Curl请求慢
背景原因:测试环境发现一个连接内网访问和外网访问延迟差别很大,内网访问很快。外网访问很慢。于是我们用curl来诊断问题所在的区域! 命令如下:
? 返回结果:
? ? ? ? ? -o:把curl 返回的html、js 写到垃圾回收站[ /dev/null] -s:去掉所有状态 -w:按照后面的格式写出rt time_namelookup:DNS 解析域名www.36nu.com的时间 time_commect:client和server端建立TCP 连接的时间 time_starttransfer:从client发出请求;到web的server 响应第一个字节的时间 time_total:client发出请求;到web的server发送会所有的相应数据的时间 speed_download:下周速度 单位 byte/s 上面这条命令及返回结果可以这么理解: 0.014: DNS 服务器解析www.36nu.com 的时间单位是s 0.015: client发出请求,到c/s 建立TCP 的时间;里面包括DNS解析的时间 0.018: client发出请求;到s响应发出第一个字节开始的时间;包括前面的2个时间 0.019: client发出请求;到s把响应的数据全部发送给client;并关闭connect的时间 1516256.00 :下载数据的速度 建立TCP连接到server返回client第一个字节的时间:0.018s – 0.015s = 0.003s server把响应数据发送给client的时间:0.019s – 0.018 = 0.01s ? #================================curl 其他参数详解============================ curl的部分时间等变量注释: url_effective The URL that was fetched last. This is most meaningful if you‘ve told curl to follow location: headers. filename_effective The ultimate filename that curl writes out to. This is only meaningful if curl is told to write to a file with the --remote-name or --output option. It‘s most useful in combination with the --remote-header-name option. (Added in 7.25.1) http_code http状态码,如200成功,301转向,404未找到,500服务器错误等。(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) time_total 总时间,按秒计。精确到小数点后三位。 (The total time,in seconds,that the full operation lasted. The time will be displayed with millisecond resolution.) time_namelookup DNS解析时间,从请求开始到DNS解析完毕所用时间。(The time,it took from the start until the name resolving was completed.) time_connect 连接时间,从开始到建立TCP连接完成所用时间,包括前边DNS解析时间,如果需要单纯的得到连接时间,用这个time_connect时间减去前边time_namelookup时间。以下同理,不再赘述。(The time,it took from the start until the TCP connect to the remote host (or proxy) was completed.) time_appconnect 连接建立完成时间,如SSL/SSH等建立连接或者完成三次握手时间。(The time,it took from the start until the SSL/SSH/etc connect/handshake to the remote host was completed. (Added in 7.19.0)) time_pretransfer 从开始到准备传输的时间。(The time,it took from the start until the file transfer was just about to begin. This includes all pre-transfer commands and negotiations that are specific to the particular protocol(s) involved.) time_redirect 重定向时间,包括到最后一次传输前的几次重定向的DNS解析,连接,预传输,传输时间。(The time,it took for all redirection steps include name lookup,connect,pretransfer and transfer before the final transaction was started. time_redirect shows the complete execution time for multiple redirections. (Added in 7.12.3)) time_starttransfer 开始传输时间。在client发出请求之后,Web 服务器返回数据的第一个字节所用的时间(The time,it took from the start until the first byte was just about to be transferred. This includes time_pretransfer and also the time the server needed to calculate the result.) size_download 下载大小。(The total amount of bytes that were downloaded.) size_upload 上传大小。(The total amount of bytes that were uploaded.) size_header 下载的header的大小(The total amount of bytes of the downloaded headers.) size_request 请求的大小。(The total amount of bytes that were sent in the HTTP request.) speed_download 下载速度,单位-字节每秒。(The average download speed that curl measured for the complete download. Bytes per second.) speed_upload 上传速度,单位-字节每秒。(The average upload speed that curl measured for the complete upload. Bytes per second.) content_type 就是content-Type,不用多说了,这是一个访问我博客首页返回的结果示例(text/html; charset=UTF-8);(The Content-Type of the requested document,if there was any.) 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) redirect_url When a HTTP request was made without -L to follow redirects,this variable will show the actual URL a redirect would take you to. (Added in 7.18.2) ftp_entry_path The initial path libcurl ended up in when logging on to the remote FTP server. (Added in 7.15.4) ssl_verify_result ssl认证结果,返回0表示认证成功。( The result of the SSL peer certificate verification that was requested. 0 means the verification was successful. (Added in 7.19.0))
输出变量需要按照%{variable_name}的格式,如果需要输出%,double一下即可,即%%,同时,n是换行,r是回车,t是TAB。? -w 指定格式化文件 -o 请求重定向到,不带此参数则控制台输出返回结果 -s 静默,不显示进度
1)以json格式数据 2)以&连接参数数据
其中-F 为带文件的形式发送post请求, ? blob为文本框中的name元素对应的属性值。<type="text" name="blob">
安卓手机可以通过安装终端模拟器,然后在模拟器按以上方法使用curl调试定位app在移动数据网络环境下哪个环节出现慢的问题。 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |