文件说明

ab是apache自带的一个很好用的压力测试工具，当安装完apache的时候，就可以在bin下面找到ab

下载链接：

Linux/Mac：http://httpd.apache.org/download.cgi#apache24
Windows：http://www.apachehaus.com/cgi-bin/download.plx
下载后解压，并追加PATH环境变量，如";E:\software\Apache24\bin"

测试用例

#我们可以模拟100个并发用户，对一个页面发送100个请求#
ab -n 100 -c 100 -p E:\param.txt -T application/json http://xx.com
-n 请求数
-c 并发数
-p 参数文本路径
-T 请求参数类型

返回信息解析

This is ApacheBench, Version 2.3 <$Revision: 1796539 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/

Benchmarking 127.0.0.1 (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-Coyote/1.1    ##apache版本 
Server Hostname:        127.0.0.1   ##请求的机子 
Server Port:            8080 ##请求端口


Document Path:          /
Document Length:        1825 bytes  ##页面长度


Concurrency Level:      100  ##并发数 
Time taken for tests:   0.273 seconds  ##共使用了多少时间 
Complete requests:      1000   ##请求数 
Failed requests:        0   ##失败请求 
Total transferred:      275000 bytes  ##总共传输字节数，包含http的头信息等 
HTML transferred:       25000 bytes  ##html字节数，实际的页面传递字节数 
Requests per second:    3661.60 [#/sec] (mean)  ##每秒多少请求，这个是非常重要的参数数值，服务器的吞吐量 
Time per request:       27.310 [ms] (mean)  ##用户平均请求等待时间 
Time per request:       0.273 [ms] (mean, across all concurrent requests)  #服务器平均处理时间
Transfer rate:          983.34 [Kbytes/sec] received  ##每秒获取的数据长度


Connection Times (ms) 
              min  mean[+/-sd] median   max 
Connect:        0    1   2.3      0      16 
Processing:     6   25   3.2     25      32 
Waiting:        5   24   3.2     25      32 
Total:          6   25   4.0     25      48


Percentage of the requests served within a certain time (ms) 
  50%     25  ## 50%的请求在25ms内返回 
  66%     26  ## 60%的请求在26ms内返回 
  75%     26 
  80%     26 
  90%     27 
  95%     31 
  98%     38 
  99%     43 
100%     48 (longest request)