Leverage YSlow for Performance

A couple of years ago, the smart folks at Yahoo realized a wonderful tool called YSlow. This is a plug-in for the Firefox browser that leverages another wonderful plug-in called Firebug. These two tools are a must for anyone in the business of web performance monitoring.

YSlow does a number of things, but the best place to start is the performance summary of a web page:


As you can see from the picture on the YSlow site, it will rank the web page under the YSlow 13 Performance categories. While it may not be the be-all end-all answer to solving your web performance tools, it really does give you a good start and a model to manage your web site's peformance. What is really the best part is that others can use it (since it's free to anyone) and get the same results that you do. The hardest part in discussing performance is establishing baselines to optimize and the Yahoo performance best practices are certainly worth leveraging.

But the best part of YSlow is the full object download option. Yahoo calls this the web page components, but it shows you all the objects that compose your page in a "waterfall" view, which gives you a poor man's view of performance (versus the one provided by Gomez).

The component view shows you all you need to uncover the performance hairballs of your site. All the large objects, any MIME-type mismatches, IP address of the source. Awesome.

In summary, YSlow is an amazing tool and provides the Performance Analyst a wonderful tool to help customers optimize their web sites.