Question

I’ve seen Q/A here about timing function duration in other languages but didn’t find anything in Objective-C. If there is one, post the link and I will delete this question

I want to measure the time it takes for some functions to run. I’ve cobbled together the bits of code below but I wonder if there is a more compact or portable way to do this.

 CFTimeInterval startTime = CFAbsoluteTimeGetCurrent();

 // do some work

 CFTimeInterval difference = CFAbsoluteTimeGetCurrent() - startTime;

 printf("elapsed:  %f\n", difference)

Answer 1

If you want to precisely time very short timespans there are two additional timing facilities with very low overhead that come to my mind:

• mach_absolute_time with nanosecond resolution
• __builtin_readcyclecounter: a clang builtin function to read a low-latency, high-accuracy clock.