Lennert Buytenhek writes:
 > On Sat, Sep 26, 2009 at 09:53:55PM +0200, Mikael Pettersson wrote:
 > 
 > > The power button on the n2100 apparently does not generate
 > > an interrupt when pressed, so the board support code sets
 > > up a periodic timer to sample it.
 > > 
 > > This timer operates at 10 Hz, which makes it the third worst
 > > cause of timeouts in my kernel when idle.
 > > 
 > > 10 Hz seems excessive, so this patch adds a compile-time option
 > > to reduce the polling frequency to 1 Hz.
 > 
 > How much power does this actually save?

I have no way of measuring that, unfortunately.