[HEADSUP] Atlas changed libraries

[Susi Lehtola]

On Sun, 22 Sep 2013 20:27:52 +0100
"Richard W.M. Jones" <rjones at redhat.com> wrote:
> > However, ATLAS still has different flavors for different CPUs (e.g.
> > 3dnow, sse, sse2, sse3 etc). I'm not sure if this can be easily
> > handled with alternatives.
> 
> Grrrr.
> 
> Please don't [to ATLAS upstream, not Susi] do this.  It breaks all
> sorts of scenarios, especially virtual machine migration or simply
> moving hard disks from one physical machine to another.
> 
> Arrange your code so it chooses the best available routines when the
> program starts up, and compile every feasible alternative into the
> binary.  Or use kernel vdso/user-helper functions when that is
> applicable.

I might mention that OpenBLAS (successor to GotoBLAS) is in Fedora,
which is often 2x faster than ATLAS. But, it's only available on ix86
and x86_64. It does have runtime CPU detection, though for the 20-odd
CPUs supported.
-- 
Susi Lehtola
Fedora Project Contributor
jussilehtola at fedoraproject.org