Another whirl with FreeBSD

[Gary Palmer]

On Thu, Oct 12, 2006 at 05:20:03PM +0100, Mike Bristow wrote:
> On Wed, Oct 11, 2006 at 01:13:27PM +0200, Oliver Fromme wrote:
> > Heinrich Rebehn wrote:
> >  > > [i386 vs. amd64]
> >  > Overhead ?? Would this mean that the 64 bit version will run slower?
> > 
> > It depends.  Most applications will run somewhat faster,
> > but there are cases where you might get a small slow-down.
> [snip]
> 
> Doesn't the increased number of registers available when running amd64
> really, really help when compared with the traditionally register-starved
> i386?

Except that you've made context switching more expensive as you have to
save/restore more data/registers. Possibly function calls inside the
code are also more expensive for the same reason. You also have to use
natively compiled binaries and a compiler that can take advantage of
the additional registers, and even then thats not a guarentee of
increased performance.  That will depend to a degree on the code being
compiled.

As with everything in life, there is a balance.  For some applications
64bits are either required (due to memory addressing issues, for example)
or offer some tangible benefit.  Other applications suffer.  YMMV. 
 
> I'm certainly of the opinion that plumping for amd64 over i386 is a sensible
> default.
> 
> -- 
> I don't play The Game - it's for five-year-olds with delusions of adulthood.
> 
> _______________________________________________
> freebsd-stable at freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-stable
> To unsubscribe, send any mail to "freebsd-stable-unsubscribe at freebsd.org"
> 
>