Re: 686x for Fedora Core

[Peter Backlund <peter backlund home se>]

Ed wrote:
> Are there plans in the near future to introduce Fedora Core compiled for 686 
> processors?

(Almost) all rpms in FC are built with -march=i386 -mpcu=i686, meaning 
that they are optimised for 686 but will run on all 386 hardware. 
Certain key packages, such as glibc and kernel, are built for specific 
architectures, i.e. -march=athlon or -march=i686. That's being done in 
the areas where the largest benefits are made.

In general, I'd say no one has been able to prove that compiling each 
and every application with aggressive optimisation and/or architecture 
specific instructions give any measurable speed improvements. There are 
several compiler experts on this list that can explain why.

That said, if anyone can point to a package that would benefit a lot
(more than 5%) from -march, I'm all for including that in FC. But show 
the numbers, no "man, -O3 made KDE so much 'snappier'!" stories :-)

/Peter