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!
===
Source: Arjan van de Ven <arjan@linux.intel.com> on LKML
I wrote a small ebuild for PoweTop 1.0 => sys-power/powertop could be the best
category.
I´m not shure if this is the right way or any maintainer will care of the
package: There´s a version bump to 1.1
Changelog:
1.1 --
* Fix bug that shows "you don't have C-states" on mobile CPUs when the cpu is
100% busy as reported by Friedrich
* Cosmetic code cleanups (Lindent) as suggested by David Brownell
* Get rid of popen() and the static sized events array (Keith Packard)
* Add some more tips for kernel config options based on various
reports/feedback
* Improve "you are not root so can't get timerstats" message to say that you
need to be root rather than that you need to change your kernel config
* Make a better effort at locating the kernel .config file
* Don't show "please turn CONFIG_FOO off" if the kernel you have doesn't even
support CONFIG_FOO (yet)
* Show absolute per-second wakeup counts too (multiple requestors)
* Add capability to suggest disabling daemons and the like
1.0 --
* Initial Release
