Hello,
I would like to call people to volunteer on the yamt-idlelwp branch. It needs
some work on architectures. Things, which should be done:

1. Remove cpu_switch() and rework, if necessary, cpu_switchto().
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/arch/i386/i386/locore.S.diff?r1=1.45&r2=1.45.2.4

2. Implement MD idling. In x86 there is a simple "hlt" instruction. I do not
know how about other architectures.
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/arch/x86/x86/Attic/idle_machdep.c?rev=1.1.2.1

3. In some architectures (m68k, hppa, vax?), there are still MD
setrunqueue/remrunqueue (in yamt-idlelwp branch, these was renamed to
sched_enqueue/sched_dequeue) implementations.
These must be removed, and used only MI functions.

Currently done: i386, amd64
At this moment, all other architectures are standing.

Thanks!

-- 
Best regards,
Mindaugas
www.NetBSD.org