Subject: Re: [PATCH 0/3] cpu: idle state framework for offline CPUs.

From: Pavel Machek <[email-masked]>
Date: Mon, 10 Aug 2009 10:19:41 +0200

On Sun 2009-08-09 15:22:02, Rafael J. Wysocki wrote:
> On Sunday 09 August 2009, Pavel Machek wrote:
> > Hi!
> > 
> > > > Also, approaches such as [1] can make use of this
> > > > extended infrastructure instead of putting the CPU to an arbitrary C-state
> > > > when it is offlined, thereby providing the system administrator a rope to hang
> > > > himself with should he feel the need to do so.
> > > I didn't see the reason why administrator needs to know which state offline cpu
> > > should stay. Don't know about powerpc side, but in x86 side, it appears deepest
> > > C-state is already preferred.
> > > 
> > 
> > Agreed, deepest c-state is always best, there's no need to make it configurable.
> 
> Unless it doesn't work.

If it does not work, machine will not boot. We already have
max_cstate= kernel command line option to work around that...

									Pavel
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