cpuspeed enables you to dynamically change the CPU speed of a processor through the ACPI daemon. I find it useful only for my laptop, and only when I do not have AC power. The default configuration is very annoying, which monitors the system's idle percentage and reduces or raises the CPU's clock speed and voltage accordingly to minimize power consumption when idle (theoretically). The configuration file is now located in /etc/sysconfig/cpuspeed. Edit the file using sudo:
~>
sudo nano
/etc/sysconfig/cpuspeed
Perform a search for the "GOVERNOR=" line.
Add the following:
GOVERNOR=performance
Next scroll down to the "# Add your favorite
options here" line and make sure that the line just below
it is commented out. This will remove the "-r" option
(restores previous speed on program exit), which will allow the system
to be governed by load, AC power, and temperature management only. To
do this, add the following:
OPTS="$OPTS
-i 2 -C"
The "-i 2"
option
changes the default response time to 2/10's of a second from 2 seconds
and the "-C"
option will ensure that the CPU runs at maximum speed when AC
power is connected and only at lower speeds if on battery
power or if the temperature of the processor is too high. Finally,
uncomment the last two "OPTS"
lines to allow cpuspeed
to actually check the state of the AC adapter and system
temperature:
OPTS="$OPTS
-a
/proc/acpi/ac_adapter/*/state"
OPTS="$OPTS -t /proc/acpi/thermal_zone/*/temperature 75"
Save and exit.
Now restart the
daemon:OPTS="$OPTS -t /proc/acpi/thermal_zone/*/temperature 75"
~>
sudo service cpuspeed
restart
You should see cpuspeed
stop
and restart:
Disabling
performance cpu
frequency
scaling:
[ OK
]
Enabling performance cpu frequency scaling: [ OK ]
As a final note, cpuspeed
finally has a man
page. Use it to determine the different options for the
daemon.Enabling performance cpu frequency scaling: [ OK ]