Arch Linux

dbacc

Member

Registered: 2014-09-25

Posts: 120

Power consumption of network interfaces

I'm experiencing some problems with the power consumption of my network interfaces.

This is the output of powertop when the system is in idle and a few tabs of chromium are open.

  3.43 W      0,0 pkts/s                Device         Network interface: enp0s25 (e1000e)
  2.93 W     13,2 pkts/s                Device         Network interface: wlp3s0 (iwlwifi)

1.)
I have no network cable plugged into my LAN port.
Issuing

systemctl stop netctl-ifplugd@enp0s25.service

and

ifconfig enp0s25 down

removes the ethernet interface from powertops consumption list.

Is this expected behavior?

2.) Is 3W a normal value for the wifi card when more or less in idle? power_save is set to yes.

Mortimer Houghton

Member

Registered: 2014-09-28

Posts: 89

Re: Power consumption of network interfaces

For the first, see if wake-on-lan is active:

# ethtool interface | grep Wake-on

Supports Wake-on: pumbag
Wake-on: d

That is what it would look like deactivated.  If it shows something other than "d", it is likely your card is powered on waiting for packets. If so, try using udev rules to disable wake-on-lan (Wake-on-LAN - Udev).  Just change the example from "wol g" to "wol d" to disable.

For the second question, that is going to depend on your wireless adapter.  Older adapters can possibly use that much power, since they don't have as many power saving features as newer cards.

dbacc

Member

Registered: 2014-09-25

Posts: 120

Re: Power consumption of network interfaces

Ethtool shows that WoL is deactivated, so that's probably not the issue.

My wireless adapter is Intel Corporation Dual Band Wireless-AC 7265. Is that considered old?