Re: RFC: building numpy against OpenBLAS.

[Mark H Weaver <mhw@netris.org>]

Mark H Weaver <mhw@netris.org> writes:

> Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de> writes:
>
>> Ricardo Wurmus writes:
>>
>>> 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.
>>>
>>> We currently do not have a working OpenBLAS on MIPS, so the attached
>>> patch selects OpenBLAS as an input only when not on MIPS.  Some
>>> additional configuration happens only unless "atlas" is among the
>>> inputs.
>>
>> If there are no objections I'd like to go ahead and push this patch to
>> build numpy with OpenBLAS.  From the comments I gather that it's not as
>> controversial a change as I suspected.
>
> I think we should go ahead and switch to OpenBLAS on _all_ platforms,
> not just on MIPS.  Were there any objections to that?  If not, I'd
> advocate just doing it.

Libreoffice depends on python2-numpy, so if we don't switch to OpenBLAS
on all platforms, then we cannot offer binary substitutes for
Libreoffice.

Also, the persistent build failures of python-numpy on Hydra are
probably due to its use of ATLAS, when ALTAS is built on a different
build slave than python2-numpy.

So, at this point we have several strong incentives to phase out the use
of ATLAS.

      Mark