conntest.js

var http = require('http');

var requestCounter = 0;
var startedRequests = 0;
var endedRequests = 0;

http.createServer(function (request, response) {
    request.number = requestCounter++;

    console.log("#" + request.number + " started");

    startedRequests++;

    request.on('end', function() {
      console.log("#" + request.number + " ended");
      endedRequests++;
    });

    response.writeHead(200, {'Content-Type': 'text/plain'});
    response.end('Hi there\n');
}).listen(8080);

setInterval(function() {
  console.log("[TOTAL] " + requestCounter + " [S] " + startedRequests + " [E] " + endedRequests + " [S-E] " + (startedRequests - endedRequests));
}, 1000);

Ok thank you very much for your time. I appreciate your help a lot. I will investigate on my side. Maybe it's the "formidable" library I am using.