また後できちんと書きます。 <?php function microtime_float() { list($usec, $sec) = explode(' ', microtime()); return ((float)$sec + (float)$usec); } $time1_start = microtime_float(); for ($i = 0; $i < 10000000; ++$i) { $time = time(); } $time1_end = microtime_float(); $time2_start = microtime_float(); for ($i = 0; $i < 10000000; ++$i) { $time = $_SERVER['REQUEST_TIME']; } $time2_end = microtime_float(); define(