用xdebug 分析系统瓶颈

http://xdebug.org/

下载xdebug

安装

1.linux

下载源码包http://xdebug.org/download.php

tar -zvxf xdebug.tgz

进入解压的目录

/usr/local/php/bin/phpize（可能你的系统会没有安装phpize,那就安装吧）

./configure --enable-xdebug

make

make install

修改配置文件

zend_extension = /usr/lib/php5/20090626/xdebug.so 
xdebug.profiler_enable = on  开启性能的监控
xdebug.auto_trace = on        开启函数的跟踪会在trace_output_dir目录下生成日志文件
xdebug.trace_output_dir = /var/tmp/xdebug
xdebug.trace_output_name = trace.%c
xdebug.profiler_output_dir = /var/tmp/xdebug

 php5.3之后不论是否是线程安全的都是用zend_extension,如果是之前的版本线程安全的版本用zend_extension_ts如果是非线程安全的zend_extensio

 trace_output_dir文件内容

TRACE START [2012-10-28 18:49:37]
    0.0001     629576   -> {main}() /var/www/myproject/load.php:0
    0.0002     634840     -> require(/var/www/myproject/view.php) /var/www/myproject/load.php:2
    0.0002     640064     -> require(/var/www/myproject/cache.php) /var/www/myproject/load.php:3
    0.0002     640440     -> CView->__construct() /var/www/myproject/load.php:42
    0.0002     640816       -> dirname() /var/www/myproject/view.php:16
    0.0003     640856     -> queryData() /var/www/myproject/load.php:43
    0.0004     641352       -> mysql_connect() /var/www/myproject/load.php:5
    0.0035     641632       -> mysql_query() /var/www/myproject/load.php:6
    0.0043     641624       -> mysql_select_db() /var/www/myproject/load.php:7
    0.0044     641640       -> mysql_query() /var/www/myproject/load.php:11
    0.0045     642296       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0045     644616       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0046     646936       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0047     649256       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0047     651576       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0047     653896       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0048     656216       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0048     658536       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0048     660856       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0048     663240       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0048     665560       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0049     667880       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0049     670200       -> mysql_fetch_array() /var/www/myproject/load.php:13
    0.0049     670200       -> mysql_close() /var/www/myproject/load.php:16
    0.0082     669296     -> CView->assign() /var/www/myproject/load.php:43
    0.0082     669376       -> is_array() /var/www/myproject/view.php:21
    0.0082     669376       -> is_array() /var/www/myproject/view.php:23
    0.0082     669376       -> is_null() /var/www/myproject/view.php:23
    0.0085     669736     -> CView->fetch() /var/www/myproject/load.php:44
    0.0086     669816       -> extract() /var/www/myproject/view.php:36
    0.0087     672120       -> ob_start() /var/www/myproject/view.php:37
    0.0087     714648       -> include(/var/www/myproject/view/users.php) /var/www/myproject/view.php:38
    0.0089     714872       -> ob_get_contents() /var/www/myproject/view.php:39
    0.0089     720504       -> ob_end_clean() /var/www/myproject/view.php:40
    0.0092      16744
TRACE END   [2012-10-28 18:49:37]

 第一列显示的是时间，黑体的记录是话费来比较多时间的代码，可以看出数据查询花来比较多。

profiler_output_dir文件的内容

 fl=php:internal
 78 fn=php::mysql_fetch_array
 79 13 2
 80 
 81 fl=php:internal
 82 fn=php::mysql_fetch_array
 83 13 1
 84 
 85 fl=php:internal
 86 fn=php::mysql_fetch_array
 87 13 1
 88 
 89 fl=php:internal
 90 fn=php::mysql_fetch_array
 91 13 1
 92 
 93 fl=php:internal
 94 fn=php::mysql_fetch_array
 95 13 0
 96 
 97 fl=php:internal
 98 fn=php::mysql_close
 99 16 1024
100 
101 fl=/var/www/myproject/load.php
102 fn=queryData
103 4 263
104 cfl=php:internal
105 cfn=php::mysql_connect
106 calls=1 0 0
107 5 2317
108 cfl=php:internal
109 cfn=php::mysql_query
110 calls=1 0 0
111 6 120
112 cfl=php:internal
113 cfn=php::mysql_select_db

这个文件可以通过工具kcachegrind来分析

 我们可以看到数据库操作话费的时间最多占据来87.81ms,其中又一链接数据库话费的最多41.62ms

还可以以百分比的方式查看。