[slurm-users] Notify users about job submit plugin actions

[Jeffrey T Frey]

In case you're developing the plugin in C and not LUA, behind the scenes the LUA mechanism is concatenating all log_user() strings into a single variable (user_msg).  When the LUA code completes, the C code sets the *err_msg argument to the job_submit()/job_modify() function to that string, then NULLs-out user-msg.  (There's a mutex around all of that code so slurmctld never executes LUA job submit/modify scripts concurrently.)  The slurmctld then communicates that returned string back to sbatch/salloc/srun for display to the user.


Your C plugin would do likewise — set *err_msg before returning from job_submit()/job_modify() — and needn't be mutex'ed if the code is reentrant.






> On Jul 19, 2023, at 08:37, Angel de Vicente <angel.de.vicente at iac.es> wrote:
> 
> Hello Lorenzo,
> 
> Lorenzo Bosio <lorenzo.bosio at unito.it> writes:
> 
>> I'm developing a job submit plugin to check if some conditions are met before a job runs.
>> I'd need a way to notify the user about the plugin actions (i.e. why its jobs was killed and what to do), but after a lot of research I could only write to logs and not the user shell.
>> The user gets the output of slurm_kill_job but I can't find a way to add a custom note.
>> 
>> Can anyone point me to the right api/function in the code?
> 
> In our "job_submit.lua" script we have the following for that purpose:
> 
> ,----
> |           slurm.log_user("%s: WARNING: [...]", log_prefix)
> `----
> 
> -- 
> Ángel de Vicente
> Research Software Engineer (Supercomputing and BigData)
> Tel.: +34 922-605-747
> Web.: http://research.iac.es/proyecto/polmag/
> 
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