I got 12% battery drain in 17 hours, standby. I'm not a pro at android but I might give a little tut. on how to save battery life to the max. Atleast, it works for my P500 so it should work for you & for any other android device as well.
Uninstall every unnecessary app, including system apps (those apps, that does not mess up with the system stability - If you uninstall Email app, you will not solve your problems with Gmail app).. same with Messaging. That said, leave as minimum apps in the background as you can. App killer does not solve this problem, it just closes bg apps - they restart after some time. I'm using ATK (Advanced Task Killer), It usually kills 1 - 3 apps, so.. I have a minimum of apps running in the bg.
Basic stuff.. turn off your 3G, wifi, bg sync, gps when not in use. If you need to check your email, use 2G network only option, not 3G. Use 2G always when you don't need 3G speed. Screen brightness is not that important if you set it to anywhere below 70%. It should not drain the battery that fast.
Setcpu - profiles - governors--
My profiles are as follows
Charging - 480min - 748max
Battery <90% - 245min - 600max
Battery <70% - 245min - 600max (U can live with one profile for the battery, I have 2 in case I want to change the 2nd profile)
Screen off - 122min - 245max -- This is what saves my battery in standby.
The governors are ondemand for usage & conservative for screen off.
I'm using Void.echo rom with tapps & gapps modules, uninstalled everything I don't need.
I hope this helps If anyone has a better idea on how to save battery life, please share yours as well.
Thanks for your post, but actually most background apps don't drain battery. I have made lots of experiments (removing system aps, preventing autorun etc., and I don't see any major difference in battery life. So now, I'm on stock 2.2 and I'm now at 80% after almost 30h use: about 20 min talk, 10-15 min wi-fi (mail), 10-15 min EDGE. The latter by the way drains battery more than wi-fi. So instead of messing with system apps I recommend putting the phone in airplane mode during the night and as mentioned in the above post - not using 3G when not needed (EDGE has decent speed).
thats the why linux works !!! use all the memory u possibly can...These Microsoft *****es have changed the way computers were supposed to be used not reinstalling windows and other crapware all the time..Switch to Debian while its still time
And i use these settings
screen off 245-245 powersave (otherwise phone gets hot Its summer in india)
600-245 ondemand otherwise
kopchev said:
Thanks for your post, but actually most background apps don't drain battery. I have made lots of experiments (removing system aps, preventing autorun etc., and I don't see any major difference in battery life. So now, I'm on stock 2.2 and I'm now at 80% after almost 30h use: about 20 min talk, 10-15 min wi-fi (mail), 10-15 min EDGE. The latter by the way drains battery more than wi-fi. So instead of messing with system apps I recommend putting the phone in airplane mode during the night and as mentioned in the above post - not using 3G when not needed (EDGE has decent speed).
Click to expand...
Click to collapse
If there are many apps running in the bg, phone runs out of ram, so it tries to free up some space constantly. I think that drains battery, not the apps themselves. As well as the more cpu power is used, the faster it drains battery. Airplane mode shuts off any connection, so either that or you could just shut down the phone during night. Hmm you could tell me how to prevent app autorun, i have not looked into that.
btw juicedefender does wonders with the phones battery i had a 2% percent over night normal mode (not airplane) no 3g/Edge/Wifi/Bluetooth active and just sleeping
sarfaraz1989 said:
thats the why linux works !!! use all the memory u possibly can...These Microsoft *****es have changed the way computers were supposed to be used not reinstalling windows and other crapware all the time..Switch to Debian while its still time
And i use these settings
screen off 245-245 powersave (otherwise phone gets hot Its summer in india)
600-245 ondemand otherwise
Click to expand...
Click to collapse
True about windows & linux hehe. You havent tried 122-245mhz on screen off? Ofcouse, it lags even when i receive an sms, it's something like this - the screen turns on, then after 2 sec. i hear a notification, then after 1 sec. i see the sms but that does not make any problems for me, it's extreme powersaving
I don't get the point of airplane mode while you're sleeping.
If you don't want to get calls while sleeping, shouldn't it be better if you turn off the phone?
I had a good experience with JuiceDefender until now too. Last night my phone was 100% and no airplane mode while sleeping. It drained only 3%.
SoundTone said:
If there are many apps running in the bg, phone runs out of ram, so it tries to free up some space constantly.
Click to expand...
Click to collapse
From what I've read, Android doesn't swap. It'll just kill the background apps on it's own. I don't think there even is a swap unless you root, rom and create one on your uSD.
rapharias said:
I don't get the point of airplane mode while you're sleeping.
If you don't want to get calls while sleeping, shouldn't it be better if you turn off the phone?
I had a good experience with JuiceDefender until now too. Last night my phone was 100% and no airplane mode while sleeping. It drained only 3%.
Click to expand...
Click to collapse
It's more convenient, because the on/off process is quite slow...in contrast - airplane mode on/off is 3-4 secs. In airplane mode you can still use wi-fi. Last night the battery drained only 1%
i read somewhere that changing the CPU speed doesnt change the voltage, thus it does not affect battery life... anyone can confirm this???
As far as I can remember from school, a logic gate uses more power when switching, thus a higher frequency would also mean higher power drain (higher frequency = more switching of the logic gates), without voltage modification.
Voltage is changed in order to keep stability - higher voltage means a more stable logic signal, and a faster switching gate, and thus people reccomend using a higher voltage for higher frequencies/lower voltage for lower frequencies.
Thus, a CPU with so many logic gates does not operate just like a simple resistor. In fact it is worse, because when you use higher voltage AND higher frequency power drain is increased much more.
On the other hand, most modern CPU's simply deactivate CPU regions when idling, so, in case of our hardware (constant voltage) there should not be such a great difference when idling (most of the CPU is powered down). The only thing is for the phone to be REALLY idling (no background tasks eating too much of the CPU when screen off).
Basically, what this means is that if you want extreme power saving use a governor with 128MHz minimum and have as few background services as possible (or at least the ones that are there should be optimized for the least CPU usage).
Now I use the standard governor (248 - 600) and I thing my idle power drain is OK.
I guess I will test a governor that is plain 600MHz and one wit 320 or 480 as a minimum, in order to see if power drain is higher when using a lower lag configuration.
And, just as a guess, if background tasks are triggered by timers, a governor with just 600MHz (or 320 - 600 or 380 - 600?) could (just a wild guess) mean that background tasks take less time to execute, and leave the CPU to si more in IDLE mode, causing a very similar power drain as an extreme power saving governor. But this is just a guess, i have not tested it yet. And it also depends on what apps you have (what the apps do when phone is sleeping).
Basically, my best advice would be to watch the apps (after you install a new app, wait for a night to see if the new app causes a higher drain; if it does, search for another app that does the same thing)
spaic said:
As far as I can remember from school, a logic gate uses more power when switching, thus a higher frequency would also mean higher power drain (higher frequency = more switching of the logic gates), without voltage modification.
Voltage is changed in order to keep stability - higher voltage means a more stable logic signal, and a faster switching gate, and thus people reccomend using a higher voltage for higher frequencies/lower voltage for lower frequencies.
Thus, a CPU with so many logic gates does not operate just like a simple resistor. In fact it is worse, because when you use higher voltage AND higher frequency power drain is increased much more.
On the other hand, most modern CPU's simply deactivate CPU regions when idling, so, in case of our hardware (constant voltage) there should not be such a great difference when idling (most of the CPU is powered down). The only thing is for the phone to be REALLY idling (no background tasks eating too much of the CPU when screen off).
Basically, what this means is that if you want extreme power saving use a governor with 128MHz minimum and have as few background services as possible (or at least the ones that are there should be optimized for the least CPU usage).
Now I use the standard governor (248 - 600) and I thing my idle power drain is OK.
I guess I will test a governor that is plain 600MHz and one wit 320 or 480 as a minimum, in order to see if power drain is higher when using a lower lag configuration.
And, just as a guess, if background tasks are triggered by timers, a governor with just 600MHz (or 320 - 600 or 380 - 600?) could (just a wild guess) mean that background tasks take less time to execute, and leave the CPU to si more in IDLE mode, causing a very similar power drain as an extreme power saving governor. But this is just a guess, i have not tested it yet. And it also depends on what apps you have (what the apps do when phone is sleeping).
Basically, my best advice would be to watch the apps (after you install a new app, wait for a night to see if the new app causes a higher drain; if it does, search for another app that does the same thing)
Click to expand...
Click to collapse
I don't know about CPU's as much as u, but simple logical thinking helps here.. Low frequency + minimum of bg tasks = great power saving, I have now used the phone for 36hours without charge, 61% battery left. That is not only idling, i write about 50 to 150 sms a day & use the phone for other stuff too. So, those governors & frequencies i mentioned earlier in this post, helps a lot.
fransisco.franco thinks otherwise read the his post that contains the link to his rom devoid.francov6(ROM is cool btw and unfortunately i have a slow sdcard )
I think the first post is by far the best I have seen so far.
Sent from my LG-P500 using Tapatalk
Wow, only 1% all night?
I'll take a deeper look at your tips!
I use devoid.franco with franco.kernel v12. From all ROMs I've isntalled, it's the best: great performance and long battery life.
I get 5% battery drain in 7:30 hours (at night), without doing anything special, without running a custom ROM and without uninstalling apps. I just make sure GPS, Bluetooth, WiFi and data are off before going to bed.
I've install Rom Toolbox,
and i saw there is a "CPU slider" where i control the clock speed.
i've put it to 1000MHz instead of 1200MHz and tested it for several days
i really dont feel any difference in performance.
browsing seems same, games like asphalt is equally smooth.
heating is similar, equally warm.
the only difference is quadrant benchmark.
1200MHz scores 3200-3400
1000MHz scores 2600-2900
frankly speaking, i'm not sure if there's any difference in battery life.
is there any way to accurately test whether the clock speed affects the battery life?
i've seen other threads, where there are very different opinions.
some say it will improve battery life, and some say its worst.
http://forum.xda-developers.com/showthread.php?t=726019
Quote: (SetCPU doesn't make a difference in battery life, it can only shorten it. The kernal already has the best settings for CPU speed built in.)
http://forum.xda-developers.com/showthread.php?t=1305465
Quote: (if you are able to stand the side effects of underclocking, it will surely boost your batery life.)
On my SGS2 program called CpuSpy shows that 1200MHz is about 1% of total cpu time (remember that governor is ondemand and CPU is at 1200 only when need it). If power consumption is directly proportional to clock speed by limiting it to 1000MHz you will get about 20% less power usage by 1% of time... looks like 0.2% power saved ? Soo if Your phone works for about 48h on one charging this way You can get about 6 extra minutes. It's just my guess...
Also have to consider if slower cpu causes screen to eat power for longer time... (because You have to wait longer for operation to complete)
slig said:
On my SGS2 program called CpuSpy shows that 1200MHz is about 1% of total cpu time (remember that governor is ondemand and CPU is at 1200 only when need it).
If power consumption is directly proportional to clock speed by limiting it to 1000MHz you will get about 20% less power usage by 1% of time... looks like 0.2% power saved ? Soo if Your phone works for about 48h on one charging this way You can get about 6 extra minutes. It's just my guess...
Also have to consider if slower cpu causes screen to eat power for longer time... (because You have to wait longer for operation to complete)
Click to expand...
Click to collapse
HI, thanks for replying. I understand what you mean. the phone dont operate at 1200MHz all the time. but when using browser, and playing games, such as asphalt, it runs at max CPU usage almost the entire gaming duration.
Anyway.....
the real question is whether the clock speed is directly proportional to the battery consumption.
while reading your post, i thought of a brilliant ideal how to verify this.
the CPU slider not only allows you to set the max CPU speed,
you can set the min CPU speed as well.
So, i thought of an experiment, lets set the min & max CPU to 1200MHz,
this way, the phone will be running constantly at max CPU even when its idle.
let the phone be turn on till it run out of battery, record the time, T1.
then repeat again with max and min CPU set to 1000MHz.
record the time it is turn on till it run out of battery, record time as T2,
then compare T1 & T2, this could certainly work.
it would be nice if any member here happens to have 2 sgs2, and tried them ;-)
There are two more things to consider
1. CPU is not the only element that consumes power.
2. SGS2's Exynos is always clocked at 200MHz when the screen is off - check if this minimum slider affects that too.
Please let know how your experiment goes.
Regards
when the screen is off, the phone will be in "deep sleep" state. i think thats less than 200MHz.
anyway, i wont be doin this experiment any time soon.
you see, this is my only phone, i need to use it.
i dont have much oportunity to leave it and wait for it to run out of juice.
still, i'll try it when i have the chance.
First of all, we are talking about Stock ROM governors. Of course we could discuss other kernels here, but keep in mind that this, mainly, a comparison of Performance vs Ondemand governor for battery savings.
Someday i've read here in those threads of Governor Descriptions a theory that Performance Governor could save Battery against OnDemand and even others governors, because he does not waste energy and time trying to scale, since it scales to full clock, and with that it could finish its tasks quickier than others, allowing it to return faster to iddle.
So, after reading that, i felt tempted to ride this horse
I've installed setCPU and created a profile in the first one for Screen Turn Off, setting a low max frequency (around 500mhz), and with the help CPU Sleeper (Turn of one of the cores when screen is shut down), i could maximize this economy. I guess the only demanding processes my Xperia S could run when Screen Off are, of course, music playing apps.
Result: A smooooooth UI and it seems the battery comsumption is a bit better (maybe more than a bit) than OnDemand. I don't have concrete numbers, but with the help of GSam Monitor and a Use with some moments of Intense WhatsApp, some mild WhatsApp, a bit of UI browsing, App Uninstalling and about 20% brightness i calculate that i would have a Battery Life of about 20 hours!
My next step is to start to set a different Maximum Clock per App (setCPU 3.0 allow me to change governor and clock based on active app), lowing it enough so that i have a smooth app operation and battery economy.
What do you think guys?
Hey guys,
I did an experiment not a long time ago. I have my old phone with 4.1.2 Android and I went on a trip for a few days. Typically my phone discharges after 12-15 hours even without using anything (old battery) with smartassv2 or just conservative mode. Before going on the trip, I've set the minimum clock to the lowest possible and set the mode to powersaving (always using the minimum). And after 3 days the battery still was at 86%.
So what's the problem with the Android OS itself? Or have I just gotten some magical experience? Why does it use such a large clock rate for the processor when it's locked and using any preference script apart from power saver?
Thanks a bunch!
First of all, battery life depends on your battery type and capacity.
Second of all, when you underclock your cpu to the minimum frequency, battery consumption will decrease a LOT but using this frequency for apps use is practically impossible.Also, display causes less battery life.
Hope i helped !
Forgot about this topic. Yes, mate, I understand that, but the minimum frequency is enough when I don't have any apps running in the background. Seems like android still has a lot of power managment programming to be done under standby.
Maybe I wasn't clear enough, but if you just use any governor (with minimal frequency set at the lowest) apart from "powersaving", it will use more power on standby, then powersaving with the minimal frequency set.
For few days I will not have access charging my battery. I am thinking about disabling cores and lowering maximum cpu frequency for better battery life. I have root and carbon rom. Is it efficient disabling cores and make one core at %100, or 4 cores at lower use percentage? And what are my other options to save battery? I don't care much performance. I don't mind slowing down. I wish I could test myself but I don't have time to test.
Daily I use 3 cores at 1036MHz without excessive lags. I'm using SetCPU to do it. It's possible to create profiles and set frequency, governor and scheduler when a specific app is launched, when battery reaches into a low level, when screen is On/Off, etc.
Screen time about 7,5 hours.
For gaming I need to change it, of course.
I'm using Abricot kernel.