Re: Fw: [BUG 2.6.21-rc7] acpi_pm clocksource loses time on x86-64

From: Mikael Pettersson
Date: Fri May 04 2007 - 03:43:15 EST


On Thu, 03 May 2007 19:38:50 -0700, john stultz wrote:
> > So that slow acpi_pm on x86_64 seems to be connected w/ the idle loop.
> > I'm guessing the chipset halts the ACPI PM in lower C states. Do you
> > have any guesses as to what might differ between x86_64 and i386 ACPI
> > idle loops? Or might this be something different in what the BIOS
> > exports in x86_64 mode or i386 mode?
>
> Mikael,
> Just trying to dig a bit more through the acpi_processor_idle code.
> Could you run "cat /proc/acpi/processor/CPU1/power" and reply w/ the
> output?

Here's that file with the x86-64 kernel:

active state: C2
max_cstate: C8
bus master activity: 00000000
maximum allowed latency: 20000 usec
states:
C1: type[C1] promotion[C2] demotion[--] latency[000] usage[00107840] duration[00000000000000000000]
*C2: type[C2] promotion[--] demotion[C1] latency[010] usage[-1987043693] duration[00000000003044809185]

/Mikael
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