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Subject: Re: [OMPI devel] OpenMPI, PLPA and Linux cpuset/cgroup support
From: Bert Wesarg (bert.wesarg_at_[hidden])
Date: 2009-07-22 13:54:30

On Wed, Jul 22, 2009 at 19:24, Jeff Squyres<jsquyres_at_[hidden]> wrote:
> Bert -- is this functionality something we'd want to incorporate into PLPA?
What functionality? The complete libcpuset or just the 'get me the
cpuset mask of this task'? I don't think its good if we duplicate the
whole functionality of the libcpuset and taking libcpuset as a
dependency of PLPA sounds too heavy. Actually I really don't know yet.

That the cpuset should be considered into the decision process of
ORTE/OMPI is out of question. But I think its suffice if ORTE/OMPI
query the current affinity mask and takes only these processors into
account. Whoever set this to something smaller than the cpuset mask or
the online mask (in absence of cpusets) needs to live with that
a-priori taken decision or knows what he is doing (maybe a batch
system without cpuset support).