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Subject: Re: [hwloc-devel] 1.3.1 and 1.4rc1
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2011-12-13 12:02:55


Brice Goglin, le Tue 13 Dec 2011 16:41:08 +0100, a écrit :
> Le 13/12/2011 16:22, Jeff Squyres a écrit :
> >
> > I can't speak for GPUs, but I think the PCI information will be useful to know what devices are close to what PUs / NUMA nodes. That information can be used to make decisions about binding, for example (i.e., you want to be "close" to the specific PCI resources that you'll be using).
>
> In most cases, you don't need PCI support for this, you juste manipulate
> a cuda device, an ibv_device, a MX endpoint, ... and use one of the
> inline helpers to get the corresponding locality (a cpuset).

A problem I see there is that although you can write such helper for
Linux, nothing guarantees that it'll be so easy for other OSes. And you
need to rebuild the application when a bug gets fixed.

Samuel