Re: system freezes for 0.2 to 0.5 seconds when reading /proc/acpi/thermal_zone/THRM/temperature

[Andrew Morton <akpm@osdl.org>]

Florian Engelhardt <flo@dotbox.org> wrote:
>
> Hello,
> 
> first of all, sorry for the long headline.
> second:
> Every time, i try to do the following:
> cat /proc/acpi/thermal_zone/THRM/temperature
> the whole system looks up for a short period of time (something about
> 0.5s). realy everything, video and audio encoding, mouse and keyboard
> input, firefox playing a flash animation, ...
> I am also getting the following:
> Losing some ticks... checking if CPU frequency changed.
> 
> maybe these two things are belonging to each other.
> 
> I am using a 2.6.12-rc3-mm1 kernel on a amd64 with a nvidia nforce4
> mainboard.

It might help if you were to generate a kernel profile:

readprofile -r
for i in $(seq 10)
do
	cat /proc/acpi/thermal_zone/THRM/temperature
done
readprofile -n -v -m /boot/System.map | sort -n +2 | tail -40