From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Bavier <ericbavier@centurylink.net>
Subject: Re: RFC: building numpy against OpenBLAS.
Date: Fri, 22 May 2015 11:16:00 -0400 (EDT)
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To: Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>
Cc: guix <guix-devel@gnu.org>


----- Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de> wrote:
> python-numpy currently depends on Atlas, which means that it cannot be
> substituted with a binary built elsewhere.  OpenBLAS is an alternative
> to Atlas and the binary can be used on all supported CPUs at runtime.
> This makes it possible for us to make numpy substitutable.
[...]
> Anyway, I just wanted to post this here to ask for opinions.  Maybe this
> is a bad idea.  (In my case it makes sense not to use Atlas, because the
> compile-time tuning is useless when a shared store is used and clients
> use Atlas on machines other than the build host.)
> 

I would very much like to see OpenBLAS substituted for atlas whereever possible.  The runtime performance of OpenBLAS is quite a bit better than ATLAS.  I've seen e.g. OpenBLAS to be roughly 20% faster than ATLAS for GEMM calls on Sandybridge platforms.

`~Eric