Bug 23871 - [FR] march=i486 by default for i586 repo
Summary: [FR] march=i486 by default for i586 repo
Status: NEW
Alias: None
Product: Sisyphus
Classification: Development
Component: rpm-build (show other bugs)
Version: unstable
Hardware: x86 Linux
: P3 enhancement
Assignee: placeholder@altlinux.org
QA Contact: qa-sisyphus
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2010-08-10 18:30 MSD by Michael Shigorin
Modified: 2012-12-22 19:41 MSK (History)
9 users (show)

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Description Michael Shigorin 2010-08-10 18:30:22 MSD 
glibc authors recommend to avoid using i586-specific optimization for i686+ since these processors are quite different in architecture from pure i586 -- e.g. three pipelines instead of two perform better with one command stream instead of two:

http://git.altlinux.org/people/ldv/packages/?p=glibc.git;a=blob;f=sysdeps/i386/i686/Implies

Is it reasonable to "downgrade" optimization aiming at higher performance of legacy/lightweight systems?
Comment 1 Jeff Johnson 2012-01-03 02:45:23 MSK 
tracked at https://bugs.launchpad.net/rpm/+bug/911012