[R-SIG-Mac] daxpy performance with veclib

[Michael Spiegel]

Ah, thanks for the heads up.  It turns out that the problem is
somewhat worse than as you have described.  So not only is vecLib
single threaded on some of BLAS functions (I've noticed that dgemm is
multithreaded), but the vecLib single threaded implementation worse
than the single threaded reference implementation.  I'll follow your
suggestion and give ATLAS a try.  I had poor luck with goto BLAS, our
performance test suite was slower using that implementation.

On Wed, Oct 20, 2010 at 4:29 PM, Simon Urbanek
<simon.urbanek at r-project.org> wrote:
>
> Yes, that is a known problem (see R-SIG-Mac archives). vecLib fails to use multiple cores on Nehalem-based Mac Pros. If you use ATLAS directly it will work just fine - that's what we recommend on Mac Pros.
>
> Cheers,
> Simon
>