lkml.org 
[lkml]   [2011]   [Apr]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: cpuidle asymmetry (was Re: [RFC PATCH V4 5/5] cpuidle: cpuidle driver for apm)
From
Date
On Fri, 2011-04-01 at 00:09 -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:-)

Has anybody told them that pushing lots of logic into software generally
burns more amps because it keeps the thing running longer?

> 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.

Dipankar's reply seems to address this issue well.


\
 
 \ /
  Last update: 2011-04-01 16:05    [W:0.097 / U:0.496 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site