In article <457D353B.7010902@Gravier.org>,
Gilles Gravier  <Gilles@Gravier.org> wrote:
>OK... I didn't want to go into to much detail, which is why I left it at 
>that simple explanation.
>
>An OS like Solaris will give the same performance levels in 64 bit mode 
>and in 32 bit mode, in average (some things are faster, some slower). 
>Windows (but we all knew that in advance) sucks in 64 bit mode. Linux, 
>it depends a lot on what you are doing. NetBSD, I haven't tried.
>
>So yes... your milage may (will) vary. But I'm ready to bet my shirt 
>that your machine will NOT be faster in 64 bit mode than in 32... People 
>don't chose 64 bit mode over 32 for performance, but for capacity.
>

Oh, but you discount the fact that you get more registers in 64 bit mode...
I find that for most things 64 bit mode is faster (Linux and Win64). Solaris
does not count because most of the userland is 32 bit still.

christos