Task Killers, are they a good thing?

OfTheDamned said:

With Android there is a difference between something running and something running in the background. Properly written apps close when you back out of them in Gingerbread. Some, like Pandora, have a quit or exit function in their menu. An app sitting in the background typically isn't really doing anything. In this state they are waiting for you to launch them again. An app that is using the CPU is a different story. If it is using the CPU then it is actually running at that time which means it is using the battery. You can see which apps are running too much or using too much battery in the battery stats under settings.

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Yeah, I use "Exit" whenever a program offers it (whether in a menu or by pressing Back twice or whatever). So, assuming it was written competently, an app that doesn't show as using significant power or CPU is truly dormant?

TinkerB3ll said:

If you are rooted you could freeze/defrost apps. Also look at firewalls such as droidwall or Lbe. I use the latter and it does as I require regarding controlling permissions.

Sent from my antique Speak & Spell running Froyo

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Those are some good ideas! I hadn't thought of freezing for this purpose but that'd do the job with less inconvenience than install-on-demand...

Found this in another thread...it helps answer my question:

rick311 said:

If you are rooted, you can download LBE Privacy Guard. It will allow you to pick and choose which apps can access certain parts of your phone. You can block facebook from accessing call logs, sms, mms, GPS etc...

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divinebovine said:

Found this in another thread...it helps answer my question:

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Most good custom ROMs (Kang/CyanogenMod) also have this feature, but you need to be careful what you restrict. It could easily send the app into a force close loop. FB uses those permissions for a reason:

SMS/Call Log: Do you sync your facebook contacts to your phone? This is necessary

GPS: Uploading a picture? FB may look for a geotag before uploading.


The only permission I ever recommend restricting is "Internet Access." This can block many of the pesky ads in games.

divinebovine said:

Yeah, I use "Exit" whenever a program offers it (whether in a menu or by pressing Back twice or whatever). So, assuming it was written competently, an app that doesn't show as using significant power or CPU is truly dormant?

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Some apps will "wake up" from a cached state to perform tasks if you set them to do so. Fetching updated material for RSS readers, checking for updates from facebook, uploading pictures to Google+, etc. These can all be adjusted in settings to be at specific times or only when connected to wifi. In general though an app or game will typically sit there doing nothing unless you select to open it.

ExtremeNerd said:

The only permission I ever recommend restricting is "Internet Access." This can block many of the pesky ads in games.

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Apps like Adaway will stop those too.

All these posts are convincing by their knowledge of the internal workings of Android.

But on my LG Revolution (368 MB usable RAM, Android v2.3.6), lag is (inversely) proportional to free RAM. When I get down to about 45-50MB of RAM, the phone is too slow to use.

After months of selectively stopping unnecessary running services (tedious, but I obeyed all the posts that say that Android manages RAM and I don't need to), I've resorted to killing all apps (using Superbox Pro's task killer) as the most expeditious way of ridding lag. I need to do this after about a half hour of apps use. Been doing if for about six months now, with perfect success (usually I see it go from 50MB to 110MB, and lag is instantly gone).

My results go against all the advice given here, but I'm not knowledgeable enough of the workings of Android to say why this seems so.

I *do* have too many apps (359), and maybe that is contributing to special circumstances on my phone.

jj2me said:

I *do* have too many apps (359), and maybe that is contributing to special circumstances on my phone.

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Well, that would do it.

Trying to make anything do something it was never really designed to do will cause problems. While a phone may be capable of having 350+ apps installed that doesn't mean it is a good idea. If your not using something on a regular basis, just uninstall it. It is easy to find and install again if you need it.

OfTheDamned said:

If your not using something on a regular basis, just uninstall it. It is easy to find and install again if you need it.

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...or save the APK on your SD card for install-on-demand.
...or freeze as TinkerB3ll said.

However, it sounds like jj2me has found what works for him. If it ain't broke (anymore) don't fix it (again), right?

divinebovine said:

...or save the APK on your SD card for install-on-demand.
...or freeze as TinkerB3ll said.

However, it sounds like jj2me has found what works for him. If it ain't broke (anymore) don't fix it (again), right?

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There is a differences between fixing something and slapping duct tape on it. Using a Task Killer is like sticking duct tape on your phone. It may work like that for a really long time, but it doesn't necessarily mean it is fixed.

@jj2me: Do you use many widgets? That is often the cause of lag on devices with limited RAM. Widgets insist on restarting even if the OS stops them to free up system resources for other operations.

Killing apps is always counter-productive. Very simply, you are only telling the OS it should try to reload frequently used apps into RAM, wasting CPU cycles and battery. IOW, the more an app is killed, the more the OS thinks you need it.

Just let Android do it's job, relax and enjoy your phone.

See:
http://lifehacker.com/5650894/andro...ed-what-they-do-and-why-you-shouldnt-use-them
...for a full explanation.

OfTheDamned said:

Trying to make anything do something it was never really designed to do will cause problems.

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I think that's it. Thanks. Maybe the OS stores significant app pointer information in RAM, to which it does not apply the vaunted Android memory management functions.

After spending about two hours culling, I got down to 328 apps. Still in hoarder territory.

I can't be sure yet, but after removing just those 30 apps, when I kill all tasks, it seems to free more RAM: I'm seeing 130 - 145 MB free now after a kill, compared to the 110 - 130 free after a kill that I was seeing previously.

Crashdamage said:

@jj2me: Do you use many widgets? That is often the cause of lag on devices with limited RAM. Widgets insist on restarting even if the OS stops them to free up system resources for other operations.

Killing apps is always counter-productive. Very simply, you are only telling the OS it should try to reload frequently used apps into RAM, wasting CPU cycles and battery. IOW, the more an app is killed, the more the OS thinks you need it.

Just let Android do it's job, relax and enjoy your phone.

See:
Android Task Killers Explained: What They Do and Why You Shouldn't Use Them
...for a full explanation.

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I try to avoid widgets, I think I only have three.

The linked article is helpful, thanks, though the only thing I could see that would apply is a bad app.

If I let Android do its job, the lag resembles a nearly frozen screen whenever I get in the territory of 45MB of free RAM. I can barely do anything at that point.

And the lag is proportional to free RAM (I can tell when I'm down to about 70 MB, definitely tell when it's 50 or below, and definitely tell 100 or above). It seems strange to see such lag-RAM proportionality exist because of a bad app. I have Watchdog installed and it's never alerted me nor displayed any bad app data. And when I previously stopped individual processes as a fix, I never noticed anything unusual. All my apps are well known, no oddballs, lots of Amazon FAOTD apps, all apps are from the Play Store or Amazon.

Is it imperfect memory management (Android didn't imagine there would be such an app hoarder installing so many apps on a device with so little RAM)? Or is it a bad app? I would have to slowly remove apps to test. If the RAM inches up as I remove apps one-by-one, then it seems to be the number of apps is the problem. If RAM lurches up significantly, or speed increases when I remove one app, then that's a bad app. Phew, I have work to do.

jj2me said:

Maybe the OS stores significant app pointer information in RAM,

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It does not.

...to which it does not apply the vaunted Android memory management functions.

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You misunderstand. When Android memory management is mentioned, that *is* regarding RAM memory, not data storage. And anything stored in RAM is subject to "the vaunted Android memory management functions."

I can't be sure yet, but after removing just those 30 apps, when I kill all tasks, it seems to free more RAM: I'm seeing 130 - 145 MB free now after a kill, compared to the 110 - 130 free after a kill that I was seeing previously.

Click to expand...

DO NOT kill apps! Re-read my previous message and the link in it. And remember, in the Android/Linux world, unused RAM is wasted RAM. High RAM usage is both normal and desirable.

The sheer number of apps installed has no impact on perfomance. It's what installed apps are doing that matters.

Crashdamage said:

It does not.


You misunderstand. When Android memory management is mentioned, that *is* regarding RAM memory, not data storage. And anything stored in RAM is subject to "the vaunted Android memory management functions."


DO NOT kill apps! Re-read my previous message and the link in it. And remember, in the Android/Linux world, unused RAM is wasted RAM. High RAM usage is both normal and desirable.

The sheer number of apps installed has no impact on perfomance. It's what installed apps are doing that matters.

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I understand RAM vs. internal storage. Former (10 years) developer here.

From your definitive answers that pointer information to apps is not stored in RAM (seems strange that that's not loaded at startup into the user portion of RAM, but what do I know?), and that *all* RAM is uniformly subject to whatever memory management functions that are applied (also seems strange, what with the GUI being a different animal from apps), I assume you know the Android OS code and defer.

Some info: "Running services" in Settings does not account for my LG's 368 MB of available RAM. It now says: "152MB used, 126MB free." (And when I try to hurriedly add up the individual processes that are displayed, it adds up to only 91.7MB.)

Regardless, your original advice to "Just let Android do it's job, relax and enjoy your phone" seems to miss the point of my original post, i.e., that I have a problem that seems highly correlated to RAM (one year's worth of observation). And your final advice to not kill apps, well, then I can't use my phone, it becomes unusable, or nearly so (it's even dicey whether I can answer phone calls at 45MB free RAM). Superbox Pro gives a "free RAM" function, which I imagine is doing something like what Android memory management does, but doesn't do anything observable to remove lag (as expected from our understanding of what the Android OS does to free RAM), gaining some MBs of reportable RAM, e.g., from 45 to 65, which is not enough to "enjoy my phone". Until I stop services, or kill apps. I have no other workaround. If it's a bad app, I have no indication of that.

jj2me - the problem being that it is most likely there are more apps trying to run on your phone than the RAM can handle. This is a more common problem on power users using lower end phones. Many apps have a background service flagged as "necessary" to run in the background. Examples of these are Dropbox and Sugarsync. Now, the problem could arise where you have a lot of these apps with processes flagged as necessary and in total they need more than your available RAM. Using a task killer with this aggravates the issue, since even before Android has a chance to learn which of these processes are absolutely necessary for your usage so it can kill them on its own, you are using task killers and thus flagged every process as necessary.

Honestly I don't know how you managed to put more than 350 apps on your device. I already have just over 150 and I almost used up my 2GB of dedicated app storage, and I have a higher end device than yours.

OfTheDamned said:

There is a differences between fixing something and slapping duct tape on it. Using a Task Killer is like sticking duct tape on your phone. It may work like that for a really long time, but it doesn't necessarily mean it is fixed.

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True. But if it gets the job done, and you don't mind the duct tape too long that might not be a problem.

Crashdamage said:

@jj2me: Do you use many widgets? That is often the cause of lag on devices with limited RAM. Widgets insist on restarting even if the OS stops them to free up system resources for other operations.

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Correction: I *do* use many widgets, I didn't realize my Folder Organizer icons were widgets. Thirty of them. I'll change to using Folder Organizer shortcuts, thanks.

chanchan05 said:

jj2me - the problem being that it is most likely there are more apps trying to run on your phone than the RAM can handle. This is a more common problem on power users using lower end phones.

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Yes, there seems to be indications that this is at least part of the problem. My usual practice of the last six months of task killing had never gotten me more than 150MB of freed RAM. But after removing ~30 apps yesterday, that same task killing just got me 216MB.

chanchan05 said:

Many apps have a background service flagged as "necessary" to run in the background. Examples of these are Dropbox and Sugarsync. Now, the problem could arise where you have a lot of these apps with processes flagged as necessary and in total they need more than your available RAM. Using a task killer with this aggravates the issue, since even before Android has a chance to learn which of these processes are absolutely necessary for your usage so it can kill them on its own, you are using task killers and thus flagged every process as necessary.

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Thanks for this explanation. I also change batteries about once a day. I assume this is equivalent to task killing, such that I should also avoid that practice, correct?

chanchan05 said:

Honestly I don't know how you managed to put more than 350 apps on your device. I already have just over 150 and I almost used up my 2GB of dedicated app storage, and I have a higher end device than yours.

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Right again. Sorry about that. I had mistakenly assumed that the App Dragon listing showed the number of apps (it starts "0/100", then "0/328", then the 0 increments up to 328). But when I actually count the apps, there are only 171 now, so probably about 200 before I removed a bunch yesterday. (Most are installed on my 1.5 GB of internal storage, as I frequently swap out SD cards containing media.)


Thanks, everyone. I will continue to remove apps and widgets, and from the incremental improvement I see from removing ~30 apps, I think that will solve the problem and I will have a real, usable smartphone again.

As long as you shutdown the phone properly before changing the battery (or let the phone shut itself down due to critical power level, no it won't count as "task killing".

Sorry, I can't leave this subject alone ;-)

All modern power phone users can avert their eyes now as this probably won't be of use or interest to you.

I do understand your frustrations as I suffered from the same issues for months when running Froyo on a 600mhz phone. Ie. Severe lag, interminably long system freezes, apps closing themselves whilst I was using them (browsers in particular) etc.
As you have noted yourself the problem *did* get worse as internal storage decreased - at times I had as little as 15mb free and struggled to try and keep it above 30mb. Yes, there is a difference between storage and ram and heap size etc. But lag did increase proportionally.

The advice to use as few widgets as possible is excellent as all widgets seem to take up a minimum of 15mb each.
Quite a few apps will start up extra services to keep them updated and such, taking up even more memory. There's usually nothing you can do about this other than find alternative applications.
Home screen replacements/launchers can cause lag - I had major problems with "Go launcher" until I replaced it with "Holo launcher"
Certain keyboards can be problematic too. My favourite keyboard "Swype" has over time been made unusable for me due to updates favouring newer os's and I had to revert to (the still wonderful) SwiftKey.
Autosynching apps can introduce extreme lag/stutter at inopportune times. For me it was calengoo calendar and gReader pro, both of which I now synch as and when required.

These issues made my phone frustratingly unusable for my first few months of ownership, particularly as similarly to you, I have circa 170 apps installed on an aging phone with limited memory and processing power. Finally I bit the bullet and rooted my phone which helped tremendously and made my phone usable once again. Moving apps to ext4 partition enabled me to not have to sacrifice the rather large apps I seem to grow fond of. As did integrating specific apps/updates into system rom. I used vmheap tool to treble my heap size which had an immediate positive effect. Freezing certain apps until I require them helped enormously too, particularly those that love to keep services running. Sdmaid cleared Oodles of junk from system, freeing up more storage space. Titanium backup is yet another essential in my battles against bloat and lag.

Overall I've found these measures affective for *me*, and as noted in an earlier post, I still have occasion to use a task killer (quick system info pro - using a whitelist) ) and make no apologies for doing so. I've found what works for me and am happy with my ageing phone nowadays. Do what works for you. My final (maybe) word on the topic is, if you are not rooted, bite the bullet and do so.

Good luck.

Tinkerb3ll, your ideas are intriguing to me and I wish to subscribe to your newsletter. What you've done is relevant to my interests. My low-spec phone is slow, has little storage, and has little RAM...and I like to pack-rat lots of apps. Rooting and using link2sd to move apps to an EXT3 (I went with what I know and I'm not familiar with EXT4) partition on the SD card has turned it from an underachiever into the little Android that could, but of course I'm looking for more.

Can you give me more details on these two ideas?

TinkerB3ll said:

As did integrating specific apps/updates into system rom. I used vmheap tool to treble my heap size which had an immediate positive effect.

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Which apps/updates integrated well into system ROM (by which, I assume, you mean the /system partition)?

Can you give me an overview (and maybe details) of the vmheap tool heap size adjustment? It appears that this is the tool in question:
https://play.google.com/store/apps/details?id=com.martino2k6.vmheaptool
How/why does it work, how do I use it optimally, etc...it's probably all in a thread you have bookmarked, pointing me in that direction will suffice.

Also, since you've apparently dealt with a lot of the same issues as me, do you have anything to add to my thread about my dalvik-cache clearing and rebuilding on reboot (which causes issues)?
http://androidforums.com/android-applications/619004-link2sd-not-re-linking-dalvik-cache-boot.html

Hi divinebovine, I'm afraid any newsletter I wrote would be of little use to anyone as nearly everything I've done has been as the result of research, experimentation, guesswork, and the work of others!

However, as you asked... My first tentative steps towards rejuvenating my aging phone were to integrate my own choice of browser and keyboard into internal memory, after which I froze the default apps in question and left them installed for a week to see how things worked. The aforementioned apps I froze caused no issues and I was able to un-install them eventually. I then tried freezing messaging, calendar, email, Gmail, live wallpapers, Google search, gallery, and music (I use my own choice of music player etc.) Freezing messaging, email, Gmail caused problems so I re-instated them and un-installed the others after a week of no problems.

Again, moving apps from/to system rom was a matter of experimentation along with a bit of juggling to see how things went. I found that if I could do without widgets for particular apps, or I could manage to put up with having to set apps as defaults on each boot, I could juggle a lot more but in the end I found I had to compromise with some apps and allow them to remain as system. I integrated all system updates into system too of course.

I then downloaded "vm heap tool" (from xda I think, though may be on market/play) and followed its recommendations and went from 32mb heap to 64mb (which oddly enough gave me 84mb heap, which despite my best intentions, I never got around to investigating why) This by itself seemed to make a huge difference to my system.

As mentioned in a previous post, I use "quick system info pro" to track my apps behaviour and see which causes stutter/lag, which processes restart if killed etc. This helps me decide what apps I should keep, which I should freeze/defrost as required, and which I can safely kill as desired (I will continue killing apps despite all the documented evidence I shouldn't as it works for *me*)

I hope my disjointed ramblings are of some use to you and I wish you good luck in your endeavours.

I highly recommend: titanium backup pro and clockwork mod, as they gave me the confidence to throw apps hither and thither safe in the knowledge I could always rollback. Vm heap tool worked wonders for me so consider trying it. Sdmaid cleared up for me with narry an issue. Quick system info pro is perfect for me - though you may prefer a more up-to-date application. For all the aforementioned apps I salute the developers whose abilities and talents seem to be so far beyond anything I could hope to do.

Unfortunately, your dalvik cache issues are not something I've come across before and I'm sorry I can't offer help or advice on the matter though I do wish you the best of luck in resolving them.

Your disjointed ramblings are very helpful, they put a lot of stuff I was thinking about in one place and fill in the blanks...it's not a step-by-step howto but that's not what I was looking for anyway; you've given me direction that I need to do the necessary experimentation.

Also, the "newsletter" thing is a little internet joke, an oft-used quote from The Simpsons.

Ahoy-ahoy! Good luck and have fun.

sometimes my phone becomes short of RAM and terminates some of apps that i dont want to be stopped like multiscreen wallpapers and battery% , and you guys are saying that let android do his work but its really annoying when android terminates some apps that i dont want him to terminate , what should i do now? please help

NafeesAhmed said:

sometimes my phone becomes short of RAM and terminates some of apps that i dont want to be stopped like multiscreen wallpapers and battery% , and you guys are saying that let android do his work but its really annoying when android terminates some apps that i dont want him to terminate , what should i do now? please help

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Yeah i understand that man. It should learn what you use most but it isnt perfect. I think there are apps where you can "white list" certain apps that you want to give priority to so that they stay in ram.
Hopefully someone can give some links :thumbup: