I have spent few days working on this issue. That my app is getting crashed in iPod Touch due to Memory leak.
I have monitored heap growth exactly by Instrument in Xcode and it is confirmed that code is making memory occupied by app grow on each event.
I need to mention here that I am using ARC and hence i was really not expecting app to crash because of memory issue, although ARC isn't helpful incase Core foundation is used but I haven't used Core foundation in my app directly.
But MBProgressHUD is added in my app which uses this framework. I have not enabled ARC for MBProgressHUD as it was causing lot of memory grow.
I still am unable to track the main problem/variable/code which is causing my app memory to grow so much and causing app to crash.
P.S : Instrument had shown few functions causing lot of memory allocation but in those functions also I don't know how to free those variables as ARC is enabled (It is managed automatically).
Please suggest if I am in right direction.
Is it leaking or allocation is more? main cause for the app slow down is using too many number of autorelease objects.
Related
I am having trouble understanding the leaks found by the Leaks instrument right after build. Is this being caused by my own code or a library?
Let me know if you need more information, and thanks!
libSystem.dylib is a system library. If you run your app on a device you shouldn't encounter this leak anymore.
The leak is related to the way the simulator works.
looks like it some system code and it's probably allocating a permanent memory chunk. It's a very small allocation and there's only two of them. I don't think its a concern--all apps "leak" some memory.
what to watch out for:
many repeated small allocations... For example: an NSString created and leaked every time you adjust a volume slider.
larger chunks that are meant to be used once and thrown away. For example, an image loaded for a window background that isn't released when the window is closed
So I just made an app that loads a map with some markers on it. The app has a navigation controller that segue from the main screen to the map and back. While running the app on my phone and simulator i noticed that if i went back and forth between the home screen and the map, the amount of memory that the app was using just kept growing indefinitely. Is there way to assist in the process of memory management (i know the system uses ARC)? Im using the google maps sdk btw.
Thanks!
Does it cause the app to run out of memory and crash?
Or is it using a ton of memory, receiving a memory warning, and dumping said memory?
So, unless it is causing crashes, it may be behaving correctly.
Apple has extensive and well-documented support for diagnosing these kinds of problems. See "Locating Memory Issues in Your App".
Check your codes where using NSThreads and GCD blocks. If there are some places you create plenty of threads, it is recommended to add a autoreleasepool block.
Memory may leak in these situation:
If you are writing a program that is not based on a UI framework, such as a command-line tool.
If you write a loop that creates many temporary objects.
If you spawn a secondary thread.
For reference: Using Autorelease Pool Blocks
I am developing an app that is crashing due to an excess of memory usage. I would like to know the amount of memory that is being used by each active thread so that I can decide which allocated or drawn in screen elements release or remove from view. Is there a way to obtain it?
I have tried using mach.h library but with mach_task_self() I can only access the memory used by the whole application.
Thanks in advance
I think what you want is logMemUsage().
You can check the Answer from this Question :
Watching memory usage in iOS
I think you can get something from this Documentation also :
Understanding and Analyzing iOS Application Crash Reports
If you want to check Memory Usage While Application is Running then use Instruments. :
Using Instruments you can check how much memory your app is using. In Xcode4, use 'Profile' build, choose Leaks, then click the Library button in the toolbar and add the Memory Monitor instrument.
If you really don't want to use Instruments then you can use Custom Class UIDeviceAdditions :
Get current Memory usage
Hope it's Enough.
You can't because threads share the heap. Threads are created with a 512KB stack space, with memory pages allocated as needed. Other than that, there is no memory per thread value stored anywhere.
How can I make sure that reason of crashes is lack of memory?
Is there anything specific in crash log?
Maybe I have to use some tools or libraries?
UPDATE: my app uses lot of memory and receives memory warnings. It's very difficult to reduce memory usage. It crashes because of memory warnings time to time. But I want to make sure that it doesn't crash because of other reasons.
So how can I check the reason of app crash (it receives lots of memory warnings every time)
UPDATE2: Application has lots of 3D graphics and complex UI that takes lots of memory for textures. Customer doesn't want to make any kind of "loading..." pauses. If I unload invisible textures in background I can't get smooth animations.
So I just need to detect is there any crash reasons except memory.
At least you could implement the method
- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application
in your app delegate, and put a log to see if this indeed you are going through it before crashing.
Product -> Profile -> leak is a possible method to check memory leak. Allocations will show the total memory being used, and leaks will show leaks due to not releasing.
how-to-debug-memory-leaks-with-xcode-and-instruments-tutorial
that is a useful tutorial
You can use Apple's Instruments Tool to profile various things such as memory usage. This tool is bundled together with Xcode.
I’m helping out a company with a project for iOS, which is using Core Text. Some users of the app have reported that text is occasionally missing from within the app. It seems™ that this is somewhat memory related, because it’s solvable by shutting down the app along with background apps.
I made a few lines of code which simulates the use of the app – so the app “runs itself”, navigating between view controllers randomly, scrolling in text fields etc – to track if this issue occurs by normal use.
I’ve found some memory leaks related to the use of Core Text, but according to instruments the amount of memory lost is quite low. However, when the simulation has been running for about 20 minutes or so, the app is shut down by the os because of memory warnings.
I’m intending to fix this memory leaks, but my problem is that I will not be able to ensure that this fixes the main bug (missing text), since I cannot reproduce it myself.
So my final question is: have anyone experienced issues with missing text on iOS while using Core Text, which are due to leaked memory? Does it sound plausible? If so, is this related to only specific versions of iOS?
I appreciate any answers that can help me out!
UIViewControllers may implement didReceiveMemoryWarning that the system calls when your app is on low memory. Framework classes, as core text, are most likely do implement this and act accordingly to save memory. So it is possible that your core text object aims to help your app resolving the low-mem situation with freeing some of its resources that can even cause it to blank its contents. Fix first all memory leaks in your app.
On the other hand, all bugs are very difficult to correct if you can't reproduce them. If you suspect that the issue is due to low memory, try to simulate this yourself by allocating huge amount of memory in your application and hope that you can reproduce the erroneous behavior that way.