i686 optimization

[Matt Zimmerman]

On Wed, Jun 14, 2006 at 11:10:59PM +0100, Jack Wasey wrote:
> Pavel Roitberg wrote:
> >Gianmarco Leone wrote:
> >>Hi,
> >>
> >>considering that Dapper is LTS, couldn't Edgy be 686-optimized? 
> >Its not worth it -i686 does not have a consoderable performance impact 
> >for most programs.
> 
> So why not have -i686, -k7 etc for packages where it does make a 
> difference? We already do this for kernel and to some extent for libc6. 
> Compression libs are used often in the background, and some rendering or 
> 3d stuff would definitely benefit and be used if falling back when no 
> fancy graphics card is present. What else? Encryption libs?
> 
> Why not auto-detect processor type on install, and choose a handful of 
> key k7 686 or whatever other sub-arch packages?

Because the right way to do it, in the cases where it makes a worthwhile
difference, is to detect the CPU type at runtime and select the appropriate
code.

libssl, for example, already does this, as does libc6.  In the libc6 case,
the support is shipped in a separate package, but it's included on every
Ubuntu system and the appropriate choice is made at runtime.

-- 
 - mdz