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2008-07-20, 10:33   #56
KEP

May 2005

2×3×7×23 Posts

Quote:
 Originally Posted by em99010pepe It's BOINC guilt because the people who run it don't understand nothing about what they are doing. They don't know they need to have a stable machine to test numbers, they just run BOINC for the stats, to help their teams climb in the stats. It's intrinsic. Of course with the amount of CPU power they have they can easily doublecheck 3, 4, 5 times but that's ridiculous. By 3 or 4 clicks you can easily change BOINC projects even when you are an ignorant on the matter. That should not be like that. People should understand what they are doing, study a little bit of LLR and prime stuff. Do you want to know the lastes problem of BOINC? It's possible to hijack the teams...true, check here.

Kenneth!

 2008-07-24, 08:03 #57 gd_barnes     May 2007 Kansas; USA 27×34 Posts 9675*256^41822-1 is prime 7788*256^42163-1 is prime Riesel base 256 is currently at n=44K; still going to n=75K. 40 k's are still remaining. One month ago and the larger prime would have been top-5000. 3 months ago and they both would have been top-5000. I should have started sooner. lol Gary Last fiddled with by gd_barnes on 2008-07-24 at 08:04
 2008-08-13, 05:09 #58 gd_barnes     May 2007 Kansas; USA 242008 Posts Riesel base 256 is now complete to n=50K. 2 primes for n=40K-50K previously reported. Continuing on to n=75K after pausing for 2-3 weeks to continue Sierp base 12 from n=167K.
2008-09-06, 04:31   #59
gd_barnes

May 2007
Kansas; USA

27×34 Posts

Quote:
 Originally Posted by gd_barnes Riesel base 256 is now complete to n=50K. 2 primes for n=40K-50K previously reported. Continuing on to n=75K after pausing for 2-3 weeks to continue Sierp base 12 from n=167K.

I've now restarted Riesel base 256 from n=50K...still going to n=75K. With some extra fire power now, I'll keep on running base 12 and 256 and possibly reserve some base 16 stuff within the next few weeks.

Gary

 2008-09-10, 23:00 #60 gd_barnes     May 2007 Kansas; USA 27×34 Posts Riesel base 256 is now at n=54K. No new primes to report.
2008-09-22, 01:17   #61
gd_barnes

May 2007
Kansas; USA

27×34 Posts

Quote:
 Originally Posted by KEP I've no idea exactly how long it is going to take, regarding the Sierp. base 19 but I guess around 2 weeks from now. Regarding Sierp. base 252 it is most likely only 2 days of work left on the Quad, after that it will most likely have progressed (if not finished) very far with the remaining ranges for Riesel base 3 k<=500M. KEP!
Sierp base 252 for n=51K-100K is FAR more than 2 days work on a quad (i.e. 8 CPU days). What is your testing time per candidate at n=51K and how many candidates are remaining to be tested?

Keep in mind that a test at n=100K will take FOUR times as long as a test at n=50K.

If you give me the above info., I can, in effect, use the equivalent of compound interest formulas to give you a fairly accurate estimate of how long base 252 should take for n=51K-100K.

Gary

Last fiddled with by gd_barnes on 2010-05-16 at 08:32 Reason: remove base <= 250

2008-09-22, 05:34   #62
KEP

May 2005

2·3·7·23 Posts

Quote:
 Originally Posted by gd_barnes OK, for now I'll reserve sieving only to you on k=100M-200M for Sierp base 3. Sierp base 252 for n=51K-100K is FAR more than 2 days work on a quad (i.e. 8 CPU days). What is your testing time per candidate at n=51K and how many candidates are remaining to be tested? Keep in mind that a test at n=100K will take FOUR times as long as a test at n=50K. If you give me the above info., I can, in effect, use the equivalent of compound interest formulas to give you a fairly accurate estimate of how long base 252 should take for n=51K-100K. Gary
At n=52000 it takes 1045 sec per test. A total of ~2200 tests is left to test.

KEP

2008-09-22, 05:53   #63
gd_barnes

May 2007
Kansas; USA

27·34 Posts

Quote:
 Originally Posted by KEP At n=52000 it takes 1045 sec per test. A total of ~2200 tests is left to test. KEP
Expected time is 5.074M CPU secs. or ~58.7 CPU days. Running all 4 cores of a quad 24 hours a day 7 days a week will take ~14.7 calendar days.

A bit longer than 2 days.

Even if all tests took the same amount of time, it would be 1045*2200/86400 = 26.6 CPU days or 6.65 days on all 4 cores of a quad. But clearly all tests don't take the same amount of time.

To get to the original calculation, I assumed a constant rate of change in the n-values being tested and a constant SQUARED rate of change in the time each test would take.

So if n=52K takes 1045 secs., then n=52K*2=104K would take 1045*4=4180 secs. Also:
n = 52K * sqrt(2) = 73.5K would take 1045*2=2090 secs.

Obviously LLR time goes up in fits and spurts with fftlen changes so this can only be said to be a rough estimate. But it should be in the ball park since in the long run, LLR times varies with the square of the exponent.

Gary

Last fiddled with by gd_barnes on 2008-09-22 at 06:00

 2008-10-20, 18:01 #64 KEP Quasi Admin Thing     May 2005 96610 Posts Reserving Riesel base 255 for a future "Riesel base 255 attack". I expect it to overtake the "Riesel base 3 attack" website. I've already begun some initial testings and it seems very prime dense, so I will have no problem running this conjecture up to PG level, if Rytis wanna help out. Expect by no terms any further work from me beyound k<=500M to n<=25K for Riesel base 3 conjecture. It turns out to be to much of a handfull for me to handle, I still like the conjectures, so therefor I'm doing the initial preparations to launch a fullscale attack on the Riesel base 255 conjecture Hope no one mind. Also I'm gonna need something to keep my computers busy as they slowly runs out of work for previously reservations Regards KEP!
2008-10-20, 21:32   #65
gd_barnes

May 2007
Kansas; USA

27×34 Posts

Quote:
 Originally Posted by KEP Reserving Riesel base 255 for a future "Riesel base 255 attack". I expect it to overtake the "Riesel base 3 attack" website. I've already begun some initial testings and it seems very prime dense, so I will have no problem running this conjecture up to PG level, if Rytis wanna help out. Expect by no terms any further work from me beyound k<=500M to n<=25K for Riesel base 3 conjecture. It turns out to be to much of a handfull for me to handle, I still like the conjectures, so therefor I'm doing the initial preparations to launch a fullscale attack on the Riesel base 255 conjecture Hope no one mind. Also I'm gonna need something to keep my computers busy as they slowly runs out of work for previously reservations Regards KEP!
This is a multi CPU-year effort to test such a high base with a high conjecture up to PrimeGrid level, regardless of how prime the base is. I'm assuming that PrimeGrid level would be defined as tests that would yield top-5000 primes. For base 255, that would be at n=42K-43K now; higher when you get up that far later.

Didn't you test Sierp base 255 up to n=2500? Do you remember how long it took for you to get that tested? Now, you're going to test the Riesel side with a conjecture that is twice as high?

You are correct, it seems that all bases (b) where b=2^q-1, i.e. 3, 7, 15, 31, etc. are prime dense but because they are so primeful, they also have very high conjectures vs. their neighbor bases, which makes them more difficult to prove then a large majority of other bases.

I have 3 alternatives for you if you want to test base 255 up to PrimeGrid level in a reasonable amount of time:
(a) Do Sierp base 255 instead. It's already at n=2500 and the conjecture is half as high.
(b) Start a new thread here at CRUS and attempt to get some help testing Riesel base 255.

Even if you do (a), you'll likely still need to enlist some help here at some point.

Gary

2008-10-21, 16:42   #66
KEP

May 2005

3C616 Posts

Quote:
 Originally Posted by gd_barnes This is a multi CPU-year effort to test such a high base with a high conjecture up to PrimeGrid level, regardless of how prime the base is. I'm assuming that PrimeGrid level would be defined as tests that would yield top-5000 primes. For base 255, that would be at n=42K-43K now; higher when you get up that far later. Didn't you test Sierp base 255 up to n=2500? Do you remember how long it took for you to get that tested? Now, you're going to test the Riesel side with a conjecture that is twice as high? You are correct, it seems that all bases (b) where b=2^q-1, i.e. 3, 7, 15, 31, etc. are prime dense but because they are so primeful, they also have very high conjectures vs. their neighbor bases, which makes them more difficult to prove then a large majority of other bases. I have 3 alternatives for you if you want to test base 255 up to PrimeGrid level in a reasonable amount of time: (a) Do Sierp base 255 instead. It's already at n=2500 and the conjecture is half as high. (b) Start a new thread here at CRUS and attempt to get some help testing Riesel base 255. (c) Buy several new quads. (lol) Even if you do (a), you'll likely still need to enlist some help here at some point. Gary
I'm not going to reserve any of these bases anyway. Even taking it to n<=25000 is more work than I really feels like doing anymore... so I'm wrapping my final works (8 weeks to go at least) amd then I'll decide what (if any) to reserve when that time comes. Sorry for yabbing again, but I made a mistake by simply forgetting how many more weeks of work I've left. Hope you understand and accept my appology... Anyway base 19 Sierp is going to be wrapped somewhere close to next weekend (maybe already the coming weekend)

Take care everyone and happy crunching

KEP

Last fiddled with by KEP on 2008-10-21 at 17:37 Reason: Corrected a bad reservation before it got reserved

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