Memory management issues in JS / AJAX

[Bob Vu]

The Javascript in my web page (updated using AJAX) is causing symptoms like memory leaks on client machines. The memory usage continues to rise until the browser freezes. I have isolated it to the bit of code shown below. Does anything here stand out as a reason fom memory not to be released? Many thanks in advance.

function ajaxLoaderVWSF(url) {
  if (document.getElementById) {
    var x = (window.ActiveXObject) ? new ActiveXObject("Microsoft.XMLHTTP") : new XMLHttpRequest(url);
  }
  if (x) { // got something back
    x.onreadystatechange = function() {

                  
                              //main fuction goes here


                                       } 
    x.open("GET", url, true);
    x.send(null);


    if ( (maxupdates == 0) || (updates < maxupdates-1)) {
      setTimeout("ajaxLoaderVWSF(flashFile + '?' + new Date().getTime())", reloadTime);
    
        }
  }

}

[Rabbit]

Depending on how often that function is called, you're constantly creating new ActiveXObjects without freeing them.

[Bob Vu]

Can you suggest a method to free them? I tried setting x to null, deleting x, various other things without success.

[Rabbit]

After some research, it looks like you are unable to free up the memory because you've created a closure by assigning a reference to a function.

This page has a lot of different ways of dealing with closures: http://jibbering.com/faq/notes/closures/#clClose.

[Samishii23]

Not to not answer the question... But jQuery could make the coding easier for you, and they probably already accounted for this stuff.