直接上图↓
图1
上面的命令，可以查看http请求各个环节的耗时情况，能够帮助我们排查和定位问题。
要实现上图的输出效果，需要将下面格式化文本提前准备好。
图2
有的朋友可能好奇，图1的命令为什么要加-o /dev/null？不加的话，会把响应也显示出来，看起来不够美观了~
那图1为啥还要加-s命令呢？如果不加的话，会显示下面的进度条信息↓
这个命令对于计算机网络学的好的同学来说，简直就是神器了，https://curl.haxx.se/docs/manpage.html这里面，搜索-w，可以看到完整的参数，大家可以根据需求，添加到curl-time.txt文本中~，下面截取部分内容，供大家参考。
http_code The numerical response code that was found in the last retrieved HTTP(S) or FTP(s) transfer. In 7.18.2 the alias response_code was added to show the same info.
http_connect The numerical code that was found in the last response (from a proxy) to a curl CONNECT request. (Added in 7.12.4)
http_version The http version that was effectively used. (Added in 7.50.0)
num_connects Number of new connects made in the recent transfer. (Added in 7.12.3)
num_redirects Number of redirects that were followed in the request. (Added in 7.12.3)
得到http请求各个环节的耗时情况，就可以定位瓶颈所在，展开进一步的排查和优化了~
预告一下，下篇文章将会给大家介绍下时序数据库openTSDB，敬请期待~
