What is the preferred way to handle this TCP connection in C#?

Question

I have a server application (singleton, simple .NET console application) that talks to a GlobalCache GC-100-12 for the purpose of routing IR commands. Various .NET WinForm clients on the local network connect to my server application and send ASCII commands to it. The server application queues these ASCII commands and then sends them to the GC-100-12 via a TCP connection.

My question is, what is the best way to handle this connection from the server's point of view? I can think of two ways:

1. Create and Open a new TcpClient for each individual request. Close the TcpClient when the request is done.

2. Create and Open one TcpClient when the server starts and use a keep-alive (if necessary) to keep the connection open for the lifetime of the server object.

I ask this question because I wonder about the overhead of creating a new TcpClient for each request. Is it an expensive operation? Is this a bad practice?

Currently I am doing #1, and printing the results of each transmission to the console. Occasionally some connections timeout and the command doesn't get routed, and I was wondering if that was because of the overhead of creating a new TcpConnection each time, or if it is due to something else.

I can see #2 being more complicated because if the connection does drop it has to be recreated, and that will require a bit more code to handle that circumstance.

I'm looking for any general advice on this. I don't have a lot of experience working with the TcpClient class.

Answer 1

We had a simillar case of opening a telnet session to an old PICK based system. We found that the cost of opening the TCP connection each time a request came in was fairly expensive, and we decided to implement a no-op routine to keep the connection open. It is more complex, but as long as your end point is not trying to serve many many clients then pinning a connection sounds like a viable solution.

You could also set it up to have a timeout, if you want to prevent keeping a connection open when there is no traffic. Five minutes of no activity then shut down the connection.