system/libraries/Benchmark.php

<?php  if (!defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2006, EllisLab, Inc.
 * @license		http://www.codeigniter.com/user_guide/license.html
 * @link		http://www.codeigniter.com
 * @since		Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * CodeIgniter Benchmark Class
 *
 * This class enables you to mark points and calculate the time difference
 * between them.  Memory consumption can also be displayed.
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Libraries
 * @author		ExpressionEngine Dev Team
 * @link		http://www.codeigniter.com/user_guide/libraries/benchmark.html
 */
class CI_Benchmark {

	var $marker = array();

	// --------------------------------------------------------------------

	/**
	 * Set a benchmark marker
	 *
	 * Multiple calls to this function can be made so that several
	 * execution points can be timed
	 *
	 * @access	public
	 * @param	string	$name	name of the marker
	 * @return	void
	 */
	function mark($name)
	{
		$this->marker[$name] = microtime();
	}
  	
	// --------------------------------------------------------------------

	/**
	 * Calculates the time difference between two marked points.
	 *
	 * If the first parameter is empty this function instead returns the
	 * {elapsed_time} pseudo-variable. This permits the full system
	 * execution time to be shown in a template. The output class will
	 * swap the real value for this variable.
	 *
	 * @access	public
	 * @param	string	a particular marked point
	 * @param	string	a particular marked point
	 * @param	integer	the number of decimal places
	 * @return	mixed
	 */
	function elapsed_time($point1 = '', $point2 = '', $decimals = 4)
	{
		if ($point1 == '')
		{
			return '{elapsed_time}';
		}
		
		if ( ! isset($this->marker[$point1]))
		{
			return '';
		}
		
		if ( ! isset($this->marker[$point2]))
		{
			$this->marker[$point2] = microtime();
		}
			
		list($sm, $ss) = explode(' ', $this->marker[$point1]);
		list($em, $es) = explode(' ', $this->marker[$point2]);

		return number_format(($em + $es) - ($sm + $ss), $decimals);
	}
 	
	// --------------------------------------------------------------------

	/**
	 * Memory Usage
	 *
	 * This function returns the {memory_usage} pseudo-variable.
	 * This permits it to be put it anywhere in a template
	 * without the memory being calculated until the end.
	 * The output class will swap the real value for this variable.
	 *
	 * @access	public
	 * @return	string
	 */
	function memory_usage()
	{
		return '{memory_usage}';
	}

}

// END CI_Benchmark class
?>