Re: Changing the default 32-bit x86 arch for Fedora 12

[Adam Williamson <awilliam redhat com>]

On Mon, 2009-06-15 at 19:50 -0400, Bill Nottingham wrote:
> drago01 (drago01 gmail com) said: 
> > > Way back when in February [1], FESCo decided that for Fedora 11, i586 would
> > > be the default architecture, and for Fedora 12, it would be some variant of
> > > i686. It's time to follow through on that action item.
> > 
> > Moving to i686 is fine, non i686 chips are mostly dead (but the
> > perfomance gain from moving to i686 from i586 is questionable at
> > best).
> 
> ... how so? It's consistently 1-2% in reasonable benchmarks (real-world
> code, albeit cpu-specific).

Dan of Dan's Data has a rule of thumb I've always found sensible, which
is that any performance increase less than 5% is not worth putting
yourself to any kind of trouble for.

Has anyone benchmarked i686+SSE2 vs. i686 yet? It would seem a
prerequisite for such a controversial proposal. And in general-purpose
apps, not stuff that's known to benefit from it like media encoding
(which we have ways to handle without stuffing up the entire distro for
slightly old hardware).

-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Fedora Talk: adamwill AT fedoraproject DOT org
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