em forwarding performance (was Proposed 6.2 em RELEASE patch

[Divacky Roman]

On Sat, Nov 25, 2006 at 05:22:16AM -0600, Matthew D. Fuller wrote:
> On Sat, Nov 25, 2006 at 09:36:05AM +0100 I heard the voice of
> Divacky Roman, and lo! it spake thus:
> >  
> > hm.. now I am confused. the rule is that having I586_CPU improves
> > performance because optimized bzero/bcopy is included (its not
> > included if you only have I686_CPU).
> 
> Haven't we been by this before?  It's not included even if you have
> I586_CPU either.
> 
> See src/sys/i386/isa/npx.c, line 432:
> 
> #ifdef I586_CPU_XXX   <--------
>                 ^^^
> 
> This has been disabled since r1.95, in 2001 (in 5-CURRENT days).
> There may be SOMETHING about including I586_CPU that speeds things up,
> but it ain't that.

the log says:

People are still having problems with i586_* on UP machines and SMP
machines, so just hack it to disable them for now until it can be fixed.

noone has been able to step up and fix that? for more then 5 years?
huh.. I guess thats quite low hanging fruit worth shoting down..