[slurm-users] [External] slurmd -C vs lscpu - which do I use to populate slurm.conf?

[Ole Holm Nielsen]

On 4/29/21 1:06 AM, Michael Robbert wrote:
> I think that you want to use the output of slurmd -C, but if that isn’t 
> telling you the truth then you may not have built slurm with the correct 
> libraries. I believe that you need to build with hwloc in order to get the 
> most accurate details of the CPU topology. Make sure you have hwloc-devel 
> installed and try to rebuild Slurm.

Slurm has many prerequisites for building, see what I believe is the full 
list here: 
https://wiki.fysik.dtu.dk/niflheim/Slurm_installation#install-prerequisites

If you have recent Xeon or EPYC CPUs, you should also consider the number 
of NUMA domains per socket.  Use numactl -H to see what you've got.

Regarding slurmd -C and multiple NUMA domain per socket, there's a small 
bug being sorted out in https://bugs.schedmd.com/show_bug.cgi?id=11434

It may be beneficial for HPC applications to enable Sub NUMA Cluster (SNC) 
in BIOS, see 
https://www.dell.com/support/kbdoc/da-dk/000176921/bios-characterization-for-hpc-with-intel-cascade-lake-processors

/Ole