Messages in this thread | | | Date | Fri, 01 Apr 2011 07:38:23 -0700 | From | Arjan van de Ven <> | Subject | Re: cpuidle asymmetry (was Re: [RFC PATCH V4 5/5] cpuidle: cpuidle driver for apm) |
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On 4/1/2011 1:15 AM, Dipankar Sarma wrote: > On Fri, Apr 01, 2011 at 12:09:25AM -0400, Len Brown wrote: >>>> Moorestown is already an example of an asymmetric system, >>>> since its deepest c-state is available on cpu0, but not on cpu1. >>>> So it needs different tables for each cpu. >>> wtf are these hardware guys smoking and how the heck are we supposed to >>> schedule on such a machine? Prefer to keep cpu1 busy while idling cpu0? >> they are smoking micro-amps:-) >> >> S0i3 on cpu0 can be entered only after cpu1 is already off-line, >> among other system hardware dependencies... >> >> So it makes no sense to export S0i3 as a c-state on cpu1. >> >> When cpu1 is online, the scheduler treats it as a normal SMP. > Isn't S0i3 a "system" state, as opposed to cpu state ?
it's misnamed. it's a C state to the OS.
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