问题
I'm looking for a way to find out how much time is spent in each of my program's source line when running on the iPhone.Similar to what Shark can provide on the method/function level. Is this possible with the standard tools? Are there 3rd party tools that can provide this sort of granularity?
It wouldn't be necessary for profiling data for every line of source code in the project to be collected. Ideally one would be able to select specific methods or functions whose performance would be analyzed.
回答1:
This link talks about how to gather trace data on an iPhone app, and that includes sampling the stack. Unfortunately, I could not tell from the doc if you can have samples drawn at random wall-clock times, or manually when you hit a key combination.
When you have traces, you can get a call tree, and that should get you line-level information. In fact the percent of time a line is responsible for is a simple number, the fraction of stack traces containing the line. The problem is, the UI may not show you that. The fact that that is a useful statistic is not well known.
来源：https://stackoverflow.com/questions/2052598/line-level-profiling-for-iphone