Does Android automatically kill unused tasks?

[-Ollie-]

Hi all, Maybe I am misunderstanding something but I believe Android is supposed to automatically kill "unused" tasks after a while. Is that correct? I own a Galaxy S and I see that I still have in the running tasks list some apps that I haven't used for more than 18 hours. And these taks do not make any kind of auto sync, they communicate with the network only when used actively. Am I misunderstanding something?

 

[macprv]

Hi all, Maybe I am misunderstanding something but I believe Android is supposed to automatically kill "unused" tasks after a while. Is that correct? I own a Galaxy S and I see that I still have in the running tasks list some apps that I haven't used for more than 18 hours. And these taks do not make any kind of auto sync, they communicate with the network only when used actively. Am I misunderstanding something?

im not an expert but to my understand, android OS only kills a task whenever it feels like it needs more resources or memory.

 

[-Ollie-]

Thanks. But in this case, if some apps are not used at all for more than 24 hours, is it really saving battery to not kill them and keep them running in the background?

 

[Vehtemas]

Thanks. But in this case, if some apps are not used at all for more than 24 hours, is it really saving battery to not kill them and keep them running in the background?

Yes...

Quite simply because while they are in the background the majority of programs do not run, if they do run while the screen is off ALL of them can only use a max of 10% of the total processor.

Also say you kill a task and it then has to reload it, it takes more CPU to reload that program than it would if it just kept it in memory doing nothing.

It is very similar to how a computer runs with cacheing RAM, it holds the most used programs ready to go, which is why novel programs sometimes take longer to load.

 

[-Ollie-]

Got it, thanks!
One more question: how can Android know that some tasks are NOT to be killed ever without the use of a "task manager alike" program that would allow to build up an "ignore" (do not kill) list? I don't really have such apps right now (except gmail/calendar/contact sync, but I assume android already knows how to handle those), but there must be some apps that requires NW sync every x hours or maybe even x days.

 

[Demache]

Some apps, especially ones that pull information of the internet for syncing, run as a service in the background. They are pretty lightweight and only run when they need to.