On 11.11.2009 17:53, Andreas Radke wrote: > Am Wed, 11 Nov 2009 17:44:53 +0100 > schrieb Dieter Plaetinck <dieter@xxxxxxxxxxxx>: > > >> On Wed, 11 Nov 2009 17:18:12 +0100 >> Sven-Hendrik Haase <sh@xxxxxxxxxxxxx> wrote: >> >> >>> You will probably see the >>> opposite of what you saw in the VMs. Especially for video encoding, >>> x86_64 will be noticeably faster. >>> >> why is that? >> >> > > should be because of SSE+SSE2 extensions that are included in our > default compiler flags that are not used in i686. > > -Andy > > I've been searching for info on that but so far I couldn't find anything. Usually, SSE instructions flags are enabled specifically in the Makefiles of the programs that actually make use of them. They are not universally enabled in every compiled program by default (according to the optimizations turned on by -O2). Can you elaborate what you mean? Why are they not used on i686?
