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I am running powertop in Ubuntu 10.04. It shows a horizontal bar near the top that displays something like:

Wakeups-from-idle per second : 723.6 interval: 10.0s

My question is, why is the background color on this line red, and on rare occasions blue? What do these colors mean? Unfortunately the man page does not explain this, neither does a quick Google search.

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up vote 1 down vote accepted

Below the state numbers, a bar shows how often the processor was awakened in one second (Wakeups-from-idle per second). The smaller the figure, the better. If you use the Gnome desktop, you can theoretically reduce this to three wake-ups per second, although realistically a value below 20 is pretty good. The color of the bar also indicates good and bad values: A bright red bar means that you really need to take some action; amber means an acceptable energy-saving situation.

enter image description here


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