[Tips & Tricks & Discussion] Battery Calibration/Improving Battery life

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aukhan

Senior Member
Feb 19, 2013
4,700
4,015
Bangalore
ajqi.com
Battery Calibration/Improving Battery life

Requirements:
Device needs to be rooted "Obviously".
Need to have Rom Tool Box Lite or Rom Tool Box Pro.
Some Basic Knowledge on how to use the app.


Note: Turn off Wi-Fi, Bluetooth, GPS, and Auto-sync if they are not in use. Hold down the notifications bar to disable them and activate the Power Saving mode which will make the device conserve energy under low battery state.

Battery Calibration Procedure.
1. Use your phone until the phone battery drains out completely and device gets switched off
2. Switch on the Device to make sure battery really is 0%.
3. Now plug in charger (Device turned off, Dont turn on the device)& leave it for charging until it reaches 100%
4. When the battery is full, switch on the phone, unplug the charger & check if the battery drops by 1 or 2% immediately.
5. If you notice battery drops immediately plug in charger once more (while the phone is on) & let it charge completely.
6. Once charging to 100% is done, don't disconnect the charger, open your root explorer, Provice RW permissions.
7.Search for 'DATA' Folder then 'SYSTEM' Folder.
8.In the 'System' folder you will find 'batterystats.bin' delete this file.
9.Exit Root Explorer and Use your phone normally unless it completly drains the battery(Dont connect your charger)
10.Power On your device and charge your device untill it reached 100%
11.Now you should enjoy the Samsung long Battery Life!!

Note: These methods are not permanent this worked for me so sharing with you.

Greenify your Apps:

NEW: Non-root working mode is now supported in 2.0+, Greenify is a convenient utility that will consequently hibernate battery hoarding applications that wait out of sight after you're done utilizing them.
Google Playstore & Thread

Titanium Backup:
Great battery life, wonderful execution and cool customization— we have seen one or more applications for these things. Presently we should see an alternate must have and a standout amongst the most evaluated applications for established Android gadgets. On the off chance that you got root benefits on your gadget, Titanium Backup is an exceptionally suggested application for you. You may discover various reinforcement applications at the Google Play Store, however none of them does the employment so splendidly and pleasantly.
Google playstore
 
Last edited:

aukhan

Senior Member
Feb 19, 2013
4,700
4,015
Bangalore
ajqi.com
The KERNEL can do some important things to help with battery saving as it is the controller of all things working in your phone:

1. Underclocking - if you feel your phone is fast enough, go ahead and lower the maximum frequency of your CPU, it will save power as the faster the CPU goes, the more energy it uses.

2. Undervolting - it's more complicated; every CPU requires certain amount of supplied voltage to run and the amount increases with the speed of CPU (clock frequency). For example 200Mhz requires only 0.9V while 1600Mhz requires 1.25V by default. The thing is, the higher the voltage, the higher the heat and of course power consumption. So the best way to lower it is to lower voltage - Samsung had to set voltage at the high enough level that every CPU they produce would work correctly but every CPU is different and some of them allow for lowering voltage and still remaining fully stable thus using less power to do the same work. Typically you can save about 0.05V but some CPU will allow as much as 0.1V to be saved. The same really goes for our GPU part, it can be undervolted as well. There are other parts in our phone that can be undervolted, like memory or controllers of various part but I have found (well in my phone) that saving were very small and caused instability so I would not recommend playing with them. We could think about undervolting our display as it is the biggest consumer of energy in our phone but actually we are doing it all the time The voltage supplied to the screen decides its brightness so if we were to lower the voltage it would just get dimmer
3. There are small savings to be had in various other parts controlled by the kernel:
- first and second thing are tied with SDcard - using it carries high power requirements - the less we use it, the better. Now we can't reduce to completely as all our data, apps and whole system is on it but we can reduce it's use by setting various caches.
a) read cache for internal and external SD combined with scheduler that minimizes reads and writes - so far the best scheduler created specifically for mobile SD use is FIOPS, so using that with a large buffer (maximum of 4096) is actually the best from energy standpoint.
b) system swap space - some kernels allow for creating a very specific kind of swap space, Android will use it once the free memory falls below certain point. Normally this swap space would be placed on SDcard but in this case it's inside a specific region of RAM. Why it is created like this? Because it can be easily compressed to keep more data, so basically we are using Android mechanisms and compressing memory so we can run more apps and keep them in physical RAM That means they are accessible faster than if we were to read them from SDcard and they use less power. Compressing and decompressing data as they go in and out of swap space is still far less energy consuming process then reading them from SDcard.
- third is governor configuration - governor is a system service that decides at what frequency should the CPU be working at every moment and how much cores should be enabled - this of course has great impact on energy consumption and on the smoothness of our experience with our phone. There are two schools of setting up governor and they base their decisions on two premises:
a) sharply increase CPU speed to get the work done fast and sharply decrease speed once it's not needed.
b) slowly increase speed and only so much to do what must be don then slowly decrease speed once you are done because you may have to do something again in a moment
There are pros and cons of both ways - way A means jumping to high frequency for a short time but high frequency uses comparatively large amount of energy, way B means slow increase but also means remaining in intermediate states for longer actually using energy for longer. I don't have any way to actually measure the resulting energy consumption but way A has a distinct advantage of creating much smoother experience so I use that myself.
- fourth is hotplug configuration - our CPU can dynamically enable and disable additional cores - the process is called hotplugging. Some governors are created specifically for controlling this process, the best, as far as I have tested, in this is Lulzactiveq. Hotplugging has to be wise as to the IF and WHEN to enable and disable additional cores, it measures how many "packets" of data are in queue to be processed and based on short history anticipates increase and decrease of workload.

All those interesting options are configured in scripts created for main contemporary kernels: Nadia, Devil and Agni and available HERE.

Latest OC / UV Scripts for Devil / Agni and Nadia Kernels for Note 2 are HERE
Guide to EXT4 to F2FS migration for Note 2 is HERE

Courtesy:mad:Mat9V
 
Last edited:

yogi909

New member
Jun 12, 2014
2
2
Very briefly stated.

Thanks for sharing

I read all your posts, This will help me in my next configuration for Emotion V7, Nadia with mat's script.

Now on Emotion V6 ....AGNi Pure Stock v4.2.2
 
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KNIGHT97

Senior Member
Jan 30, 2014
2,111
1,635
Mumbai
The android system, unlike other OS's actually displays the battery reading from a written data config, known as battery stats in general. While there is, in perception no disadvantage to this method of reporting the average remaining battery life, it isn't the actual battery life you are getting, but the percentage read from your daily usage and then sends the information to the OS for displaying the battery life. Due to this, you can have the percentage misreported, so it is suggested to factory reset every 6 months on stock unrooted and if rooted wipe battery stats using rom toolbox free/pro every 2 weeks to ensure correct reporting of your battery life.
Note - This won't increase battery life, but will ensure correct reporting of battery percentage, which gets messed up quite quickly on custom roms(for some unknow reason).

Undervolting can cause battery drain or better battery life depending on your configurations, if you have the CPU set to running high many of the times(like from a governor or background apps that need regular wakelocks for syncing content) it will slow down the ramping up of frequencies during deep sleep(no effect when screen on) and thus it will hold a longer wakelock for the purpose, so undervolt carefully depending on your usage - mild to mid(medium to high undervolt), mid to high(low to medium undervolt), heavy(low to no undervolt).

Different governors have different scaling methods for CPU, thus will give better or worse battery life depending on your config and usage. A governor ramping up faster and scaling down slower will give better battery life in scenario of heavy usage because the device can go to deep sleep state faster and perform background syncs in an instant; while someone with low to mid(or a bit high also) would like to have a governor that ramps up slower and scales down slowly too so as to complete the syncing of files and media scan(if running) and make the device perform smoother and go into deep-sleep and remain in the state for longer times(though going to DS mode will be a bit slower than a fast downscaling governor) and will occasionally wake up for background syncs, but those will be longer, but won't have much effect on battery life because of lower frequencies being used and syncing complete before high frequency threshold is reached.

Depending on what a user needs for his daily usage it is a good idea to keep the rest of apps(preferably facebook, musixmatch, instagram and shazam) hibernated using something like greenify(which now supports auto-hibernation without root in the beta versions). Auto sync should only be enabled for apps that need it, like E-Mail, Google+, Gmail etc.and rest should be set onto manual sync.

Samsung has a habit of throwing in a lot of features onto their device, so keeping motions enabled, which you don't even use, except for a show-off, is a bad idea because it will drain battery. Exploring the settings menu to disable unneeded things can pay-off as a positive fruit for patience.

Keeping the storage clean is also a good way. A corrupted or highly filled up storage requires more passes to be read and thus keeps the media scanner process running for longer, which puts a strain on the battery life. Also, android OS is based of the 32-bit kernel of linux(for now, 64-bit is planned to be introduced after some time), so the media scanner has to look for data linearly in the storage blocks on the internal and external SD, unlike 64-bit where the data is arranged into random blocks which are then brought together as one and the media scanner can be informed of the address of the blocks due to more threads allowed to be run for same process and also a higher memory bandwidth allocated to each process so as to make it perform faster. Due to this reason, the media scanned isn't informed of all the addresses on the time of data writing and thus has to scan linearly looking for bits of data. So keep the storage clean and minimal. Cloud is a good way if you have decent internet and won't need access to the files stored there in regular period of times.

If using a custom rom make sure that it either comes with the modem for your region or flash the modem of your region after that, so as to ensure better signal stability and thus better lasting battery life. A correct modem can give more dBm of signal at the same place as compared to a wrong one.

A good way to have stable battery life is to enable power saving mode in areas with low signal and when on low battery life only, keep it disabled otherwise or it will slow down the race-to-idle for Deep sleep mode and hence cause a bit more battery drain just before deep-sleep state.

Having location services enabled all the time isn't a good idea either, use it only when needed and keep GPS off otherwise. Samsung allows toggling of most things from notification panel so use it.

Smart stay, smart pause, smart scroll all use the front camera for detection, which requires high voltage for operation(separate from CPU, uncontrollable by software) so keep them off unless needed.

Make sure to keep your device clean. How does this affect battery life? Dust and other things when collected around pins, sockets and connectors prevent efficient passing of electricity and thus forces the device to demand more energy, around half of which is taken away by these. Even metallic dust can have adverse effect due to it making the transfer more rapid and forcing the battery to supply the power, which is most probably wasted.

Automatic brightness is good during daytime, but useless during late evening and night, because brightness level doesn't need to be changed and it keeps the light sensor activated. Disable it after 7 Pm(you can also set up tasker or some other automation tool for this).

An Odexed rom provides more battery life as compared to deodexed, but at the cost of available customization as no mods will work and will instead crash the file related to them. Choose your side wisely and patiently.

If you're going to use some app, check if it uses GCM for providing notifications(usually google search at your service), if not look for an alternative which does. GCM doesn't even use marginal amount of battery and is more efficient in providing the notifications at time and also doesn't need a persistent notification.

Check for wakelocks thoroughly and remove the misbehaving apps or hibernate them if you need them on your device. Also, be sure to update the apps for receiving any fixes and optimizations, which can sometimes also decrease the required wakelock frequency for an app and thus preserve battery life.

Don't keep too much of auto updating widgets on homescreen, these only serve to drain the battery further by auto syncing.

if rooted, use Xposed and boot-manager to disable unneeded apps at boot time and thus preserve battery and time required for full boot-up.

If on a custom kernel use DAC direct(if available) for sounds. This bypasses the output mixer and thus preserves a little bit of battery required to produce and refine the sounds, instead utilize 128x oversampling and FLL tuning for an even better quality.

Don't reboot on a regular basis unless needed, this will eat up battery life quicker.

Don't use any task killer( a long debate on uselessness of those can be found on many sites, with a simple google search), the Android system's LMK is itself more than enough.

Be sure to research carefully on what you really need and what you don't and then use it. Don't go on downloading useless things which you'll delete later on because it creates a small entry in /data/data which gets scanned by media scanner due to being present in its path and thus will make the process longer and more battery hungry.

Some custom kernels allow for controlling deep sleep type. Usually these types are already defined in the kernel tweaking app itself. A person with heavy usage should use the IDLE deep sleep more so the device is able to wake up quickly and doesn't drain much battery in case of many wakelocks. Similarly a light user will benefit with AFTR+LPA due to CPU deep sleep, but this isn't advised for medium to heavy usage(use IDLE+LPA instead) because the wakelocks require a high power to even wake up the device, which will drain more battery if you use your mobile more, because many apps will try to acquire a partial/complete wakelock.

I know this is quite long, but read through carefully and you'll surely get better battery life.


Source : Experience and Google groups
 
Last edited:

yogi909

New member
Jun 12, 2014
2
2
I cannot study myself all technically like you what you mentioned in "[Experience][Share]My Usage and Testing of Custom kernels for Touchwiz Kitkat".
But above is well informative and now i get why i was getting worse battery life & longer wakelock by OC and UV with selective governer.
By testing different setting in AgniPureStock 4.2.2 today i reach 25 hr + battery life with my moderate usage.
I am sure above valued information, i will get most out of my battery.

Thank you very much KNIGHT97 for sharing.
 
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KNIGHT97

Senior Member
Jan 30, 2014
2,111
1,635
Mumbai
if i use greenify i need to install xposed framework too?
Xposed is optional. It is only for the experimental features. However, the developer has got 1 or 2 of those working without Xposed in the latest beta(you'll need to join the greenify G+ community for getting the beta, though)

Sent from my RPG with auto targeting
 

devrog17

Member
May 17, 2014
27
8
nagpur
thanks for the info man.....its very helpful

The KERNEL can do some important things to help with battery saving as it is the controller of all things working in your phone:

1. Underclocking - if you feel your phone is fast enough, go ahead and lower the maximum frequency of your CPU, it will save power as the faster the CPU goes, the more energy it uses.

2. Undervolting - it's more complicated; every CPU requires certain amount of supplied voltage to run and the amount increases with the speed of CPU (clock frequency). For example 200Mhz requires only 0.9V while 1600Mhz requires 1.25V by default. The thing is, the higher the voltage, the higher the heat and of course power consumption. So the best way to lower it is to lower voltage - Samsung had to set voltage at the high enough level that every CPU they produce would work correctly but every CPU is different and some of them allow for lowering voltage and still remaining fully stable thus using less power to do the same work. Typically you can save about 0.05V but some CPU will allow as much as 0.1V to be saved. The same really goes for our GPU part, it can be undervolted as well. There are other parts in our phone that can be undervolted, like memory or controllers of various part but I have found (well in my phone) that saving were very small and caused instability so I would not recommend playing with them. We could think about undervolting our display as it is the biggest consumer of energy in our phone but actually we are doing it all the time The voltage supplied to the screen decides its brightness so if we were to lower the voltage it would just get dimmer
3. There are small savings to be had in various other parts controlled by the kernel:
- first and second thing are tied with SDcard - using it carries high power requirements - the less we use it, the better. Now we can't reduce to completely as all our data, apps and whole system is on it but we can reduce it's use by setting various caches.
a) read cache for internal and external SD combined with scheduler that minimizes reads and writes - so far the best scheduler created specifically for mobile SD use is FIOPS, so using that with a large buffer (maximum of 4096) is actually the best from energy standpoint.
b) system swap space - some kernels allow for creating a very specific kind of swap space, Android will use it once the free memory falls below certain point. Normally this swap space would be placed on SDcard but in this case it's inside a specific region of RAM. Why it is created like this? Because it can be easily compressed to keep more data, so basically we are using Android mechanisms and compressing memory so we can run more apps and keep them in physical RAM That means they are accessible faster than if we were to read them from SDcard and they use less power. Compressing and decompressing data as they go in and out of swap space is still far less energy consuming process then reading them from SDcard.
- third is governor configuration - governor is a system service that decides at what frequency should the CPU be working at every moment and how much cores should be enabled - this of course has great impact on energy consumption and on the smoothness of our experience with our phone. There are two schools of setting up governor and they base their decisions on two premises:
a) sharply increase CPU speed to get the work done fast and sharply decrease speed once it's not needed.
b) slowly increase speed and only so much to do what must be don then slowly decrease speed once you are done because you may have to do something again in a moment
There are pros and cons of both ways - way A means jumping to high frequency for a short time but high frequency uses comparatively large amount of energy, way B means slow increase but also means remaining in intermediate states for longer actually using energy for longer. I don't have any way to actually measure the resulting energy consumption but way A has a distinct advantage of creating much smoother experience so I use that myself.
- fourth is hotplug configuration - our CPU can dynamically enable and disable additional cores - the process is called hotplugging. Some governors are created specifically for controlling this process, the best, as far as I have tested, in this is Lulzactiveq. Hotplugging has to be wise as to the IF and WHEN to enable and disable additional cores, it measures how many "packets" of data are in queue to be processed and based on short history anticipates increase and decrease of workload.

All those interesting options are configured in scripts created for main contemporary kernels: Nadia, Devil and Agni and available HERE.

Latest OC / UV Scripts for Devil / Agni and Nadia Kernels for Note 2 are HERE
Guide to EXT4 to F2FS migration for Note 2 is HERE

Courtesy:mad:Mat9V
Thanks man....you rock:good::good:
 

jUDASFERRET

Member
Jan 8, 2011
8
0
What about using Juice Defender (available in play store)? I used the basic one first and then ended up buying ultimate because I saw good results. Now the location (using cell tower) based WiFi enable/disable extends my battery life significantly.

The is one of the first apps I install once I feel a new flash is stable.
 

Ozpeter

Member
Jun 9, 2014
29
7
If you have the Samsung "Toolbox" utility, that floats a button on the screen to access your choice of five apps from anywhere - turn it off. It causes the "security storage" process to peg at 20% all the time the screen is on if "Toolbox" is enabled. When "Toolbox" is disabled, "security storage" process drops to a couple of percent when the device is idle. There's quite a saving on battery drain.
 
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JW01

New member
Feb 13, 2018
3
0
Battery calibration

I have a rooted Nook HD+ running Android 7.1 and I decided to calibrate its battery.
I ran it down to zero as recommended then attached it to the mains.
All I have had for several hours is a black screen with just the charging symbol (battery with lightning inside it). Nothing else, no progress bar, no charge %, nothing Androidy.
Is this as it should be and should I just wait for several more hours or is there something wrong?
Many thanks.
 

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  • 13
    The android system, unlike other OS's actually displays the battery reading from a written data config, known as battery stats in general. While there is, in perception no disadvantage to this method of reporting the average remaining battery life, it isn't the actual battery life you are getting, but the percentage read from your daily usage and then sends the information to the OS for displaying the battery life. Due to this, you can have the percentage misreported, so it is suggested to factory reset every 6 months on stock unrooted and if rooted wipe battery stats using rom toolbox free/pro every 2 weeks to ensure correct reporting of your battery life.
    Note - This won't increase battery life, but will ensure correct reporting of battery percentage, which gets messed up quite quickly on custom roms(for some unknow reason).

    Undervolting can cause battery drain or better battery life depending on your configurations, if you have the CPU set to running high many of the times(like from a governor or background apps that need regular wakelocks for syncing content) it will slow down the ramping up of frequencies during deep sleep(no effect when screen on) and thus it will hold a longer wakelock for the purpose, so undervolt carefully depending on your usage - mild to mid(medium to high undervolt), mid to high(low to medium undervolt), heavy(low to no undervolt).

    Different governors have different scaling methods for CPU, thus will give better or worse battery life depending on your config and usage. A governor ramping up faster and scaling down slower will give better battery life in scenario of heavy usage because the device can go to deep sleep state faster and perform background syncs in an instant; while someone with low to mid(or a bit high also) would like to have a governor that ramps up slower and scales down slowly too so as to complete the syncing of files and media scan(if running) and make the device perform smoother and go into deep-sleep and remain in the state for longer times(though going to DS mode will be a bit slower than a fast downscaling governor) and will occasionally wake up for background syncs, but those will be longer, but won't have much effect on battery life because of lower frequencies being used and syncing complete before high frequency threshold is reached.

    Depending on what a user needs for his daily usage it is a good idea to keep the rest of apps(preferably facebook, musixmatch, instagram and shazam) hibernated using something like greenify(which now supports auto-hibernation without root in the beta versions). Auto sync should only be enabled for apps that need it, like E-Mail, Google+, Gmail etc.and rest should be set onto manual sync.

    Samsung has a habit of throwing in a lot of features onto their device, so keeping motions enabled, which you don't even use, except for a show-off, is a bad idea because it will drain battery. Exploring the settings menu to disable unneeded things can pay-off as a positive fruit for patience.

    Keeping the storage clean is also a good way. A corrupted or highly filled up storage requires more passes to be read and thus keeps the media scanner process running for longer, which puts a strain on the battery life. Also, android OS is based of the 32-bit kernel of linux(for now, 64-bit is planned to be introduced after some time), so the media scanner has to look for data linearly in the storage blocks on the internal and external SD, unlike 64-bit where the data is arranged into random blocks which are then brought together as one and the media scanner can be informed of the address of the blocks due to more threads allowed to be run for same process and also a higher memory bandwidth allocated to each process so as to make it perform faster. Due to this reason, the media scanned isn't informed of all the addresses on the time of data writing and thus has to scan linearly looking for bits of data. So keep the storage clean and minimal. Cloud is a good way if you have decent internet and won't need access to the files stored there in regular period of times.

    If using a custom rom make sure that it either comes with the modem for your region or flash the modem of your region after that, so as to ensure better signal stability and thus better lasting battery life. A correct modem can give more dBm of signal at the same place as compared to a wrong one.

    A good way to have stable battery life is to enable power saving mode in areas with low signal and when on low battery life only, keep it disabled otherwise or it will slow down the race-to-idle for Deep sleep mode and hence cause a bit more battery drain just before deep-sleep state.

    Having location services enabled all the time isn't a good idea either, use it only when needed and keep GPS off otherwise. Samsung allows toggling of most things from notification panel so use it.

    Smart stay, smart pause, smart scroll all use the front camera for detection, which requires high voltage for operation(separate from CPU, uncontrollable by software) so keep them off unless needed.

    Make sure to keep your device clean. How does this affect battery life? Dust and other things when collected around pins, sockets and connectors prevent efficient passing of electricity and thus forces the device to demand more energy, around half of which is taken away by these. Even metallic dust can have adverse effect due to it making the transfer more rapid and forcing the battery to supply the power, which is most probably wasted.

    Automatic brightness is good during daytime, but useless during late evening and night, because brightness level doesn't need to be changed and it keeps the light sensor activated. Disable it after 7 Pm(you can also set up tasker or some other automation tool for this).

    An Odexed rom provides more battery life as compared to deodexed, but at the cost of available customization as no mods will work and will instead crash the file related to them. Choose your side wisely and patiently.

    If you're going to use some app, check if it uses GCM for providing notifications(usually google search at your service), if not look for an alternative which does. GCM doesn't even use marginal amount of battery and is more efficient in providing the notifications at time and also doesn't need a persistent notification.

    Check for wakelocks thoroughly and remove the misbehaving apps or hibernate them if you need them on your device. Also, be sure to update the apps for receiving any fixes and optimizations, which can sometimes also decrease the required wakelock frequency for an app and thus preserve battery life.

    Don't keep too much of auto updating widgets on homescreen, these only serve to drain the battery further by auto syncing.

    if rooted, use Xposed and boot-manager to disable unneeded apps at boot time and thus preserve battery and time required for full boot-up.

    If on a custom kernel use DAC direct(if available) for sounds. This bypasses the output mixer and thus preserves a little bit of battery required to produce and refine the sounds, instead utilize 128x oversampling and FLL tuning for an even better quality.

    Don't reboot on a regular basis unless needed, this will eat up battery life quicker.

    Don't use any task killer( a long debate on uselessness of those can be found on many sites, with a simple google search), the Android system's LMK is itself more than enough.

    Be sure to research carefully on what you really need and what you don't and then use it. Don't go on downloading useless things which you'll delete later on because it creates a small entry in /data/data which gets scanned by media scanner due to being present in its path and thus will make the process longer and more battery hungry.

    Some custom kernels allow for controlling deep sleep type. Usually these types are already defined in the kernel tweaking app itself. A person with heavy usage should use the IDLE deep sleep more so the device is able to wake up quickly and doesn't drain much battery in case of many wakelocks. Similarly a light user will benefit with AFTR+LPA due to CPU deep sleep, but this isn't advised for medium to heavy usage(use IDLE+LPA instead) because the wakelocks require a high power to even wake up the device, which will drain more battery if you use your mobile more, because many apps will try to acquire a partial/complete wakelock.

    I know this is quite long, but read through carefully and you'll surely get better battery life.


    Source : Experience and Google groups
    6
    Battery Calibration/Improving Battery life

    Requirements:
    Device needs to be rooted "Obviously".
    Need to have Rom Tool Box Lite or Rom Tool Box Pro.
    Some Basic Knowledge on how to use the app.


    Note: Turn off Wi-Fi, Bluetooth, GPS, and Auto-sync if they are not in use. Hold down the notifications bar to disable them and activate the Power Saving mode which will make the device conserve energy under low battery state.

    Battery Calibration Procedure.
    1. Use your phone until the phone battery drains out completely and device gets switched off
    2. Switch on the Device to make sure battery really is 0%.
    3. Now plug in charger (Device turned off, Dont turn on the device)& leave it for charging until it reaches 100%
    4. When the battery is full, switch on the phone, unplug the charger & check if the battery drops by 1 or 2% immediately.
    5. If you notice battery drops immediately plug in charger once more (while the phone is on) & let it charge completely.
    6. Once charging to 100% is done, don't disconnect the charger, open your root explorer, Provice RW permissions.
    7.Search for 'DATA' Folder then 'SYSTEM' Folder.
    8.In the 'System' folder you will find 'batterystats.bin' delete this file.
    9.Exit Root Explorer and Use your phone normally unless it completly drains the battery(Dont connect your charger)
    10.Power On your device and charge your device untill it reached 100%
    11.Now you should enjoy the Samsung long Battery Life!!

    Note: These methods are not permanent this worked for me so sharing with you.

    Greenify your Apps:

    NEW: Non-root working mode is now supported in 2.0+, Greenify is a convenient utility that will consequently hibernate battery hoarding applications that wait out of sight after you're done utilizing them.
    Google Playstore & Thread

    Titanium Backup:
    Great battery life, wonderful execution and cool customization— we have seen one or more applications for these things. Presently we should see an alternate must have and a standout amongst the most evaluated applications for established Android gadgets. On the off chance that you got root benefits on your gadget, Titanium Backup is an exceptionally suggested application for you. You may discover various reinforcement applications at the Google Play Store, however none of them does the employment so splendidly and pleasantly.
    Google playstore
    6
    The KERNEL can do some important things to help with battery saving as it is the controller of all things working in your phone:

    1. Underclocking - if you feel your phone is fast enough, go ahead and lower the maximum frequency of your CPU, it will save power as the faster the CPU goes, the more energy it uses.

    2. Undervolting - it's more complicated; every CPU requires certain amount of supplied voltage to run and the amount increases with the speed of CPU (clock frequency). For example 200Mhz requires only 0.9V while 1600Mhz requires 1.25V by default. The thing is, the higher the voltage, the higher the heat and of course power consumption. So the best way to lower it is to lower voltage - Samsung had to set voltage at the high enough level that every CPU they produce would work correctly but every CPU is different and some of them allow for lowering voltage and still remaining fully stable thus using less power to do the same work. Typically you can save about 0.05V but some CPU will allow as much as 0.1V to be saved. The same really goes for our GPU part, it can be undervolted as well. There are other parts in our phone that can be undervolted, like memory or controllers of various part but I have found (well in my phone) that saving were very small and caused instability so I would not recommend playing with them. We could think about undervolting our display as it is the biggest consumer of energy in our phone but actually we are doing it all the time The voltage supplied to the screen decides its brightness so if we were to lower the voltage it would just get dimmer
    3. There are small savings to be had in various other parts controlled by the kernel:
    - first and second thing are tied with SDcard - using it carries high power requirements - the less we use it, the better. Now we can't reduce to completely as all our data, apps and whole system is on it but we can reduce it's use by setting various caches.
    a) read cache for internal and external SD combined with scheduler that minimizes reads and writes - so far the best scheduler created specifically for mobile SD use is FIOPS, so using that with a large buffer (maximum of 4096) is actually the best from energy standpoint.
    b) system swap space - some kernels allow for creating a very specific kind of swap space, Android will use it once the free memory falls below certain point. Normally this swap space would be placed on SDcard but in this case it's inside a specific region of RAM. Why it is created like this? Because it can be easily compressed to keep more data, so basically we are using Android mechanisms and compressing memory so we can run more apps and keep them in physical RAM That means they are accessible faster than if we were to read them from SDcard and they use less power. Compressing and decompressing data as they go in and out of swap space is still far less energy consuming process then reading them from SDcard.
    - third is governor configuration - governor is a system service that decides at what frequency should the CPU be working at every moment and how much cores should be enabled - this of course has great impact on energy consumption and on the smoothness of our experience with our phone. There are two schools of setting up governor and they base their decisions on two premises:
    a) sharply increase CPU speed to get the work done fast and sharply decrease speed once it's not needed.
    b) slowly increase speed and only so much to do what must be don then slowly decrease speed once you are done because you may have to do something again in a moment
    There are pros and cons of both ways - way A means jumping to high frequency for a short time but high frequency uses comparatively large amount of energy, way B means slow increase but also means remaining in intermediate states for longer actually using energy for longer. I don't have any way to actually measure the resulting energy consumption but way A has a distinct advantage of creating much smoother experience so I use that myself.
    - fourth is hotplug configuration - our CPU can dynamically enable and disable additional cores - the process is called hotplugging. Some governors are created specifically for controlling this process, the best, as far as I have tested, in this is Lulzactiveq. Hotplugging has to be wise as to the IF and WHEN to enable and disable additional cores, it measures how many "packets" of data are in queue to be processed and based on short history anticipates increase and decrease of workload.

    All those interesting options are configured in scripts created for main contemporary kernels: Nadia, Devil and Agni and available HERE.

    Latest OC / UV Scripts for Devil / Agni and Nadia Kernels for Note 2 are HERE
    Guide to EXT4 to F2FS migration for Note 2 is HERE

    Courtesy:mad:Mat9V
    3
    非常有用的信息,谢谢 :好:
    2
    Good knowledge
    Thanx

    People are still spreading the batterystats.bin myth? *facepalm*

    This has been totally and utterly disproven many, many times, including by core Android developer

    So delete away. It doesn't calibrate or improve your battery life though.