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Old 2021-04-21, 17:35   #397
axn
 
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Quote:
Originally Posted by chalsall View Post
OK. Thanks a lot! The first five are running now.

Seems like there's still some Primenet work to do though...
Quote:
Originally Posted by Prime95 View Post
Primenet accepts P+1 results, but does not recognize/coordinate P+1 assignments.
Ok, I guess we need to add N/A at the beginning to avoid assignment registration attempt, right? (or UsePrimenet=0 / manually report)

Last fiddled with by axn on 2021-04-21 at 17:35
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Old 2021-04-21, 18:00   #398
James Heinrich
 
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This is crude, but I have created a placeholder page to list what known P+1 efforts have been recorded:
https://www.mersenne.ca/pplus1.php

Note of course that my data will always be up to 24h out of date (synch'ed just after midnight UTC).
Will get a better report on mersenne.org (at least if George can email me where to find the P+1 data).
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Old 2021-04-21, 18:51   #399
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Quote:
Originally Posted by Prime95 View Post
Are you out to lunch? Somewhat. P+1 will find different factors than P-1, but is vastly inferior to P-1. The loss of the "free 2*p" in B1/B2 smoothness for Mersenne numbers where factors are known to be of the form 2*k*p+1 is huge. Add on to that the 50% chance that P+1 won't find the factor even if it is B1/B2 smooth. Depending on TF levels, you're probably looking at 100-300 P+1 runs to find a single factor.

I fear that for exponents above 20M you're better off extending P-1 bounds rather than doing P+1. As you gather data, you may prove my fear wrong.
Yes seems P-1 is still better. Though the odds of finding a factor per assignment is dropping in these stubborn ranges its still in the 50-80 range.
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Old 2021-04-21, 19:02   #400
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Quote:
Originally Posted by Prime95 View Post
Primenet accepts P+1 results, but does not recognize/coordinate P+1 assignments.
OK... Here are the log entries from my fastest machine for those who understand the maths behind all this. The probability percentage is indeed low... This is for 42600139.

Code:
[Main thread Apr 21 13:11] Mersenne number primality test program version 30.6
[Main thread Apr 21 13:11] Optimizing for CPU architecture: Core i3/i5/i7, L2 cache size: 6x256 KB, L3 cache size: 12 MB
[Main thread Apr 21 13:11] Starting worker.
[Comm thread Apr 21 13:11] Updating computer information on the server
[Work thread Apr 21 13:11] Worker starting
[Work thread Apr 21 13:11] Setting affinity to run worker on CPU core #1
[Work thread Apr 21 13:11] 
[Work thread Apr 21 13:11] P+1 on M42600139 with B1=400000, B2=TBD
[Work thread Apr 21 13:12] Setting affinity to run helper thread 5 on CPU core #6
[Work thread Apr 21 13:12] Setting affinity to run helper thread 4 on CPU core #5
[Work thread Apr 21 13:12] Setting affinity to run helper thread 3 on CPU core #4
[Work thread Apr 21 13:12] Using FMA3 FFT length 2304K, Pass1=384, Pass2=6K, clm=2, 6 threads
[Work thread Apr 21 13:12] Setting affinity to run helper thread 2 on CPU core #3
[Work thread Apr 21 13:12] Setting affinity to run helper thread 1 on CPU core #2
[Work thread Apr 21 13:12] M42600139 stage 1 is 1.00% complete. Time: 42.031 sec.
[Work thread Apr 21 13:13] M42600139 stage 1 is 2.16% complete. Time: 42.031 sec.
[Work thread Apr 21 13:14] M42600139 stage 1 is 3.31% complete. Time: 42.133 sec.


[Work thread Apr 21 14:11] M42600139 stage 1 is 96.63% complete. Time: 42.167 sec.
[Work thread Apr 21 14:11] M42600139 stage 1 is 97.80% complete. Time: 42.217 sec.
[Work thread Apr 21 14:12] M42600139 stage 1 is 98.90% complete. Time: 42.254 sec.
[Work thread Apr 21 14:13] M42600139 stage 1 complete. 1020144 transforms. Time: 2152.052 sec.
[Work thread Apr 21 14:13] Stage 1 GCD complete. Time: 8.352 sec.
[Work thread Apr 21 14:13] With trial factoring done to 2^75, optimal B2 is 42*B1 = 16800000.
[Work thread Apr 21 14:13] Chance of a new factor assuming no ECM has been done is 0.274%
[Work thread Apr 21 14:13] D: 630, relative primes: 1439, stage 2 primes: 1045406, pair%=94.24
[Work thread Apr 21 14:13] Using 26374MB of memory.
[Work thread Apr 21 14:13] Stage 2 init complete. 4243 transforms. Time: 13.237 sec.
[Work thread Apr 21 14:14] M42600139 stage 2 is 1.67% complete. Time: 35.680 sec.
[Work thread Apr 21 14:14] M42600139 stage 2 is 3.35% complete. Time: 35.685 sec.
[Work thread Apr 21 14:15] M42600139 stage 2 is 5.05% complete. Time: 35.688 sec.


[Work thread Apr 21 14:46] M42600139 stage 2 is 95.36% complete. Time: 35.681 sec.
[Work thread Apr 21 14:47] M42600139 stage 2 is 97.08% complete. Time: 35.682 sec.
[Work thread Apr 21 14:47] M42600139 stage 2 is 98.79% complete. Time: 35.678 sec.
[Work thread Apr 21 14:48] M42600139 stage 2 complete. 1154122 transforms. Time: 2060.598 sec.
[Work thread Apr 21 14:48] Stage 2 GCD complete. Time: 8.313 sec.
[Work thread Apr 21 14:48] M42600139 completed P+1, B1=400000, B2=16800000, Wi8: 4F3C1C20
[Comm thread Apr 21 14:48] Sending result to server: UID: wabbit/rdt1, M42600139 completed P+1, B1=400000, B2=16800000, Wi8: 4F3C1C20
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Old 2021-04-21, 19:17   #401
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So, 1H30 for a 0.274% chance of finding a factor?
Should one run a normal P+1 (3 tries) , 5 H for a less than a percent chance of finding a factor?

It is indeed very low.
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Old 2021-04-21, 19:29   #402
petrw1
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And unless P+1 takes into account how much P-1 has already been done it will be lower yet.
Or is prior P-1 not relevant to the success rate if P+1.

Last fiddled with by petrw1 on 2021-04-21 at 19:29
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Old 2021-04-21, 19:33   #403
Prime95
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Quote:
Originally Posted by petrw1 View Post
And unless P+1 takes into account how much P-1 has already been done it will be lower yet.
Or is prior P-1 not relevant to the success rate if P+1.
P-1 and P+1 search space is almost completely independent.
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Old 2021-04-21, 19:35   #404
Prime95
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Quote:
Originally Posted by firejuggler View Post
So, 1H30 for a 0.274% chance of finding a factor?
Should one run a normal P+1 (3 tries) , 5 H for a less than a percent chance of finding a factor?

It is indeed very low.
You'll get better chances with smaller exponents -- less TF has been done. I was getting 1+% estimates in the 4.7M range with B1=1000000.
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Old 2021-04-21, 20:00   #405
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Quote:
Originally Posted by Prime95 View Post
I suggest picking one exponent and try a B1/B2 combination -- plus specify the TF bit level. Start prime95 and it will tell you the chance of finding a factor. Abort, select different B1/B2, run prime95 and look at the chance of finding a factor. Repeat until you have a decent idea as to how bounds correlate with probability.
You also need to clear the Pplus1BestB2 option to get the quick probability at startup.

Now that I've fixed the crash bug reading stage 2 save file, I'll gather some of this data and post it here.

Last fiddled with by Prime95 on 2021-04-21 at 20:41
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Old 2021-04-21, 20:11   #406
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31M expo, TF'ed to 2^75

Code:
[Apr 21 16:05] P+1 on M31500457 with B1=250000, B2=5000000
[Apr 21 16:05] Chance of finding a factor assuming no ECM has been done is an estimated 0.16%

[Apr 21 16:06] P+1 on M31500457 with B1=250000, B2=10000000
[Apr 21 16:06] Chance of finding a factor assuming no ECM has been done is an estimated 0.194%

[Apr 21 16:06] P+1 on M31500457 with B1=250000, B2=20000000
[Apr 21 16:06] Chance of finding a factor assuming no ECM has been done is an estimated 0.232%

[Apr 21 16:06] P+1 on M31500457 with B1=500000, B2=10000000
[Apr 21 16:06] Chance of finding a factor assuming no ECM has been done is an estimated 0.261%

[Apr 21 16:07] P+1 on M31500457 with B1=500000, B2=20000000
[Apr 21 16:07] Chance of finding a factor assuming no ECM has been done is an estimated 0.313%

[Apr 21 16:07] P+1 on M31500457 with B1=500000, B2=40000000
[Apr 21 16:07] Chance of finding a factor assuming no ECM has been done is an estimated 0.37%

[Apr 21 16:08] P+1 on M31500457 with B1=1000000, B2=20000000
[Apr 21 16:08] Chance of finding a factor assuming no ECM has been done is an estimated 0.399%

[Apr 21 16:08] P+1 on M31500457 with B1=1000000, B2=40000000
[Apr 21 16:08] Chance of finding a factor assuming no ECM has been done is an estimated 0.475%

[Apr 21 16:08] P+1 on M31500457 with B1=1000000, B2=80000000
[Apr 21 16:08] Chance of finding a factor assuming no ECM has been done is an estimated 0.556%
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Old 2021-04-21, 20:12   #407
chalsall
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Default Initial emprical data from five runs...

These next four runs (with different B1s as given by axn) were run on GCE 8 vcore instances with 30G of RAM available to them:

Code:
[Work thread Apr 21 17:19] P+1 on M42600221 with B1=500000, B2=TBD
[Work thread Apr 21 17:19] Setting affinity to run helper thread 2 on CPU core #3
[Work thread Apr 21 17:19] Using AVX-512 FFT length 2240K, Pass1=128, Pass2=17920, clm=4, 4 threads
[Work thread Apr 21 17:19] Setting affinity to run helper thread 3 on CPU core #4
[Work thread Apr 21 17:19] Setting affinity to run helper thread 1 on CPU core #2
[Work thread Apr 21 17:20] M42600221 stage 1 is 0.78% complete. Time: 35.714 sec.

[Work thread Apr 21 18:28] M42600221 stage 1 complete. 2177465 transforms. Time: 4116.695 sec.
[Work thread Apr 21 18:28] Stage 1 GCD complete. Time: 11.694 sec.
[Work thread Apr 21 18:28] With trial factoring done to 2^75, optimal B2 is 44*B1 = 22000000.
[Work thread Apr 21 18:28] Chance of a new factor assuming no ECM has been done is 0.321%
[Work thread Apr 21 18:28] D: 630, relative primes: 1683, stage 2 primes: 1347723, pair%=95.30
[Work thread Apr 21 18:28] Using 29991MB of memory.
[Work thread Apr 21 18:28] Stage 2 init complete. 4961 transforms. Time: 21.750 sec.
[Work thread Apr 21 18:29] M42600221 stage 2 is 1.30% complete. Time: 33.963 sec.

[Work thread Apr 21 19:08] M42600221 stage 2 is 99.03% complete. Time: 32.330 sec.
[Work thread Apr 21 19:09] M42600221 stage 2 complete. 1474580 transforms. Time: 2416.992 sec.
[Work thread Apr 21 19:09] Stage 2 GCD complete. Time: 11.498 sec.
[Work thread Apr 21 19:09] M42600221 completed P+1, B1=500000, B2=22000000, Wi8: 4F793D3E
[Comm thread Apr 21 19:09] Sending result to server: UID: ***/GCE_2, M42600221 completed P+1, B1=500000, B2=22000000, Wi8: 4F793D3E



[Work thread Apr 21 17:19] P+1 on M42600289 with B1=600000, B2=TBD
[Work thread Apr 21 17:20] M42600289 stage 1 is 0.64% complete. Time: 36.778 sec.

[Work thread Apr 21 18:40] M42600289 stage 1 is 99.56% complete. Time: 37.153 sec.
[Work thread Apr 21 18:40] M42600289 stage 1 complete. 2614375 transforms. Time: 4828.669 sec.
[Work thread Apr 21 18:40] Stage 1 GCD complete. Time: 11.328 sec.
[Work thread Apr 21 18:40] With trial factoring done to 2^75, optimal B2 is 46*B1 = 27600000.
[Work thread Apr 21 18:40] Chance of a new factor assuming no ECM has been done is 0.364%
[Work thread Apr 21 18:40] D: 630, relative primes: 1683, stage 2 primes: 1669036, pair%=95.27
[Work thread Apr 21 18:40] Using 29992MB of memory.
[Work thread Apr 21 18:40] Stage 2 init complete. 4961 transforms. Time: 20.257 sec.
[Work thread Apr 21 18:41] M42600289 stage 2 is 1.05% complete. Time: 31.121 sec.

[Work thread Apr 21 19:28] M42600289 stage 2 is 99.59% complete. Time: 31.242 sec.
[Work thread Apr 21 19:28] M42600289 stage 2 complete. 1827707 transforms. Time: 2857.538 sec.
[Work thread Apr 21 19:28] Stage 2 GCD complete. Time: 11.302 sec.
[Work thread Apr 21 19:28] M42600289 completed P+1, B1=600000, B2=27600000, Wi8: 4FBB23DF
[Comm thread Apr 21 19:28] Sending result to server: UID: ***/GCE_1, M42600289 completed P+1, B1=600000, B2=27600000, Wi8: 4FBB23DF



[Work thread Apr 21 17:20] P+1 on M42600367 with B1=700000, B2=TBD
[Work thread Apr 21 17:20] M42600367 stage 1 is 0.53% complete. Time: 36.484 sec.

[Work thread Apr 21 18:53] M42600367 stage 1 is 99.83% complete. Time: 36.878 sec.
[Work thread Apr 21 18:53] M42600367 stage 1 complete. 3048479 transforms. Time: 5579.300 sec.
[Work thread Apr 21 18:53] Stage 1 GCD complete. Time: 11.253 sec.
[Work thread Apr 21 18:53] With trial factoring done to 2^75, optimal B2 is 47*B1 = 32900000.
[Work thread Apr 21 18:53] Chance of a new factor assuming no ECM has been done is 0.401%
[Work thread Apr 21 18:53] D: 630, relative primes: 1683, stage 2 primes: 1969321, pair%=95.19
[Work thread Apr 21 18:53] Using 29994MB of memory.
[Work thread Apr 21 18:54] M42600367 stage 2 is 0.89% complete. Time: 31.187 sec.

[Work thread Apr 21 19:49] M42600367 stage 2 is 99.13% complete. Time: 31.257 sec.
[Work thread Apr 21 19:50] M42600367 stage 2 complete. 2158931 transforms. Time: 3377.253 sec.
[Work thread Apr 21 19:50] Stage 2 GCD complete. Time: 11.398 sec.
[Work thread Apr 21 19:50] M42600367 completed P+1, B1=700000, B2=32900000, Wi8: 4C34DDA9
[Comm thread Apr 21 19:50] Sending result to server: UID: ***/GCE_3, M42600367 completed P+1, B1=700000, B2=32900000, Wi8: 4C34DDA9



[Work thread Apr 21 17:20] P+1 on M42600379 with B1=800000, B2=TBD
[Work thread Apr 21 17:21] M42600379 stage 1 is 0.46% complete. Time: 34.118 sec.

[Work thread Apr 21 18:59] M42600379 stage 1 is 99.95% complete. Time: 34.114 sec.
[Work thread Apr 21 18:59] M42600379 stage 1 complete. 3486053 transforms. Time: 5931.664 sec.
[Work thread Apr 21 18:59] Stage 1 GCD complete. Time: 10.011 sec.
[Work thread Apr 21 18:59] With trial factoring done to 2^75, optimal B2 is 48*B1 = 38400000.
[Work thread Apr 21 18:59] Chance of a new factor assuming no ECM has been done is 0.437%
[Work thread Apr 21 18:59] D: 630, relative primes: 1683, stage 2 primes: 2278054, pair%=95.13
[Work thread Apr 21 18:59] Using 29996MB of memory.
[Work thread Apr 21 18:59] Stage 2 init complete. 4963 transforms. Time: 18.917 sec.
[Work thread Apr 21 19:00] M42600379 stage 2 is 0.77% complete. Time: 28.566 sec.

[Work thread Apr 21 19:58] M42600379 stage 2 is 99.22% complete. Time: 28.586 sec.
[Work thread Apr 21 19:59] M42600379 stage 2 complete. 2499826 transforms. Time: 3571.213 sec.
[Work thread Apr 21 19:59] Stage 2 GCD complete. Time: 9.984 sec.
[Work thread Apr 21 19:59] M42600379 completed P+1, B1=800000, B2=38400000, Wi8: 4C474AA4
[Comm thread Apr 21 19:59] Sending result to server: UID: xxx/GCE_4, M42600379 completed P+1, B1=800000, B2=38400000, Wi8: 4C474AA4
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