[torqueusers] MPI jobs not tied to nodes/ppn configuration
siegert at sfu.ca
Fri Oct 16 09:40:04 MDT 2009
only works on SMPs. What you are looking for is
but you need a scheduler that supports the procs resource
(recent versions of moab do, don't know about maui).
Head, Research Computing
WestGrid Site Lead
IT Services phone: 778 782-4691
Simon Fraser University fax: 778 782-4242
Burnaby, British Columbia email: siegert at sfu.ca
Canada V5A 1S6
On Thu, Oct 15, 2009 at 02:39:33PM -0600, Jerry Smith wrote:
> This is dependent on how the scheduler is setup ( if you allow multiple
> jobs on a single node etc ).
> But I believe you can use:
> qsub -l ncpus=X ... where X is the total number of cpus you need.
> rozelak at volny.cz wrote:
> > Hallo,
> > I have access to heterogeneous clusters with many multi-core/processor
> > nodes, where PBSPro is installed. When I want to start MPI job, I need
> > to specify how many nodes, and how many CPUs per node I want. E.g.,
> > when I require 32 MPI processes, I need to run it as:
> > qsub -l nodes=16:ppn=2 ...
> > The problem is, that PBS will wait until there are at lest 16 nodes,
> > each with 2 cores free, even if there are more that 32 cores free (e.g.
> > 15 nodes with 2 free cores each + 2 and more nodes with one free core,
> > giving 32+ free cores available). This can be found for any nodes/ppn
> > combination, e.g.:
> > qsub -l nodes=32:ppn=1 ...
> > will not be started on 31 nodes with 4+ free cores (having 124 cores
> > free!). What I need is just to say -- I need XY cores/processors for
> > my job in a cluster, and I do not care how many nodes it will be started
> > on, while each node may allocate different number of cores.
> > So, the question is: is 'torque' able to handle such cases? And how?
> > If so, I will talk about it with our clusters admins, as I remember
> > that they considered the migration from PBS and they are opened to our(users)
> > wishes.
> > Thank you very much for your answer,
> > Dan T.
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