasks/day 8.35±0.29 Processors: 50% Threads: 2 Layout: free Tasks/day 8.40±0.06 Processors: 50% Threads: 2 Layout: spread Tasks/day 8.44±0.22 Processors: 100% Threads: 4 Layout: free Tasks/day 8.46±0.13 Processors: 100% Threads: 4 Layout: spread Tasks/day 8.55±0.07 Processors: 50% Threads: 4 Layout: spread Tasks/day 8.67±0.08 Processors: 88% Threads: 7 Layout: free Tasks/day 9.04±0.04 Processors: 100% Threads: 8 Layout: free Tasks/day 9.13±0.03

Hyper-threading is really doing work on this CPU...

Xeon E3-1225 V2 @ stock
Processors: 100% Threads: 1 Layout: free Tasks/day 2.94±0.03 Processors: 100% Threads: 1 Layout: spread Tasks/day 2.95±0.22 Processors: 75% Threads: 3 Layout: free Tasks/day 2.98±0.12 Processors: 100% Threads: 2 Layout: free Tasks/day 3.18±0.29 Processors: 100% Threads: 2 Layout: spread Tasks/day 3.26±0.06 Processors: 100% Threads: 4 Layout: spread Tasks/day 3.79±0.01 Processors: 100% Threads: 4 Layout: free Tasks/day 3.81±0.01

Basically as expected, multithreading is faster on this 4-core CPU without HT.

i7-3770K @ 4.3Ghz couldn't decide between these three:
Processors: 100% Threads: 8 Layout: free Tasks/day 4.59±0.03 Processors: 88% Threads: 7 Layout: free Tasks/day 4.59±0.04 Processors: 50% Threads: 4 Layout: spread Tasks/day 4.63±0.02

Which is honestly, pretty fascinating. This CPU is right on the line between HT helping and hurting.

i7-8750H @ 45W couldn't decide between these:
Processors: 100% Threads: 6 Layout: free Tasks/day 5.86±0.13 Processors: 92% Threads: 11 Layout: free Tasks/day 5.88±0.08 Processors: 50% Threads: 1 Layout: spread Tasks/day 5.95±0.06 Processors: 50% Threads: 3 Layout: free Tasks/day 5.96±0.11 Processors: 100% Threads: 6 Layout: spread Tasks/day 5.97±0.07 Processors: 50% Threads: 1 Layout: free Tasks/day 5.97±0.03 Processors: 50% Threads: 6 Layout: spread Tasks/day 6.02±0.07 Processors: 50% Threads: 2 Layout: spread Tasks/day 6.04±0.04 Processors: 50% Threads: 3 Layout: spread Tasks/day 6.04±0.07

This is a laptop and it's probably just trading off power budget between the RAM and the cores.



____________
Crunched with love,
Hazel

GDB
Send message
Joined: 15 Nov 11
Posts: 203
ID: 119185
Credit: 2,281,644,824
RAC: 1,141,997
321 LLR Jade: Earned 10,000,000 credits (12,924,181)Cullen LLR Turquoise: Earned 5,000,000 credits (5,039,267)ESP LLR Turquoise: Earned 5,000,000 credits (5,240,818)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,387,851)PPS LLR Ruby: Earned 2,000,000 credits (3,367,767)PSP LLR Turquoise: Earned 5,000,000 credits (6,084,153)SoB LLR Jade: Earned 10,000,000 credits (15,977,263)SR5 LLR Ruby: Earned 2,000,000 credits (3,147,812)SGS LLR Ruby: Earned 2,000,000 credits (2,918,931)TRP LLR Turquoise: Earned 5,000,000 credits (5,140,321)Woodall LLR Turquoise: Earned 5,000,000 credits (5,099,498)321 Sieve Ruby: Earned 2,000,000 credits (2,554,808)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (2,647,915)Generalized Cullen/Woodall Sieve (suspended) Jade: Earned 10,000,000 credits (11,373,349)PPS Sieve Double Bronze: Earned 100,000,000 credits (117,277,321)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (4,080,038)TRP Sieve (suspended) Turquoise: Earned 5,000,000 credits (7,803,337)AP 26/27 Emerald: Earned 50,000,000 credits (51,499,734)GFN Double Bronze: Earned 100,000,000 credits (161,783,359)PSA Double Amethyst: Earned 1,000,000,000 credits (1,855,472,561)
Message 134041 - Posted: 19 Oct 2019 | 9:48:01 UTC - in response to Message 133997.

It's not clear to me, how many tasks you were running?

Hazel
Send message
Joined: 2 Oct 17
Posts: 18
ID: 930140
Credit: 440,388,543
RAC: 66,427
Discovered 2 mega primesFound 1 prime in the 2019 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (7,554,867)PPS LLR Sapphire: Earned 20,000,000 credits (43,002,984)PSP LLR Turquoise: Earned 5,000,000 credits (5,137,739)SGS LLR Bronze: Earned 10,000 credits (15,886)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (87,930)PPS Sieve Double Silver: Earned 200,000,000 credits (242,877,179)AP 26/27 Jade: Earned 10,000,000 credits (13,762,372)GFN Double Bronze: Earned 100,000,000 credits (127,944,098)
Message 134045 - Posted: 19 Oct 2019 | 16:31:02 UTC - in response to Message 134041.

It's not clear to me, how many tasks you were running?


It depends on the CPU... it's listed in % like how BOINC is configured. That is, i7-7700K is a 4C/8T CPU so "Processors: 50% Threads: 2" means to run 2 tasks because 50% of 8 is 4, and 4/2 is 2.
____________
Crunched with love,
Hazel

GDB
Send message
Joined: 15 Nov 11
Posts: 203
ID: 119185
Credit: 2,281,644,824
RAC: 1,141,997
321 LLR Jade: Earned 10,000,000 credits (12,924,181)Cullen LLR Turquoise: Earned 5,000,000 credits (5,039,267)ESP LLR Turquoise: Earned 5,000,000 credits (5,240,818)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,387,851)PPS LLR Ruby: Earned 2,000,000 credits (3,367,767)PSP LLR Turquoise: Earned 5,000,000 credits (6,084,153)SoB LLR Jade: Earned 10,000,000 credits (15,977,263)SR5 LLR Ruby: Earned 2,000,000 credits (3,147,812)SGS LLR Ruby: Earned 2,000,000 credits (2,918,931)TRP LLR Turquoise: Earned 5,000,000 credits (5,140,321)Woodall LLR Turquoise: Earned 5,000,000 credits (5,099,498)321 Sieve Ruby: Earned 2,000,000 credits (2,554,808)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (2,647,915)Generalized Cullen/Woodall Sieve (suspended) Jade: Earned 10,000,000 credits (11,373,349)PPS Sieve Double Bronze: Earned 100,000,000 credits (117,277,321)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (4,080,038)TRP Sieve (suspended) Turquoise: Earned 5,000,000 credits (7,803,337)AP 26/27 Emerald: Earned 50,000,000 credits (51,499,734)GFN Double Bronze: Earned 100,000,000 credits (161,783,359)PSA Double Amethyst: Earned 1,000,000,000 credits (1,855,472,561)
Message 134049 - Posted: 19 Oct 2019 | 18:27:35 UTC - in response to Message 134045.

It's not clear to me, how many tasks you were running?


It depends on the CPU... it's listed in % like how BOINC is configured. That is, i7-7700K is a 4C/8T CPU so "Processors: 50% Threads: 2" means to run 2 tasks because 50% of 8 is 4, and 4/2 is 2.


For me, it would be so much easier to understand your tests if you explicitly say tasks x threads for each test. Instead of having to guess, and getting it wrong.

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Message boards : Number crunching : Threading and processor affinity tool for Linux

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