Arch Linux

angelo

Member

Registered: 2015-12-28

Posts: 40

powertop wrong attribution?

I have a minor issue (no impacting any functionality), but which is preplexing me for a while now.

Looking at power consumption from powertop, it claims that wireless is taking up 10.3W, while the total  discharge is only 6.57W: clearly these claims are not consistent (see below).  Moreover, the screen backlight is not showing at all, and should be the single largest power draw.  It seems that powertop is either attributing the backlight draw to the network interface, and/or is incorrectly measuring both. In the past the backlight did show, and network interface showed as much lower. Not sure when this changed.  I am not sufficiently familiar with these matters, and do not know where powertop gets the information.

This is on a dell XPS-13 9350, with a faulty battery (vastly reduced capacity at 7 months, but otherwise functional). 

PowerTOP 2.8      Overview   Idle stats   Frequency stats   Device stats   Tunables                                     

The battery reports a discharge rate of 6.57 W
The estimated remaining time is 1 hours, 41 minutes

Summary: 409.0 wakeups/second,  4.1 GPU ops/seconds, 0.0 VFS ops/sec and 13.6% CPU use

Power est.              Usage       Events/s    Category       Description
  10.3 W      0.2 pkts/s                Device         Network interface: wlp58s0 (brcmfmac)
  114 mW    106.3 ms/s     246.6        Process        firefox
 21.5 mW      1.1 ms/s      18.3        Process        xfwm4 --display :0.0 --sm-client-id 295046196-8f9c-4a62-a07d-9107db890668
 7.41 mW     10.1 ms/s       7.3        Process        /usr/lib/xorg-server/Xorg -background none :0 vt01 -nolisten tcp -novtswitc
 2.66 mW      2.9 ms/s       7.0        Process        /usr/lib/xfce4/panel/wrapper-1.0 /usr/lib/xfce4/panel/plugins/libxfce4power
 2.32 mW      2.2 ms/s      28.1        Timer          hrtimer_wakeup
 2.14 mW      1.8 ms/s      14.4        Process        thunderbird
 1.82 mW    602.0 us/s       5.4        Process        /usr/bin/python2 -O /usr/share/wicd/gtk/wicd-client.py --tray
 1.55 mW      1.9 ms/s       7.2        Process        /usr/bin/python2 -O /usr/share/wicd/daemon/wicd-daemon.py --no-daemon
 1.11 mW    685.7 us/s      24.6        Timer          tick_sched_timer
 1.04 mW    152.0 us/s       0.6        Process        xfce4-terminal --geometry=80x23 --display :0.0 --role=xfce4-terminal-146023
  846 uW      1.2 ms/s      0.00        Process        /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --sys

Last edited by angelo (2016-08-25 20:53:29)