这篇文章很水很水，但是很实用。
代码语言：javascript复制什么是QPS? QPS（Query Per Second）：每秒请求数，就是说服务器在一秒的时间内处理了多少个请求。
tomcat的accesslog的格式
119.250.238.218 - - [09/Oct/2019:03:32:46 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
当我们访问articleId=145这个文章的时候这个日志文件就会产生对应一条记录，那样我们就可以根据这个日志文件来统计1s内有几个访问，就可以知道对应得QPS
[root@iZwz9278r1bks3b80puk6fZ logs]# cat localhost_access_log.2019-10-09.txt | grep 'articleId=145'
119.250.238.218 - - [09/Oct/2019:03:32:46 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
27.202.249.24 - - [09/Oct/2019:03:34:04 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
115.210.28.171 - - [09/Oct/2019:03:35:24 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
115.209.119.49 - - [09/Oct/2019:03:36:42 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
123.131.123.179 - - [09/Oct/2019:03:38:02 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
144.123.71.235 - - [09/Oct/2019:03:39:21 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
175.4.114.136 - - [09/Oct/2019:03:40:42 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
115.209.125.149 - - [09/Oct/2019:03:42:02 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10959
112.194.70.154 - - [09/Oct/2019:03:43:23 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
36.33.54.7 - - [09/Oct/2019:03:44:40 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
115.148.70.51 - - [09/Oct/2019:03:45:57 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
183.188.243.35 - - [09/Oct/2019:03:47:14 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
113.73.169.139 - - [09/Oct/2019:03:48:33 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
49.71.139.184 - - [09/Oct/2019:03:49:51 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
113.239.250.255 - - [09/Oct/2019:03:51:00 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
180.123.169.120 - - [09/Oct/2019:03:52:09 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
223.72.96.183 - - [09/Oct/2019:03:53:28 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
180.118.234.162 - - [09/Oct/2019:03:54:46 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
175.44.156.161 - - [09/Oct/2019:03:56:05 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
223.72.100.175 - - [09/Oct/2019:03:57:21 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
218.85.247.86 - - [09/Oct/2019:03:58:38 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
220.186.84.151 - - [09/Oct/2019:03:59:59 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:08:56:58 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:08:59:15 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:09:04:07 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:09:07:28 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:09:07:29 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:09:09:31 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
117.30.53.211 - - [09/Oct/2019:09:09:31 0800] "GET /article/view.do?articleId=145 HTTP/1.1" 200 10960
[root@iZwz9278r1bks3b80puk6fZ logs]# cat localhost_access_log.2019-10-09.txt | grep 'articleId=145' |cut -d ' ' -f4|uniq -c|sort -n -r
2 [09/Oct/2019:09:09:31
1 [09/Oct/2019:09:07:29
1 [09/Oct/2019:09:07:28
1 [09/Oct/2019:09:04:07
......
这样就可以看出2019:09:09:31有两个访问量即可得 QPS=2
现在，来讲一下命令什么意思！
cat xxx.log:读文件内容
grep 'articleId=145':将文件内容按照GET /mvc2进行过滤
cut -d ' ' -f4:过滤出来的内容按照空格进行分割，取第四列内容
uniq -c:每列旁边显示该行重复出现的次数
sort -n -r:依照数值的大小排序 注意 上面的统计是单机版的，那假设我们的集群部署了4台机器，并且刚好是轮询的，这样乘4就行了。
