It's interesting to see that the Altivec version of pmap_copy_page
   (vcopypage) is so much faster than the non-Altivec version.
   Given that pmap_remove is 32us/call on the G4/400 and 63us on the
   604ev/180 (roughly scaling with CPU speed), the difference between
   19us for vcopypage and 136us for pmap_copy_page is amazing.  That's
   over 3 times as fast as you'd except pmap_copy_page to be on the G4.


do you use any of the ds* altivec insructions?