A small app of questionable value (myself I use it to throttle the CPU when I perceive it
is getting too hot). At the moment the code is optimized for a dell laptop but should work
on most ACPI systems.
Supports changing cpu speed via performance (Intl's enhanced speedstep in
Centrino/Pentium M cpus) as well, via the -p command line option. This is good for
saving energy while on batteries and it can also avoid fan noise.
It also features automatic, dynamic downclocking/throttling depending on the cpu
temperature. This can be useful to avoid fan noise. To enable this feature, simply
run wmthrottle with the -t <temperature> option and give it a certain temperature
threshold. Starting at this threshold, it will change performance/throttle states.
This is dynamic, i.e. a higher temperature will result in a lower clock speed
(or higher throttling).
The temperature threshold depends on the machine you use it on and on workload.
The machine it was tested on (Acer TravelMate 800) requires a
threshold of 49/50 degrees (Celsius) when having 100% cpu usage to keep the cpu fan
from turning on.
Note that although the numbers above are in Celsius, this feature should work with
Fahrenheit as well. Simply check /proc/acpi/thermal_zone/THRM/temperature to see
if your acpi is set to use Celsius or Fahrenheit.
When the -t switch is set, wmthrottle will change cpu performance/throttling
states every one degree. Example: You start wmthrottle with -t 49, which means
that it will change from state 0 to state 1 when the cpu is at 49 degrees,
and will change from state 1 to 2 when the temperature increases by 1 degree,
i.e. at 50 degrees, and so on.
If your setup requires a different temperature delta value, e.g. when your
system is using Fahrenheit, you can set this value using the -e switch.
You will probably have to plain with both the -t and the -e switches since
all computers are different.
Once you have started wmthrottle, change throttle/performance states by
clicking on state numbers.
If started with the -t <temperature> option, clicking on the [T] toggles
dynamic performance/throttle changes. If you turn it off, you can also choose
states manually again.
Clicking anywhere else will toggle the back light.
If you want to use wmthrottle with a windowmanager other than windowmaker, the
-bw (--broken-wm) flag will probably be your friend.
wmthrottle certainly needs to be run as root. To always run it as root, simply set the
setuid bit on wmthrottle after installing:
# chmod u+s wmthrottle
This means that wmthrottle is always run by whoever owns it (root in this case),
no matter who started it.
Also remember that playing around with your CPU etc can be a bad thing so saying
standard I take no responsibility for damage to your machine disclaimer applies.
