mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > Msieve

Reply
 
Thread Tools
Old 2019-08-26, 07:32   #1
fivemack
(loop (#_fork))
 
fivemack's Avatar
 
Feb 2006
Cambridge, England

6,323 Posts
Default Polynomial selection very strange in SVN 1030M

I'm trying to run some polynomial selection on a C194 with an updated msieve, and it is choosing a much sparser set of initial coefficients (some ranges of 10000 c5 have no valid initial coefficient) and then wanting to run each coefficient for a hundred days! Maybe 1600 seconds was a bit short, but 8640000 seconds is implausibly long.
fivemack is offline   Reply With Quote
Old 2019-08-27, 05:19   #2
Gimarel
 
Apr 2010

100100002 Posts
Default

I guess this is because of a patch to yafu/msieve that I posted. I use this to factor smaller composites and did not care for composites above C160.

I've set the timeout so big to disable it because in my experience it's better to set the stage1_norm to a value that stage1 can finish in time.

The high_coeff_multiplier is set to 360 because in my experience the overall chance to find a good poly is better with a smoother leading coefficiant. But most likely this is not the optimal value.
Gimarel is offline   Reply With Quote
Old 2019-08-27, 08:37   #3
xilman
Bamboozled!
 
xilman's Avatar
 
"π’‰Ίπ’ŒŒπ’‡·π’†·π’€­"
May 2003
Down not across

3·43·79 Posts
Default

Quote:
Originally Posted by Gimarel View Post
I guess this is because of a patch to yafu/msieve that I posted. I use this to factor smaller composites and did not care for composites above C160.
Wah!

Some of us very much care.
xilman is offline   Reply With Quote
Old 2019-08-27, 10:11   #4
Gimarel
 
Apr 2010

24×32 Posts
Default

Quote:
Originally Posted by xilman View Post
Wah!

Some of us very much care.
I do polyselect for larger numbers but I don't have generic parameters.

The patch was never intended to be incorporated into msieve, at least not for parameters above C160.
Gimarel is offline   Reply With Quote
Old 2019-08-27, 15:18   #5
jasonp
Tribal Bullet
 
jasonp's Avatar
 
Oct 2004

3·1,163 Posts
Default

The configuration for large polyselect jobs does many fairly outlandish things; I guess it's worth revisiting how configuration works so that we can get sensible defaults even without user-specific configuration.
jasonp is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Polynomial selection Max0526 NFS@Home 9 2017-05-20 08:57
Improved NFS polynomial selection jasonp Operation Kibibit 5 2014-09-07 11:02
2^877-1 polynomial selection fivemack Factoring 47 2009-06-16 00:24
Polynomial selection CRGreathouse Factoring 2 2009-05-25 07:55
Strange behavior of polynomial selection ET_ Msieve 5 2008-12-24 14:45

All times are UTC. The time now is 18:42.

Tue Nov 24 18:42:14 UTC 2020 up 75 days, 15:53, 4 users, load averages: 2.31, 1.80, 1.65

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, 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.