On Sun, 22 Sep 2013 20:27:52 +0100
"Richard W.M. Jones" <rjones(a)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(a)fedoraproject.org