AB test

1. 在 Apache 套件工具有個叫 ab(ApacheBench) 的程式，專門用在做壓力測試。安裝套件 httpd-tools。

   [root@e517nat ~]# yum install httpd-tools
   

2. 在 moodle.cyut.edu.tw 本機直接進行壓力測試，同時 1000 個連線做 20 次，測試結果前 50% 完成連線需要 1722ms， 100% 完成連線需要 2141ms。

   [root@moodle ~]#  ab -n 1000 -c 20 http://moodle.cyut.edu.tw/index.php
   This is ApacheBench, Version 2.3 <$Revision: 655654 $>
   Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
   Licensed to The Apache Software Foundation, http://www.apache.org/
   
   Benchmarking moodle.cyut.edu.tw (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
   Completed 1000 requests
   Finished 1000 requests
   
   
   Server Software:        Apache/2.2.15
   Server Hostname:        moodle.cyut.edu.tw
   Server Port:            80
   
   Document Path:          /index.php
   Document Length:        38781 bytes
   
   Concurrency Level:      20
   Time taken for tests:   86.830 seconds
   Complete requests:      1000
   Failed requests:        0
   Write errors:           0
   Total transferred:      39357000 bytes
   HTML transferred:       38781000 bytes
   Requests per second:    11.52 [#/sec] (mean)
   Time per request:       1736.599 [ms] (mean)
   Time per request:       86.830 [ms] (mean, across all concurrent requests)
   Transfer rate:          442.64 [Kbytes/sec] received
   
   Connection Times (ms)
                 min  mean[+/-sd] median   max
   Connect:        0    1   5.5      0      62
   Processing:   896 1730 109.4   1722    2141
   Waiting:      775 1236  77.5   1230    1615
   Total:        897 1730 110.5   1722    2141
   
   Percentage of the requests served within a certain time (ms)
     50%   1722
     66%   1758
     75%   1782
     80%   1800
     90%   1855
     95%   1905
     98%   1982
     99%   2025
    100%   2141 (longest request)
   

3. 從外部主機 dyw219 進行壓力測試，同時 1000 個連線做 20 次，只能同時 229 個連線，無法完成同時 1000 個連線的測試。經查詢路由中為防止 DoS 攻擊，限制同一 ip 同時間最多只能 200 sessions。

   [root@dyw219 nat]# ab -n 1000 -c 20 http://moodle.cyut.edu.tw/index.php
   This is ApacheBench, Version 2.3 <$Revision: 655654 $>
   Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
   Licensed to The Apache Software Foundation, http://www.apache.org/
   
   Benchmarking moodle.cyut.edu.tw (be patient)
   Completed 100 requests
   Completed 200 requests
   apr_poll: The timeout specified has expired (70007)
   Total of 229 requests completed
   

4. 經放行主機 e517nat 後進行壓力測試，同時 1000 個連線做 20 次，測試結果前 50% 完成連線需要 1742ms， 100% 完成連線需要 2182ms。

   [root@e517nat ~]# ab -n 1000 -c 20 http://moodle.cyut.edu.tw/index.php
   This is ApacheBench, Version 2.3 <$Revision: 655654 $>
   Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
   Licensed to The Apache Software Foundation, http://www.apache.org/
   
   Benchmarking moodle.cyut.edu.tw (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
   Completed 1000 requests
   Finished 1000 requests
   
   
   Server Software:        Apache/2.2.15
   Server Hostname:        moodle.cyut.edu.tw
   Server Port:            80
   
   Document Path:          /index.php
   Document Length:        38781 bytes
   
   Concurrency Level:      20
   Time taken for tests:   87.383 seconds
   Complete requests:      1000
   Failed requests:        0
   Write errors:           0
   Total transferred:      39357000 bytes
   HTML transferred:       38781000 bytes
   Requests per second:    11.44 [#/sec] (mean)
   Time per request:       1747.652 [ms] (mean)
   Time per request:       87.383 [ms] (mean, across all concurrent requests)
   Transfer rate:          439.84 [Kbytes/sec] received
   
   Connection Times (ms)
                 min  mean[+/-sd] median   max
   Connect:        0    1   1.0      1      30
   Processing:   921 1740 145.2   1741    2181
   Waiting:      371 1248 105.8   1249    1588
   Total:        922 1740 145.2   1742    2182
   
   Percentage of the requests served within a certain time (ms)
     50%   1742
     66%   1800
     75%   1833
     80%   1853
     90%   1913
     95%   1965
     98%   2024
     99%   2071
    100%   2182 (longest request)