Tuesday 12 July 2011

Firefox 5.0 Firebug 1.8 Memory Leak Problem

Firefox 5.00 with Firebug 1.8.0b5 on Windows 7 64 bit causes Memory Leak

I came across a problem with Firefox 5.0 and Firebug 1.8.0b5 today that basically leaked memory like an open oil well and hung my PC every time I tried to open up a basic popup window from a page using Javascript.

My PC is running the following:

Windows 7 - Dual Core - 64 Bit
Firefox.exe *32 - version 5.0
Firebug 1.8.0b5

This problem has only started occurring since my latest upgrade and I narrowed it down to Firebug by disabling each plugin one by one.

I can replicate the problem on one particular page quite easily which has a link with a simple javascript: window.open(url) function that opens up a little static html page.

When I now click the link the popup opens full size rather than the dimensions set 400px * 400px and there is nothing on the page - just a blank screen. Viewing the source shows nothing at all.

This page used to work fine before the update.

It still works on all other browsers Chrome, Safari, IE (6 to 9) and it still works in Firefox 5.0 on 32 bit machines so I am not sure whether it's a 64 bit problem or not.

Viewing my Task Manager window I can open Firefox and I can get my Firefox to use beyond 1GB of memory and 50% CPU (the whole of one of my two processors) with only one single window and tab open all within 5 minutes.

Earlier today it was using over 3GB of memory!

Another clue is the fact that the error console is permanently full of these error messages:

attempt to run compile-and-go on a cleared scope
line 156

Hitting clear just fills up the whole of Firebug's console log instantly with the same message.

The only way I have found to solve this problem is to disable Firebug and not use the "Restart Firefox" link as this seems to just ramp the memory up without shutting the process down first.

I usually have to kill the process through Task Manager as clicking the close button doesn't do anything the majority of the time.

If anyone else has similar problems please let me know.



nice post man,
thx u

Anonymous said...

I'm having the exact same problem in Windows XP 32 bit. Does anyone know how to disable or uninstall Firebug (it's a pretty much useless piece of software anyway)? Thanks.