I am using the WCF NetTCP (v3.5) communicating with a third-party application(running under .Net 4.0) and from time to time there were very large latency in the communication.
The third-party applicationis the client side while mine is the server side. Wireshark showed that most of the latency was spent betwee the time the third-party application sent and the time the TCP packet got shown on the Wireshark on the client side. For example, if the third-party application sends the message at 1:00:00 am, the Wireshark at the client side shows the packet at 1:00:10 am. The 10 second is spent before it hits the network. Is this indicating that the third-party application has a sort of contention problem? Right now, it is suspected that the server side(my application) did not pick up the packet fast enough even though the CPU is low on the server side and TCP window size is 64K, which does not indicate any problem on the server side. Any suggestion for troubleshooting this issue?