Well it’s hardly ground breaking, in fact it’s been on every laptop ever probably, but after finally replacing my broken battery I can now run my laptop without it being plugged in. (Yay) This also makes the power statistics and power management functions in Ubuntu infinitely more relevent.
Within minutes of running Ubuntu 12.04 Precise Pangolin with the new battery I noticed a problem though.
The power statistics window turns blank and you can’t see any stats. Useless and frustrating! Further investigation reveals that its only if you close the window down using a method other than the ‘Close’ button (bottom right), does subsequent power statistics views appear blank.
After having a mind-melt with the trusty Google source, I dug up this official Ubuntu bug report confirming that it was indeed a known bug in Ubuntu’s latest Precise Pangolin. #Sigh
It looks like the power statistics window, actually called the gnome-power-statistics process, doesn’t terminate properely, causing subsequenct calls to it to behave incorrectly. Thankfully there’s a proven work around, other than using the close button (bottom right), a kill command from a terminal window will shut down the process allowing for future windows to be opened without appearing blank.
Fixing the blank Gnome power statistics window
When you’re stuck with a blank power stats’ window, open up terminale with CTRL+ALT+T.
Execute the following:
sudo ps aux | grep gnome-power
You should see some results like the screenshot below:
Now if you’re suffering with the bug mentioned in this article, you should hopefully see the words ‘gnome-power-statistics‘ on the right hand side, this means the process is also still running.
Now execute the following:
sudo kill XXX
Where XXX is the first group of digits on the line ending gnome-power-statistics from your previous command, in this example it’d be 3152 (shown between my name and the 2nd group of digits, 1.9).
What you’re doing here is telling the computer at a very low level that you want the process, with the ID of 3152, the one causing trouble, to stop being handled by the kernal. This I believe works in roughly the same way as Window’s Close Task function does, if that’s your background in computing.
You should now be able to open the power statistics window again normally, however make sure you close it down using the provided button, that is until this is patched correctly.
If this helps, please let me know.
Also if you’re experiencing this power window problem in another version of Ubuntu, especially 11.10, please let me know via the comments below.