[QUOTE=RichD;416713]Found a good poly.
[CODE]N: 1561248012875604421290997452712948651673429631296532916308406424711670868236536811765897539577054945788349762744593204554580205942062187848423188814351767445694628965970805839
# expecting poly E from 1.73e-13 to > 1.99e-13
R0: -2921485258420054233795687624707655
R1: 11197286481893873
A0: -3648904307721440541363054106517980023512992
A1: -1228544630159808525398670589488439616
A2: -2336973510196735534005200082
A3: 4718033960360448430271
A4: -613255320209996
A5: 7335900
# skew 18500902.09, size 5.225e-17, alpha -9.145, combined = 1.915e-13 rroots = 3[/CODE][/QUOTE]

Are you running Linux or windows?

Linux with GTX 560 Ti.

Anybody here have a willing to give a try to use CADO polynomial selection, I receive a message from Maksym who seems think CADO is better than msieve when doing the polynomial selection stage.
Currently, I , Wenjie, Kurt, and Maksym is factoring 10^2340-1 using gnfs method, the poly is searched by Kurt and Maksym. Kurt uses msieve with a gpu card sieve a month, Maksym uses CADO sieve two weeks. Maksym 's poly line sieve 30% faster than Kurt's.

Here is Maksym's feeling through the sieve.
[CODE]"Hi guys,
Sorry for the late reply.
Read my old letter below. If you still have questions, please ask.
I believe I used this image for Ubuntu 12.04:
http://sourceforge.net/projects/osboxes/files/vms/vbox/Ubuntu/12.04/Ubuntu_12.04-64bit.7z/download
Username: osboxes
Password: osboxes.org
My (somewhat checked) observations about CADO:
1) You can download a development version after 2.1.1 from a git repository, they have a link on the site now.
2) Relation sieving in CADO inside VirtualBox is slower than relation sieving in msieve in Windows on the same machine.
3) VirtualBox allows using only a fraction of machine memory, e.g. if you have 8 Gb in Windows, you'll have ~5 Gb in Ubuntu.
4) A good msieve polynomial cannot be optimized by CADO. It does the job but the root optimized polynomial is always worse.
5) For the same reason, you can't make a SNFS polynomial better by running it through CADO root optimization.
6) CADO can't use GPU.
BUT:
1) Polynomial selection in CADO is extremely good. I bet I can find a better polynomial in CADO than in GPU msieve, in less time, and probably consuming less electricity too.
Let me know,
Max
Hi all,
This is how I installed CADO on my Windows 7 machine:
https://bitbucket.org/cybertools/malware_tools/issues/22/virtualbox-ubuntu-installation. Just download the latest CADO 2.1.1 instead of referred CADO 2.0 and ignore the bitbucket script altogether. Also make sure to switch BIOS to operate 64 bit Ubuntu in VirtualBox if you have a 64 bit machine.
Max "[/CODE]

Is he willing to share the two polys being compared for 10^2340-1?

Also what sort of GPU was Kurt using? And how was he using it (used the wrong way you could easily waste a lot of search time)?

Chris

[QUOTE=wreck;416866]...Maksym who seems think CADO is better than msieve when doing the polynomial selection stage.
Currently, I , Wenjie, Kurt, and Maksym is factoring 10^2340-1 using gnfs method, the poly is searched by Kurt and Maksym. Kurt uses msieve with a gpu card sieve a month, Maksym uses CADO sieve two weeks. Maksym 's poly line sieve 30% faster than Kurt's.
[/QUOTE]
That's the 2340L (i.e. the 10,1170+ L, with M already factored) [URL="http://stdkmd.com/nrr/repunit/phin10.cgi?p=24#N2340L"]c189[/URL] cofactor, right? (10^2340-1 also has the 10,585- c266 cofactor.)

CADO does have a good poly selector. Good idea for someone to try it!..

[QUOTE=Dubslow;416867]Is he willing to share the two polys being compared for 10^2340-1?[/QUOTE]

Kurt's poly (found by msieve)
[CODE]
n: 952292197412453381717073518174919932906570614453890307718545364847038044348090273591549618739487450764456259682247432651918464778452105306957838135819115896078660572289957993060613591472021
# norm 1.484895e-018 alpha -8.148489 e 1.926e-014 rroots 5
skew: 1072448109.23
c0: 2768823872072333261931988968816202213195947984000
c1: 15275653385062057929219319069678526857760
c2: -138387764172029764068756785487648
c3: -117360940966783947764667
c4: 122686529654486
c5: 9240
Y0: -10060501899165771381498290805092655859
Y1: 31126454643178352737
type: gnfs
rlim: 200000000
alim: 200000000
lpbr: 32
lpba: 32
mfbr: 64
mfba: 94
rlambda: 2.6
alambda: 3.6
[/CODE]

Max's poly (found by CADO)
[CODE]
n: 952292197412453381717073518174919932906570614453890307718545364847038044348090273591549618739487450764456259682247432651918464778452105306957838135819115896078660572289957993060613591472021
# MurphyE = 1.09e-11
# lognorm 58.91
skew: 45137920.0
c0: -197006411290915294206892058826736550862182325
c1: -96891972101929844956190270575674132078
c2: 1564572888018669862818629860418
c3: 73230310522607368819384
c4: -190657861142439
c5: 1640100
Y0: -3570923609932057924385087593377792638
Y1: 205226838884523100253827
type: gnfs
rlim: 200000000
alim: 200000000
lpbr: 32
lpba: 32
mfbr: 64
mfba: 94
rlambda: 2.6
alambda: 3.6
[/CODE]

We sieve special q from 23M to 110M.
On an i3 processor, and q=60M, range to 60M+100, the 1st poly's sieve speed is 0.896 sec/rel,
the 2nd poly's sieve speed is 0.637 sec/rel.
other ranges got similar result.

[QUOTE=chris2be8;416875]Also what sort of GPU was Kurt using? And how was he using it (used the wrong way you could easily waste a lot of search time)?

Chris[/QUOTE]
I'm not sure which GPU card Kurt is using, the steps is taken under the introductions from msieve's readme file,
It is the first time Kurt to use msieve's GPU version to search polynomial.
Before this , I and him use his i7 CPU search about 4 c15x to c16x numbers' polynomial,
most time, we use -np1 to find some candidates, and select the biggest e score polynomial as the final poly files.
For this number , the -np2 seems used too.
On the other hand, it is the first time of Max using CADO to search the polynomial too.
It seems like the skew of CADO and msieve is not the same, and the second poly's skew is get from CADO.
Max also give a try to the number 10^429-1, he says the skew should the value from
[url]http://myfactors.mooo.com/[/url]
after given the polynomials.

Anyway, this is not the point I want to express, maybe the polynomial we choose from msieve is not good enough,
and maybe both the way Kurt and Max is not the right way,
I want to point out that there is another tool exist public there , its name is CADO, that could used to do the polynomial
sieve. It would be nice to see more people to use it, to see whether it is better than msieve.

Max sent me an article ,
SHI BAI, CYRIL BOUVIER , ALEXANDER KRUPPA, and PAUL ZIMMERMANN,
"BETTER POLYNOMIAL FOR GNFS", 2010, MATHEMATICS OF COMPUTATION
In this paper, they exclaim they find some better polynomials for RSA768 and two polynomials for RSA1024 ,
using the algorithm implemented in CADO-NFS.
.

[QUOTE=Batalov;416900]That's the 2340L (i.e. the 10,1170+ L, with M already factored) [URL="http://stdkmd.com/nrr/repunit/phin10.cgi?p=24#N2340L"]c189[/URL] cofactor, right? (10^2340-1 also has the 10,585- c266 cofactor.)

CADO does have a good poly selector. Good idea for someone to try it!..[/QUOTE]
Yes, it is the number 10, 1170L, if use the tag system similar to Cunningham number.
Kurt abbreviates this number as R2340L, it is a 189 digits number.

By the way , it seems that the number 6,448+ keep silence quite a time , Bruce told me
"Sieving was finished long ago, with Batalov's polynomial selection.
I haven't gotten a chance to run the matrix."
I am not sure wheter it is becuase the memory issue which would meet
on most big number.
Do you have machine with 32GB?
Is it possible you run the postprocessing of this number?

Nope, my postprocessing B+D years are behind me. (Especially for this size.)
Bruce was in contact with Greg about running MPI on his cluster for this number; that's the last I heard about that project and that was quite a while ago.

C175 @ i5241
 

[QUOTE=RichD;416713]Found a good poly.
[/QUOTE]

Here is one, that sieves about 5-10% better:

[CODE]
n: 1561248012875604421290997452712948651673429631296532916308406424711670868236536811765897539577054945788349762744593204554580205942062187848423188814351767445694628965970805839
# norm 7.864265e-17 alpha -7.895789 e 2.263282e-13 rroots 3
skew: 41354998.50
c0: 2217406006295087501003654530136566330136640
c1: 74149137268999111127815029367344384
c2: -30723141702894761175690717314
c3: -360911433696642764671
c4: 4122762472806
c5: 110880
Y0: -6756530390688759011127125642945779
Y1: 3599383523628534041
[/CODE]