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From: Gleb Natapov (glebn_at_[hidden])
Date: 2007-06-14 06:42:53

On Wed, Jun 13, 2007 at 10:01:20PM -0400, Patrick Geoffray wrote:
> Jeff Squyres wrote:
> > Let's take a step back and see exactly what we *want*. Then we can
> > talk about how to have an interface for it.
> I must be missing something but why is the bandwidth/latency passed by
> the user (by whatever means) ? Would it be easier to automagically get
> these values by probing the hardware or have the BTL do an educated
> guess ? You can figure out at runtime the link rate of an eth device for
> example. You would want have a complicated way to force any value, but
> the default should be invisible, no ?
That what happens for openib today. Configure bandwidth to 0 and BTL
automatically will figure out HW speed, but sometimes you want to
override it.