[Greasemonkey] memory leak when using DOMNodeInserted

Wed Jun 28 17:27:40 EDT 2006

For some reason, my GM script causes a massive memory leak when using event
"DOMNodeInserted"

I have a complex function (called go() below) that runs when the page loads
and when it changes. The only thing it does is hides elements by setting
style.display='none' and optionally style.visibility=''
The only exception is when pass=1 (i.e. only once) a style tag is appended
to the <head> children.

The code below watches for DOMNodeInserted events and tries to only run go()
after no inserts have occurred after 200ms. 

My test case is that I run this script without listening to DOMNodeInserted
and open 25 myspace pages - Firefox goes to about 320mb, and then close all
tabs - and it returns to 100mb.
When I listen to DOMNodeInserted, it stays at 320mb.

Any ideas?

var pass=0;
var change_count=0;
var notify_count=0;
var scheduled = false;
function notifyChange() {
	if (notify_count==change_count)
		go();
	if (notify_count!=change_count) {
		schedNotify();
		return;
	}
	scheduled=false;
}

function schedNotify() {
	scheduled=true;
	notify_count=change_count;
	setTimeout(function(e) { notifyChange(); },200);
}

go();
if (true) {
	window.addEventListener("load", function(e) {
		document.addEventListener("DOMNodeInserted", function(e) {
			change_count++;
			if (!scheduled && change_count>2)
				schedNotify();
		}, false);
	}, false);
}