Let us say i've two functions in functions.php in Wordpress.

  // it takes 2 minutes to finish whatever it does
  // it takes 3 minutes to finish whatever it does

My real question is how would be the functions performed?

1.First is performed function1 so when it's finished begins the execution of function2, therefore the final time is going to be a few minutes?

2.The execution for begins in the same time frame and also the final time is going to be 3 minutes?

Hope you'll understang my problem, thanks.

a few minutes - PHP will run the functions one by one, instead of the kind of JS which will run them at the same time.

I'd question what takes 2-3 minutes to process in PHP though? Most browsers will break after thirty seconds of PHP execution, so a few minutes could be method to lengthy...

so far as I understand function2 begins after function1 has finished performing... therefore the total execution time is a few minutes inside your situation...