machdep.cpu_idle_hlt and SMP perf?

[Yar Tikhiy]

Here is my own observation related to this topic:

With machdep.cpu_idle_hlt=1, both CURRENT and RELENG_6 inside MS
Virtual Server 2005 show bogus CPU utilization, e.g., in top(1):
the idle thread takes ~130% CPU (sic) and the clock thread takes
another 40% CPU; the interrupt time is 20-30% while the system is
idle.  Setting machdep.cpu_idle_hlt=0 makes the CPU stats look sane.

All this must be a bogosity in MS Virtual Server, but anyway
machdep.cpu_idle_hlt is a knob to try when things get weird :-)

-- 
Yar