How do you profile your code?

Question

I hope not everyone is using Rational Purify.

So what do you do when you want to measure:

• time taken by a function
• peak memory usage

Answer 1

If you're doing an 'on the metal' embedded 'C' system (I'm not quite sure what 'mobile' implied in your posting), then you usually have some kind of timer ISR, in which it's fairly easy to sample the code address at which the interrupt occurred (by digging back in the stack or looking at link registers or whatever). Then it's trivial to build a histogram of addresses at some combination of granularity/range-of-interest.

It's usually then not too hard to concoct some combination of code/script/Excel sheets which merges your histogram counts with addresses from your linker symbol/list file to give you profile information.

If you're very RAM limited, it can be a bit of a pain to collect enough data for this to be both simple and useful, but you would need to tell us a more about your platform.