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powertop is a tool provided by Intel to enable various powersaving modes in userspace, kernel and hardware. It is possible to monitor processes and show which of them are utilizing the CPU and wake it from its Idle-States.


You can obtain the latest stable version via Pacman:

# pacman -S powertop

Alternatively, there is a newer, more sophisticated version available from the AUR.


powertop suggests a few methods to reduce the power consumption further, you may want to apply them automatically at boot, e.g. by putting them into rc.local.

noatime mount option

See Fstab.


echo 1 > /sys/module/snd_ac97_codec/parameters/power_save


Blacklist the hci_usb module if the driver is loaded automatically.

CPU scaling

To activate the ondemand CPU scaling governor for all CPU's:

for i in `find /sys/devices/system/cpu/*/cpufreq/scaling_governor`; do echo ondemand > $i; done;

CPU scheduler

echo 1 > /sys/devices/system/cpu/sched_mc_power_savings

Intel HDA

echo 1 > /sys/module/snd_hda_intel/paramters/power_save

Laptop mode

echo 5 > /proc/sys/vm/laptop_mode

NMI watchod

echo 0 > /proc/sys/kernel/nmi_watchdog

Runtime Power Management

for i in `find /sys/devices/*/power/control`; do echo auto > $i; done;

SATA Active Link Powermanagement

echo min_power > /sys/class/scsi_host/host0/link_power_management

USB autosuspend

for i in `find /sys/bus/usb/devices/*/power/level`; do echo auto > $i; done;
for i in `find /sys/bus/usb/devices/*/power/            autosuspend`; do echo 2 > $i; done;

=== VM writeback time To set the dirty writeback time to 15s, run:

echo 1500 > /proc/sys/vm/dirty_writeback_centisecs

Wake on LAN

To disable Wake on LAN:

ethtool -s eth0 wol d

Wireless powersaving

iwconfig wlan0 power on
Note: Kernel options are not mentioned.