WordPress Version: 6.3
/**
* Starts the WordPress micro-timer.
*
* @since 0.71
* @access private
*
* @global float $timestart Unix timestamp set at the beginning of the page load.
* @see timer_stop()
*
* @return bool Always returns true.
*/
function timer_start()
{
global $timestart;
$timestart = microtime(true);
return true;
}