Yeah, I've found that in those situations to have people wrap their threaded programs in srun inside of sbatch.  That way the scheduler knows which process specifically gets the threading.

-Paul Edmon-

On 02/22/2018 10:39 AM, Loris Bennett wrote:
Hi Paul,

Paul Edmon <> writes:

At least from my experience wonky things can happen with slurm
(especially if you have thread affinity on) if you don't rightly
divide between -n and -c.  In general I've been telling our users that
-c is for threaded applications and -n is for rank based parallelism.
This way the thread affinity works out properly.
Actually we have do an issue with some applications not respecting the
CPU mask.  I always assumed it was something to do with the way the
multithreading was programmed in certain applications, but maybe we
should indeed be getting the users to use multiple CPUs with a single

Thanks for the info.



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