Finding Leaks Using Instruments
The Instruments application can be used to find leaks in both OS X and iPhone applications. To find leaks, create a new document template in Instruments and add the Leaks instrument to it. The Leaks instrument provides leak-detection capabilities identical to those in the leaks command-line tool. The Leaks instrument records all allocation events that occur in your application and then periodically searches the application’s writable memory, registers, and stack for references to any active memory blocks. If it does not find a reference to a block in one of these places, it deems the block a “leak” and displays the relevant information in the Detail pane.
In the Detail pane, you can view leaked memory blocks using Table and Outline modes. In Table mode, Instruments displays the complete list of leaked blocks, sorted by size. Selecting an entry in the table and clicking the arrow button next to the memory address shows the allocation history for the memory block at that address. Selecting an entry from this allocation history then shows the stack trace for that event in the Extended Detail pane of the document window. In Outline mode, the Leaks instrument displays leaks organized by call tree, which you can use to get information about the leaks in a particular branch of your code.
For more information about using the Instruments application, including more information about the information displayed by the Leaks instrument, see
Instruments User Guide.
