Problem: I have poor performing pges and I need to see which pages are causing my issues, I have the Developer dashboard or web testing in Visual Studio 2012 Ultimate but a nice quick way to identify the issue is to use fiddler with a slight customisation.
Resolution: Create a TTL column in fiddler to see how long each request is taking. In Fiddler press Ctrl + R, this opens the editor CustomRules.js. Edit as shown below.
In my scenario the page is taking 6 seconds to load as shown in yellow highlight. My SQL database hosting my SP Config database could not grow. Once I correct this, my TTL is under 0.1 seconds on a blank default publishing page.
See other related Fiddler posts
Enable the developer dashboard post.