[slurm-users] Job runtime

[Mahmood Naderan]

Thanks for the exaplnation Chris. I will read cgroup.

Regards,
Mahmood




On Sun, Mar 18, 2018 at 7:43 AM, Chris Samuel <chris at csamuel.org> wrote:
> On Sunday, 18 March 2018 5:46:50 AM AEDT Mahmood Naderan wrote:
>
>> Excuse me but I think that is wrong.
>
> I think we're talking at cross-purposes, I thought you were puzzled about why
> CPU time was less than the total time in a general context (not purely within
> Slurm).
>
>> "Elapsed" is the wall clock time.
>
> Correct.
>
>> "UserCPU" should be "NCPUS*Elapsed".
>
> No, that's CPUTime (as mentioned in the sacct manual page).
>
> UserCPU is a measure of the time that the CPU spent running the program in
> user space as reported by the kernel.  Note the caveat about it on the sacct
> manual page:
>
> https://slurm.schedmd.com/sacct.html
>
> Also note that how you tell Slurm to gather statistics affects its accuracy.
> I've pretty much always used the cgroup method as that seems to give better
> accuracy to me (especially for memory usage).
>
> All the best,
> Chris
> --
>  Chris Samuel  :  http://www.csamuel.org/  :  Melbourne, VIC
>
>