Node.js' net socket memory leak?

package.json

{
  "dependencies": {
    "heapdump": "^0.2.10"
  }
}

test.js

var net = require("net")
,   heapdump = require("heapdump");

function onConnection (client) {
  client.on("data", function (data) {
    client.end();
  });
};

function onListen () {
  var socket = net.connect({host: "127.0.0.1", port: 3000});

  socket.bigBuffer = new Buffer(50000000); //50MB Buffer

  heapdump.writeSnapshot(__dirname + "/initial.heapsnapshot", function writeInitialSnapshot () {
    console.log("Wrote initial heap snapshot");
    socket.write("data");
  });

  socket.on("close", function () {
    writeEndSnapshot();
  });
};

function writeEndSnapshot () {
  setTimeout(function () {
    console.log("Running GC");
    gc();

    heapdump.writeSnapshot(__dirname + "/final.heapsnapshot", function writeFinalSnapshot () {
      console.log("Wrote final heap snapshot");
    });
  }, 1000);
};

net.createServer(onConnection).listen(3000, onListen);