直接上圖↓
圖1
上面的命令，可以查看http請求各個環節的耗時情況，能夠幫助我們排查和定位問題。
要實現上圖的輸出效果，需要將下面格式化文本提前準備好。
圖2
有的朋友可能好奇，圖1的命令爲什麼要加-o /dev/null？不加的話，會把響應也顯示出來，看起來不夠美觀了~
那圖1爲啥還要加-s命令呢？如果不加的話，會顯示下面的進度條信息↓
這個命令對於計算機網絡學的好的同學來說，簡直就是神器了，https://curl.haxx.se/docs/manpage.html這裏面，搜索-w，可以看到完整的參數，大家可以根據需求，添加到curl-time.txt文本中~，下面截取部分內容，供大家參考。
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請求各個環節的耗時情況，就可以定位瓶頸所在，展開進一步的排查和優化了~
預告一下，下篇文章將會給大家介紹下時序數據庫openTSDB，敬請期待~
最後祝各位老鐵，小年快樂！