WebSocket CLOSE_WAIT on disconnect

[rbranson]

If I open a bunch of WebSocket connections and then drop them, they stay in the CLOSE_WAIT state, which uses up a file descriptor until a timeout (a few minutes). This means you can pretty quickly hit max file descriptors (typically set to 1024 or 4096) if you've got a lot of people connecting and disconnecting. One can use lsof or netstat to see all the open file descriptors in CLOSE_WAIT state. A fix in the websocket.js code is to destroy the connection after receiving the end event:

this.connection.addListener('end', function(){
            self.connection.destroy();
    self._onClose();
});

This seems to solve the problem.

[saschagehlich]

I absolutely agree. This drives me nuts, can't release my project because of that.

[prabgupt]

Has this issue been fixed yet? I too am facing this problem and there are lots of connections in our env hanging on CLOSE_WAIT. To remove them, we don't have any option other than restarting the server again.

I tried workaround mentioned by Rick but still no luck. Can someone help in here as we don't want to keep re-starting out server periodically due to CLOSE_WAIT connections exceeding max file descriptors? I have already increased file descriptor limit and don't want to increase it more. Anyways even after doing so, still issue will remain.

[saschagehlich]

Well, I updated to node v0.3.6 and the latest socket.io which works fine

[prabgupt]

thanks Sascha for such a quick reply :) I have updated socket.io. Let me try updating node as well and will then update this thread with my findings so as to let all know.