Athlon bug stomper: perf. results

On Wed, Sep 19, 2001 at 11:43:48AM -0700, Dan Hollis wrote:
> AFAIK noone has even tested it yet to see what it does to performance! Eg
> it might slow down memory access so that athlon-optimized memcopy is now
> slower than non-athlon-optimized memcopy. And if it turns out to be the
> case, we might as well just use the non-athlon-optimized memcopy instead
> of twiddling undocumented northbridge bits...

Ok. perhaps this will help:

System: AMD Duron 800Mhz Epox 8KAT3+ MB

I power cycled machine between tests:

Linux 2.4.9ac5 *without* althon bug stomper patch:

    oopes to death on boot.

Linux 2.4.9ac5 with athlon bug stomper patch:

Athlon test program $Id: fast.c,v 1.6 2000/09/23 09:05:45 arjan Exp $ 
clear_page() tests 
clear_page function 'warm up run'        took 19854 cycles per page
clear_page function '2.4 non MMX'        took 11991 cycles per page
clear_page function '2.4 MMX fallback'   took 11857 cycles per page
clear_page function '2.4 MMX version'    took 13666 cycles per page
clear_page function 'faster_clear_page'  took 4853 cycles per page
clear_page function 'even_faster_clear'  took 4819 cycles per page

copy_page() tests 
copy_page function 'warm up run'         took 19638 cycles per page
copy_page function '2.4 non MMX'         took 23855 cycles per page
copy_page function '2.4 MMX fallback'    took 24043 cycles per page
copy_page function '2.4 MMX version'     took 19550 cycles per page
copy_page function 'faster_copy'         took 10909 cycles per page
copy_page function 'even_faster'         took 11333 cycles per page

Linux 2.2.19:

Athlon test program $Id: fast.c,v 1.6 2000/09/23 09:05:45 arjan Exp $ 
clear_page() tests 
clear_page function 'warm up run'        took 14658 cycles per page
clear_page function '2.4 non MMX'        took 13254 cycles per page
clear_page function '2.4 MMX fallback'   took 13099 cycles per page
clear_page function '2.4 MMX version'    took 13005 cycles per page
clear_page function 'faster_clear_page'  took 4913 cycles per page
clear_page function 'even_faster_clear'  took 4887 cycles per page

copy_page() tests 
copy_page function 'warm up run'         took 19664 cycles per page
copy_page function '2.4 non MMX'         took 26431 cycles per page
copy_page function '2.4 MMX fallback'    took 26432 cycles per page
copy_page function '2.4 MMX version'     took 19537 cycles per page
copy_page function 'faster_copy'         took 11564 cycles per page
copy_page function 'even_faster'         took 11467 cycles per page

-- 
Brian Litzinger <[e-mail]>

    Copyright (c) 2000 By Brian Litzinger, All Rights Reserved