Re: -mm -> 2.6.13 merge status

From: Erik Slagter
Date: Wed Jun 22 2005 - 05:57:43 EST

On Tue, 2005-06-21 at 09:07 -0400, Arjan van de Ven wrote:
> On Tue, 2005-06-21 at 13:35 +0100, Alan Cox wrote:
> > On Maw, 2005-06-21 at 07:54, Andrew Morton wrote:
> > > CONFIG_HZ for x86 and ia64: changes default HZ to 250, make HZ Kconfigurable.
> > > Will merge (will switch default to 1000 Hz later if that seems necessary)
> >
> > This has been in Fedora for a while. DaveJ can probably give you more
> > info. From own testing 100Hz is how far down you want to go to avoid
> > random clock slew on laptops and to see power improvements.
> actually 250Hz is a not so fun value. 300 is a lot nicer (multiple of
> both 50Hz and 60Hz and thus covers most TV standards)

Sorry, the ITU-R "M" standard specifies 30000/1001 frames (60000/1001
fields) per second, that's close to 30/60 but not the same. Now please
please don't make use run HZ = (60000/1001 * 5) or similar ;-)

BTW it seems to me that power management using C2/C3 states will work
much more efficiently with a lower HZ because the chipset/processor will
be a larger percentage of the time in c2/c3 mode, right?
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