Re: [Fwd: libfreevec benchmarks]
Hi, Michel.
On Aug 21 2008, Michel Dänzer wrote:
> This may be interesting for those concerned about PPC vs. x86
> performance.
Ah, this is really interesting.
> Konstantinos Margaritis wrote:
> > Benh suggested that I made this more known, and in particular to
> > this list, so I send this mail in hope that some people might be
> > interested. In particular, I ran the following benchmarks against
> > libfreevec/glibc:
> >
> > http://www.freevec.org/content/libfreevec_104_benchmarks_updated
The results are really impressive.
This might explain my impression in a private mail to Charles Plessy
that my iBook G3 was quite faster under Linux than under MacOS X.
Apparently, MacOS X is *made* *for* altivec machines.
> > The OpenSuse guys even consider using it by default on the ppc port
> > even, but that's not final of course.
Really nice.
> > glibc integration _might_ happen if glibc developers change their
> > attitude (my mails have been mostly ignored).
This would be very welcome addition to glibc. Especially for the
"weaker" chips that don't have any vectorial part.
> > Last, I've also been working on a libm rewrite, though this will
> > take some time still. I've reimplemented most math functions at the
> > algorithm level, eg. so far, most functions achieve 50%-200% speed
> > increase at full IEEE754 accuracy (mathematically proven, soon to be
> > published online) without using Altivec yet,
This part about not using altivec is interesting, since I would like to,
say, be able to watch DVDs with my iBook and not have them drop so many
frames. Decoding theora videos is also quite CPU intensive... :-(
> > just by choosing a different approximation method (Taylor
> > approximation is pretty dumb if you ask me anyway).
What are you using, BTW? CORDIC?
Regards, Rogério Brito.
--
Rogério Brito : rbrito@{mackenzie,ime.usp}.br : GPG key 1024D/7C2CAEB8
http://www.ime.usp.br/~rbrito : http://meusite.mackenzie.com.br/rbrito
Projects: algorithms.berlios.de : lame.sf.net : vrms.alioth.debian.org
Reply to: