Re: [eigen] Idea: BLAS backend

[Gael Guennebaud <gael.guennebaud@xxxxxxxxx>]

Goto blas is not small at all:
- libgoto2.a: 20MB
- libeigen_blas.a: 2.5MB

libeigen_blas is a complete BLAS interface built on top of Eigen.

Also GotoBlas or MKL have several limitations:
- not suitable  for ARM/NEON
- cannot control memory allocation of temporaries (blocks for level3
routines, and in some cases packing of strided vectors  for level2
routines)
- can we control the number of thread at runtime? I'm not sure
- no hybrid real-complex products
- only for foat, double, and their complex versions

That being said, it might still be interesting to add the possibility
to fallback to a BLAS lib when that's possible. Since our internal
product routines are quite similar to the BLAS ones,  that should not
be very difficult.

gael

On Thu, Feb 3, 2011 at 2:18 PM, Konstantin Tokarev <annulen@xxxxxxxxx> wrote:
>
>> I don't believe at all that code size would be an argument here. Being
>> a template library we allow the users to compiler only the code that
>> they want. By contrast, a binary library like GotoBLAS contains code
>> for all functions, for all 4 numeric types. It can't compete with us
>> on code size.
>
> I've implied static linking, of course :)
> However I haven't measured actual sizes, it was just a random idea
>
> --
> Regards,
> Konstantin
>
>
>