[Demexp-dev] Issue to open an RPC TCP connection on the Internet

[David MENTRE]

Hello Gerd,

For my application, I'm using RPC over TCP. When used over a real
Internet, with some latency, I noticed that the connection can fail
several times ("Connection refused", ECONNREFUSED) before being
successful. In other words, I need to launch the client several times
and after two to three attempts, it finally works. I also noticed that,
in case of failure, the answer comes quite early, after a few seconds.

I'm using a very usual code to open the TCP connection:

    let client = Demexp.V1.create_client 
        (Rpc_client.Inet (pref#server_name, pref#server_port)) Rpc.Tcp in

I'm using RPC 0.4.4.

Do you use specific TCP socket option when opening the TCP connection? A
smaller timeout? (looking at src/rcp/rcp_client.ml:create, it does not
seem to be the case, but I don't understand all of your code)

Or would this "Connection refused" message be related to another issue?
Any hint?

As a related question, my client is an interactive one, the RPC being
called after user input. I'm thinking at setting the Nagle algorithm in
order to reduce the latency before having an answer. What do you think
of it? Have you tested it? Is it worth it?

Best wishes,
david

PS: I still not have tested the I18N extensions to WDialog: lack of time
    and lack of motivation. Put this is at the top of my todo list.
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pub  1024D/A3AD7A2A 2004-10-03 David MENTRE <address@hidden>
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