PowerTOP tool released; time to fix the wasted laptop power on fedora?

[Jesse Barnes]

On Sunday, May 13, 2007, dragoran dragoran wrote:
> On 5/13/07, Dominik 'Rathann' Mierzejewski <dominik at greysector.net> 
wrote:
> > On Sunday, 13 May 2007 at 00:12, Arjan van de Ven wrote:
> > > Hi,
> > >
> > > some of you already know that I've been working on getting Linux
> > > (and Fedora) to be a lot better about power usage on laptops by
> > > avoiding spurious wakeups and context switches and such (look at the
> > > "wakeup" bug in fedora bugzilla ;).
> > >
> > > As part of my job at Intel I've now released a user friendly tool
> > > that allows everyone that uses it to see what the biggest problems
> > > on their own laptop are... The results internally to Intel have been
> > > really good; several people gained an hour of battery just by using
> > > the tool and getting rid of (or fixing) 'broken' applications.
> > >
> > > PowerTOP can be downloaded from http://www.linuxpowertop.org
> > >
> > >
> > > for completeness I've attached the full announcement text I used in
> > > other places below. I hope that enough people will use it and report
> > > / fix issues in software so that the whole Linux experience on
> > > laptops will be a lot better in a few months..
> >
> > Hey, this is pretty cool.
> >
> > Here's what it says on my amd64 desktop:
> >
> > No detailed statistics available; please enable the CONFIG_TIMER_STATS
> > kernel option
> >
> > Suggestion: Enable the CONFIG_USB_SUSPEND kernel configuration option.
> > This option will automatically disable UHCI USB when not in use, and
> > may save approximately 1 Watt of power.
>
> same here using a core 2 duo t7400 on fc6 x86_64

You need to use a tickless kernel (CONFIG_NO_HZ iirc) and one with 
CONFIG_TIMER_STATS enable for the tool to work.  I think recent rawhide 
kernels fit the bill...

Jesse