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Subject: Re: [OMPI users] CPU burning in Wait state
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2008-09-04 18:42:17


On Sep 4, 2008, at 4:35 PM, Eugene Loh wrote:

>> There are many alternatives to polling hard. One is to yield the
>> CPU if someone else is asking for it. Again, Open MPI has some
>> support for this today with the "mpi_yield_when_idle" variable.
>> Right? Might not be all of what someone wants, but the above
>> discussion just seems not to account for this. In any case, I
>> verified that it does do something useful in at least one case.

Yes, we do do that, as you verified. The main intent of that features
was to support oversubscribing (e.g., developing a parallel app on a
laptop or limited-processor desktop).

-- 
Jeff Squyres
Cisco Systems