How to tracking down slow loading JS in IE8?

One of the websites I work on loads extremely slow in IE8 and Im trying to track down the culprit. The website is virginwines.com

Anyone have any开发者_C百科 advice around how I can use browser tools to figure out which JS is causing the issue(s)?

You can use the Developer Tools Profiler in IE8 to see where it is spending most of its time.

You can use Fiddler2 - a debugging proxy - to view traffic between IE and the site. With IE8, the site is getting stalled on 8 images with a no-cache directive that are returning a 404.

#   Result  Protocol    Host    URL Body    Caching Content-Type    Process Comments    Custom  
9   404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderTopLeft.png 1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:00 GMT    text/html;charset=UTF-8 iexplore:1784           
10  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderTopCenter.png   1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:01 GMT    text/html;charset=UTF-8 iexplore:1784           
11  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderTopRight.png    1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:01 GMT    text/html;charset=UTF-8 iexplore:1784           
12  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderMiddleLeft.png  1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:01 GMT    text/html;charset=UTF-8 iexplore:1784           
13  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderMiddleRight.png 1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:02 GMT    text/html;charset=UTF-8 iexplore:1784           
14  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderBottomLeft.png  1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:02 GMT    text/html;charset=UTF-8 iexplore:1784           
15  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderBottomCenter.png    1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:03 GMT    text/html;charset=UTF-8 iexplore:1784           
16  404 HTTP    www.virginwines.com /images/us/en/brands/virgin/internet_explorer/borderBottomRight.png 1,529   no-cache  Expires: Wed, 08 Dec 2010 17:42:03 GMT    text/html;charset=UTF-8 iexplore:1784           

As mentioned by others, you can use the IE developer tool bar (F12) and Firebug Lite is available for most major browsers. (If you're using FireFox, you should already be familiar with the full Firebug.)