用Wireshark抓包分析超过70秒的请求

超过70秒的请求是通过分析IIS日志发现的：

10.159.63.104是SLB的内网IP。

通过Wireshark抓包分析请求是9:22:21收到的(tcp.stream eq 23080)：

09:22:21.299838000    10.159.63.104    10.161.241.208    HTTP    291    GET /eastsea/p/3764040.html HTTP/1.0 

这个请求响应内容的长度是：Content-Length 1154110（1.1MB）

云服务器（ECS）在收到请求后，发了一个ACK包：

09:22:21.354730000    10.161.241.208    10.159.63.104    TCP    66    http > 60895 [ACK] Seq=1 Ack=226 Win=66560 Len=0 TSval=16270579 TSecr=1049527471

接下来就是一堆的TCP segment of a reassembled PDU：

10.161.241.208    10.159.63.104    TCP    1514    [TCP segment of a reassembled PDU]

中间会出现一些错误：

1. TCP Dup ACK

10.159.63.104    10.161.241.208    TCP    78    [TCP Dup ACK 619713#1] 60895 > http [ACK] Seq=226 Ack=57921 Win=61440 Len=0 TSval=1049527542 TSecr=16270581 SLE=63713 SRE=75297

2. TCP Out-Of-Order

10.161.241.208    10.159.63.104    TCP    1514    [TCP Out-Of-Order] [TCP segment of a reassembled PDU]

3. TCP Fast Retransmission

10.161.241.208    10.159.63.104    TCP    1514    [TCP Fast Retransmission] [TCP segment of a reassembled PDU]

另外，中间也出现了大量的TCP Window Update：

10.159.63.104    10.161.241.208    TCP    66    [TCP Window Update] 60895 > http [ACK] Seq=226 Ack=175209 Win=16384 Len=0 TSval=1049528183 TSecr=16270632

最后在9:23:32才完成了响应内容的发送：

09:23:32.865387000    10.161.241.208    10.159.63.104    HTTP    486    HTTP/1.1 200 OK  (text/html)

Wireshark中记录的中整个发送耗时：

Time since request: 71.565549000 seconds