Discussion related to cado-nfs

[Emmanuel Thomé <Emmanuel.Thome@inria.fr>]

Ross,

Paul has provided guidance on your second question which is how you you
should go in order to start the computation on another machine based on
the polynomials and relations that you already had from the first run.

As regards your initial problem: I don't see in your c175.log that the
computation stops within linear algebra (sorry if I've missed it).

What I do see is that:

 - in some runs, the computation stops abruptly after the duplicates
   removal pass (first pass of the filtering step).

 - I see that there's a run dated 2021-11-16 which went as far as the
   replay step (last step of the filtering), but crashed there. The file 

   c175.replay.stdout.4
   c175.replay.stderr.4

   would possibly provide further insight.

Note however that in both cases, my educated guess is that you ran out of
memory. Your machine's dmesg output might confirm this.

E.

On Mon, Jan 31, 2022 at 11:26:43AM +0100, Paul Zimmermann wrote:
>        Dear Ross,
> 
> > I am not sure if this is the right place to email, but I am interested in
> > finding the factorisation of a particular 177-digit number that I have
> > found. I think I have successfully performed the "Polynomial Selection" 
> > and
> > "Lattice Sieving" Steps, but for some reason the program halts (with no
> > clear reason in the logs) within 3-5 minutes of starting the "Linear
> > Algebra" step. 
> 
> yes it is the right place. There might be plenty of reasons. Sending the 
> logs
> might help.
> 
> > I am thinking about trying on a different machine, but I am not 100% sure
> > how to do this (e.g. which files would I need to copy over from the 
> > working
> > directory of the server? Presumably I would need to change some of the
> > config files too?). I am not sure how best to proceed from here. 
> 
> see scripts/cadofactor/README.md on how to import a polynomial and 
> relations.
> 
> Best regards,
> Paul Zimmermann