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I have installed Ubuntu 11.04 and battery life decreased by 2 times. Powertop documentation says that there should be 3 wakeups per second, I have 800-900. I think it's very strange because I didn't touch any settings except for disabling nvidia graphic card. enter image description here How can i improve battery life?

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ath9k is a wifi driver. Was any program using the wifi connection at the time? Do you see the same numbers if you turn off the wifi connection? – Gilles Aug 21 '11 at 17:44
with wifi disabled wakeups decreases till 200-400 and ath9k is not in the list – Sergey Aug 21 '11 at 17:49
up vote 2 down vote accepted

Your problem is Chrome: Chromium Generates HUGE numbers of CPU wakeups and uses massive amounts of power (Chromium is the community version of Chrome)

Change to other browser.

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Ah, good to know. What other browser do you suggest? In my experience Firefox takes a lot more CPU to render a page, so in addition to being slower, it uses more power for rendering. My gut feeling is that Firefox may still be more power-efficient, but it would be worth measuring. – Gilles Aug 21 '11 at 21:26
Firefox has better results than Chrome in the bug report. In Phoronix the results are the opposite phoronix.com/…. Depends of the number of open tabs. I use Firefox7 in my netbook and the performance/consumption is very good (400 open tabs). A tip is use Panorama and other is change the preference "browser.sessionstore.max_concurrent_tabs" to 0. – Rufo El Magufo Aug 21 '11 at 21:53
And yes, Firefox will be more efficient and fast because to the actual works in GPU rendering. – Rufo El Magufo Aug 21 '11 at 21:55

It is telling you that "SignalSender" is responsible for most of the wakeups. Shut down that program.

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