-c 100 即：每次并发100个
-n 10000 即： 共发送10000个请求


[root@wfoffice01 ~]$ ab -c 100 -n 10000 -p post.txt http://merchant.imt.com/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 merchant.imt.com (be patient)
Completed 1000 requests
Completed 2000 requests
Completed 3000 requests
Completed 4000 requests
Completed 5000 requests
Completed 6000 requests
Completed 7000 requests
Completed 8000 requests
Completed 9000 requests
Completed 10000 requests
Finished 10000 requests


Server Software:        openresty
Server Hostname:        merchant.imt.com
Server Port:            80

Document Path:          /index.php                                          // 请求的资源
Document Length:        1132 bytes                                          // 文档返回的长度，不包括相应头

Concurrency Level:      100                                                 // 并发个数
Time taken for tests:   65.924 seconds                                      // 总请求时间
Complete requests:      10000                                               // 总请求数
Failed requests:        0                                                   //失败的请求数
Write errors:           0
Total transferred:      15870000 bytes
Total POSTed:           1740000
HTML transferred:       11320000 bytes
Requests per second:    151.69 [#/sec] (mean)                               // 平均每秒的请求数
Time per request:       659.241 [ms] (mean)                                 // 平均每个请求消耗的时间
Time per request:       6.592 [ms] (mean, across all concurrent requests)   // 就是上面的时间 除以并发数
Transfer rate:          235.09 [Kbytes/sec] received                        // 时间传输速率
                        25.78 kb/s sent
                        260.86 kb/s total

Connection Times (ms)
              min  mean[+/-sd] median   max
Connect:        0    1  11.9      0     242
Processing:   242  658  81.6    651     990
Waiting:      242  658  81.6    651     990
Total:        262  658  81.3    652     990

Percentage of the requests served within a certain time (ms)
  50%    652    // 有50%的请求都是在652ms内完成的
  66%    681
  75%    703
  80%    717
  90%    766
  95%    813
  98%    854
  99%    873
 100%    990 (longest request)