Bill Nottingham wrote:
Warren Togami (wtogami@redhat.com) said:
This is a silly notion. Atom requires code to be built entirely differently from all modern processors in order to get maximum performance. Code must be optimized for in-line performance. Atom target support hasn't even hit gcc-4.4 yet.
Interestingly, using the parts of OpenBench that can actually be cajoled to build and run correctly (why are benchmark suites such pain?)... the best option for atom is -march=i686 -mtune=generic. Tuning for i586 (the previous in-order processor) doesn't actually help.
-march=i686 is better than i586, but is it the best. I though -march=prescott was optimal for atom?
Also, -march=i686 was a win over -march=i586, in general, in testing across Atom, Core2Duo, and a Athlon64, although not a particularly significant one.