[ltp] Sudden high power usage

Christos Papadopoulos linux-thinkpad@linux-thinkpad.org
Mon, 04 Feb 2013 08:10:50 -0700


Something happened to my X220 with F17 recently (kernel update?) and 
power usage has gone up significantly.

On battery, I see consumption as high as 25W!

Powertop reports the following top offenders (on AC, not battery):

Power est.              Usage       Events/s    Category       Description
   5.75 W     46.7%                      Device         Display backlight
   5.03 W     2757 pkts/s                Device         Network 
interface: wlan0 (iwlwifi)
   3.26 W      0.0 pkts/s                Device         Network 
interface: em1 (e1000e)

wlan0 power fluctuates between 5-7W. I am on a busy wireless, but is 
this reasonable?

I don't have a wired connection, yet the wired interface uses over 3W, 
sometimes as high as 5W!

This seems to happen (or get worse) after a suspend-resume cycle.

Any ideas?

Christos.