Discussion related to cado-nfs

[Zimmermann Paul <Paul.Zimmermann@inria.fr>]

       Andrew,

> Date: Sat, 24 May 2014 21:35:20 -0400
> From: Andrew Johnston <ajohnston9@fordham.edu>
> 
> Hello all,
> 
> Before I begin, I'd like to thank everyone in advance for helping a
> beginner out.
> 
> For starters, I plan on running CADO on a cluster. I believe the cluster
> has a job submitter that manages the number of cores a program uses. Are
> there any ways to ensure CADO uses all of the allotted cores? Right now I'm
> running it on a computer with no restrictions and its only using ~1% of the
> CPU. I only have access to this cluster for a certain amount of time and I
> want to be sure I'm maximizing my usage.

there are several parts of CADO-NFS that can use several cores:
1) polynomial selection
2) sieving
3) linear algebra
For 1) and 2) it is much easier with CADO-NFS 2.0 and the upcoming version 
2.1.
The corresponding documentation is in scripts/cadofactor/README. Does it 
answer
your question?

> Secondly, I was wondering if you had any resources on how GNFS determines
> free relations and whether a relation is 'useful'. If you had any
> documentation on how that is done that you could refer me to I'd be very
> appreciative. I tried going through the source code but I couldn't quiet
> understand the logic

we don't have documentation on how free relations are computed in CADO-NFS,
but you should find that in any text book about NFS. For 'useful' relations,
what do you mean?

Best regards,
Paul Zimmermann