关于TCP交互数据流的延迟ACK的疑惑

kugong1119

大家看下我下面的tcpdump信息，客户端每隔12ms给服务器发送一个数据长度14字节的包，服务器端不做任何响应。
根据时延ACK的规则，服务器端所有的ACK都是时延ACK，那么它们之间应该相差200ms的整数倍才对啊，下面ACK的时间来看，明显不符合这个规则啊
还有人说时延ACK的延迟可能是40ms，但是下面的时间也不符合
有没有大侠指点下 感激不尽

18:11:47.081128 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: S 4100329860:4100329860(0) win 2920 <mss 1460,sackOK,timestamp 3511212858 0,nop,wscale 2>
18:11:47.081139 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: S 2319613295:2319613295(0) ack 4100329861 win 5792 <mss 1460,sackOK,timestamp 8963531 3511212858,nop,wscale 2>
18:11:47.114526 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: . ack 1 win 730 <nop,nop,timestamp 3511212866 8963531>
18:11:47.114537 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: P 1:15(14) ack 1 win 730 <nop,nop,timestamp 3511212866 8963531>
18:11:47.114541 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: . ack 15 win 1448 <nop,nop,timestamp 8963539 3511212866>
18:11:47.147697 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: P 15:43(2 ack 1 win 730 <nop,nop,timestamp 3511212874 8963539>
18:11:47.147717 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: . ack 43 win 1448 <nop,nop,timestamp 8963548 3511212874>
18:11:47.180762 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: P 43:71(2 ack 1 win 730 <nop,nop,timestamp 3511212883 8963548>
18:11:47.180777 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: . ack 71 win 1448 <nop,nop,timestamp 8963556 3511212883>
18:11:47.213897 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: P 71:99(2 ack 1 win 730 <nop,nop,timestamp 3511212891 8963556>
18:11:47.213907 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: . ack 99 win 1448 <nop,nop,timestamp 8963564 3511212891>
18:11:47.247071 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: P 99:127(2 ack 1 win 730 <nop,nop,timestamp 3511212899 8963564>
18:11:47.247080 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: . ack 127 win 1448 <nop,nop,timestamp 8963573 3511212899>
18:11:47.280057 IP BeiAi_10_144_16_78.soso-idc.com.54799 > JingKai_10_161_29_182.soso-idc.com.65000: P 127:141(14) ack 1 win 730 <nop,nop,timestamp 3511212907 8963573>
18:11:47.280067 IP JingKai_10_161_29_182.soso-idc.com.65000 > BeiAi_10_144_16_78.soso-idc.com.54799: . ack 141 win 1448 <nop,nop,timestamp 8963581 3511212907>

drangon

ACK明显是没有时延嘛，应该是加了NODELAY

kugong1119

nodelay的配置项值是0的

kugong1119

自己顶一下
请大侠指点下哈

hhg12304

推荐你看一下，TCP-ip详解卷一 第19章 还是20章  延时ACK  NAGLE算法，也许有帮助！