Re: [REGRESSION] [Linux 3.2] top/htop and all other CPU usage

From: Michal Hocko
Date: Wed Nov 30 2011 - 05:12:28 EST


On Tue 29-11-11 23:51:16, Rafael J. Wysocki wrote:
> On Tuesday, November 29, 2011, Michal Hocko wrote:
> > On Tue 29-11-11 12:54:16, Artem S. Tashkinov wrote:
> > > > On Nov 29, 2011, Michal Hocko wrote:
> > > >
> > > > On Tue 29-11-11 13:31:56, Michal Hocko wrote:
> > > > > On Tue 29-11-11 11:38:47, Artem S. Tashkinov wrote:
> > > > [...]
> > > > > > $ grep . -r /sys/devices/system/cpu/cpuidle/
> > > > > > /sys/devices/system/cpu/cpuidle/current_driver:intel_idle
> > > > > > /sys/devices/system/cpu/cpuidle/current_governor_ro:menu
> > > >
> > > > Could you try with acpi_idle driver?
> > > > echo acpi_idle > /sys/devices/system/cpu/cpuidle/current_driver
> > >
> > > [root@localhost ~]# echo acpi_idle > /sys/devices/system/cpu/cpuidle/current_driver
> > > -bash: /sys/devices/system/cpu/cpuidle/current_driver: Permission denied
> >
> > It seems that this is cannot be set in runtime:
> > SYSDEV_CLASS_ATTR(current_driver, 0444, show_current_driver, NULL);
> >
> > Or maybe you need to boot with cpuidle_sysfs_switch. According to the
> > documentation you might be able to change the governor. I have no idea
> > whether this can help somehow but let's try that.
> >
> > I haven't found any intel_idle machine in my lab so far and all other
> > acpi_idle machines seem to work (or at least randomly selected ones) so
> > this smells like a major difference in the setup.
>
> I'm able to reproduce that with acpi_driver on one box, but not on demand.

And do you see the same thing (no idle/io_wait) updates?

>
> Thanks,
> Rafael

--
Michal Hocko
SUSE Labs
SUSE LINUX s.r.o.
Lihovarska 1060/12
190 00 Praha 9
Czech Republic
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