Add These Website Performance Test Tools To Your Toolkit

I've listed some performance testing resource links that are worth looking at if you do any sort of website performance testing.
One of the more difficult tasks when conducting load and stress testing is identifying bottlenecks and suggesting areas on which developers should concentrate. Often this type of testing uses tools that are tuned to put a load on a website (e.g. JMeter) and consequently generates a lot of test data, primarily because these tools simulate lots of users. It helps to have another perspective to corroborate the data from your load tests. This is where these website performance tools may help:

Speed Tracer. Speed Tracer is a Google Chrome extension that helps you identify and fix performance problems in your web applications. It visualizes metrics that are taken from low level instrumentation points inside of the browser and analyzes them as your application runs. Using Speed Tracer you are able to get a better picture of where time is being spent in your application.

YSlow. This tool analyzes web pages and why they're slow based on Yahoo!'s rules for high performance web sites. YSlow uses Yahoo!'s Smush.it service.

Page Speed. An open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them.

Google Web Toolkit (with Speed Tracer). Google Web Toolkit (GWT) is a development toolkit for building and optimizing complex browser-based applications. GWT is used by many products at Google, including Google Wave and Google AdWords. It's open source, completely free, and used by thousands of developers around the world.

Web Performance Best Practices. When you profile a web page with Page Speed, it evaluates the page's conformance to a number of different rules. These rules are general front-end best practices you can apply at any stage of web development. We provide documentation of each of the rules here, so whether or not you run the Page Speed tool — maybe you're just developing a brand new site and aren't ready to test it — you can refer to these pages at any time. We give you specific tips and suggestions for how you can best implement the rules and incorporate them into your development process.