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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-07-09 16:11:57


On Jul 9, 2007, at 3:17 PM, Peter Kjellstrom wrote:

> Our new HP cluster has 25208 HCAs (Mellanox Arbel) but a new vendor-
> id... We
> have 0x1708 (presumably HP, hardware wise Cisco (Mellanox)) to add
> to the

Added in r15316; thanks for pointing it out.

> existing list in share/openmpi/mca-btl-openib-hca-params.ini that
> currently
> contains:
> # Mellanox 0x2c9
> # Cisco 0x5ad
> # Silverstorm 0x66a
> # Voltaire 0x8f1
>
> Somewhat related question 1: Is there a blessed way to map these
> ids back to
> strings?

Not via C API, no. But the IEEE OUI web page can be used to look up
these values:

     http://standards.ieee.org/regauth/oui/

> question 2: Is 1024 really the best MTU for DDR Arbel? I seem to
> remember this
> being 2048...

I *believe* that that value came from Mellanox, but I don't remember
offhand. But it could also be a "doesn't really matter either way"
issue. You might want to try both with your apps and see if there's
a performance difference. Let us know what happens.

-- 
Jeff Squyres
Cisco Systems