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Message boards : Sieving : Suspending Factorial and Primorial sieving November 1

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JimBProject donor
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Credit: 974,118,817
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Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,691,081)Cullen LLR Turquoise: Earned 5,000,000 credits (5,031,868)ESP LLR Turquoise: Earned 5,000,000 credits (5,064,082)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (5,038,750)PPS LLR Turquoise: Earned 5,000,000 credits (5,000,220)PSP LLR Turquoise: Earned 5,000,000 credits (7,639,762)SoB LLR Sapphire: Earned 20,000,000 credits (42,604,648)SR5 LLR Jade: Earned 10,000,000 credits (11,829,173)SGS LLR Ruby: Earned 2,000,000 credits (2,070,105)TRP LLR Ruby: Earned 2,000,000 credits (2,291,092)Woodall LLR Turquoise: Earned 5,000,000 credits (5,046,412)321 Sieve Jade: Earned 10,000,000 credits (10,057,614)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,002,919)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,005,451)PPS Sieve Emerald: Earned 50,000,000 credits (52,042,965)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,341,676)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,070,804)AP 26/27 Jade: Earned 10,000,000 credits (10,742,251)GFN Emerald: Earned 50,000,000 credits (50,000,251)PSA Double Gold: Earned 500,000,000 credits (728,547,693)
Message 88479 - Posted: 27 Sep 2015 | 16:55:07 UTC
Last modified: 27 Sep 2015 | 16:57:01 UTC

I've been looking into how well sieved we are for factorial and primorial. While at first glance the optimal sieving point appears to be p=376T for factorial and p=133T for primorial, that's only if we're going to test up to the maximum candidate size. For where we are right now, we're oversieved. In the time it takes to remove a candidate by CPU sieving, one can test 3.27 factorial candidates or 1.64 primorial candidates. By definition, when it takes longer to sieve than to test, it's time to stop sieving.

Being on PRPNet, primorial and factorial testing don't progress very quickly. Since LLR won't work on those types of candidates, PFGW is used. We don't currently use PFGW for BOINC testing and there are no plans to do so. So they're going to stay on PRPNet. Sieving for a candidate size that we might reach in 25+ years doesn't seem to be a good use of processing power right now.

Effective November 1st, no new sieving reservations will be accepted for either factorial or primorial sieving. Sieving will be suspended until such time as it's needed again. Obviously that'll be sooner for primorial as the testing/sieving ratio is smaller.

Feel free to discuss this, but from my point of view it's hard to defend more sieving at this point in time.

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Found 1 prime in the 2018 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,037,982)Cullen LLR Ruby: Earned 2,000,000 credits (2,015,907)ESP LLR Ruby: Earned 2,000,000 credits (2,232,391)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,088,705)PPS LLR Ruby: Earned 2,000,000 credits (2,962,062)PSP LLR Ruby: Earned 2,000,000 credits (2,539,644)SoB LLR Ruby: Earned 2,000,000 credits (2,122,524)SR5 LLR Ruby: Earned 2,000,000 credits (2,238,295)SGS LLR Ruby: Earned 2,000,000 credits (2,501,288)TRP LLR Ruby: Earned 2,000,000 credits (2,125,391)Woodall LLR Ruby: Earned 2,000,000 credits (2,037,732)321 Sieve Turquoise: Earned 5,000,000 credits (5,190,731)Cullen/Woodall Sieve (suspended) Silver: Earned 100,000 credits (207,387)Generalized Cullen/Woodall Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,049,697)PPS Sieve Double Bronze: Earned 100,000,000 credits (100,422,123)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (3,227,972)TRP Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,021,659)AP 26/27 Sapphire: Earned 20,000,000 credits (20,651,644)GFN Emerald: Earned 50,000,000 credits (57,918,585)PSA Sapphire: Earned 20,000,000 credits (43,298,465)
Message 88485 - Posted: 27 Sep 2015 | 22:46:16 UTC - in response to Message 88479.

Good work with the new Manual Sieving system JimB. I'll have to try it soon.

My argument against removing Factorial Prime Sieving is it's one of the few apps for AMD GPUs.
I found the bug that prevents sieve input file from ever being able to work with fsievecl:
http://www.primegrid.com/forum_thread.php?id=1163&nowrap=true#80600

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Credit: 308,912,407
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321 LLR Turquoise: Earned 5,000,000 credits (7,001,858)Cullen LLR Turquoise: Earned 5,000,000 credits (6,975,928)ESP LLR Turquoise: Earned 5,000,000 credits (6,807,917)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (6,855,742)PPS LLR Turquoise: Earned 5,000,000 credits (6,346,543)PSP LLR Turquoise: Earned 5,000,000 credits (6,723,187)SoB LLR Turquoise: Earned 5,000,000 credits (6,390,120)SR5 LLR Turquoise: Earned 5,000,000 credits (6,913,425)SGS LLR Turquoise: Earned 5,000,000 credits (6,613,514)TRP LLR Turquoise: Earned 5,000,000 credits (6,155,477)Woodall LLR Turquoise: Earned 5,000,000 credits (6,857,548)321 Sieve Ruby: Earned 2,000,000 credits (3,090,287)Generalized Cullen/Woodall Sieve (suspended) Jade: Earned 10,000,000 credits (10,037,204)PPS Sieve Jade: Earned 10,000,000 credits (10,305,147)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,000,053)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,030,160)AP 26/27 Jade: Earned 10,000,000 credits (10,253,048)GFN Sapphire: Earned 20,000,000 credits (26,797,188)PSA Double Bronze: Earned 100,000,000 credits (170,758,062)
Message 88487 - Posted: 28 Sep 2015 | 1:12:06 UTC

Uh... if we are already oversieved, why don't we just stop right now? Why wait till Nov?

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 PrimesFound 1 prime in the 2020 Tour de Primes321 LLR Ruby: Earned 2,000,000 credits (2,822,730)Cullen LLR Ruby: Earned 2,000,000 credits (2,005,249)ESP LLR Turquoise: Earned 5,000,000 credits (5,009,577)Generalized Cullen/Woodall LLR Ruby: Earned 2,000,000 credits (2,145,754)PPS LLR Jade: Earned 10,000,000 credits (12,843,762)PSP LLR Turquoise: Earned 5,000,000 credits (5,197,957)SoB LLR Sapphire: Earned 20,000,000 credits (34,291,181)SR5 LLR Jade: Earned 10,000,000 credits (10,004,590)SGS LLR Ruby: Earned 2,000,000 credits (2,276,011)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 (9,403,740)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 (20,114,159)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 Jade: Earned 10,000,000 credits (10,114,260)GFN Emerald: Earned 50,000,000 credits (72,383,585)PSA Jade: Earned 10,000,000 credits (12,404,447)
Message 88488 - Posted: 28 Sep 2015 | 2:06:22 UTC - in response to Message 88487.

Uh... if we are already oversieved, why don't we just stop right now? Why wait till Nov?


From a purely mathematical standpoint, there's no reason. But when we shut down a project, try to give participants a bit of advance notice so they have an opportunity to do some last-minute tasks. That's more important when we're shutting down a project with its own badge, but we just want to give everyone a chance to get some work in before it's shut down.

Also, the decision about where to stop sieving is very much a judgement call, so there's no precise spot where you suddenly go from sieving being useful to sieving being useless. It's very much a continuum rather than a specific point.
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321 LLR Silver: Earned 100,000 credits (291,744)Cullen LLR Silver: Earned 100,000 credits (114,325)PPS LLR Amethyst: Earned 1,000,000 credits (1,305,821)PSP LLR Silver: Earned 100,000 credits (471,688)SoB LLR Silver: Earned 100,000 credits (180,347)SR5 LLR Bronze: Earned 10,000 credits (12,917)SGS LLR Gold: Earned 500,000 credits (582,452)TPS LLR (retired) Bronze: Earned 10,000 credits (45,752)TRP LLR Gold: Earned 500,000 credits (873,512)Woodall LLR Bronze: Earned 10,000 credits (29,709)321 Sieve Gold: Earned 500,000 credits (636,635)Cullen/Woodall Sieve (suspended) Gold: Earned 500,000 credits (917,856)PPS Sieve Ruby: Earned 2,000,000 credits (3,152,709)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Gold: Earned 500,000 credits (504,658)TRP Sieve (suspended) Silver: Earned 100,000 credits (445,828)AP 26/27 Silver: Earned 100,000 credits (204,761)PSA Ruby: Earned 2,000,000 credits (2,740,217)
Message 88492 - Posted: 28 Sep 2015 | 8:33:22 UTC

fpsieve is the last linux cpu target for offline use on primegrid. Apart from that, no hard feelings on my side.
____________

JimBProject donor
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Discovered 1 mega prime321 LLR Ruby: Earned 2,000,000 credits (2,691,081)Cullen LLR Turquoise: Earned 5,000,000 credits (5,031,868)ESP LLR Turquoise: Earned 5,000,000 credits (5,064,082)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (5,038,750)PPS LLR Turquoise: Earned 5,000,000 credits (5,000,220)PSP LLR Turquoise: Earned 5,000,000 credits (7,639,762)SoB LLR Sapphire: Earned 20,000,000 credits (42,604,648)SR5 LLR Jade: Earned 10,000,000 credits (11,829,173)SGS LLR Ruby: Earned 2,000,000 credits (2,070,105)TRP LLR Ruby: Earned 2,000,000 credits (2,291,092)Woodall LLR Turquoise: Earned 5,000,000 credits (5,046,412)321 Sieve Jade: Earned 10,000,000 credits (10,057,614)Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (4,002,919)Generalized Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (20,005,451)PPS Sieve Emerald: Earned 50,000,000 credits (52,042,965)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Ruby: Earned 2,000,000 credits (2,341,676)TRP Sieve (suspended) Ruby: Earned 2,000,000 credits (2,070,804)AP 26/27 Jade: Earned 10,000,000 credits (10,742,251)GFN Emerald: Earned 50,000,000 credits (50,000,251)PSA Double Gold: Earned 500,000,000 credits (728,547,693)
Message 88493 - Posted: 28 Sep 2015 | 8:34:17 UTC - in response to Message 88485.

Roger wrote:
I found the bug that prevents sieve input file from ever being able to work with fsievecl:
http://www.primegrid.com/forum_thread.php?id=1163&nowrap=true#80600

Having fsievecl take a sieve input file is useless. All it does, as far as I know, is to suppress output of factors where the candidate is not in the sieve. It will not speed up the process at all. I'd prefer to have all those factors output, it's not like these are huge files. Every time someone hands in an empty factor file, I have to rerun it here myself to ensure they did it properly. I like having all those extra factors.

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321 LLR Amethyst: Earned 1,000,000 credits (1,057,615)Cullen LLR Gold: Earned 500,000 credits (571,506)ESP LLR Silver: Earned 100,000 credits (185,054)Generalized Cullen/Woodall LLR Silver: Earned 100,000 credits (460,220)PPS LLR Amethyst: Earned 1,000,000 credits (1,154,429)PSP LLR Ruby: Earned 2,000,000 credits (2,190,174)SoB LLR Ruby: Earned 2,000,000 credits (2,201,813)SR5 LLR Silver: Earned 100,000 credits (292,115)SGS LLR Gold: Earned 500,000 credits (747,595)TRP LLR Gold: Earned 500,000 credits (675,047)Woodall LLR Amethyst: Earned 1,000,000 credits (1,210,464)321 Sieve Amethyst: Earned 1,000,000 credits (1,016,453)Cullen/Woodall Sieve (suspended) Sapphire: Earned 20,000,000 credits (25,001,013)Generalized Cullen/Woodall Sieve (suspended) Jade: Earned 10,000,000 credits (16,858,065)PPS Sieve Emerald: Earned 50,000,000 credits (65,684,329)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Sapphire: Earned 20,000,000 credits (21,004,347)TRP Sieve (suspended) Jade: Earned 10,000,000 credits (10,080,762)AP 26/27 Turquoise: Earned 5,000,000 credits (5,177,651)GFN Jade: Earned 10,000,000 credits (10,325,889)PSA Double Silver: Earned 200,000,000 credits (267,901,478)
Message 88494 - Posted: 28 Sep 2015 | 10:55:58 UTC

Well, we all knew that this moment will come. If you say we reach a point when we oversieveing, that is no sense into waste more resources and it's time to shut it down. Thanks for heads up though.

So guys, if this are last weeks of it, maybe we push this numbers up?

I call 10 000G for primorial. :D

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Discovered the World's First base 121 Generalized Woodall prime!!!Eliminated 1 conjecture "k"321 LLR Jade: Earned 10,000,000 credits (17,415,188)Cullen LLR Turquoise: Earned 5,000,000 credits (9,954,005)ESP LLR Turquoise: Earned 5,000,000 credits (8,666,161)Generalized Cullen/Woodall LLR Turquoise: Earned 5,000,000 credits (6,580,724)PPS LLR Sapphire: Earned 20,000,000 credits (24,745,108)PSP LLR Jade: Earned 10,000,000 credits (11,349,641)SoB LLR Sapphire: Earned 20,000,000 credits (20,731,142)SR5 LLR Jade: Earned 10,000,000 credits (10,325,270)SGS LLR Turquoise: Earned 5,000,000 credits (7,398,542)TRP LLR Jade: Earned 10,000,000 credits (18,565,735)Woodall LLR Jade: Earned 10,000,000 credits (12,834,401)321 Sieve Amethyst: Earned 1,000,000 credits (1,571,835)Cullen/Woodall Sieve (suspended) Amethyst: Earned 1,000,000 credits (1,300,282)Generalized Cullen/Woodall Sieve (suspended) Ruby: Earned 2,000,000 credits (2,507,840)PPS Sieve Jade: Earned 10,000,000 credits (14,932,890)Sierpinski (ESP/PSP/SoB) Sieve (suspended) Jade: Earned 10,000,000 credits (10,114,568)TRP Sieve (suspended) Turquoise: Earned 5,000,000 credits (5,917,732)AP 26/27 Ruby: Earned 2,000,000 credits (2,264,111)GFN Emerald: Earned 50,000,000 credits (61,954,241)PSA Emerald: Earned 50,000,000 credits (62,056,274)
Message 88635 - Posted: 2 Oct 2015 | 12:18:23 UTC - in response to Message 88479.

For where we are right now, we're oversieved. In the time it takes to remove a candidate by CPU sieving, one can test 3.27 factorial candidates or 1.64 primorial candidates. By definition, when it takes longer to sieve than to test, it's time to stop sieving.


On Dual E5-2620 (running 12 threads), times are per 1 thread:
fpsieve - 1factor/24hrs
pfgw64 - 1test/20hrs

Message boards : Sieving : Suspending Factorial and Primorial sieving November 1

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