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Help w/ memory management...allocations shows no leaks but program leaks like crazy

So I have autoreleased/released开发者_开发知识库 every object that I alloc/init/copy...and the allocations instrument seems to show minimal leaks...however...my program's memory usage does not stop increasing. I have included a screenshot of my allocations run (I have run allocations for longer but it remains relatively constant...it certainly does not compare to the amount the program gains when actually running. When running my program it will double in memory over the course of about 10 hours. The memory drastically increases in the first 5 minutes however (2-3MB), and just keeps on going. I don't understand why allocations would remain constant when running in instruments but my program would just keep gaining memory when actually run.

Since I can't post images yet...here is the link to the screenshot:

allocations run

UPDATE: Here are some screenshots from my memory heapshot analysis...I am not allocating these objects explicitly and don't really know where they are coming from. Almost all of them have their source with something similar to the second screenshot details on the right (lots of HTTPs and URLs in the call tree). Anybody know where these are coming from? I know I've read about some NSURLConnection leaks but I have tried all of the cache clearing that those suggest to no avail. Thanks for all the help so far!

memory heap analysis 1

memory heap analysis 2


Try heapshots.


Are you running with different environment variables when you run in different environments? For example, you could have NSZombie enabled when you launch your app (causing all your objects to not be free'd) but not when you run in Instruments?

Just for a sanity check - How are you determining memory usage? You say that memory usage keeps going up, but not when you run in Instruments. Given that Instruments is a reliable way of measuring memory usage (the most reliable way?) this sounds a little odd - a bit like saying memory keeps going up except when i try to measure it.


If you are using autoreleased objects (like [NSString stringWithFormat:]) in a loop the pool won't be drained until that loop is exited and the program is allowed to complete the main event loop, at which point the autorelease pool is drained and a new one is instantiated.

If you have code like this the solution is to instantiate a new auto release pool before entering your loop, then draining it periodically during your loop (and reinstantiating the auto release pool after you drain it).


You can use Instruments to find out the location of where your allocations are originating. When running Instruments in the Allocation mode:

  • Move your mouse over the Category field in the Object Summary
  • Click on the Grey Circle with an arrow which appears next to the field name

This will bring up a list of locations where the objects in that category have been instantiated from, and the stats of how many allocations each have made.

If your memory usage is rising (but not leaking) you should be able to see where that memory was created, and then track down why it is hanging around.

This tool is also very useful in reducing your memory profile for mobile applications.

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