如何知道函数消耗了多少cpu时间和其他资源？ [重复]

Question

This question already has an answer here:

• How to track php functions/codes duration of processing 3 answers
• Tool to profile php code 4 answers

Don't need accurate, just approximately. Then I can know the performance of this function.

</div>

Answer 1

Don't need accurate, just approximately.

You could use memory_get_usage(). Otherwise profile with microtime().

Then I can know the performance of this function.

Relative to what?

What sort of thing are you trying to measure? Donald Knuth once said something about optimisation...