STI, HLT in acpi_cpu_idle_c1

Matthew Dillon dillon at
Tue Jun 22 21:34:30 GMT 2004

:On Thursday 17 June 2004 07:33 pm, Matthew Dillon wrote:
:>     It kinda sounds like ACPI has bokered the other cpus.  I'm not sure
:>     why one would even *want* to use ACPI to idle down Xeon's in an MP
:>     system, actually :-)
:Power and heat savings.
:John Baldwin <jhb at>  <><

    All well and nice, but if you want power and heat savings you don't 
    purchase a big honking SMP box in the first place.

    This sounds like a disaster waiting to happen to me.  ACPI barely works
    on UP systems, there is no way I would ever trust it to properly HLT or
    otherwise screw around with the cpu timing on an SMP system.  HLT is
    plenty good enough.  IMHO this type of feature is not something that
    should be turned on by default on SMP.

					Matthew Dillon 
					<dillon at>

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