mersenneforum.org Sieving Drive all base 2/4 k's worked by CRUS
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 2013-09-20, 01:20 #1 gd_barnes     May 2007 Kansas; USA 1052010 Posts Sieving Drive all base 2/4 k's worked by CRUS This is a sieving drive for all 16 k's for both sides of bases 2 & 4 that are currently being worked on by CRUS. Included in the drive are 11 k's for base 2 even & odd n, 4 k's for base 2 even k, and 1 k for base 4. (The remainder of base 4 k's are effectively included in base 2 even/odd n or are being worked by other projects.) I have spent the last several weeks sieving all 17 k's for the entire range of n=1M to 16777216 to P=100T as an extension to Jean Penne's sieve for the 12 k's for base 2 even/odd n and as a starting point for this effort. The file contains 3 k's that have effectively already been sieved to a deep depth but for a smaller n-range by PrimeGrid. I am leaving them in there because we are sieving a much wider n-range and the cost to keep them in there is minimal. The file also contains all n=1M-2M, which we have already tested. I am leaving the range in there because we will be doing doublechecks in the future and the cost to keep it in there is minimal. As we progress, we will determine testing break off points based on sieving and testing speed. Testing will be done in a new team drive. This will allow us to at least somewhat bridge the gap between our base 2/4 search depth and other project's depth. Like before, sr2sieve is what we will use. It is recommended that you run 64-bit sr2sieve on a 64-bit machine. Let us know if you need the executable or more detailed instructions on using it. Here is an example of the command to execute at the command prompt: sr2sieve -p 115e12 -P 125e12 -i sieve-riesel-sierp-even-odd-k-n.txt The above would be if you were sieving P=115T-125T. The file is listed after the "-i" command and is the actual file name that is posted in a link below. Feel free to name it something shorter if you want or use the "srwork" older convention where you don't have to specify a file name. When complete, you should have a factors.txt file. Just post the file here in this thread or if it is too big, please Email the file to me at: gbarnes017 at gmail dot com A P=1T range should take ~5-6 CPU days on a modern 64-bit machine. Please reserve ranges in multiples of P=1T and plan to reserve no more than ~10 days of work at a time. When making reservations, please post your estimated completion date. This can be seen in sr2sieve about one minute after you start your sieve. Here is a link to the latest sieve file: http://www.noprimeleftbehind.net/cru...en-odd-k-n.zip All factors up to P=760T have been removed. We will remove additional factors as the drive progresses to slightly speed up sieving. Reservations: Code:  P-range reserved by status est. completion date 100T-119T Lennart complete 119T-129T KEP complete 129T-140T Lennart complete 140T-144T KEP complete 144T-178T Lennart complete 178T-188T KEP complete 188T-410T Lennart complete 410T-415T TheCount complete 415T-420T Lennart complete 420T-507T gd_barnes complete 507T-580T Lennart complete 580T-582T mdettweiler complete 582T-760T Lennart complete All help is greatly appreciated as we attempt to bring our bases 2 & 4 up to a level near other project's search depth! Thank you, Gary Last fiddled with by gd_barnes on 2014-11-29 at 07:54 Reason: status update
 2013-09-20, 05:06 #2 c10ck3r     Aug 2010 Kansas 22316 Posts Yea, so, stupid question time...why are "we" (not myself, the 5T range would take almost a month on my laptop) including such small n values in this sieve. I have it on good authority (read: I ran LLR) that there are no primes for any of the n values below 25k, and likely much higher than that. Is there any merit for including these in a sieve, or could they be, say, removed by concurrent LLR testing? Someone should really teach me how to read. Sidebar: New main point: For anyone that's wondering on quick stats before they try it, running sr2sieve on 1 core of my i5-2450M @ 2.50 GHz laptop, the 5T range from 195-200T would take until Oct 17. There are abt. 1.3M candidates in the sieve file, and the above range has ~1063 expected factors. Last fiddled with by c10ck3r on 2013-09-20 at 05:08
2013-09-20, 06:31   #3
gd_barnes

May 2007
Kansas; USA

23·5·263 Posts

Quote:
 Originally Posted by c10ck3r Yea, so, stupid question time...why are "we" (not myself, the 5T range would take almost a month on my laptop) including such small n values in this sieve. I have it on good authority (read: I ran LLR) that there are no primes for any of the n values below 25k, and likely much higher than that. Is there any merit for including these in a sieve, or could they be, say, removed by concurrent LLR testing? Someone should really teach me how to read. Sidebar: New main point: For anyone that's wondering on quick stats before they try it, running sr2sieve on 1 core of my i5-2450M @ 2.50 GHz laptop, the 5T range from 195-200T would take until Oct 17. There are abt. 1.3M candidates in the sieve file, and the above range has ~1063 expected factors.
I would recommend at least 4 cores for sieving 5T on this. It took me a little over 3 weeks on 24 cores (2.4-2.6 Ghz) to sieve 100T (70+ CPU weeks). Yep, it's a HUGE effort but it will pay off in the long run. On my one more modern 2.9 Ghz machine, it was processing about P=2.2M per second. That's about P=190G per day or about P=1T in 5 days. So you can figure on ~25 CPU days to sieve P=5T. 4 cores could do it in < 1 week.

Gary

Last fiddled with by gd_barnes on 2013-09-20 at 06:36

 2013-09-20, 18:20 #4 Lennart     "Lennart" Jun 2007 25×5×7 Posts Reserving 100T-110T Lennart
 2013-09-20, 19:40 #5 Lennart     "Lennart" Jun 2007 25×5×7 Posts Reserving 110T-113T Lennart
 2013-09-20, 19:55 #6 Lennart     "Lennart" Jun 2007 46016 Posts Reserving 113T-119T Lennart
 2013-09-20, 20:43 #7 gd_barnes     May 2007 Kansas; USA 23×5×263 Posts After some thinking about c10ck3r's comments, I've decided that it's OK to make reservations as small as P=1T to allow our smaller searchers to participate in the sieving. I'd still like to ask that reservations be completed within ~10 days so that we can periodically remove a contiguous set of factors from the file for future sieving efficiency. By my calculations, a P=1T range should take ~5 days on one core of a modern machine.
2013-09-25, 01:11   #8
Lennart

"Lennart"
Jun 2007

100011000002 Posts

110T-119T complete

Lennart
Attached Files
 crussieve.zip (44.4 KB, 201 views)

2013-09-30, 02:18   #9
Lennart

"Lennart"
Jun 2007

112010 Posts

100T-110T complete

Sorry I missed those.

Lennart
Attached Files
 crussieve100T-110T.zip (52.7 KB, 238 views)

 2013-09-30, 04:58 #10 gd_barnes     May 2007 Kansas; USA 291816 Posts Thanks Lennart. A new file has been posted with all factors up to P=119T removed.
 2013-10-05, 16:31 #11 KEP Quasi Admin Thing     May 2005 967 Posts Reserving: 119T-121T ETA is ~9.5 Days

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