Re: Status of X86_P4_CLOCKMOD?

[Johannes Stezenbach <js@linuxtv.org>]

On Sun, Feb 26, 2006, Dominik Brodowski wrote:
> On Sun, Feb 26, 2006 at 09:39:41PM +0100, Johannes Stezenbach wrote:
> > 
> > Do you have the numbers for a Pentium(R) 4 HT? (I couldn't find
> > anything substantial with google.) Especially C2 vs. C2 + throttling?
> > Because the way I remember having read somewhere, the idle
> > (C2) power consumption of the P4 is significantly higher
> > than with the Pentium(R) M.
> 
> Unfortunately, I do not have these numbers present. You can check the
> processor specification sheets at Intel's website, though.

Went to the Intel(R) website, searched for half an hour, found many
docs but none that gives useful information about this, gave up. :-(

> > > So: P4-clockmod style throttling only makes sense if either
> > > 
> > > a) the idle handler does not enter the Stop-Grant state (C2) efficiently, or
> > 
> > Maybe my previous mails were not clear enough: The goal is to
> > reduce idle power consumption (and by that fan noise). The PC
> > is running but is idle, e.g just listening for possible incoming
> > jabber messages or whatever.
> 
> Most probably, the idle handler can't make use of the Stop-Grant state (C2)
> here, so this is case a) noted above.

Hm.

Thanks,
Johannes