[slurm-users] NumNodes=1 NumCPUs=2 NumTasks=1 CPUs/Task=1 ???

[Antony Cleave]

if you want slurm to just ignore the difference between physical and
logical cores then you can change
SelectTypeParameters=CR_Core
to
SelectTypeParameters=CR_CPU

and then it will treat threads as CPUs and then it will let you start the
number of tasks you expect

Antony

On Thu, 7 Feb 2019 at 18:04, Jeffrey Frey <frey at udel.edu> wrote:

> Your nodes are hyperthreaded (ThreadsPerCore=2).  Slurm always allocates
> _all threads_ associated with a selected core to jobs.  So you're being
> assigned both threads on core N.
>
>
> On our development-partition nodes we configure the threads as cores, e.g.
>
>
> NodeName=moria CPUs=16 Boards=1 SocketsPerBoard=2 CoresPerSocket=8
> ThreadsPerCore=1
>
>
>
> to force Slurm to schedule the threads separately.
>
>
>
> On Feb 7, 2019, at 12:10 PM, Xiang Gao <qasdfgtyuiop at gmail.com> wrote:
>
> Hi All,
>
> We configured slurm on a server with 8 GPU and 16 CPUs and want to use
> slurm to scheduler for both CPU and GPU jobs. We observed an unexpected
> behavior that, although there are 16 CPUs, slurm only schedule 8 jobs to
> run even if there are jobs not asking any GPU. If I inspect detailed
> information using `scontrol show job`, I see some strange thing on some job
> that just ask for 1 CPU:
>
> NumNodes=1 NumCPUs=2 NumTasks=1 CPUs/Task=1
>
> If I understand these concepts correctly, as the number of nodes is 1,
> number of tasks is 1, and number of cpus/task is 1, in principle there is
> no way that the final number of CPUs is 2. I'm not sure if I misunderstand
> the concepts, configure slurm wrongly, or this is a bug. So I come for help.
>
> Some related config are:
>
> # COMPUTE NODES
> NodeName=moria CPUs=16 Boards=1 SocketsPerBoard=2 CoresPerSocket=4
> ThreadsPerCore=2 RealMemory=120000
> Gres=gpu:gtx1080ti:2,gpu:titanv:3,gpu:v100:1,gpu:gp100:2
> State=UNKNOWN
> PartitionName=queue Nodes=moria Default=YES MaxTime=INFINITE State=UP
>
> # SCHEDULING
> FastSchedule=1
> SchedulerType=sched/backfill
> GresTypes=gpu
> SelectType=select/cons_res
> SelectTypeParameters=CR_Core
>
> Best,
> Xiang Gao
>
>
>
> ::::::::::::::::::::::::::::::::::::::::::::::::::::::
> Jeffrey T. Frey, Ph.D.
> Systems Programmer V / HPC Management
> Network & Systems Services / College of Engineering
> University of Delaware, Newark DE  19716
> Office: (302) 831-6034  Mobile: (302) 419-4976
> ::::::::::::::::::::::::::::::::::::::::::::::::::::::
>
>
>
>
>
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