[slurm-users] Node specs for Epyc 7xx3 processors?

[Steffen Grunewald]

On Wed, 2021-12-22 at 16:02:00 +0000, Stuart MacLachlan wrote:
> Hi Steffan,
> 
> Not sure if the output from 'numactl --hardware' is more consistent and easier to parse with a script or similar?

Hi,

I'm getting confusing results.
For an older dual 7351, there are 8 NUMA nodes, 4 physical cores each.
 (This already works with Slurm "Sockes=8 CorePerSocket=4".)
For a dual 7713 running Ubuntu, kernel 5.11, I get 2 NUMA nodes, one
per processor (64 physical cores, times 2).
I've seen "lscpu" output for a 7313 which also shows 8 nodes, 4 cores,
2 threads each, kernel 4.19, Debian Buster.
Does Ubuntu (or the 5.11 kernel) handle NUMA nodes difefrently?

Thanks,
 Steffen

> Hello,
> 
> I'm wondering whether there is some rule-of-thumb to translate the core config listed in https://urldefense.proofpoint.com/v2/url?u=https-3A__en.wikipedia.org_wiki_Epyc&d=DwIDAw&c=euGZstcaTDllvimEN8b7jXrwqOf-v5A_CdpgnVfiiMM&r=WRHOCjWNhD-hk2AQTjbVUqX9gELcVS7wxFXQqbJ02hk&m=tinTJJMaVo42Y9_sd_6GFqebHHPSHkAU7HWSxq9pJJk&s=4qtrnAVSz-nrQqws1E9H4JixtZQpj0dg3dtPszJpW1g&e= to the node information Slurm expects in "Sockets=x CoresPerSocket=y"? ("ThreadsPerCore=2" is clear.)
> 
> We'll be getting Epyc 7313 and 7513 machines, and perhaps add a single 7713 one - "lscpu" outputs are wildly different, while the total number of cores is correct.
> 
> Will I have to wait until the machines have arrived, and do some experiments, or did someone already retrieve the right numbers, and is willing to share?
> 
> Thanks,
>  Steffen

-- 
Steffen Grunewald, Cluster Administrator
Max Planck Institute for Gravitational Physics (Albert Einstein Institute)
Am Mühlenberg 1 * D-14476 Potsdam-Golm * Germany
~~~
Fon: +49-331-567 7274
Mail: steffen.grunewald(at)aei.mpg.de
~~~