Using keepalive causes MaxListenersExceededWarning: Possible EventEmitter memory leak detected

[aneilbaboo]

Add a keepalive agent to the options of your http agent as in https://github.com/node-modules/agentkeepalive

Then run several test, and see:

This is due to the socket accumulating timeout listeners inside the realReq.on('socket',... code:

cache.js:333

      realReq.on('socket', function(socket) {
        socket.on('timeout', function() {
          timedOut = true;
        });
      });

Because the socket is reused, it keeps accumulating timeout listeners.