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CPUSPEED always set the cpu frequency on demand ...

This is quite good, but I want that if the AC Adapter is connected, then we go in "performance" mode, else back to "ondemand" !

While ACPID uses events, we can easily use them to manage cpuspeed to increase or decrease the frequency of processor(s).

1) Create a file named "ac_adapter.conf" in "/etc/acpi/events", and will contain:

Code: Select all

event=ac_adapter
action=/etc/acpi/actions/ac_cpu.sh


This will trigger the event when AC Adapter is plugged in or off.

2) Create a file named "ac_cpu.sh" in "/etc/acpi/actions", and write:

Code: Select all

#!/bin/bash
ac_state=`cat /proc/acpi/ac_adapter/ADP1/state`
if [[ "$ac_state" =~ "on-line" ]] ; then
        echo "performance" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
        echo "AC Power Connected - Sent SIGUSR1 signal to cpuspeed for getting a fast static CPU"
else
        echo "ondemand" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
        echo "No AC Power Connected - Sent SIGHUP signal for going back to dynamic CPU speed"
fi


"/proc/acpi/ac_adapter/ADP1/state" may vary for you (eg. "/proc/acpi/ac_adapter/AC/state")

This script will be called whenever an action is made to AC Adapter !

3) "/etc/init.d/acpid restart" to make changes effective