Once upon a time, Bill Nottingham <notting(a)redhat.com> said:
- We don't really support i586 in any meaningful matter
What does this mean? Does Fedora not run on i586? Why was there a
mass-rebuild for i586 if it doesn't work?
- We are likely doing a mass rebuild for F-12 anyways, might as well
while we're doing it
That's a pretty poor justification.
- Atom is the only currently produced 32-bit x86 chip of note;
for what's currently available
There are also lots of other chips that people run 32 bit x86 code on.
I don't think Atom is a majority percentage of 32 bix x86 Fedora users
If you want numbers, I did some benchmarking of code  with
build options on a variety of processors, with the F-11 gcc code. All
of these results are relative to a F-11 baseline of "-march=i586
P4 2.4Ghz Athlon 3400+ Core2Duo E6850 Atom N270
march=i686/ -1.1% +2.0% +0.9% +0.6%
march=i586/ +0.3% -0.3% -0.2% +1.3%
march=i686/ -1.5% +1.2% +0.5% +1.7%
 gzip, bzip2, math simulation, mp3 encode/decode, ogg encode/decode
Okay, before I thought you said this was a "1-2% improvement across the
board", but now it is a 1% improvement on some CPU-intensive operations
on some CPUs (and a 1% performance hit on other CPUs).
How does this affect multilib on x86_64?
The justification for the i586 rebuild was that there hasn't been a
Fedora i386 kernel for years (so i586 was already required anyway).
This is the first time Fedora is proposing to throw out CPU support in a
long long time, and I find a minimal improvement on some targeted
benchmarks a poor justification.
It would seem to me that adding a few targeted Atom packages would be a
better use of resources (e.g. similar to openssl.i686).
Chris Adams <cmadams(a)hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.