Power consumption with Fedora

[Jaroslav Skarvada]

----- Original Message -----
> 
> 
> ----- Original Message -----
> > On Tue, 02 Dec 2014 14:44:59 -0700
> > "Nathanael D. Noblet" <nathanael at gnat.ca> wrote:
> > 
> > > On Tue, 2014-12-02 at 21:47 +0100, Jan Kratochvil wrote:
> > > > On Tue, 02 Dec 2014 06:30:57 +0100, Nathanael d. Noblet wrote:
> > > > > I don't know much about it but I hate how bad my battery life is
> > > > > on my laptop...
> > > > 
> > > > My 3 years old Lenovo X220 lasts for 12 hours (powertop reports so)
> > > > on Fedora 20 x86_64 with powertop --auto-tune.  According to
> > > > powertop approx. 5.5W is display backlight and 1W is the rest of
> > > > system.
> > > > 
> > > > Just to give a reply that Fedora is not bad on all configs/hardware.
> > > 
> > > Well until yesterday I didn't know that Fedora didn't install /
> > > configure any of these packages. I've installed tlp and powertop, I
> > > didn't know powertop did anything other than monitor. I'll see what
> > > powertop --auto-tune does. I don't even know if the tlp package has
> > > enabled anything either. I wonder if having tlp installed and running
> > > powertop --auto-tune will conflict / fight each other...
> > > 
> > > Time to try stuff out.
> > 
> > You might also look at tuned...
> > 
> > (I think it was mentioned early in the thread).
> > 
> > tuned-adm profile powersave
> 
> I've probably said this before, but I wouldn't trust tuned one bit, after I
> was
> told that 1) no measurements were ever taken

Well, it's not easy to objectively measure this, results depends
heavily on HW, SW, configuration used and things like moon phase -
today's HW manage a lot of on its own in FW by utilizing factory
algorithms/optimizations, but attempts were made
to evaluate efficiency of the powersave profile regularly accross
different HW:

http://fedoraproject.org/wiki/Test_Day:2013-11-14_Power_management#Basic_2
http://fedoraproject.org/wiki/Test_Day:2013-04-17_Power_Management#Basic_2
http://fedoraproject.org/wiki/Test_Day:2012-10-11_Power_Management#Test_Results
http://fedoraproject.org/wiki/Test_Day:2012-04-04_Power_Management#Test_Results
https://fedoraproject.org/wiki/Test_Day:2011-09-29_PowerManagement#Test_Results

These numbers are not bad at all.

The powersave profile is targeted for lowest power consumption.
I.e. it throttle down your machine - it sets most of the kernel
knobs to "powersave" policy. This can increase you
online time if your machine is mostly idle, but it will also
increase latency and lowers throughput, so generally balanced
profile is better choice for laptop.

Patches are welcome, so feel free to do your our measurements/
experiments/scientific research or whatever and provide patches.


2) no attempts to make
> beneficial
> configurations the defaults were made (which is probably right, given that
> they'd
> have no data to back it up).
> 

Tuned is tool/framework to ease management of tunings and also provides
dbase of well known tunings. You can use it to e.g. fine tune your system
for high throughput, then roll-back and re-tune for e.g. low latency.
Tunings are also applied to newly added devices. You can use inheritance
when constructing your own profiles for your own workloads/scenarios.
Great for benchmarking, experiments, for cases when "auto" is simply not
good enough and you know what you are doing. Currently the project is receiving
mostly patches for performance tuning, but patches for other profiles are
also welcome. The goal is to be non distro specific upstream. The goal
isn't to press anything to distros defaults

regards

Jaroslav