DynaTrace AJAX edition is great tool for alleviating webapp performance troubleshooting headaches. It can be downloaded for free, and once set up, can trace your browser actions (i.e. the website causing the headache), storing and displaying myriads of key performance indicators. A great thing about the tool is that you can measure and analyze end-to-end performance, meaning you get to peek at whats going on at the web server end. And the ability to trace click events, button events and other minute details along with their metrics and KPI’s are a gift from heaven. The tool can be downloaded from here once you register (registration is free). A great primer for using the tool can be found at this link, where the views and metrics displayed by the tool are explained in great detail.