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Subject: Re: [OMPI devel] Revise paffinity method?
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2009-05-08 10:37:52


On May 8, 2009, at 10:32 AM, Ralph Castain wrote:

> Actually, I was wondering (hot tub thought for the night) if the
> paffinity system can't just tell us if the proc has been bound or not?
> That would remove the need for YAP (i.e., yet another param).
>

Yes, it can.

What it can't tell, though, is who set it. So a user may have
overridden the paffinity after main() starts but before MPI_INIT is
invoked.

But perhaps that's not a crime -- users can override the paffinity at
their own risk (we actually have no way to preventing them from doing
so). So perhaps just checking if affinity is already set is a "good
enough" mechanism for the MPI_INIT-set-paffinity logic to determine
whether it should set affinity itself or not.

-- 
Jeff Squyres
Cisco Systems