Only the CPU takes up battery?

[jamesino]

I recently learned that I should not use a task killer such as advanced task killer to save battery.

Instead, I downloaded WatchDog Lite, a CPU monitoring device that shows how much CPU each app/task is using. Is it correct to say that the amount of battery a certain app takes up is proportional to solely its CPU utilization and not how much RAM/memory it is using?

For example, if a program is displayed as using 0.0% CPU and 100mb of RAM, does it mean that it's just idling in the background and not consuming any battery life?

Similarly, if I was playing a game such as Angry Birds or World of Goo, or using an App that does not have an exit button, and I hit the home button to return to home screen, is that good enough to close the program? When I hit the game again, the game restores to where I left off, so it seems like as if I only paused the game when I hit the home button. Is the game still taking up battery power in such a situation where I just minimized it using the home button? If so, then what is the proper way to shutdown the application?

Thanks.

 

[Paul627g]

Yes your correct, stay away from the 3rd party task killers. The built in app management is very efficient.

By exiting an app using HOME then yes your leaving it running in the background. It will be using some juice up because even though its lying dominant its still running. At least this is how I view it.

Proper way to exit an app is find the way the app developer has intended you to exit. Normally via a menu in the app or other means to exit/quit the application. Just about every app out there has a way to exit it properly, problem is some developers I think make this difficult and you may have to hit a few menus and on screen button presses to complete the action.

I know Angry Birds does have an exit, I always have to find it so I can exit it properly after my kids get thru playing it.

 

[Srambo217]

I always try to throttle my idle data connections to save battery. In my opinion that's what causes bigger idle battery drains.

Turning off auto-sync helps, and you will see positive results using apps like GreenPower Premium or JuiceDefender which prevent 3G/4G connections while your screen is off.

Sent from my SCH-I535 using Android Central Forums

 

[funkylogik]

all true but remember screen is your biggest killer so train your eyes to get used to under like 5% brightness when indoors.
task killers are throwbacks from Eclair IMO

global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess

 

[jamesino]

Thanks guys.

What about apps like Pulse or Flipboard? There doesn't seem to be an Exit or Quit button in any of the menus.

Is my only option to simply kill the task using WatchDog?

Also, just to clarify again; even if I do just minimize a certain app without finding a way to properly exit out of it via a menu, and watchdog is displaying that the app is consuming 0% CPU and say, 90mb of RAM, that app is not using any battery right? RAM consumption without CPU utilization means the app is not sucking up any battery?

 

[Paul627g]

You maybe right on the CPU consumption, if that is what its saying then it maybe true.

Funky brought up a great example of conserving battery which is screen display brightness. I ALWAYS disable the auto brightness feature and run at around 20% or less... This works great for most situations. Only time I power up to full brightness on any device is outdoors.

 

[funkylogik]

what i say to everyone is just trust android to handle its memory.. its pretty good at it

global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess

 

[johnnyshinta]

I just installed watchdog to keep an eye on rogue processes. I don't really care about ram since I have plenty. But there are apps that will be running in the background at their full potential I guess. If an app is in the background it shouldn't need more than a few % points to stay up. If it's running at like 50% there is an issue.

 

[funkylogik]

I just installed watchdog to keep an eye on rogue processes. I don't really care about ram since I have plenty. But there are apps that will be running in the background at their full potential I guess. If an app is in the background it shouldn't need more than a few % points to stay up. If it's running at like 50% there is an issue.

think il try that app mate. is it any better/worse than Cpu Spy? (havent tried either)

global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess

 

[lbkiml]

My screen brightness is around 25%, works in most cases except when its sunny outside.

Like someone else said, throttling data connection helps, especially in fringe areas. I always turn off data at work because of the lack of reception in our builing, and to not get distracted while working

 

[johnnyshinta]

think il try that app mate. is it any better/worse than Cpu Spy? (havent tried either)

global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess

Looks like cpu Spy tells you how long the CPU was running at half capacity or low power state or maxed out. Watchdog tells you which apps are using cpu and if they are running in the background

 

[funkylogik]

cheers. im gona download watchdog now (if its free)

...great app man. wow Speak It Is usin a lot of CPU (9.5%) n i really like that app for reading my texts
wonder if theres anythin more efficient that does same job. i dont see why its hogging so much while not even reading anything.. might keep it switched off until im walkin with headphones in..

global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess

 

[johnnyshinta]

I tried cpu Spy and it's got good info. Tells you how long your cpu is in what state. But it doesn't tell you what is keeping it from going to sleep. And the timer doesn't reset after every charge. Only after boot up.

Watchdog seems to be a beast... Pun intended

 

[johnnyshinta]

Hey funky. Do you find watchdog compliments Gsam battery monitor or kinda duplicates it'd function.

I'm finding it a little redundant

 

[johnnyshinta]

I'm also trying out system panel. It has ever start under the sun. Cpu stats, battery stats, memory stats, app usage. The works.

 

[funkylogik]

id say it compliments slightly but i probably wont keep watchdog active all the time, just every so often to check things out, the fact that it has an alert notification when an app "misbehaves" is pretty cool though.
yeah ive got system panel (EDIT its Android Assistant ive got) but havent got round to playin with it yet mate..

global s3, UK. Ask me anything and ill reply even if its just an intelligent (or stupid) guess

 

[Steven Todd]

Hey there, not sure if this thread is dead, but im kind of new to Android cusomization. I had a question about the CPU, im using an app called SetCPU (for rooted devices) and it allows me to set cpu minimum and maximum state, allowing me to underclock and save battery life.

i was wondering if i even needed to do that, or if android uses its processor on demand? like will it use minimum for just being idle and use what it needs for games and such, or is it always maxxed?

thanks for the help in advance.

 

[meyerweb#CB]

Android does vary the cpu speed on demand. That said, SetCPU can still be useful.

For example, with the screen off, certain activities running in the background will still cause the CPU to throttle up. With SetCPU you can create a profile that limits the CPU to the minimum speed whenever the screen is off, preventing background processes from causing the CPU to speed up. Those processes will run slower, but if you're not actually using the device and waiting on them, does it really matter? How much difference in battery life this makes will depend, I suppose, on how many background processes are running, how often, and what they do.

You can also use SetCPU to limit the maximum CPU speed, forcing underclocking all the time. This will slow your phone down, but if battery life is more important to you than performance it can be useful. Or you can compromise: create a provide that limits clockspeed when the battery drops to less than 50%, or 30%, or whatever makes sense to you, thereby extending battery life a bit when you start to run low. You can also limit clockspeed if the battery gets too hot.

Conversely, you can force the maximum clock speed when the phone is plugged in, charging, taking advantage of the maximum performance of the device when you don't really need to save battery.

Here are my profiles. Note that they are in priority order, so "Screen off" will always set the CPU to the slowest speed, regardless of battery or charging state. And the "Charging Any" profile will only take effect if the battery is above 25%. (I figure if the battery is really low, I want the juice going into charging the battery, not cranking up the processor.)