Apache自帶的性能測試工具ab的使用
小弟在學校負責一個測試團隊，為學校的項目做測試，其間有些膚淺的作品，還請各位前輩多多指導^__^
1 概述
ab（ApacheBench）是Apache自帶的超文本傳輸協議(HTTP)性能測試工具。 其設計意圖是描繪當前所安裝的Apache的執行性能， 主要是顯示你安裝的Apache每秒可以處理多少個請求。
2 使用
2.1 安裝
Apache服務器套件自帶ab，只要安裝Apache即可，無需另行安裝ab。ab位于%ApacheHome%/bin目錄下（“%ApacheHome%”為Aapche安裝路徑），你也可以把ab.exe文件copy出來，獨立使用。
2.2 參數列表
C:>ab
ab: wrong number of arguments
Usage: ab [options] [http://]hostname[:port]/path
Options are:
-n requests Number of requests to perform
-c concurrency Number of multiple requests to make
-t timelimit Seconds to max. wait for responses
-p postfile File containing data to POST
-T content-type Content-type header for POSTing
-v verbosity How much troubleshooting info to print
-w Print out results in HTML tables
-i Use HEAD instead of GET
-x attributes String to insert as table attributes
-y attributes String to insert as tr attributes
-z attributes String to insert as td or th attributes
-C attribute Add cookie， eg. 'Apache=1234. (repeatable)
-H attribute Add Arbitrary header line， eg. 'Aclearcase/" target="_blank" >ccept-Encoding: gzip'
Inserted after all normal header lines. (repeatable)
-A attribute Add Basic WWW Authentication， the attributes
are a colon separated username and password.
-P attribute Add Basic Proxy Authentication， the attributes
are a colon separated username and password.
-X proxy:port Proxyserver and port number to use
-V Print version number and exit
-k Use HTTP KeepAlive feature
-d Do not show percentiles served table.
-S Do not show confidence estimators and warnings.
-g filename Output collected data to gnuplot format file.
-e filename Output CSV file with percentages served
-h Display usage information (this message)
* 中文的列表可以查看Apache手冊中文版。
以上參數常用的是-n 在測試會話中所執行的請求個數；和-c 一次同時產生的并發請求個數。
2.3 實例
假設我們要測試一個PHP論壇系統，其中一個性能測試用例是：“同時處理50個并發請求并運行 1000 次index.php 首頁”，我們可以在cmd shell中輸入 ab -n 1000 -c 50 http://172.16.11.180:88/bbs/index.php，運行結束后，ab會自動顯示測試結果，如下：
E:WebserApache2in>ab -n 1000 -c 50 http://172.16.11.180:88/bbs/index.php
This is ApacheBench， Version 2.0.41-dev <$Revision: 1.121.2.12 $> apache-2.0
Copyright (c) 1996 Adam Twiss， Zeus Technology Ltd， http://www.zeustech.net/
Copyright (c) 1998-2002 The Apache Software Foundation， http://www.apache.org/
Benchmarking 172.16.11.180 (be patient)
Completed 100 requests
Completed 200 requests
Completed 300 requests
Completed 400 requests
Completed 500 requests
Completed 600 requests
Completed 700 requests
Completed 800 requests
Completed 900 requests
Finished 1000 requests
Server Software: Apache
Server Hostname: 172.16.11.180
Server Port: 88
Document Path: /bbs/index.php
Document Length: 36962 bytes
Concurrency Level: 50
Time taken for tests: 262.515625 seconds
Complete requests: 1000
Failed requests: 198
(Connect: 0， Length: 198， Exceptions: 0)
Write errors: 0
Total transferred: 37408432 bytes
HTML transferred: 36967364 bytes
Requests per second: 3.81 [#/sec] (mean)
Time per request: 13125.781 [ms] (mean)
Time per request: 262.516 [ms] (mean， across all concurrent requests)
Transfer rate: 139.16 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 1 4.5 0 15
Processing: 297 12818 2427.6 12921 30578
Waiting: 281 12801 2427.6 12906 30562
Total: 312 12820 2427.5 12921 30578
Percentage of the requests served within a certain time (ms)
50% 12921
66% 13203
75% 13453
80% 13546
90% 13781
95% 14156
98% 14750
99% 18328
30578 (longest request)
以上結果指出，在并發50個請求的情況下，完成1000次的訪問請求，共花了262.515秒，這個程序每秒可處理3.81個請求。
2.4 問題
在實際使用中，我發現-c 參數，即一次同時產生的并發請求個數多設置成64，大于等于65會報錯，不知道為什么。
3 資料
ab官方網站：http://httpd.apache.org/docs/2.0/programs/ab.html
Apache 2.0手冊中文版翻譯項目ab部分：https://support.iap.ac.cn/net/ApacheManual/zh-cn/programs/ab.html
