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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-03-21 13:10:16

On Mar 21, 2007, at 10:24 AM, Donald Kerr wrote:

> Case: A btl parameter is given a default setting and at some later
> point is potentially adjusted depending on the number of peers.
> Now if the MPI user sets this same parameter I don't won't to
> overright what they have set, or at least I would like to warn them
> before doing so.

Gotcha. Right now, there's no way to check this (i.e., what "level"
an MCA param was set from). I see two options for going forward:

1. Add an API call to check what level a given MCA param is currently
resolved from (probably return some kind of enum?).

2. Don't use the MCA param API but rather keep your own state (e.g.,
a global with the default, another with the adjusted value derived
from the number of peers, etc.) and do your own comparisons to see if
the value was changed.

#2 is workable today, but obviously more work for you. #1 is a
better long-term solution. It wouldn't be too much work to do, but I
unfortunately do not have the cycles to do it at the moment. I'd be
happy to point you in the right direction, if you want...

Jeff Squyres
Cisco Systems