search
Homephp教程php手册CI框架源码阅读---------基准测试类Benchmark.php

 [php]  

/** 

 * CodeIgniter 

 * 

 * An open source application development framework for PHP 5.1.6 or newer 

 * 

 * @package     CodeIgniter 

 * @author      ExpressionEngine Dev Team 

 * @copyright   Copyright (c) 2008 - 2011, EllisLab, Inc. 

 * @license     http://codeigniter.com/user_guide/license.html 

 * @link        http://codeigniter.com 

 * @since       Version 1.0 

 * @filesource 

 */  

  

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

  

/** 

 * CodeIgniter Benchmark Class 

 * 

 * This class enables 能够 you to mark points and calculate 计算 the time difference 差异 

 * between them.  Memory consumption can also be displayed. 

 * 

 * @package     CodeIgniter 

 * @subpackage  Libraries 

 * @category    Libraries 

 * @author      ExpressionEngine Dev Team 

 * @link        http://codeigniter.com/user_guide/libraries/benchmark.html 

 */  

class CI_Benchmark {  

  

    /** 

     * List of all benchmark markers and when they were added 

     * 用来存储基准测试类标记的数组 

     * @var array 

     */  

    var $marker = array();  

  

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

  

    /** 

     * Set a benchmark marker 

     * 设置一个标记点 

     * 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)  

    {  

        // 在程序的任意地方调用方法时,会记录当前的时间点。  

        $this->marker[$name] = microtime();  

    }  

  

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

  

    /** 

     * Calculates the time difference between two marked points. 

     * 计算出两个时间点之间的时间。 

     * If the first parameter is empty this function instead returns the 

     * {elapsed_time} pseudo-variable 虚假变量. This permits 许可 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)  

    {  

        /*  

         * 如果没有给出明确的时间点,那么会计算出整个程序运行的时间。 

         * 怎么可以做到计算出整个程序的运行时间的呢?其实执行此计算的是Output组件。 

         * 而调用Benchmark::elapsed_time();(无参数)的时候,实质上先返回的并不是 

         * 整个程序运行的时间,也不可能做到,实质返回的是一个{elapsed_time}标签,然后 

         * Output在处理输出的时候,再计算出整个程序运行时间,因为处理输出阶段程序可以视 

         * 为处于最后阶段,于是可以近似计算出总时间,然后把输出中的{elapsed_time}替换掉。 

         * 下面的memory_usage()原理相同。 

         */  

        if ($point1 == '')  

        {  

            return '{elapsed_time}';  

        }  

  

        if ( ! isset($this->marker[$point1]))  

        {  

            return '';  

        }  

  

        if ( ! isset($this->marker[$point2]))  

        {  

            $this->marker[$point2] = microtime();  

        }  

  

        //这里为什么要用到list,是因为microtime();返回值是“msec sec”的格式。  

        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. 

     * www.2cto.com

     * @access  public 

     * @return  string 

     */  

    function memory_usage()  

    {  

        return '{memory_usage}';  

    }  

  

}  

  

// END CI_Benchmark class  

  

/* End of file Benchmark.php */  

/* Location: ./system/core/Benchmark.php */  

 

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Atom editor mac version download

Atom editor mac version download

The most popular open source editor

SublimeText3 English version

SublimeText3 English version

Recommended: Win version, supports code prompts!

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

DVWA

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

MinGW - Minimalist GNU for Windows

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.