mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > Factoring

Reply
 
Thread Tools
Old 2009-08-16, 12:17   #1
fivemack
(loop (#_fork))
 
fivemack's Avatar
 
Feb 2006
Cambridge, England

13×491 Posts
Default 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
fivemack is offline   Reply With Quote
Old 2009-08-16, 13:56   #2
bdodson
 
bdodson's Avatar
 
Jun 2005
lehigh.edu

210 Posts
Default

Quote:
Originally Posted by fivemack View Post
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
Sorry to hear about the card; but glad to hear that
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
bdodson is offline   Reply With Quote
Old 2009-08-16, 19:39   #3
fivemack
(loop (#_fork))
 
fivemack's Avatar
 
Feb 2006
Cambridge, England

13×491 Posts
Default

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
fivemack is offline   Reply With Quote
Old 2009-08-17, 10:12   #4
fivemack
(loop (#_fork))
 
fivemack's Avatar
 
Feb 2006
Cambridge, England

11000111011112 Posts
Default 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
File Type: bz2 12+256.mlog.bz2 (99.9 KB, 297 views)

Last fiddled with by fivemack on 2009-08-17 at 10:13
fivemack is offline   Reply With Quote
Old 2009-08-17, 10:49   #5
Andi_HB
 
Andi_HB's Avatar
 
Mar 2007
Germany

23·3·11 Posts
Default

Wow ! Over 400 Million unique relations are impressive.
Congratulation to this big job.
Andi_HB is offline   Reply With Quote
Old 2009-08-17, 14:01   #6
jasonp
Tribal Bullet
 
jasonp's Avatar
 
Oct 2004

33·131 Posts
Default

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.
jasonp is offline   Reply With Quote
Old 2009-08-17, 16:49   #7
bdodson
 
bdodson's Avatar
 
Jun 2005
lehigh.edu

210 Posts
Default

Quote:
Originally Posted by Andi_HB View Post
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
bdodson is offline   Reply With Quote
Old 2009-08-17, 19:05   #8
Batalov
 
Batalov's Avatar
 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

223118 Posts
Default

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
Batalov is offline   Reply With Quote
Old 2009-08-17, 21:19   #9
frmky
 
frmky's Avatar
 
Jul 2003
So Cal

1000001010002 Posts
Default

Quote:
Originally Posted by jasonp View Post
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.
frmky is offline   Reply With Quote
Old 2009-08-18, 09:23   #10
fivemack
(loop (#_fork))
 
fivemack's Avatar
 
Feb 2006
Cambridge, England

13·491 Posts
Default

Quote:
Originally Posted by jasonp View Post
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
fivemack is offline   Reply With Quote
Old 2009-08-18, 10:47   #11
10metreh
 
10metreh's Avatar
 
Nov 2008

2·33·43 Posts
Default

Quote:
Originally Posted by fivemack View Post
Msieve v. 1.43
Why does the latest SVN call itself 1.43?
10metreh is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Connectivity Matrix Xyzzy Lounge 13 2017-02-21 18:29
GF(2) Matrix request oslik Factoring 22 2008-11-02 12:53
[Need help] about Matrix Polynomial buan Homework Help 3 2007-07-17 15:07
CWI Matrix Solver R.D. Silverman NFSNET Discussion 6 2006-03-19 17:56
The Matrix + Table Tennis = ? Xyzzy Lounge 8 2003-08-30 16:07

All times are UTC. The time now is 07:57.

Sat May 8 07:57:04 UTC 2021 up 30 days, 2:37, 0 users, load averages: 6.21, 5.34, 4.67

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.