[slurm-users] unable to run on all the logical cores

[Diego Zuccato]

Il 08/10/20 08:19, David Bellot ha scritto:

> good spot. At least, scontrol show job is now saying that each job only
> requires one "CPU", so it seems all the cores are treated the same way now.
> Though I still have the problem of not using more than half the cores.
> So I suppose it might be due to the way I submit (batchtools in this
> case) the jobs.
Maybe R is generating single-threaded code? In that case, only a single
process can run on a given core at a time (processes does not share
memory map, threads do, and on Intel CPUs there's a single MMU per core,
not one per thread as in some AMDs).

-- 
Diego Zuccato
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