mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > Msieve

Reply
 
Thread Tools
Old 2016-12-07, 17:53   #1
pinhodecarlos
 
pinhodecarlos's Avatar
 
"Carlos Pinho"
Oct 2011
Milton Keynes, UK

3·1,621 Posts
Default lanczos error: submatrix is not invertible

Just don't understand this error. LA was restarted after 3 days with a "lanczos error: submatrix is not invertible" whilst away from the machine. What's this about? Should I cancel this job and sieve more?


Code:
Sat Dec  3 23:38:13 2016  commencing Lanczos iteration (8 threads)
Sat Dec  3 23:38:13 2016  memory use: 5457.8 MB
Sat Dec  3 23:39:30 2016  linear algebra at 0.0%, ETA 190h16m
Sat Dec  3 23:39:54 2016  checkpointing every 80000 dimensions
Wed Dec  7 16:54:36 2016  lanczos error: submatrix is not invertible
Wed Dec  7 16:54:36 2016  lanczos halted after 109172 iterations (dim = 6903580)
Wed Dec  7 16:54:36 2016  linear algebra failed; retrying...
Wed Dec  7 16:54:36 2016  commencing Lanczos iteration (8 threads)
Wed Dec  7 16:54:36 2016  memory use: 5457.8 MB
Wed Dec  7 16:55:52 2016  linear algebra at 0.0%, ETA 187h32m
Wed Dec  7 16:56:15 2016  checkpointing every 80000 dimensions

Edit: Didn't think about this error algebra related. I understand its concept. What should I do next, sieve more?
Attached Thumbnails
Click image for larger version

Name:	Untitled.jpg
Views:	86
Size:	211.9 KB
ID:	15276  

Last fiddled with by pinhodecarlos on 2016-12-07 at 18:21
pinhodecarlos is offline   Reply With Quote
Old 2016-12-07, 18:50   #2
Batalov
 
Batalov's Avatar
 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2

100100011011002 Posts
Default

This error is memory related. Every time we saw it, it was due to memory ever so slightly faulty.

One thing to try is to rename *.bak.chk (if you were able to save it) to .chk and try to restart.
Batalov is offline   Reply With Quote
Old 2016-12-07, 19:05   #3
pinhodecarlos
 
pinhodecarlos's Avatar
 
"Carlos Pinho"
Oct 2011
Milton Keynes, UK

3×1,621 Posts
Default

Quote:
Originally Posted by Batalov View Post
This error is memory related. Every time we saw it, it was due to memory ever so slightly faulty.

One thing to try is to rename *.bak.chk (if you were able to save it) to .chk and try to restart.
Thank you. I've restarted it with the 3 pm GMT backup file. Let´s see what happens.

Last fiddled with by pinhodecarlos on 2016-12-07 at 19:32
pinhodecarlos is offline   Reply With Quote
Old 2016-12-10, 10:40   #4
fivemack
(loop (#_fork))
 
fivemack's Avatar
 
Feb 2006
Cambridge, England

2·3,191 Posts
Default

Quote:
Originally Posted by Batalov View Post
This error is memory related. Every time we saw it, it was due to memory ever so slightly faulty.
Bother, I got a great swathe of this error on my three-year-old i7-4930K machine over the last couple of days.

I have noticed that I see it more when running cudalucas, giving me a slight question as to whether it's a driver problem rather than a physical defect.

(that is, I was getting it once every five minutes, and after a reboot I've got it zero times in twelve hours)

Last fiddled with by fivemack on 2016-12-10 at 22:58
fivemack is online now   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
"lanczos error: only trivial dependencies found" with massive oversieving eigma Msieve 21 2015-05-28 03:27
lanczos error: submatrix is not invertible Mini-Geek Msieve 6 2014-02-13 14:38
Initial vector in Lanczos Robert Holmes Miscellaneous Math 4 2010-09-11 01:34
Lanczos error Andi47 Msieve 7 2009-01-11 19:33
Msieve Lanczos scalability Jeff Gilchrist Msieve 1 2009-01-02 09:32

All times are UTC. The time now is 18:03.

Wed Feb 24 18:03:04 UTC 2021 up 83 days, 14:14, 0 users, load averages: 2.24, 2.07, 1.86

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.