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

[Brian Andrus]

I would be surprised if it were compiled without the support. However, 
you could check and run something like:

strings /sbin/slurmctld | grep job_submit

(or where ever your slurmctld binary is). There should be quite a few 
lines with that in it.

Brian Andrus

On 9/1/2022 10:54 AM, Davide DelVento wrote:
> Thanks Brian for the suggestion, which I am now exploring.
>
> The documentation is a bit cryptic for me, but exploring a few things
> and checking https://funinit.wordpress.com/2018/06/07/how-to-use-job_submit_lua-with-slurm/
> I suspect my slurm install (provided by cluster vendor) was not
> compiled with the lua plugin installed. Do you know how to verify if
> that is the case or if it's something else? I don't see a way to show
> if the plugin is actually being "seen" by slurm, and I suspect it's
> not.
>
> Does anyone else have other suggestions or comment on either the
> plugin or the prolog workaround?
>
> Thanks!
>
>
> On Tue, Aug 30, 2022 at 3:01 PM Brian Andrus <toomuchit at gmail.com> wrote:
>> 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!
>>>