Synopsis: SMP amd64 system exhibits excessive cpu shootdown IPIs

State-Changed-From-To: analyzed->feedback
State-Changed-By: ad@netbsd.org
State-Changed-When: Thu, 15 Nov 2007 21:10:02 +0000
State-Changed-Why:
It's actually a more general problem in that the amd64 pmap was
issuing far too many unnecessary shootdowns. That has been fixed,
and the shootdown code re-written to reduce overhead and improve
concurrency. 

I still notice "more" shootdowns happening than on i386 with a
standard kernel, but I believe that the problem should be (by
and large) fixed.