对不起，如果我听起来很愚蠢，但我是非常新的networking.My应用程序作为ESMS的smsc工作，似乎最近我们观察到提交的信息的ack大大延迟或ack根本不来。我可以看到在Linux的netstat输出发送队列的数量正在增加。取得一个tcpdump，我可以看到很多[TCP Dup ACK]，[TCP Out-Of-Order]，[TCP Retransmission]
我也看到wireshark
Smsc send mesg with seq:1 ACK:1 Len: 51 -->"213.132.40.140 -> 192.168.40.8 SMPP SMPP Deliver_sm" but we reply by 192.168.40.8 -> 213.132.40.140 TCP 42758 > dynamid [ACK] Seq=4141 Ack=52 Win=128 Len=0 46327 3464.532349 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] 43560 > dynamid [ACK] Seq=74521 Ack=34908 Win=128 Len=1380 46328 3464.532358 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] 43560 > dynamid [ACK] Seq=74521 Ack=34908 Win=128 Len=1380 46330 3464.711002 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] 43560 > dynamid [ACK] Seq=75901 Ack=34941 Win=128 Len=1380 46331 3464.711006 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] 43560 > dynamid [ACK] Seq=75901 Ack=34941 Win=128 Len=1380 46337 3465.372048 213.132.40.140 -> 192.168.40.8 SMPP [TCP Retransmission] SMPP Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok" 47148 3530.377438 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] [TCP segment of a reassembled PDU] 47149 3530.377446 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] [TCP segment of a reassembled PDU] 47151 3530.551594 192.168.40.8 -> 213.132.40.140 SMPP [TCP Retransmission] SMPP Submit_sm 47152 3530.551598 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] [TCP segment of a reassembled PDU] 47153 3530.551607 192.168.40.8 -> 213.132.40.140 SMPP [TCP Retransmission] SMPP Submit_sm 47154 3530.551609 192.168.40.8 -> 213.132.40.140 TCP [TCP Retransmission] [TCP segment of a reassembled PDU] 47163 3531.210403 213.132.40.140 -> 192.168.40.8 SMPP [TCP Retransmission] SMPP Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok", Submit_sm - resp: "Ok" No. Time Source Destination Protocol Length Info 47596 2017-10-10 16:04:11.548287 192.168.40.8 213.132.40.140 SMPP 73 [TCP Retransmission] SMPP Deliver_sm - resp: "Ok" Frame 47596: 73 bytes on wire (584 bits), 73 bytes captured (584 bits) Linux cooked capture Internet Protocol Version 4, Src: 192.168.40.8 (192.168.40.8), Dst: 213.132.40.140 (213.132.40.140) Transmission Control Protocol, Src Port: 53502 (53502), Dst Port: dynamid (9002), Seq: 613178, Ack: 160058, Len: 17 Source port: 53502 (53502) Destination port: dynamid (9002) [Stream index: 0] Sequence number: 613178 (relative sequence number) [Next sequence number: 613195 (relative sequence number)] Acknowledgment number: 160058 (relative ack number) Header length: 20 bytes Flags: 0x018 (PSH, ACK) Window size value: 546 [Calculated window size: 546] [Window size scaling factor: -1 (unknown)] Checksum: 0x7b3a [validation disabled] [Good Checksum: False] [Bad Checksum: False] [SEQ/ACK analysis] [Bytes in flight: 17] [TCP Analysis Flags] [This frame is a (suspected) retransmission] [The RTO for this segment was: 0.000011000 seconds] [RTO based on delta from frame: 47595] [PDU Size: 17] Short Message Peer to Peer, Command: Deliver_sm - resp, Status: "Ok", Seq: 6879, Len: 17 请帮助