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

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Wednesday, November 30, 2011, Michal Hocko wrote:
> 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?

Actaully, I was wrong.  The box I'm seeing the issue on also has "none"
in /sys/devices/system/cpu/cpuidle/current_driver.  Sorry for the confusion.

Thanks,
Rafael