FORUMS

PSA: You Can Optimize Your Note 4’s Recents Menu & RAM

The Note 4 never had the fastest Recents Menu, and despite its 3GB of RAM, … more

XDA Picks: Best Apps of the Week (July 25 – Aug 1)

Apps are at the front and center of any smartphone experience, and with over a … more

Voices Of XDA: Orbiting The Earth With Android

Editor’s note: This week’s feature has been written by forum … more

CloudPlayer: DIY HiFi Music Streaming Solution

In our Helpful Guide to Music Streaming Services, we mentioned several different services … more

[Q] More info on the Android OS bug. Suspend process , wakelocks and battery life.

34 posts
Thanks Meter: 6
 
By saejin2000, Member on 10th February 2012, 07:18 PM
Post Reply Subscribe to Thread Email Thread
Hello all,

I first posted this in Q&A on the home forum. There doesn't seem to be any interest so I thought I'd post it here again. Below is what I wrote on the original post.

"If you’ve been supremely annoyed with the AOS bug like I have , here’s some interesting information I’ve found (Did a search and it appears no one else has found this yet). It’s a paper written (in 2010)by Rafael J. Wysocki which touches deep into the subject. What I hope is that it will help some developers understand this bug and ultimately integrate a work around / fix as soon as possible. Hopefully this will help some users understand what is going on with their phones as well.

I have and Epic 4g Touch and all the ROMS I’ve tried have this bug but according to the article, looks like a kernel problem. My suspend / events/0 processes runs for a long time, eating up cpu and I don’t have it as bad as some people but thought it's worth mentioning.

Basically what I get from the paper is that…
1. The suspend (and by association the events/0 process) process is Google’s implementation of a power management system, an add on to the Linux Kernel
2. That the wakelock / suspend feature is , to make a long story short , not working the way it’s supposed to.
3. “Poorly” written apps, or apps that are written without the inner workings of how suspend /wakelocks work, will trigger this bug. This can be ANYTHING.
4. Supposedly, kernel version 2.6.37 will fix this. The Epic 4g Touch kernels are all .35 as far as I know which explains the fact that so many Epic 4g Touch owners complain about this.

Would love for the smarter than me people to give their take on this?

Since this is my first post, it won't let me post a link. Do a google search for Rafael Wysocki suspend_blockers.pdf and it should be the first link that shows up."

Hopefully there's more interest here!
The Following User Says Thank You to saejin2000 For This Useful Post: [ View ]
 
 
10th February 2012, 08:47 PM |#2  
Account currently disabled
Flag Anthony
Thanks Meter: 240
 
More
http://systemsens.cens.ucla.edu/~cs219/lectures/Suspend-Blockers.pdf
sent from the near past
Last edited by Danial723; 10th February 2012 at 08:50 PM.
11th February 2012, 03:17 AM |#3  
OP Member
Thanks Meter: 6
 
More
Danial, thanks for the reply. Not sure if it was intentional but that's not the document I was referring to. However it looks like useful info and simplifies some of the explanations and even uses the the document written by Wysocki as a reference so thanks for that.
12th February 2012, 04:48 AM |#4  
OP Member
Thanks Meter: 6
 
More
Bump! for battery life lovers!!!
12th February 2012, 04:16 PM |#5  
Senior Member
Thanks Meter: 75
 
More
how do I check to see if this bug is causing battery drain on my phone. thanks!

Sent from my SPH-D710 using Tapatalk
12th February 2012, 10:33 PM |#6  
OP Member
Thanks Meter: 6
 
More
Quote:
Originally Posted by pcmanager

how do I check to see if this bug is causing battery drain on my phone. thanks!

Sent from my SPH-D710 using Tapatalk

If you go to Settings, About Phone, Battery usage, you'll see "Android OS" take an unusal amount of battery time. Mine varies from 25-80%, some others I've read, consistently get 80%. You should be running on battery for a while before you check this since if you've only been on battery for a few hours, that stats may be misleading.

A more precise way is also to download the free Battery monitor Widget, and in the statistics section, you'll see the processes "suspend" and "events/0" take hours of usage when it shouldn't. You also may see *wakelock* take up hours of time.

Some dwho have it bad, download watchdog, and monitor on the fly, which processes go over a certain amount of % usage. If your batter drains quickly, suggest this route to confirm its suspend and events/0.
13th February 2012, 03:31 AM |#7  
Senior Member
Thanks Meter: 75
 
More
thanks for all those great infos. my android os is usually under 10 percent after several hours of use so I don't think that is buggin me. Could you explain exactly what a wakelock is? I know I could use the search button but the info you provide here in this thread might help a lot of other people trying to resolve battery drainage issues. Thanks!

Sent from my SPH-D710 using Tapatalk
13th February 2012, 04:21 AM |#8  
faceyourfaces's Avatar
Senior Member
Flag New York
Thanks Meter: 21
 
More
Quote:
Originally Posted by saejin2000

Hello all,
Since this is my first post, it won't let me post a link. Do a google search for Rafael Wysocki suspend_blockers.pdf and it should be the first link that shows up."

I'm assuming you were talking about this site, which was the second search result:
http://lwn.net/images/pdf/suspend_blockers.pdf

As a side note, my Android OS is at 7% of my battery usage right now.
13th February 2012, 06:03 PM |#9  
OP Member
Thanks Meter: 6
 
More
Quote:
Originally Posted by faceyourfaces

I'm assuming you were talking about this site, which was the second search result:
http://lwn.net/images/pdf/suspend_blockers.pdf

As a side note, my Android OS is at 7% of my battery usage right now.

May I ask,

1. How long your phone is on battery for?
2. Kernel Version?
3. ROM?

Would love to be @ 7% for Android OS!
13th February 2012, 06:47 PM |#10  
Senior Member
Thanks Meter: 75
 
More
1. How long on battery 1:15
2. Kernel Version EL29
3. ROM StrongSteve blue, Odex
4. Android OS 3%


I will let you know what the OS % is at the end of the day before the battery dies ......

Would love to be @ 7% for Android OS![/QUOTE]



Sent from my SPH-D710 using Tapatalk
13th February 2012, 07:02 PM |#11  
OP Member
Thanks Meter: 6
 
More
Quote:
Originally Posted by pcmanager

thanks for all those great infos. my android os is usually under 10 percent after several hours of use so I don't think that is buggin me. Could you explain exactly what a wakelock is? I know I could use the search button but the info you provide here in this thread might help a lot of other people trying to resolve battery drainage issues. Thanks!

Sent from my SPH-D710 using Tapatalk

A wakelock is, as I understand it, a process in the Android kernel that temporarily tells the Android device to hold off sleeping (stop the suspend process).

This allows for a process , application or device (such as your wi fi antenna) to turn back on and do what it needs to do. The suspend process is suppose to tell the phone to go back to sleep but with this bug, either or can get stuck and therefore use up more cpu that it's supposed to.
The Following User Says Thank You to saejin2000 For This Useful Post: [ View ]

Read More
Post Reply Subscribe to Thread
Previous Thread Next Thread
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes