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Message boards : Proth Prime Search : PPS-MEGA: Smaller FFT longer crunch time ?

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Profile Eudy SilvaProject donor
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Found 2 primes in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de Primes321 LLR Gold: Earned 500,000 credits (834,329)Cullen LLR Amethyst: Earned 1,000,000 credits (1,011,118)ESP LLR Gold: Earned 500,000 credits (988,114)Generalized Cullen/Woodall LLR Amethyst: Earned 1,000,000 credits (1,004,746)PPS LLR Turquoise: Earned 5,000,000 credits (5,977,139)PSP LLR Gold: Earned 500,000 credits (742,121)SoB LLR Ruby: Earned 2,000,000 credits (2,113,239)SR5 LLR Ruby: Earned 2,000,000 credits (2,391,286)SGS LLR Amethyst: Earned 1,000,000 credits (1,162,202)TRP LLR Amethyst: Earned 1,000,000 credits (1,309,179)Woodall LLR Amethyst: Earned 1,000,000 credits (1,001,901)321 Sieve Amethyst: Earned 1,000,000 credits (1,036,805)Generalized Cullen/Woodall Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,005,331)PPS Sieve Emerald: Earned 50,000,000 credits (63,539,979)AP 26/27 Sapphire: Earned 20,000,000 credits (21,282,352)GFN Sapphire: Earned 20,000,000 credits (25,471,331)
Message 130064 - Posted: 1 Jun 2019 | 22:59:39 UTC
Last modified: 1 Jun 2019 | 23:43:00 UTC

Is this normal behavior ?
I'm crunching PPS-MEGA and noticed that tasks with a 240K FFT take 28-33% longer to crunch than those with a 256K FFT.
Por instance, typical tasks:

https://www.primegrid.com/result.php?resultid=1003602409
BOINC llr wrapper (version 8.00)
Using Jean Penne's llr (64 bit)
LLR Program - Version 3.8.23, using Gwnum Library Version 29.8
LLR command line: primegrid_cllr.exe -d -oDiskWriteTime=1 -oThreadsPerTest=4 llr.in
Using all-complex FMA3 FFT length 256K, Pass1=128, Pass2=2K, clm=2, 4 threads, a = 7
Run time: 1,076.00 seconds

https://www.primegrid.com/result.php?resultid=1003588100
BOINC llr wrapper (version 8.00)
Using Jean Penne's llr (64 bit)
LLR Program - Version 3.8.23, using Gwnum Library Version 29.8
LLR command line: primegrid_cllr.exe -d -oDiskWriteTime=1 -oThreadsPerTest=4 llr.in
Using all-complex FMA3 FFT length 240K, Pass1=1280, Pass2=192, clm=2, 4 threads, a = 3
Run time: 1,442.00 seconds

Am I missing something ?
Edit: Maybe those different Pass1, Pass2 and "a" values do affect the crunch time?
____________
"Accidit in puncto, quod non contingit in anno."
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Profile Crun-chiProject donor
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Eliminated 1 conjecture "k"Found 1 prime in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de Primes321 LLR Silver: Earned 100,000 credits (229,492)Cullen LLR Silver: Earned 100,000 credits (110,733)PPS LLR Ruby: Earned 2,000,000 credits (2,982,482)PSP LLR Silver: Earned 100,000 credits (104,385)SoB LLR Silver: Earned 100,000 credits (106,117)SR5 LLR Silver: Earned 100,000 credits (139,802)SGS LLR Amethyst: Earned 1,000,000 credits (1,073,792)TRP LLR Silver: Earned 100,000 credits (122,712)Woodall LLR Silver: Earned 100,000 credits (122,944)321 Sieve Silver: Earned 100,000 credits (104,900)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (2,000,599)Generalized Cullen/Woodall Sieve (suspended) Gold: Earned 500,000 credits (515,556)PPS Sieve Jade: Earned 10,000,000 credits (11,215,485)TRP Sieve (suspended) Silver: Earned 100,000 credits (255,612)AP 26/27 Ruby: Earned 2,000,000 credits (2,575,874)GFN Sapphire: Earned 20,000,000 credits (23,152,487)PSA Turquoise: Earned 5,000,000 credits (7,522,050)
Message 130067 - Posted: 1 Jun 2019 | 23:45:34 UTC - in response to Message 130064.

This is ok, you are missed fact that you using 4 cores on candidate that have only 240/256K
So your resources are better exploited on 256K candidate and hence has lower computing time
But that is my version :)
____________
271643232^131072+1 GENERALIZED FERMAT :)
93*10^1029523-1 REPDIGIT PRIME
31*332^367560+1 CRUS PRIME
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Profile Michael GoetzProject donor
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The "Shut up already!" badge:  This loud mouth has mansplained on the forums over 10 thousand times!  Sheesh!!!Discovered the World's First GFN-19 prime!!!Discovered 1 mega primeFound 1 prime in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,063,182)Cullen LLR Ruby: Earned 2,000,000 credits (2,005,249)ESP LLR Ruby: Earned 2,000,000 credits (3,820,430)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,145,754)PPS LLR Ruby: Earned 2,000,000 credits (2,773,744)PSP LLR Ruby: Earned 2,000,000 credits (2,632,269)SoB LLR Sapphire: Earned 20,000,000 credits (34,158,496)SR5 LLR Turquoise: Earned 5,000,000 credits (8,293,415)SGS LLR Ruby: Earned 2,000,000 credits (2,012,781)TRP LLR Ruby: Earned 2,000,000 credits (2,737,347)Woodall LLR Ruby: Earned 2,000,000 credits (2,195,123)321 Sieve Turquoise: Earned 5,000,000 credits (5,046,112)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,170,256)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,059,304)PPS Sieve Sapphire: Earned 20,000,000 credits (20,110,788)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,035,522)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,051,121)AP 26/27 Turquoise: Earned 5,000,000 credits (7,118,397)GFN Emerald: Earned 50,000,000 credits (64,595,124)PSA Jade: Earned 10,000,000 credits (10,135,447)
Message 130069 - Posted: 2 Jun 2019 | 1:27:49 UTC - in response to Message 130064.

Guess: FFT sizes that are a power of two are faster than those that aren't.
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Please do not PM me with support questions. Ask on the forums instead. Thank you!

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Profile composite
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Discovered 2 mega primesFound 1 prime in the 2018 Tour de Primes321 LLR Turquoise: Earned 5,000,000 credits (5,090,406)Cullen LLR Gold: Earned 500,000 credits (776,297)ESP LLR Ruby: Earned 2,000,000 credits (2,160,301)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,056,207)PPS LLR Jade: Earned 10,000,000 credits (10,631,176)PSP LLR Ruby: Earned 2,000,000 credits (3,777,949)SoB LLR Sapphire: Earned 20,000,000 credits (20,233,229)SR5 LLR Turquoise: Earned 5,000,000 credits (5,978,312)SGS LLR Ruby: Earned 2,000,000 credits (2,932,085)TRP LLR Turquoise: Earned 5,000,000 credits (7,021,680)Woodall LLR Amethyst: Earned 1,000,000 credits (1,693,614)321 Sieve Turquoise: Earned 5,000,000 credits (9,475,479)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,571,178)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,009,610)PPS Sieve Double Silver: Earned 200,000,000 credits (233,250,224)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,165,888)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,071,454)AP 26/27 Ruby: Earned 2,000,000 credits (2,544,827)GFN Sapphire: Earned 20,000,000 credits (48,678,064)PSA Double Bronze: Earned 100,000,000 credits (102,762,384)
Message 130071 - Posted: 2 Jun 2019 | 5:19:02 UTC - in response to Message 130069.

Guess: FFT sizes that are a power of two are faster than those that aren't.

This sounds like a potential optimization - step up FFT to the next power of two. Care to run some experiments?

Profile Michael GoetzProject donor
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Joined: 21 Jan 10
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The "Shut up already!" badge:  This loud mouth has mansplained on the forums over 10 thousand times!  Sheesh!!!Discovered the World's First GFN-19 prime!!!Discovered 1 mega primeFound 1 prime in the 2018 Tour de PrimesFound 1 prime in the 2019 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,063,182)Cullen LLR Ruby: Earned 2,000,000 credits (2,005,249)ESP LLR Ruby: Earned 2,000,000 credits (3,820,430)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,145,754)PPS LLR Ruby: Earned 2,000,000 credits (2,773,744)PSP LLR Ruby: Earned 2,000,000 credits (2,632,269)SoB LLR Sapphire: Earned 20,000,000 credits (34,158,496)SR5 LLR Turquoise: Earned 5,000,000 credits (8,293,415)SGS LLR Ruby: Earned 2,000,000 credits (2,012,781)TRP LLR Ruby: Earned 2,000,000 credits (2,737,347)Woodall LLR Ruby: Earned 2,000,000 credits (2,195,123)321 Sieve Turquoise: Earned 5,000,000 credits (5,046,112)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,170,256)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,059,304)PPS Sieve Sapphire: Earned 20,000,000 credits (20,110,788)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,035,522)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,051,121)AP 26/27 Turquoise: Earned 5,000,000 credits (7,118,397)GFN Emerald: Earned 50,000,000 credits (64,595,124)PSA Jade: Earned 10,000,000 credits (10,135,447)
Message 130083 - Posted: 2 Jun 2019 | 11:43:58 UTC - in response to Message 130071.

Guess: FFT sizes that are a power of two are faster than those that aren't.

This sounds like a potential optimization - step up FFT to the next power of two. Care to run some experiments?


Thank you for volunteering! :)

As an aside... this is something better discussed with the people who, you know, actually develop this software. If you do find something that could be optimized, they're the ones that would benefit from that knowledge. If there's a question that only could be answered by a developer, it's beneficial to actually ask the developers.
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My lucky number is 75898524288+1

288larssonProject donor
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Discovered 24 mega primesEliminated 1 conjecture "k"Found 3 primes in the 2018 Tour de PrimesFound 2 mega primes in the 2018 Tour de Primes2019 Tour de Primes highest prime scoreFound 4 primes in the 2019 Tour de PrimesFound 1 mega prime in the 2019 Tour de Primes321 LLR Sapphire: Earned 20,000,000 credits (40,123,542)Cullen LLR Jade: Earned 10,000,000 credits (12,048,927)ESP LLR Sapphire: Earned 20,000,000 credits (43,370,685)Generalized Cullen/Woodall LLR Sapphire: Earned 20,000,000 credits (45,815,726)PPS LLR Double Silver: Earned 200,000,000 credits (267,638,946)PSP LLR Sapphire: Earned 20,000,000 credits (36,206,048)SoB LLR Emerald: Earned 50,000,000 credits (58,139,244)SR5 LLR Sapphire: Earned 20,000,000 credits (29,215,459)SGS LLR Jade: Earned 10,000,000 credits (14,824,366)TRP LLR Sapphire: Earned 20,000,000 credits (49,012,758)Woodall LLR Jade: Earned 10,000,000 credits (13,898,840)321 Sieve Silver: Earned 100,000 credits (200,282)Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (6,081,963)Generalized Cullen/Woodall Sieve (suspended) Jade: Earned 10,000,000 credits (13,723,448)PPS Sieve Double Amethyst: Earned 1,000,000,000 credits (1,111,509,432)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (14,372,149)TRP Sieve (suspended) Jade: Earned 10,000,000 credits (11,393,528)AP 26/27 Sapphire: Earned 20,000,000 credits (20,598,860)GFN Double Amethyst: Earned 1,000,000,000 credits (1,167,640,169)PSA Double Silver: Earned 200,000,000 credits (226,139,676)
Message 130107 - Posted: 3 Jun 2019 | 13:04:07 UTC

Hi
llr3.8.23 mostly using FFT length 240K
llr3.8.21 mostly using FFT length 256K

Test on host
http://www.primegrid.com/results.php?hostid=946202

Profile dannyridel
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ESP LLR Bronze: Earned 10,000 credits (25,105)PPS LLR Bronze: Earned 10,000 credits (25,167)SR5 LLR Bronze: Earned 10,000 credits (14,479)TRP LLR Bronze: Earned 10,000 credits (13,509)321 Sieve Bronze: Earned 10,000 credits (21,346)Generalized Cullen/Woodall Sieve (suspended) Bronze: Earned 10,000 credits (30,033)PPS Sieve Silver: Earned 100,000 credits (195,518)PSA Bronze: Earned 10,000 credits (54,175)
Message 130108 - Posted: 3 Jun 2019 | 13:09:03 UTC - in response to Message 130107.

aww, I think 256k is faster
host 946571
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Message boards : Proth Prime Search : PPS-MEGA: Smaller FFT longer crunch time ?

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