date - PHP get exact time a particular line is executed -

I'm trying to do simple benchmark on a script that I have first of all I tried to do something like this:

  'After the checklist': Date ('H: I: S: U A'). "& Lt; br / & gt;";   
 But it prints for a very long time - unless the script is included, it does not happen that it gives a different time. Is there any way of doing it? Or something similar - I basically want to see how much the obstacles are, so I can increase the performance.   
 
 
, which will return the current Unix timestamp with Microsoft.  
 From here you can simplify to start and end time to get desired results. Although the move is in the function to pass in "true", so it returns a float value instead of string.  
 For example, as posted on php.net: