Quote Originally Posted by yotambien View Post
You have the performance benchmarks in the next page of that article.
Well, in some tests -O3 loses to -O2, but very slightly. But this is a test from a year ago and I can't even find which version of Gcc was used, nor can I see if it was done on 32bit or 64bit. I test alot of packages routinely (Blender, p7zip, Handbrake, Dosbox, Mame etc) with -O2 and -O3 and O3 comes out on top.