PM utils power saving improvements - call for testing

Colin Ian King colin.king at
Tue Dec 13 15:15:53 UTC 2011

Hi there,

== Call for testing: pm-utils power saving improvements ==

PM utils power.d scripts control power management settings when a laptop 
is on mains or battery power. The power.d scripts currently attempt to 
optimize power savings when on battery power by adjusting settings such 
as audio and wireless power management, readahead and journal commit 
settings to name just a few.

The kernel provides mechanisms to put specific USB and PCI devices into 
lower power consuming states and with careful choice of the specific 
devices we can reduce the overall system power consumption by a few 
Watts depending on the types of devices installed on a laptop or netbook.

Initial analysis on a range of hardware has identified a set of devices 
(Bluetooth, Wireless, Ethernet, SD card readers) that can be put into a 
low power state and we are looking for volunteers to test some updated 
pm-utils power.d scripts. We are interested in two types of test:

1) Do these pm-util scripts save any power across a range of machines?

2) Does enabling these savings affect any device behavior?

A crowd-sourcing testing Wiki page has been created that describes how 
to test these updated pm-utils scripts and can be found at:


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