mersenneforum.org 12+256 matrix job
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 2009-08-16, 12:17 #1 fivemack (loop (#_fork))     Feb 2006 Cambridge, England 645410 Posts 12+256 matrix job I have found 35 dependencies, but then the network card on the machine I found them on failed so it will be a little while before I can get the square root done
2009-08-16, 13:56   #2
bdodson

Jun 2005
lehigh.edu

20008 Posts

Quote:
 Originally Posted by fivemack I have found 35 dependencies, but then the network card on the machine I found them on failed so it will be a little while before I can get the square root done
the matrix finished. I was wondering whether you're
impatient yet for gnfs data? Sieving for Serge's
2, 2086M is just about done, so I would switch to
our c163 if you wanted more data soon. -Bruce

 2009-08-16, 19:39 #3 fivemack (loop (#_fork))     Feb 2006 Cambridge, England 2×7×461 Posts It turns out that unplugging the computer, plugging it in again, turning it on (at which point it fails to start booting), turning it off again and turning it on for a second time will sometimes make the network interface reappear. Code: Fri Jun 26 00:58:30 2009 memory use: 7421.1 MB Tue Aug 11 19:38:36 2009 lanczos halted after 387759 iterations (dim = 24519655) Tue Aug 11 19:39:17 2009 recovered 35 nontrivial dependencies Tue Aug 11 19:39:18 2009 BLanczosTime: 4045839 Tue Aug 11 19:39:18 2009 elapsed time 1123:50:42 ... Sun Aug 16 20:34:00 2009 commencing square root phase Sun Aug 16 20:34:00 2009 reading relations for dependency 1 Sun Aug 16 20:34:10 2009 read 12262248 cycles Sun Aug 16 20:34:29 2009 cycles contain 38132421 unique relations 6783 nfsslave 20 0 4513m 3.9g 1028 R 47 33.4 3:49.06 msieve 6783 nfsslave 20 0 5929m 5.7g 1028 R 55 48.6 7:31.56 msieve The square roots are clearly not trivial jobs; I don't know whether it's more realistic to expect factors in 12 hours or in 36; I suspect that, as in the other 32-bit-each-side example, there are no quadratic characters in play and so a lot of the square roots will fail. Last fiddled with by fivemack on 2009-08-16 at 19:44
2009-08-17, 10:12   #4
fivemack
(loop (#_fork))

Feb 2006
Cambridge, England

2·7·461 Posts
And it's done

Code:
Sun Aug 16 20:49:14 2009  multiplying 30857386 relations
Sun Aug 16 22:23:43 2009  multiply complete, coefficients have about 841.60 million bits
Sun Aug 16 22:23:52 2009  initial square root is modulo 35517907
Mon Aug 17 01:24:32 2009  sqrtTime: 17432
Mon Aug 17 01:24:32 2009  prp96 factor: 452271654045095376354829024468620655107168044537189917947981878284544891082485331470888529210881
Mon Aug 17 01:24:32 2009  prp132 factor: 293351100534073339320273736685554040546989773558978742766077630132017865996601983557083266543920963624936810354879103450020778081793
Mon Aug 17 01:24:32 2009  elapsed time 04:50:34
Full processing log attached; note that I did a lot of duplicate-counting runs and several matrix-making runs before deciding that I had a small enough matrix. There were over 675 million input relations for the final reasonable-sized matrix (and 433 million unique) even with substantial pre-uniquing at Dodson's end, I would say the duplication rate means that this was about as large a number as you'd want to use siever 15e on.
Attached Files
 12+256.mlog.bz2 (99.9 KB, 391 views)

Last fiddled with by fivemack on 2009-08-17 at 10:13

 2009-08-17, 10:49 #5 Andi_HB     Mar 2007 Germany 23×3×11 Posts Wow ! Over 400 Million unique relations are impressive. Congratulation to this big job.
 2009-08-17, 14:01 #6 jasonp Tribal Bullet     Oct 2004 32·5·79 Posts Yup, this is the record now. A matrix of size 24M is about 36% the size of a matrix for SNFS1024. Would it be possible to run dependency #1 through the latest SVN version of msieve? It would be nice to see if the GMP square root code can scale to a number this large.
2009-08-17, 16:49   #7
bdodson

Jun 2005
lehigh.edu

210 Posts

Quote:
 Originally Posted by Andi_HB Wow ! Over 400 Million unique relations are impressive. Congratulation to this big job.
Sam's just updated his "Champions" page
Code:
Special number field sieve by SNFS difficulty:
5501	c307	2,1039-	K.Aoki+J.Franke+T.Kleinjung+A.K.Lenstra+D.A.Osvik
5739	c228	12,256+	T.Womack+B.Dodson
But if I recall correctly, this is the third factorization with over
400 Million unique relations collected, the other two being
5,389+ C265 and 2,908+ C268 (there was also 5, 383+ C267,
but that was easier, by snfs difficulty), all Childers/Dodson.
There's a fourth one pending, which Greg is currently working on
5,398+ C274, the first number done with Greg's binary of Serge's
new 16e siever (the others are with 15e).

So far as I know, it's the 433 Million unique that's the largest
successful filtering. I'm not sure which of Greg's was the largest
(not counting relations found but not successfully through filtering).

-Bruce

 2009-08-17, 19:05 #8 Batalov     "Serge" Mar 2008 Phi(4,2^7658614+1)/2 19×232 Posts Congratulations! The last Generalized Fermat! Huge difficulty number. If only you could have sieved it again, now with 16e. ;-) P.S. Do let Prof.Keller now. http://www1.uni-hamburg.de/RRZ/W.Keller/GFN12.html
2009-08-17, 21:19   #9
frmky

Jul 2003
So Cal

2,593 Posts

Quote:
 Originally Posted by jasonp Yup, this is the record now. A matrix of size 24M is about 36% the size of a matrix for SNFS1024. Would it be possible to run dependency #1 through the latest SVN version of msieve? It would be nice to see if the GMP square root code can scale to a number this large.
It's a bit more than 5,398+, which has 426561140 unique relations. These resulted in a 21354298 x 21354546 matrix, which is coming along, albeit slowly. The LA is 19.1% done.

2,908+ had 559633687 unique relations, but msieve couldn't make a matrix. I ended up using 488188552 unique relations to make a 20719167 x 20719414 matrix. I still have the original relations, so I should try it with the new filtering code.

2009-08-18, 09:23   #10
fivemack
(loop (#_fork))

Feb 2006
Cambridge, England

193616 Posts

Quote:
 Originally Posted by jasonp Yup, this is the record now. A matrix of size 24M is about 36% the size of a matrix for SNFS1024. Would it be possible to run dependency #1 through the latest SVN version of msieve? It would be nice to see if the GMP square root code can scale to a number this large.
Code:
Mon Aug 17 20:34:10 2009  Msieve v. 1.43
Mon Aug 17 20:34:13 2009  commencing square root phase
Mon Aug 17 20:34:13 2009  reading relations for dependency 1
Mon Aug 17 20:34:24 2009  read 12262248 cycles
Mon Aug 17 20:34:53 2009  cycles contain 38132421 unique relations
Mon Aug 17 20:46:51 2009  read 38132421 relations
Mon Aug 17 20:52:09 2009  multiplying 30857386 relations
Mon Aug 17 23:58:44 2009  multiply complete, coefficients have about 841.60 million bits
Mon Aug 17 23:58:51 2009  initial square root is modulo 35517907
Tue Aug 18 05:51:37 2009  sqrtTime: 33444
Tue Aug 18 05:51:37 2009  prp96 factor: 452271654045095376354829024468620655107168044537189917947981878284544891082485331470888529210881
Tue Aug 18 05:51:37 2009  prp132 factor: 293351100534073339320273736685554040546989773558978742766077630132017865996601983557083266543920963624936810354879103450020778081793
Tue Aug 18 05:51:37 2009  elapsed time 09:17:27
so it works but is about a factor two slower than 1.42. Though I'd not trust these timings since I was running up to seven other jobs on the i7 at the time, so at times msieve will have had only half a core.

Last fiddled with by fivemack on 2009-08-18 at 10:50

2009-08-18, 10:47   #11
10metreh

Nov 2008

2×33×43 Posts

Quote:
 Originally Posted by fivemack Msieve v. 1.43
Why does the latest SVN call itself 1.43?

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