Thread: [ANNOUNCE] Speed Patch + Battery Patch + Tweaks --> Everything Needed To Have A Perfect N900
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vi_ is offline vi_
2011-12-09 , 14:05
Posts: 1,680 | Thanked: 3,685 times | Joined on Jan 2011
#2801
Originally Posted by carbonjha View Post
@karam
I found some linux governor tweaking tips in this website. http://www.ibm.com/developerworks/li...req-3/?ca=drs-

Its a very long and detail guide with lots of comparing graphs. I couldn't read the full guide. But it concludes with tweaking the conservative governor's up & down threshold which seems to have a significant effect on battery saving.

"overclock" profile of batterypatch uses conservative governor. I wasn't using it for a while because I changed it to ondemand. But today I thought about giving it a try. Then I find that first time the conservative governor loads with its default parameters ignoring the "overclock" profile & always remains that way.
Code:
up_threshold = 80
down_threshold = 20
freq_step = 5
ignore_nice_load = 0
sampling_down_factor = 1 
sampling_rate = 3000000
sampling_rate_max = 1500000000
sampling_min = 1500000
now Im testing these tweaks
Code:
echo 98 > /sys/devices/system/cpu/cpu0/cpufreq/conservative/up_threshold

echo 95 > /sys/devices/system/cpu/cpu0/cpufreq/conservative/down_threshold


echo 1 > /sys/devices/system/cpu/cpu0/cpufreq/conservative/ignore_nice_load
underclock profile uses ondemand governor and it loads ok. so no need to change that. Lets hope it works well.
Christ on friday. These are the worst settings I have ever seen for a cpufreq govenor, let alone conservative.

With these idiotic settings your CPU will be switching frequency EVERY TIME IT SAMPLES unless your CPU is sitting inbetween 95 to 98% useage. If you want an erratic, power hungry lag machine then by all means use these settings.

The best governor is ondemand. Rationale? When the device does nothing you want it to be using no power i.e. cpu asleep. When the machine is doing constant light work i.e. playing mp3s you want it to be in a low frequency. When the machine is doing hard work you want it to be running fast,

You need ondemand, low=250, high=805, up threshold 93.

Low 250 so on normal wake ups and mp3 playing it will spend 85% of the time in 250, 15% at 500. This gives long battery life under light useage/idle.

Max 805, power increases with the square of the voltage used. Voltage use rises significantly from about 750 and up. 805 seems a good compromise.

I cannot be bothered ripping into conservative, take my word. It is rubbish.


If you want to save battery power you need to disable all the badly coded, cpu hungry crap you may have installed. Call notify for example is a total CPU rape potato.
__________________
N900: One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die.
 

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