title: Used memory never released in node js. Very strange
body: <p>I've just finished to develop my first node.js app and now i'm testing it on my VPS. observing the use of resources of the process "node", I have noticed an increase in memory usage when a page (especially some) is requested. In particular, if the requested page is a static page, the increase is minimal. If the requested page is /admin the increase can be 1mb! Of course, when /admin is requested, my server does more things than serve a static page. He connects to mongodb, he performs 4 "find", he binds the results to an html template using <a href="https://github.com/Xavi-/bind-js" rel="noreferrer">bind</a>. Now, what's the problem? This memory used, will be never released!!! So I thought there was a logical error in my code but then I did another test much more interesting.</p>
  
  <p>Consider this very simple nodejs server:</p>
  
  <pre><code> var http = require('http');
  http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});
    res.end('Hello World\n');
  }).listen(3000, 'my_public_ip');
  </code></pre>
  
  <p>if I try to make multiple requests with browser (simply by holding f5 for one minute), memory usage grows slowly and the memory used by the process will never be released, even after a long time and after closing the browser.  Now, it's probable that in my /admin code there is some error (1mb of memory used and never released for each requests it's very high!), but i think that it's very strange that memory used by the simple script above will be never released! What do you think about this? There is a way to avoid it?</p>
  
  <p>Also , (in my real server) , I used <a href="https://www.npmjs.org/package/memwatch" rel="noreferrer">memwatch</a> in thys way:</p>
  
  <pre><code>    var memwatch = require('memwatch');
      memwatch.on('leak', function(info) {
         console.log(info); 
         process.exit(1);
      });
  </code></pre>
  
  <p>If I perform multiple requests with browser , after about 10 seconds that i'm doing it, the process will exit and this is the error:</p>
  
  <pre><code>{ start: Wed Nov 26 2014 08:21:07 GMT-0500 (EST),
    end: Wed Nov 26 2014 08:22:04 GMT-0500 (EST),
    growth: 4775624,
    reason: 'heap growth over 5 consecutive GCs (57s) - 287.65 mb/hr' }
  </code></pre>
  
  <p>What does it mean?? It seems be related with garbage collector! I know that it would be better to paste my /admin code here but the snippet is very long and is related to global variables, so is impossible to understand without a copy of 200 lines :D. If you need more info i will give you! </p>