Php-timeit estimates the execution time of php functions, and php-timeitphp
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Sometimes, when optimizing PHP performance, we need to know the execution time of a function. In Python, there is a timeit module. in PHP, we do not know whether there are similar modules?
Therefore, I wrote a simple timeit function as follows:
/** * Compute the delay to execute a function a number of time * @param $count Number of time that the tests will execute the given function * @param $function the function to test. Can be a string with parameters (ex: 'myfunc(123, 0, 342)') or a callback * @return float Duration in seconds (as a float) */function timeit($count, $function) { if ($count <= 0){ echo "Error: count have to be more than zero"; return -1; } $nbargs = func_num_args(); if ($nbargs < 2) { echo 'Error: No Funciton!'; echo 'Usage:'; echo "\ttimeit(count, 'function(param)')"; echo "\te.g:timeit(100, 'function(0,2)')"; return -1; // no function to time } // Generate callback $func = func_get_arg(1); $func_name = current(explode('(', $func)); if (!function_exists($func_name)) { echo 'Error: Unknown Function'; return -1; // can't test unknown function } $str_cmd = ''; $str_cmd .= '$start = microtime(true);'; $str_cmd .= 'for($i=0; $i<'.$count.'; $i++) '.$func.';'; $str_cmd .= '$end = microtime(true);'; $str_cmd .= 'return ($end - $start);'; return eval($str_cmd);}
Test the execution time of a self-written root algorithm and built-in root function as follows:
// Take the square root function sqrt_nd ($ num) {$ value = $ num; while (abs ($ value * $ value-$ num)> 0.001) {$ value = ($ value + $ num/$ value)/2;} return $ value;} print timeit (1000, 'sqrt _ nd (5 )'); print "\ n"; print timeit (1000, 'sqrt (5 )');
The test results are as follows:
0.0282800197601320.0041000843048096
It can be seen that the built-in root function is more than six times faster than the custom root function ~~