[slurm-users] License management and invoking scontrol in the prolog

[Brian Andrus]

Not sure if you can do all the things you intend, but the job_submit 
script is precisely where you want to check submission options.

https://slurm.schedmd.com/job_submit_plugins.html

Brian Andrus

On 8/30/2022 12:58 PM, Davide DelVento wrote:
> Hi,
>
> I would like to soft-enforce license utilization only when the -L is
> set. My idea: check in the prolog if the license was requested and
> only if it were, set the environmental variables needed for the
> license.
>
> I looked at all environmental variables set by slurm and did not find
> any related to the license as I was hoping.
>
> As a workaround, I could check
>
> scontrol show job $SLURM_JOB_ID | grep License
>
> and that would work, but (as discussed in other messages in this list)
> the documentation at https://slurm.schedmd.com/prolog_epilog.html say
>
>> Prolog and Epilog scripts should be designed to be as short as possible
>> and should not call Slurm commands (e.g. squeue, scontrol, sacctmgr,
>> etc). [...] Slurm commands in these scripts can potentially lead to performance
>> issues and should not be used.
> This is a bit of a concern, since the prolog would be invoked for
> every job on the cluster, and it's a prolog (rather than the epilogue
> like discussed in earlier messages).
>
> So two questions:
>
> 1) is there a better workaround to check in the prolog if the current
> job requested a license and/or
> 2) would this kind of use of scontrol be okay or is indeed a concern
>
> Thanks!
>