I discovered a great debugging tool today from the article Flags: very useful when debugging with Instruments The article talks about how to put up flags from your code that appear in the Instruments window. This is a feature that is new to Instruments 4.0 and is described in the Apple docs at New Features in Instruments 4.0 Let’s jump to the end and show you an example of what you can put up in your Instruments display:
Note the yellow flags above the trace. These were generated in my code within a loop. If you click on a flag you can see the text that I generated for the flag “Loop index 38” along with the source file, line number of the code generating the flag and the method being executed.