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Message boards : Project Staging Area : GFN Errors

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geeknikProject donor
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Joined: 28 Feb 09
Posts: 108
ID: 36279
Credit: 48,474,523
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Eliminated 2 conjecture "k"sFound 2 primes in the 2020 Tour de Primes321 LLR Amethyst: Earned 1,000,000 credits (1,070,870)Cullen LLR Amethyst: Earned 1,000,000 credits (1,184,574)ESP LLR Amethyst: Earned 1,000,000 credits (1,085,454)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (669,174)PPS LLR Turquoise: Earned 5,000,000 credits (9,536,881)PSP LLR Silver: Earned 100,000 credits (254,126)SoB LLR Bronze: Earned 10,000 credits (42,047)SR5 LLR Gold: Earned 500,000 credits (761,816)SGS LLR Ruby: Earned 2,000,000 credits (2,329,650)TRP LLR Silver: Earned 100,000 credits (166,445)Woodall LLR Gold: Earned 500,000 credits (575,331)321 Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,665,359)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (254,689)Generalized Cullen/Woodall Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,700,548)PPS Sieve Jade: Earned 10,000,000 credits (10,264,265)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Silver: Earned 100,000 credits (411,714)TRP Sieve (suspended) Gold: Earned 500,000 credits (717,962)AP 26/27 Ruby: Earned 2,000,000 credits (2,839,419)GFN Ruby: Earned 2,000,000 credits (2,080,358)PSA Jade: Earned 10,000,000 credits (10,863,835)
Message 19426 - Posted: 1 Dec 2009 | 2:15:07 UTC

I just started doing some GFN work and I'm seeing some of the following and I'm wondering if this is normal:

maxEr exceeded for xxxxx^xxxx+1, 0.5000 > 0.4500

And then some of these:

xxxxx^xxxx+1 is not prime. Residue roundofferr

Thanks.
____________
FUCK THIS PROJECT AND THEIR COMMIE BULLSHIT POLITICS

HonzaProject donor
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Joined: 15 Aug 05
Posts: 1887
ID: 352
Credit: 3,068,315,895
RAC: 1,005,601
Discovered 7 mega primesEliminated 4 conjecture "k"sFound 2 primes in the 2018 Tour de PrimesFound 1 prime in the 2018 Tour de Primes Mountain Stage2019 Tour de Primes largest primeFound 4 primes in the 2019 Tour de PrimesFound 1 mega prime in the 2019 Tour de PrimesFound 1 prime in the 2019 Tour de Primes Mountain StageFound 1 prime in the 2020 Tour de Primes321 LLR Emerald: Earned 50,000,000 credits (91,282,326)Cullen LLR Emerald: Earned 50,000,000 credits (57,403,007)ESP LLR Emerald: Earned 50,000,000 credits (50,853,190)Generalized Cullen/Woodall LLR Emerald: Earned 50,000,000 credits (50,309,119)PPS LLR Double Bronze: Earned 100,000,000 credits (122,476,468)PSP LLR Emerald: Earned 50,000,000 credits (50,563,867)SoB LLR Double Bronze: Earned 100,000,000 credits (101,502,109)SR5 LLR Double Bronze: Earned 100,000,000 credits (101,883,529)SGS LLR Emerald: Earned 50,000,000 credits (53,154,727)TPS LLR (retired) Bronze: Earned 10,000 credits (43,033)TRP LLR Double Bronze: Earned 100,000,000 credits (100,338,924)Woodall LLR Emerald: Earned 50,000,000 credits (50,956,094)321 Sieve (suspended) Double Bronze: Earned 100,000,000 credits (115,948,450)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,142,109)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,504,945)PPS Sieve Double Gold: Earned 500,000,000 credits (513,057,580)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,288,222)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,149,354)AP 26/27 Double Silver: Earned 200,000,000 credits (232,724,773)GFN Double Gold: Earned 500,000,000 credits (745,545,332)PSA Double Gold: Earned 500,000,000 credits (535,232,795)
Message 19431 - Posted: 1 Dec 2009 | 13:36:54 UTC

Win or Linux? 32-bit or 64-bit?
What Genefer app is running?
For what number? Like 170588^32768+1. Or at least what Port?
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rogue
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PPS LLR Bronze: Earned 10,000 credits (31,229)PSA Jade: Earned 10,000,000 credits (18,533,435)
Message 19432 - Posted: 1 Dec 2009 | 14:06:13 UTC - in response to Message 19426.

I just started doing some GFN work and I'm seeing some of the following and I'm wondering if this is normal:

maxEr exceeded for xxxxx^xxxx+1, 0.5000 > 0.4500

And then some of these:

xxxxx^xxxx+1 is not prime. Residue roundofferr

Thanks.


This is actually OK. You can find information on round-off errors here, http://en.wikipedia.org/wiki/Round-off_error.

All of the programs used by PRPNet (LLR, phrot, PFGW, and genefer) use the FPU to do the math. Each of these programs has internal checks to look for round-off errors during the PRP/primality test. When such an error is detected, these programs terminate immediately. LLR and genefer are unable to recover from such errors. In other works, no matter what you try to do, LLR and genefer will not be able to complete a valid test for a number that gets a round-off errors. phrot tries to auto-recover by changing the FFT size without user intervention. PFGW cannot auto-recover, but the PRPNet client is smart enough to detect such errors from PFGW and will then try again by passing the -a1 or -a2 switch to PFGW, which changes the FFT size. Increasing the FFT size eliminates the round-off errors (most of the time).

In the case of genefer there are three versions of it. For genefx64, we sacrifice the most accuracy for speed. For genefer80, we sacrifice the most speed for accuracy. The original genefer is in the middle. This means that as b increases, geneferx64 is more likely to get a round-off error. When the PRPNet client detects that error it will retry to test with genefer. If it fails with genefer, it will retry with genefer80. If genefer80 fails, then the number cannot be tested by PRPNet (at this time).

If genefx64 detects a round-off error and the PRPNet client is not configured to run genefer or genefer80, then it will return roundofferr as the residue to the server along with the version(s) of genefer that got roundoff errors. The server will then hold that number until a client that can run genefer or genefer80 connects. It will not resend that same candidate to clients that only run genefx64.

What gets confusing is that as b increases, the chance of a round-off error increases, but is not necessarily guaranteed. For example if b=123456 gets a round-off error with genefx64, it does not mean that all b>123456 will also get a round-off error. There is a point where all b above a certain value will get a round-off error, but we don't know what those limits are. There is a "-l" command line option for each version of genefer that tries to determine the lowest b where round-off errors start occurring. It isn't perfect because it only runs a few iterations of a PRP test for each b and round-off errors could occur after the last iteration tested. PRPNet doesn't use this option, but it will give you can idea regarding the upper limit for b for each n. I might eventually modify the client to use those limits and pass them to the server so that the server doesn't hand out tests to clients where the test could fail due to a round-off error.

Eventually I will modify the client and server to use PFGW for the PRP test if genefer80 gets a round-off error. The big problem with using PFGW instead of genefer for GFN testing is that the residues are not compatible.

I hope that answers your questions.

And yes, this should probably make its way into the prpclient readme file.

HonzaProject donor
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Joined: 15 Aug 05
Posts: 1887
ID: 352
Credit: 3,068,315,895
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Discovered 7 mega primesEliminated 4 conjecture "k"sFound 2 primes in the 2018 Tour de PrimesFound 1 prime in the 2018 Tour de Primes Mountain Stage2019 Tour de Primes largest primeFound 4 primes in the 2019 Tour de PrimesFound 1 mega prime in the 2019 Tour de PrimesFound 1 prime in the 2019 Tour de Primes Mountain StageFound 1 prime in the 2020 Tour de Primes321 LLR Emerald: Earned 50,000,000 credits (91,282,326)Cullen LLR Emerald: Earned 50,000,000 credits (57,403,007)ESP LLR Emerald: Earned 50,000,000 credits (50,853,190)Generalized Cullen/Woodall LLR Emerald: Earned 50,000,000 credits (50,309,119)PPS LLR Double Bronze: Earned 100,000,000 credits (122,476,468)PSP LLR Emerald: Earned 50,000,000 credits (50,563,867)SoB LLR Double Bronze: Earned 100,000,000 credits (101,502,109)SR5 LLR Double Bronze: Earned 100,000,000 credits (101,883,529)SGS LLR Emerald: Earned 50,000,000 credits (53,154,727)TPS LLR (retired) Bronze: Earned 10,000 credits (43,033)TRP LLR Double Bronze: Earned 100,000,000 credits (100,338,924)Woodall LLR Emerald: Earned 50,000,000 credits (50,956,094)321 Sieve (suspended) Double Bronze: Earned 100,000,000 credits (115,948,450)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,142,109)Generalized Cullen/Woodall Sieve (suspended) Emerald: Earned 50,000,000 credits (50,504,945)PPS Sieve Double Gold: Earned 500,000,000 credits (513,057,580)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,288,222)TRP Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,149,354)AP 26/27 Double Silver: Earned 200,000,000 credits (232,724,773)GFN Double Gold: Earned 500,000,000 credits (745,545,332)PSA Double Gold: Earned 500,000,000 credits (535,232,795)
Message 19433 - Posted: 1 Dec 2009 | 15:01:01 UTC

Thanks for in-depth answer.

There are some b limits and speed comparation for each genefer version in GFN Sieve Discussion thread. Good enough to get an idea...
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My stats
Badge score: 1*1 + 5*1 + 8*3 + 9*11 + 10*1 + 11*1 + 12*3 = 186

geeknikProject donor
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Joined: 28 Feb 09
Posts: 108
ID: 36279
Credit: 48,474,523
RAC: 0
Eliminated 2 conjecture "k"sFound 2 primes in the 2020 Tour de Primes321 LLR Amethyst: Earned 1,000,000 credits (1,070,870)Cullen LLR Amethyst: Earned 1,000,000 credits (1,184,574)ESP LLR Amethyst: Earned 1,000,000 credits (1,085,454)Generalized Cullen/Woodall LLR Gold: Earned 500,000 credits (669,174)PPS LLR Turquoise: Earned 5,000,000 credits (9,536,881)PSP LLR Silver: Earned 100,000 credits (254,126)SoB LLR Bronze: Earned 10,000 credits (42,047)SR5 LLR Gold: Earned 500,000 credits (761,816)SGS LLR Ruby: Earned 2,000,000 credits (2,329,650)TRP LLR Silver: Earned 100,000 credits (166,445)Woodall LLR Gold: Earned 500,000 credits (575,331)321 Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,665,359)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (254,689)Generalized Cullen/Woodall Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,700,548)PPS Sieve Jade: Earned 10,000,000 credits (10,264,265)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Silver: Earned 100,000 credits (411,714)TRP Sieve (suspended) Gold: Earned 500,000 credits (717,962)AP 26/27 Ruby: Earned 2,000,000 credits (2,839,419)GFN Ruby: Earned 2,000,000 credits (2,080,358)PSA Jade: Earned 10,000,000 credits (10,863,835)
Message 19437 - Posted: 2 Dec 2009 | 2:50:17 UTC

Thanks for the in-depth answer.

As far as the questions for me, I'm using 64 bit Linux, Genefer 2.2.0 standard (compiled on my machine by me) and one of the recent numbers is 1698566^32768+1.


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FUCK THIS PROJECT AND THEIR COMMIE BULLSHIT POLITICS

Message boards : Project Staging Area : GFN Errors

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