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1*9c5db199SXin LiWhat's eating the battery life of my laptop? Why isn't it many more
2*9c5db199SXin Lihours? Which software component causes the most power to be burned?
3*9c5db199SXin LiThese are important questions without a good answer... until now.
4*9c5db199SXin Li
5*9c5db199SXin LiThe Linux 2.6.21 kernel introduces the so called tickless-idle
6*9c5db199SXin Lifeature. This feature allows the processor to be really idle for long
7*9c5db199SXin Liperiods of time, rather than having to wake up every millisecond for
8*9c5db199SXin Lithe timer tick. Current processors save a lot of power if they are
9*9c5db199SXin Liidle for long periods, which translates into a longer battery life for
10*9c5db199SXin Liyour laptop, or a lower energy bill for your datacenter. However, a
11*9c5db199SXin LiLinux system consists of more software than just the kernel, and there
12*9c5db199SXin Liare many tunables involved. It's not easy to see what is going on, and
13*9c5db199SXin Lias a result the behavior is sometimes far from optimal, and a lot of
14*9c5db199SXin Lipower is wasted.
15*9c5db199SXin Li
16*9c5db199SXin LiIntel is proud to announce the PowerTOP tool
17*9c5db199SXin Li(http://www.linuxpowertop.org), a program that collects the various
18*9c5db199SXin Lipieces of information from your system and presents an overview of how
19*9c5db199SXin Liwell your laptop is doing in terms of power savings. In addition,
20*9c5db199SXin LiPowerTOP will provide an indication of which tunables and software
21*9c5db199SXin Licomponents are the biggest offenders in slurping up your battery time.
22*9c5db199SXin LiPowerTOP will update it's display frequently so that you can directly
23*9c5db199SXin Lisee the impact of any changes you are making.
24*9c5db199SXin Li
25*9c5db199SXin LiA typical Linux distribution has many components that wake the
26*9c5db199SXin Liprocessor up frequently for no good reason. In our testing with
27*9c5db199SXin LiPowerTOP, we have seen many cases where with some simple fixes, the
28*9c5db199SXin Libattery life of typical laptops was increased by one hour or more!
29*9c5db199SXin Li
30*9c5db199SXin LiWe are providing fixes for several of the issues we identified, and we
31*9c5db199SXin Liencourage the Linux community to help us in this quest to get the
32*9c5db199SXin Limaximum battery life out of your (hopefully Intel based) laptops. Try
33*9c5db199SXin Lithe PowerTOP tool, join the mailing list or the IRC channel and
34*9c5db199SXin Liprovide feedback, problem reports or fixes!
35*9c5db199SXin Li
36*9c5db199SXin LiWebsite:      http://www.linuxpowertop.org
37*9c5db199SXin LiIRC:          irc.oftc.net    #powertop channel
38*9c5db199SXin LiMailing list: http://www.bughost.org/mailman/listinfo/power
39*9c5db199SXin LiTags: intel, linux
40*9c5db199SXin Li
41*9c5db199SXin Li
42*9c5db199SXin Li
43*9c5db199SXin LiIf you have bugreports or patches, I prefer that you use the mailing list
44*9c5db199SXin Libut you can email me directly at [email protected].
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