Skip to content
Snippets Groups Projects

Resolve "Dokumentation CPU-Cores per GPU verbessern"

Merged Sebastian Döbel requested to merge 575-dokumentation-cpu-cores-per-gpu-verbessern into preview
All threads resolved!
Files
2
@@ -146,16 +146,15 @@ This is useful to document the cluster used or avoid accidentally using the wron
The number of cores per node that are currently allowed to be allocated for GPU jobs is limited
depending on how many GPUs are being requested.
On Alpha Centauri you may only request up to 6 cores per requested GPU.
This is because we do not wish that GPUs become unusable due to all cores on a node being used by
a single job which does not, at the same time, request all GPUs.
E.g., if you specify `--gres=gpu:2`, your total number of cores per node (meaning:
`ntasks`*`cpus-per-task`) may not exceed 12 (on Alpha Centauri)
`ntasks`*`cpus-per-task`) may not exceed 12 on [`Alpha Centauri`](alpha_centauri.md).
Note that this also has implications for the use of the `--exclusive` parameter.
Since this sets the number of allocated cores to 48, you also **must** request all eight GPUs
by specifying `--gres=gpu:8`, otherwise your job will not start.
Since this sets the number of allocated cores to the maximum, you also **must** request all GPUs
otherwise your job will not start.
In the case of `--exclusive`, it won't be denied on submission,
because this is evaluated in a later scheduling step.
Jobs that directly request too many cores per GPU will be denied with the error message:
Loading