で、結局この問題は未解決のままいくのね、、、。< 8.0R

NOTE TO PEOPLE WHO THINK THAT FreeBSD 8.x IS SLOW ON IA64 OR SUN4V:
For ia64 the INVARIANTS and INVARIANT_SUPPORT kernel options
were left in the GENERIC kernel because the kernel does not
work properly without them. For sun4v all of the normal kernel
debugging tools present in HEAD were left in place because
sun4v support still needs work to become production ready.