[slurm-users] exclusive or not exclusive, that is the question

[Marcus Wagner]

Just made another test.


Thanks god, the exclusivity is not "destroyed" completely, only on job 
can run on the node, when the job is exclusive. Nonetheless, this is 
somewhat unintuitive.
I wonder, if that also has an influence on the cgroups and the process 
affinity/binding.

I will do some more tests.


Best
Marcus

On 8/20/19 9:47 AM, Marcus Wagner wrote:
> Hi Folks,
>
>
> I think, I've stumbled over a BUG in Slurm regarding the 
> exclusiveness. Might also, I've misinterpreted something. I would be 
> happy, if someone could explain that to me in the latter case.
>
> To the background. I have set PriorityFlags=MAX_TRES
> The TRESBillingWeights are "CPU=1.0,Mem=0.1875G" for a partition with 
> 48 core nodes and RealMemory 187200.
>
> ---
>
> I have two jobs:
>
> job 1:
> #SBATCH --exclusive
> #SBATCH --ntasks=2
> #SBATCH --nodes=1
>
> scontrol show <jobid> =>
>    NumNodes=1 NumCPUs=48 NumTasks=2 CPUs/Task=1 ReqB:S:C:T=0:0:*:*
>    TRES=cpu=48,mem=187200M,node=1,billing=48
>
> exactly, what I expected, I got 48 CPUs and therefore the billing is 48.
>
> ---
>
> job 2 (just added mem-per-cpu):
> #SBATCH --exclusive
> #SBATCH --ntasks=2
> #SBATCH --nodes=1
> #SBATCH --mem-per-cpu=5000
>
> scontrol show <jobid> =>
>    NumNodes=1-1 NumCPUs=2 NumTasks=2 CPUs/Task=1 ReqB:S:C:T=0:0:*:*
>    TRES=cpu=2,mem=10000M,node=1,billing=2
>
> Why "destroys" '--mem-per-cpu' exclusivity?
>
>
>
> Best
> Marcus
>

-- 
Marcus Wagner, Dipl.-Inf.

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