Re: [PATCH] i386 No Idle HZ aka dynticks 051221

From: Pavel Machek
Date: Tue Dec 27 2005 - 09:34:51 EST


On Út 27-12-05 00:27:12, Pavel Machek wrote:
> On Po 26-12-05 17:52:48, Theodore Ts'o wrote:
> > On Mon, Dec 26, 2005 at 09:38:06PM +0100, Pavel Machek wrote:
> > > Stupid IBM. I've seen it appearing/disappearing, but did not work out
> > > when.
> > >
> > > No-C4-on-AC is bad -- if you just disconnect AC and walk away, you are
> > > running without benefits of C4. Bad. Changing benchmarks depending on
> > > you booting on AC or battery also look nasty.
> >
> > The moment you disconnect AC, it C4 automagically appears. When you
> > reconnect to the AC mains, the C4 state disappears again, at least
> > from the listing displayed by /proc/acpi/processor/CPU0/power. So the
> > first issue you brought up isn't a problem.
>
> It does not seem to work like that here. I'm not sure what the exact
> rules are, but I know that I sometimes have C4 and sometimes not. I
> have C4 now, and it is used, even when I'm on AC power. Thinkpad
> X32.

Well, today it _does_ behave like Theodore described (slightly
different kernel, and I'm using power supply, not docking
station). Strange.

Pavel

--
Thanks, Sharp!
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/