Executive summary = You always want "Keep Wifi on During Sleep" set to "Always" if you care about your battery life.
In post #17 in the "P6210 - Huge Battery Drain on ICS" thread iosandroid found that setting "Settings->Wifi->Menu->Advanced->Keep Wifi on During Sleep" to "Never" caused battery drain. Since I feel this is big bug and my mom told me I'm special I thought I'd start a new thread with some more details on this problem, a more descriptive thread title to highlight this issue and a few questions of my own.
I have a Samsung Galaxy Tab 7.0 Plus (aka GT-P6210) WiFi only tablet that had HC (Honeycomb) when I first got it. To save battery I changed "Settings->Wifi->Menu->Advanced->Keep Wifi on During Sleep" to "Never" (actually think the wording was a little different back in the HC days, but you get the idea). I'm not sure if/how much this helped, but it didn't hurt my battery life.
Shortly after upgrading to ICS (Ice Cream Sandwich) I noticed my battery life was worse. Apparently I wasn't alone since "iosandroid" (see above) had the same problem and solution. That is, if you set Settings->Wifi->Menu->Advanced->Keep Wifi on During Sleep" to "Never" or "Only when plugged in" your better drains much faster when you're tablet is idle. How much faster? In my tests setting this to "Never" drained my battery by 3.10%/hour. If I leave this at its ICS default of "Always" my battery only drains at 0.27%/hour, OVER 10 TIMES BETTER (idle) BATTERY LIFE! See the bottom of this post for a listing of my battery drain tests.
By using "CPU Spy" I could see that with "Keep Wifi on During Sleep" set to "Never" my tablet would never go into deep sleep, but with it set to "Always" my tablet would spend almost all of its time in deep sleep. GSam Battery Monitor showed that "Kernel (Android OS)" was using up most of my battery when this problem is occurring.
This problem isn't limited to ICS, I also got the same results with JB (Jelly Bean). Specifically I used "AOKP Jelly Bean Milestone 1". With stock ICS the default setting is "Always", so only people that mess with their advanced settings will be affected by this. Note that I believe that an OTA upgrade from HC to ICS will retain your previous settings for this. In JB (at least AOKP JB), this problem will have a much wider reach since "Keep Wifi on During Sleep" defaults to "Never".
Now on to my questions:
-Does anyone know the scope of this bug? Does it only affect the P6210, or Samsung devices, or every Android device? iosandroid reported having the same problem with his phone.
-Do I have to open a tech support case with Samsung to report this bug, or is there a better way?
[Battery Drain Tests]
VERSION Keep Wifi on During Sleep? DRAIN RATE
----------------------------------------------------------------------------------------------
HC Always 1.00%/hour (lost 2% total over 2 hours)
HC Never 0.50%/hour (lost 1% total over 2 hours)
ICS Always 0.27%/hour (lost 2% total over 7.5 hours)
ICS Never 3.10%/hour (lost 24% total over 7.75 hours)
JB Always 1.0%/hour (lost 1% total over 1 hour)
JB Never 3.52%/hour (lost 81% total over 23 hours)
-Legend
--HC = Stock Honeycomb (Android 3.2)
--ICS = Stock Ice Cream Sandwich (Android 4.0.4)
--JB = AOKP Jelly Bean Milestone 1 (Android 4.1.2)
-Setting "Keep Wifi on During Sleep?" to "Only when plugged in" behaves the same as "Never" (i.e. it has same battery drain problem)
-Yes, I know my testing time periods vary wildly, but I'm too impatient to wait a day for each of the tests. For example I'm sure JB's "Always On" loss rate is much closer to ICS's.
All I can say or add to this my tenderloin HP touch pad running cm is the same keep wifi on always drains the battery slower than never.
IMO, it would be because of 3G activating when the wifi turn off during sleep.
Try doing your test in Airplane mode to isolate the activation of the Phone radio and stick only to WIFI during your comparison test.
EDIT: ooops! sorry, it just occured to me that you've got a P6210 and not a P6200. My bad.
Airplane mode uses more battery than WiFi always on
viper001 said:
Try doing your test in Airplane mode
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Click to collapse
Yup, my tab is WiFi only. However I did actually test it in airplane mode and found that the battery lost 0.40%/hour (lost 11% total over 27 hours) with airplane mode enabled. This is still worse than the 0.27%/hour you lose when you just leave WiFi on (Keep Wifi on During Sleep? set to Always). This airplane mode battery drain was also unexpected to me, but in googling it seems like this is a common problem.
One last test I did was to manually turn the WiFi off. When I did that the battery only drained at a rate of 0.11%/hour (lost 1% total over 9.5 hours). I should test that longer to get a more precise number, but my short test was good enough to show that manually turning WiFi off does actually save power (it's about time something worked as I expected it to .
My next planned test it to use something like AutomateIt to automatically turn off the WiFi after the screen turns off to see if I can automate the WiFi battery savings.
My GT-P6210 also has the same issue after installing Elements HD rom. I never had this issue even after upgrading from honeycomb to ICS stock.i
jim-j said:
Yup, my tab is WiFi only. However I did actually test it in airplane mode and found that the battery lost 0.40%/hour (lost 11% total over 27 hours) with airplane mode enabled. This is still worse than the 0.27%/hour you lose when you just leave WiFi on (Keep Wifi on During Sleep? set to Always). This airplane mode battery drain was also unexpected to me, but in googling it seems like this is a common problem.
One last test I did was to manually turn the WiFi off. When I did that the battery only drained at a rate of 0.11%/hour (lost 1% total over 9.5 hours). I should test that longer to get a more precise number, but my short test was good enough to show that manually turning WiFi off does actually save power (it's about time something worked as I expected it to .
My next planned test it to use something like AutomateIt to automatically turn off the WiFi after the screen turns off to see if I can automate the WiFi battery savings.
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Click to collapse
If you know how, try looking into the build.prop. you'll find that stock wifi. supplicant_scan_interval=15. try a higher number like 90 or 180. this basically lengthens the time for wifi network searches from 15 secs to 90 or 180 seconds respectively.
As Krusty the Clown says, "it's not just good--it's good enough"
viper001 said:
If you know how, try looking into the build.prop. you'll find that stock wifi. supplicant_scan_interval=15. try a higher number like 90 or 180. this basically lengthens the time for wifi network searches from 15 secs to 90 or 180 seconds respectively.
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Click to collapse
I could probably figure out how to change that, but I've decided that just leaving WiFi on all the time gives me good enough battery life. I enjoy troubleshooting these types of technical problems, but unfortunately I must return to debugging my three year old daughter's Dravet Syndrome. Her cognition is deteriorating, so I'm hoping to find a solution or workaround soon. If any of the multimillionaires that read this forum want to fund a cure for Dravet Syndrome, head on over to dravet.org or dravetfoundation.org
I've got this issue on a Chinese Tablet running JB 4.1.1. After some investigation the conclusion I've reached is that the settings are mislabled on the GUI. "Always" results in disconnection from the SSID 15 minutes into sleep (although WIFI is still 'ON'). "Never" keeps WIFI on and connected indefinitely, and if autosync is also on you'll get lots of wake-locks and reduced standby battery life, particularly if you have location reporting on and google maps installed.
neu - smurph said:
I've got this issue on a Chinese Tablet running JB 4.1.1. After some investigation the conclusion I've reached is that the settings are mislabled on the GUI. "Always" results in disconnection from the SSID 15 minutes into sleep (although WIFI is still 'ON'). "Never" keeps WIFI on and connected indefinitely, and if autosync is also on you'll get lots of wake-locks and reduced standby battery life, particularly if you have location reporting on and google maps installed.
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Click to collapse
Interesting results, but that wasn't my experience. For example with WiFi always on my tablet does stay connected to the network all the time. All of these weird issues is about enough to make you want to buy an iPad.
I have been using my N5 for a couple of weeks and I know its battery life isn't the greatest. I have watched some youtube videos for tips on better battery life, and here's what I have done.
Turn off auto brightness, and screen brightness is about 1/4 of the way
Turn off haptic feedback
Turn off vibration on keypress
Turn off sync for most Google services
Turn off NFC
Location service set to battery saving mode
But it seems like after all that's been done, the battery is still draining pretty fast. For example, I went out for dinner and drinks with friends and my phone is just sitting in my pocket the whole time not being used, 4 hours later, I have lost 30% battery. Coming from an htc one, it doesn't drain nearly as much. Is this abnormal or just about right for the N5, thoughts?
Infiniteloop7 said:
I have been using my N5 for a couple of weeks and I know its battery life isn't the greatest. I have watched some youtube videos for tips on better battery life, and here's what I have done.
Turn off auto brightness, and screen brightness is about 1/4 of the way
Turn off haptic feedback
Turn off vibration on keypress
Turn off sync for most Google services
Turn off NFC
Location service set to battery saving mode
But it seems like after all that's been done, the battery is still draining pretty fast. For example, I went out for dinner and drinks with friends and my phone is just sitting in my pocket the whole time not being used, 4 hours later, I have lost 30% battery. Coming from an htc one, it doesn't drain nearly as much. Is this abnormal or just about right for the N5, thoughts?
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Click to collapse
7.5%/hr is high for standby time. You can get it down to 1-2%/hr by using more of the battery-saving tips you'll find in the various threads on the subject.
Sent from my Nexus 5
Check the wakelock with better battery stat
If you don't need GPS on all the time turn that off too saves quite a bit of battery even the battery saving mode isn't that battery friendly
Sent from my Nexus 5 using Tapatalk
Infiniteloop7 said:
But it seems like after all that's been done, the battery is still draining pretty fast. For example, I went out for dinner and drinks with friends and my phone is just sitting in my pocket the whole time not being used, 4 hours later, I have lost 30% battery. Coming from an htc one, it doesn't drain nearly as much. Is this abnormal or just about right for the N5, thoughts?
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Click to collapse
You really need to share your battery usage screen, and show what apps drained your battery. It is possible that you were had low signal strength, and so your phone kept trying to search for a signal and drained itself. Also, as dark_ente suggested, look at betterbatterystats results to see if you had wakelocks.
With no active use, that is very high drain - unless you were in a very low signal strength area, or had an app keeping your phone awake.
When I work from home, connected to WiFi, my phone drains about 3-4% in about 9 hours (assuming I don't actively use it. I use pushbullet to show me all notifications on my PC, so I don't have to turn my phone on at all)
Infiniteloop7 said:
Turn off auto brightness, and screen brightness is about 1/4 of the way - I do the same (actually, I set it to the lowest possible level), because it is too bright
Turn off haptic feedback - I do the same, because it is annoying
Turn off vibration on keypress - I do the same, because it is annoying
Turn off sync for most Google services - I leave sync on
Turn off NFC - I leave it on
Location service set to battery saving mode - I do the same - but set up a tasker profile to enable GPS when I launch maps - Disabling GPS helped the most in my case
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Click to collapse
jj14 said:
You really need to share your battery usage screen, and show what apps drained your battery. It is possible that you were had low signal strength, and so your phone kept trying to search for a signal and drained itself. Also, as dark_ente suggested, look at betterbatterystats results to see if you had wakelocks.
With no active use, that is very high drain - unless you were in a very low signal strength area, or had an app keeping your phone awake.
When I work from home, connected to WiFi, my phone drains about 3-4% in about 9 hours (assuming I don't actively use it. I use pushbullet to show me all notifications on my PC, so I don't have to turn my phone on at all)
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Click to collapse
When you say turning off GPS and only enable it while launching maps, do you mean turn off location completely? Does that affect other Google apps/services? Such as Google now
If all else fails, do a factory reset.
Sent from my Nexus 5 using xda app-developers app
I noticed from the past few days that my N5 seems to have abnormal battery usage pattern. There are days with mostly light use (text messaging, whatsapp messaging, some web browsing, minimal on screen time) I can go for 2 days without charging, and I am only losing 1% battery per hour when it's in stand by. However, they are times (see attachment) when I didn't use my phone for 11 hours, and the battery level is down from fully charged to 26%. Can anyone give me some ideas on what may be the culprit?
kevtrysmoddin said:
If you don't need GPS on all the time turn that off too saves quite a bit of battery even the battery saving mode isn't that battery friendly
Sent from my Nexus 5 using Tapatalk
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Click to collapse
battery saver mode is actually very battery friendly. i've done extensive testing...
---------- Post added at 06:25 PM ---------- Previous post was at 06:24 PM ----------
Infiniteloop7 said:
I noticed from the past few days that my N5 seems to have abnormal battery usage pattern. There are days with mostly light use (text messaging, whatsapp messaging, some web browsing, minimal on screen time) I can go for 2 days without charging, and I am only losing 1% battery per hour when it's in stand by. However, they are times (see attachment) when I didn't use my phone for 11 hours, and the battery level is down from fully charged to 26%. Can anyone give me some ideas on what may be the culprit?
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Click to collapse
you need 'better battery stats' log. . . stock battery screen tells you almost nothing
Infiniteloop7 said:
When you say turning off GPS and only enable it while launching maps, do you mean turn off location completely? Does that affect other Google apps/services? Such as Google now
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Click to collapse
No. I keep location enabled all the time, but in battery saver mode - that way, google now, weather widgets etc can get my approximate location (using cell tower triangulation), but can't activate my GPS for accurate location fix.
When I use maps/navigation (which in my case is the only time when I need accurate GPS location fix), I change from battery saving location to the GPS type location fix, and when I'm done with maps/nav, I switch back to battery saving location.
If you turned location off completely, google now, and possibly other apps (like weather widgets for current location) won't work.
Infiniteloop7 said:
I noticed from the past few days that my N5 seems to have abnormal battery usage pattern. There are days with mostly light use (text messaging, whatsapp messaging, some web browsing, minimal on screen time) I can go for 2 days without charging, and I am only losing 1% battery per hour when it's in stand by. However, they are times (see attachment) when I didn't use my phone for 11 hours, and the battery level is down from fully charged to 26%. Can anyone give me some ideas on what may be the culprit?
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Click to collapse
From your 2nd screen print, you can see that your phone was awake pretty often. As @Enddo wrote, betterbatterystats should help you figure out what is causing the wakelocks.
Enddo said:
battery saver mode is actually very battery friendly. i've done extensive testing...
---------- Post added at 06:25 PM ---------- Previous post was at 06:24 PM ----------
you need 'better battery stats' log. . . stock battery screen tells you almost nothing
Click to expand...
Click to collapse
jj14 said:
No. I keep location enabled all the time, but in battery saver mode - that way, google now, weather widgets etc can get my approximate location (using cell tower triangulation), but can't activate my GPS for accurate location fix.
When I use maps/navigation (which in my case is the only time when I need accurate GPS location fix), I change from battery saving location to the GPS type location fix, and when I'm done with maps/nav, I switch back to battery saving location.
If you turned location off completely, google now, and possibly other apps (like weather widgets for current location) won't work.
From your 2nd screen print, you can see that your phone was awake pretty often. As @Enddo wrote, betterbatterystats should help you figure out what is causing the wakelocks.
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Click to collapse
I am still pretty new to Android and I don't know how to root my phone. I did check out betterbatterystats on google play, it says the app doesn't work on non-rooted Android phone running kitkat, that's why I haven't installed it yet. It seems that kitkat made some changes which prevent battery usage apps from working properly, wake lock detector also won't work on non-rooted phones running kitkat
Infiniteloop7 said:
I am still pretty new to Android and I don't know how to root my phone. I did check out betterbatterystats on google play, it says the app doesn't work on non-rooted Android phone running kitkat, that's why I haven't installed it yet. It seems that kitkat made some changes which prevent battery usage apps from working properly, wake lock detector also won't work on non-rooted phones running kitkat
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Click to collapse
Rooting is pretty easy. And it opens up a whole new world.
________________________
Sent from my Nexus 5
Infiniteloop7 said:
I am still pretty new to Android and I don't know how to root my phone. I did check out betterbatterystats on google play, it says the app doesn't work on non-rooted Android phone running kitkat, that's why I haven't installed it yet. It seems that kitkat made some changes which prevent battery usage apps from working properly, wake lock detector also won't work on non-rooted phones running kitkat
Click to expand...
Click to collapse
While betterbatterystats will work on kitkat (unrooted), it won't give you partial wakelock summary That requires root)
http://forum.xda-developers.com/showpost.php?p=15869904&postcount=3 - see FAQ 1 and 3. You can download the kitkat compatible version from http://forum.xda-developers.com/showthread.php?t=1179809
As PhilipTD wrote, rooting a N5 is pretty easy, but if you don't feel comfortable doing it, don't.
If you decide to root, follow the steps in first post at the link that PhilipTD provided.
Note that Step 1 (unlocking bootloader) will wipe out all your data.
Before you root, why not disable GPS (keep location active) and see if that helps? Also, how often do you reboot your phone?
I've only had my nexus for a week now and I'm trying to hunt down the reason I'm getting poor battery life. At first it was nlp wakelocks but that went away on its own somehow. Now its my wifi draining battery, in 8 hours of idle overnight it went from 100% to 79% and wifi was the top usage. I've never seen this before on any phone with any rom so I'm not sure what to do about it.
Hi,
Try Settings/Wi-Fi/Menu/Advanced/ and untick Scanning always available...
This is what I did to improve my battery:
1. Location Services : If you are not in a neighborhood with a lot of wifi spots you will most likely feel this draining your battery life. Under settings make sure that Location Services is set to battery saving and not High accuracy.
2. Widgets : Weather widgets, games eat battery by constantly fetching information . Check the settings for these widgets and make sure they are using wifi and not updating the weather information every 30 mins or so. I keep my settings to update weather information every hour to keep it reasonable. The Gmail widget sometimes eats your battery too. I removed the widget and used an icon in the dock at the bottom to check my email. Another thing I noticed was that some widgets are just more battery intensive than others. For example I found HD widgets consumed nearly twice as much battery as Chronus on the home screen but both displayed the same information.
3. Restart your phone : Sometimes residual processes from closed apps could cause issues. Restart your phone if you haven't done it in a while and it should clear up any unnecessary things.
4. Keep wifi on during sleep : I made sure my phone uses wifi even when its sleeping. 3g / 4g eats the battery like crazy if you turn off wifi when your phone sleeps. This should be a default setting as pointed out by some users. In my case it had been changed probably when I was tinkering with the phone. You can find this setting in the Settings -> Wifi -> advanced -> Keep wifi on during sleep.
You can also use apps like Greenify , Tasker , and Llama.
5. Don't use Automatic Brightness : Turns out if the sensors are constantly looking to adjust brightness it takes up more battery. I set my brightness at around 60% and it works just fine throughout the day.
6. Use wifi over 3G/4G/LTE if possible
7. Switch off wifi when using Data: Android doesnt switch off your WiFi when you use data because Google wants you to use it for Locations and help build their database of networks.Switch off WiFi completely when using data to save a good chunk of battery.
8. Turn off Vibration on touch : Typing uses quite a bit of battery over the course of a day. Try switching Vibration on touch off.
9. Use Franco Kernel: : This will require rooting your device however it makes it a lot more power efficient.
10. Turn down the Facebook refresh rate : Make sure it updates not very often( every 3-4 hours) or never. IMO your phone is better off without Facebook or any other battery hog social networking apps.
I found airplane mode with Wifi on consumes a lot of battery (standby with screen off).
Below is the battery drop of one night (about 7 hours), using the latest official rom [G920FXXU2COH2] for G920FD.
- Case 1
Turn the phone into airplane mode and turned on the WiFi. About 50% battery drop for one night.
- Case 2
No airplane mode. Both WiFi and mobile networks are connected. About 3% battery drop for one night..
I don't know why this happens. Can anyone confirm that and tell me the cause to the battery drop. Is this a baseband problem?
Probably there is some app connecting to internet and because of Airplane mode it causes massive wakelock.
Could you post some wakelock stats by gsam or wakelock detector?
^^^ This. You need to find out what's causing wakelocks on your phone. It's probably an installed app.
It's possible you're running too many unnecessary apps in the background. Try searching on xda for this app called Purify. It showed I was running 17 unnecessary apps that I didn't use frequently. It needs root but it works magic. Let me know what you think. Btw it's not my app. Just something I stumbled on, on my search to save my battery life. I gained about 1 to 1 1/2 hours of screen on time. I have about 300 apps on my phone and I'm a rooted power user.
Oh, my phone used to lag from time to time when trying heavy multitasking. Not anymore. To each his own.
Sent from my SAMSUNG-SM-G925A using XDA Free mobile app
As the title says... is there something wrong with my battery? I got abysmal SOT of 4hr35min on mobile/cellular data only (No WiFi). Bluetooth OFF, location OFF, dark mode OFF, brigtness 40% or less, Samsung Cloud, Google Photos & Google One back up & sync - all OFF,. Bixby home, bixby wake up, literally everything bixby related OFF. Wake to lift OFF, smart stay OFF. Optimized battery settings, exceptions to optimize made on gmail, whatsapp, instagram. Everything else on optimization. AoD - always on, dynamic background on home screen - yes.
Also worth noting - after fully charging the phone, I went from 100% to 98% in like 3 minutes. I also went from 5% to 0% in a couple of minutes.
Is there something wrong with my battery? Surely 4 hrs 35min shouldn't be a norm, not even on cellular data only.
Signal Strength plays a huge rule in battery consumption, ever thought about that??
How many dBm's you get?
Mohamedkam000 said:
Signal Strength plays a huge rule in battery consumption, ever thought about that??
How many dBm's you get?
Click to expand...
Click to collapse
Where can I check dBms?
furiouszagreb said:
Where can I check dBms?
Click to expand...
Click to collapse
Settings > About phone > SIM stats > Signal Strength
Mohamedkam000 said:
Settings > About phone > SIM stats > Signal Strength
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Click to collapse
It was in between -87dBm to -104 dBm. Screenshot provided. I honestly doubt its a signal, but cellular data really doesnt give me more than 5hrs SOT which is really bad....
First of all, I did a factory reset. Then, I did 100% do 0% and then charged the phone while OFF to 100% again and other time I did 100% to 0% and charged it while turning it on after couple %.
I also disabled EVERYTHING Bixby related AND I disabled Facebook running in the background.
The result are in, aaaaaaand.....
MASSIVE IMPROVEMENT!
I am now getting at least 7hrs 30mins with 70%/30% wifi/mobile data usage.
On WiFi Only, I can now get EASILY 9 hours SoT
See screenshots - #1 & #2 showing 7hrs 30mins wifi/mobile data. Screenshot #3 WiFi only, 8hrs 22mins WITH 22% battery to spare! So, easily 9 hrs SoT...