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

[Tom London]

On 5/12/07, Arjan van de Ven <arjan at fenrus.demon.nl> 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..
>
>
>
> ----------------------
>
> What's eating the battery life of my laptop? Why isn't it many more
> hours? Which software component causes the most power to be burned?
> These are important questions without a good answer... until now.
>
> The Linux 2.6.21 kernel introduces the so called tickless-idle
> feature. This feature allows the processor to be really idle for long
> periods of time, rather than having to wake up every millisecond for
> the timer tick. Current processors save a lot of power if they are
> idle for long periods, which translates into a longer battery life for
> your laptop, or a lower energy bill for your datacenter. However, a
> Linux system consists of more software than just the kernel, and there
> are many tunables involved. It's not easy to see what is going on, and
> as a result the behavior is sometimes far from optimal, and a lot of
> power is wasted.
>
> Intel is proud to announce the PowerTOP tool
> (http://www.linuxpowertop.org), a program that collects the various
> pieces of information from your system and presents an overview of how
> well your laptop is doing in terms of power savings. In addition,
> PowerTOP will provide an indication of which tunables and software
> components are the biggest offenders in slurping up your battery time.
> PowerTOP will update it's display frequently so that you can directly
> see the impact of any changes you are making.
>
> A typical Linux distribution has many components that wake the
> processor up frequently for no good reason. In our testing with
> PowerTOP, we have seen many cases where with some simple fixes, the
> battery life of typical laptops was increased by one hour or more!
>
> We are providing fixes for several of the issues we identified, and we
> encourage the Linux community to help us in this quest to get the
> maximum battery life out of your (hopefully Intel based) laptops. Try
> the PowerTOP tool, join the mailing list or the IRC channel and
> provide feedback, problem reports or fixes!
>
Interesting.....

Bringing up a gmail tab in firefox appears to push firefox from about
60 to about 500 wakeups per second....

Selecting 'standard without chat' mode brings it back down to about 60.

Anyone know what is going on with google/gmail chat?

tom
-- 
Tom London