[Numpy-discussion] Use OpenBLAS for the binary releases?

[David Cournapeau]

On Tue, Nov 20, 2012 at 8:52 PM, Henry Gomersall <heng at cantab.net> wrote:
> On Tue, 2012-11-20 at 20:35 +0100, Dag Sverre Seljebotn wrote:
>> Is there a specific reason it *has* to happen at compile-time? I'd
>> think
>> one could do something like just shipping a lot of separate Python
>> extensions which are really just the same module linked with
>> different
>> versions of the library, and then
>>
>> if cpu_is_nehalem:
>>      import blas_nehalem as blas
>> elif ...
>>
>> I'm asking a question about whether this would work in principle, I
>> realize it would perhaps not fit that well in the current NumPy
>> codebase.
>
> I was wondering this in the context of a previous discussion. Could we
> not have an autotune module, that just runs a load of test scripts and
> picks the best library to link against?

You can't easily relink at install time, so what you want is pick up
the best library at runtime. It is more or less impossible to do this
in a portable way (e.g. there is no solution that I know of on windows
< windows 2008, short of requiring to install some dlls with admin
privileges).

cheers,
David