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Subject: Re: [OMPI users] OpenMPI with SGE: "-np N" for mpirun needed?
From: Ricardo Reis (rreis_at_[hidden])
Date: 2012-05-09 16:22:18


On Wed, 9 May 2012, Jiri Polach wrote:

> Dear all,
>
> is "-np N" parameter needed for mpirun when running jobs under SGE
> environment? All examples in
>
> http://www.open-mpi.org/faq/?category=running#run-n1ge-or-sge
>
> show that "-np N" is used, but in my opinion it should be redundant: mpirun
> should determine all parameters from SGE environment anyway. If there is "no
> need to specify what nodes to run on" (as stated in FAQ), it should not be
> necessary to specify the number of processors either.
>
> I ran some tests and it seems that mpirun correctly gets number of processors
> from SGE, but I would like to have some more solid confirmation.

You might want to use a smaller number of processors than those made
available by SGE.

  best,

  Ricardo Reis

  'Non Serviam'

  PhD/MSc Mechanical Engineering | Lic. Aerospace Engineering

  Computational Fluid Dynamics, High Performance Computing, Turbulence
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