I'm writing an app that has a foreground service, content provider, and a Activity front end that binds to the service and gets back a List of objects using AIDL. The service does work and updates a database.
If I leave the activity open for 4-8+ hours, and go to the "Running Services" section under settings on the phone (Nexus One) an unusually large amount of memory being used is shown (~42MB).
I figure there is a leak. When I check the heap memory i get Heap size:~18MB, ~2MB allocated, ~16MB free. Analyzing the hprof in Eclipse MAT seems fine, which leads me to theorize that memory is leaking on the stack. Is this even possible? If it is, what can I do to stop or investigate the leak? Is the reported memory usage on the "Running Services" section of android even correct (I assume it is)?
Another note: I have been unable to reproduce this issue when the UI is not up (with only the service running)
I'm writing an app that has a
foreground service, content provider,
and a Activity front end that binds to
the service and gets back a List of
objects using AIDL.
If that's all just one application, get rid of the AIDL and get rid of the content provider. Or, at least, don't use them yourself -- those are for other applications to use. They add overhead that you do not need for stuff inside your own VM.
...which leads me to theorize that memory is leaking on the stack. Is this even possible?
Not really. The main application thread stack is trivially small. Other threads have stacks that could get a lot bigger, but I'll be surprised if you are chewing up 42MB that way.
If it is, what can I do to stop or
investigate the leak?
Since you already did a "spike solution" of testing sans UI and determining that is OK, I'd slowly reintroduce the UI and see when you start getting the problem. One likely candidate problem area would be updating the activity from a background thread, so you might turn that off and see what happens.
Since your problem isn't in the heap itself, my guess is that your problem is tied to bitmaps or other things that have lots of off-heap RAM usage. The camera in your avatar is another hint in this direction. :-) Make sure you are recycle()-ing your bitmaps and such, and see if that helps any.
Related
I just try to understand the reason of it. Our app is really stable and optimized, but time to time it just switch off during the work on foreground mode. User is using it, and it' just closed without any crash or ANR messages - really bad experience. What we already did:
use UncaughtExceptionHandler and print logs to the disk for analyzing. Logs are empty, not information about crashes for these cases
used Firebase crashlityc - is empty too
checked app with help profiler and leakcanary - no leak, memory using ~200 Mb
A bit words about our app:
clear arhitecture, Kotlin, MVVM, coroutines, dagger, retrofit, room, one single activity app
app should work all time, infinitely. App is an interface for hardware terminal.
the most part of fragments are stored into the backstack and reused again, it help to make screen opening faster after first fragment using. No leak with it, no fragment or viewModels duplicates
we use glide for downloading and previewing user avatars. I'm afraid, that leaks could be a part of bitmaps or jpg. Profiler doesn't show it after 1-2 hours tests, but I didn't test it during for ex. one week
possible app interruptions happen more often, when device is uncharged or just started (first 10-20 minutes after device start)
the most part of clients has a bad WIFI connections
we have ~10 modules, the most part of them are own canvas libs
crashes happen in random moments...
we also have ANR problem for some clients, but we added ANR watchdog, so soon we will know the reason of it.
we have 50-60 singletons. I'm not sure, that is bad or good. The first plan was using much memory to make app faster.
For me it looks like a native crash or system kill, but how to repeat it? I still don't understand the real reason of it. If you faced with similar problem, please describe your experience, it could be helpful for us. Thx!
When running on Huawei G300 with Gingerbread, my app crashes after 5 minutes or so of usage during setContentView() as it runs out of memory.
Each individual page doesn't use much memory, but from some research it seems the memory accumulates in the back stack.
Following advice here, I've replaced all my calls to startActivity with a utility function that also calls finish().
Android: Clear the back stack
This works; but there is no more back stack - the back button immediately quits the app, which isn't what I wanted.
Is there a way to only finish() the applications when I actually do run out of memory, and is that a reasonable approach to take?
You should search for memory leaks. A good tool for that is MAT if you use eclipse. MAT is not that hard to handle and you can get quickly some very valuable information.
One of the most common mistakes I have seen on Android is to keep a reference on a context that is dead. For instance, having a singleton holding a reference on one of the activities you created. There is no real reason for an app to crash the memory if it is well coded.
The Android Activity Manager was designed to manage this exact problem. The OS is designed to kill activities in the background and then restore them using onSaveInstanceState and onRestoreInstanceState.
The fact that your app is accumulating memory usage over time indicates to me that you may have a Context leak somewhere (a static reference to a view, adapter, etc. that has a reference to a Context), or that you have a caching mechanism that's not adjusting to your memory heap, or some other situation that's causing the out of memory.
I highly doubt that it's the Activities in the Back Stack causing the Out of Memory.
Here's a great guide on tracking down memory leaks on Android:
http://android-developers.blogspot.com/2011/03/memory-analysis-for-android.html
Memory is a very tricky subject in Android.
Every app gets a heap memory limit depending on the device. This heap memory is the dalvik memory plus the native memory, and you can see it as the total column in the dumpsys meminfo results. The dalvik memory deals with everything except with the bitmaps, that are allocated in the native memory (this is true for Android versions before Honeycomb).
Having said that I can only answer to some of your questions:
As far as I know, Android will always allocate memory for Bitmaps, even if they are the same. Therefore, in your case, every activity allocates memory for your background.
I don't know if its better to work with themes, you'll have to try that.
On one hand, activities are not reclaimed while the device has enough memory to deal with the next activity. Every activity is pushed to a pile from where it is recovered when you pressed the back button. In case Android needs more memory it removes one activity from the pile deallocating its memory (going back to question number one, maybe this is the reason for not sharing memory). On the other hand, you can set the activities launchMode to change this behaviour (have a look here).
I think MAT doesn't show native memory data. Use dumpsys meminfo's native column to see how much allocated memory for Bitmaps you have.
I have had hard times dealing with OutOfMemory problems myself. Now I have a much more clear idea of how it works and I am able to work with large files without running out of memory. I would highly recommend these two resources that helped me a lot:
I have simple network counter application, which has two parts A service and a view.
I have a memory leak issue with my application. First I will explain my app briefly.
Service part
Service costs 2-3 Mb and in runs evertime. (starts with BOOT_COMPLETED and never die)
It sends statictics to server periodically. And I dont have a memory problem with Service.
Activity part
I have a, 1 layout very simple view that shows statictics to user.
If I dont add an Adview on it this view costs 3 Mb and no memory leak.
If I add a AdView on it, it costs 9 Mb(11Mb with Service) on memory and CONTINUE TO GROW on every pause/resume of activity. At the and I guess system kills whole application including service And this is very bad news.
I want to completely remove this Activity when not in use. (leaving Service alive.)
How can I completely remove Activity from memory apart from service?
I guess I should have some workaround in my case.
Notes:
I dont need orientation change. it is set to portrait.
btw, I really dont understand this is not fixed yet in Admob.
Here is some other resources I have tried.
Android Admob 4.1.1 has a memory leak (see attached test project). Cause/fix/work around?
Android AdMob causes memory leak?
http://1gravity.com/index.php?option=com_content&view=article&id=71:android-and-memory-leaks&catid=37:android&Itemid=59
I have an Android app with a running service.
When I look in the "Running Apps" menu in Android settings, I see that my app memory usage is
between 9-16MB .
I used DDMS Allocation Tracker to see where this is coming from, but all of the objects were less than 500 bytes.
Does it make sense? Any other ways to track my app's memory usage?
Also, I have an SQLite database opened as long as the service is running. Is that an impact on memory as well?
Thanks.
Does it make sense?
It neither makes sense nor doesn't make sense. You can get to "9-16MB" by increments of 500 as easily as you can get there by increments of 5000. Also, AFAIK that allocation tracker does not track everything (e.g., bitmaps on pre-3.0 environments).
Any other ways to track my app's memory usage?
Dump your heap (e.g., using the Dump HPROF File toolbar button in DDMS) and examine the results with the MAT plugin for Eclipse. There was a presentation on this at the 2011 Google I|O conference -- the YouTube video is online. You can use this to track memory leaks.
Is that an impact on memory as well?
Some, I'm sure.
Another issue is actually the service itself. Your objective should be to have that service in memory as little as possible, and only while it is actively delivering continuous value to the user. Ideally, your service is destroyed ~99% of the time.
I have an Android app that in the onCreate() method, preloads a lot of graphics.
When I test my app on my HTC Aria and launch it, it runs fine. However, if I press the back button to exit my app, and then launch the app again, it crashes with an OutOfMemoryError: bitmap size exceeds VM budget. If I then launch the app for the third time (right after it has crashed) it launches fine. Then if I close and re-launch it, it crashes again with out of memory. It continues this every-other-time-crashing pattern forever if I keep trying.
I checked to see what life cycle methods were being called and onStop() and onDestroy() are both being called when I exit the app, yet I have a feeling that something is not yet being cleaned up and that by "crashing" the app when I try to launch it the second time, it somehow free's the memory.
Any thoughts on what could be happening or how to remedy this? Please let me know if you need me to post more info. Thanks!
Info:
My app is fairly simple and only has 1 activity that plays some frame animations.
Maybe you are unnecessarily holding onto Context references? Check Avoiding memory leaks for some tips, as well as Attacking memory problems.
It sounds like something in the Activity life cycle is not quite right. Are you sure you have every start covered? http://developer.android.com/reference/android/app/Activity.html
You have onStop but do you have onDestroy? You're probably missing one of those that you need.
You may find some useful information the many answers to this question:
Strange out of memory issue while loading an image to a Bitmap object
Also, I second the "Avoiding Memory Leaks" blog post. Especially if you can trigger the same problem with orientation changes. Using "this" context when creating display objects is a sneaky way to leak the Activity context. In my own app, I managed to leak a whole chain of contexts, and would very rapidly run out of memory when doing orientation changes.