Discussion related to cado-nfs

[Sudarshan Muralidhar <smural@seas.upenn.edu>]

Thanks, that fixed it.

One more issue that I've been running into for a few days:

Sometimes the Linear Algebra step fails with a long error message (reproduced below). In most of these cases, simply restarting the job (with the same parameters, so that the old caches for polynomial selection and pairs are retained) seems to solve the issue. Any ideas what might be causing this?

Error message:

On Wed Dec 10 2014 at 5:21:11 AM paul zimmermann <Paul.Zimmermann@inria.fr> wrote:

       Dear Sudarshan,

> From: Sudarshan Muralidhar <smural@seas.upenn.edu>
> Date: Wed, 10 Dec 2014 10:13:05 +0000
>
> Hello,
>
> I'm using CADO-NFS to update Nadia Heninger's Factoring as a Service
> Project.
>
> When using CADO in distributed mode to factor numbers, I have no issue for
> numbers below ~100 digits. However, when I try larger digits (RSA-120, for
> example), I get failed workunits, eventually leading to an aborted job.
> My error message is listed below - does it lend any insight to something I
> may be doing wrong?
>
> Thanks,
> Sudarshan Muralidhar
>
> Error:Polynomial Selection (size optimized): Program run on node015 failed
> with exit code 134
> Error:Polynomial Selection (size optimized): Stderr output follows (stored
> in file /job10/c120.upload/c120_polyselect1_220000-224000.u2mm_t.stderr0):
> b'# Warning: this code is experimental, and not thread-safe.
> code BUG() : condition newsize == size failed in insert_hash at
> /home/cado-nfs/polyselect/auxiliary.c:3073 -- Abort
> Aborted (core dumped)
> Error:Polynomial Selection (size optimized): Exceeded maximum number of
> failed workunits, maxfailed=100

this is a known issue. The new polynomial selection code is not thread safe.
You should add tasks.polyselect.threads=1 on the cadofactor.py command line.

Best regards,
Paul Zimmermann