FireFox页面加载速度分析

Page Speed

	What is Page Speed? Page Speed is 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.
	How does Page Speed work? Page Speed performs several tests on a site’s web server configuration and front-end code. These tests are based on a set of best practices known to enhance web page performance. Webmasters who run Page Speed on their pages get a set of scores for each page, as well as helpful suggestions on how to improve its performance.
	Why should you use Page Speed? By using Page Speed, you can: Make your site faster. Keep Internet users engaged with your site. Reduce your bandwidth and hosting costs. Improve the web!

Releasing the Page Speed SDK (all open source) is one step closer to having a common performance metric across all web development tools and environments. Imagine being able to get the same performance analysis results from Firebug, Web Inspector, HttpWatch, Fiddler, Keynote, and Gomez. This will help us develop a common vocabulary and bring more consistency and quality to the field of web performance optimization.

This is a quote from Steve on the new HAR to Page Speed work that he has built on top of other work:

The importance of an industry standard HTTP archive format is huge. Adoption of HAR allows companies and data gathering institutions (such as the Internet Archive) to record the web page experience and pull it up later for further review. It provides a way to exchange information across tools. And it provides an open standard for sharing web loading information between individuals – developer to developer as well as customer to customer support.

In their last few releases the Page Speed team has mentioned porting their performance analysis logic from JavaScript to C++. The resulting library is called “native library” – not too jazzy. But last week they released the Page Speed SDK. The documentation is slim, but I noticed a command-line tool called har_to_pagespeed.

I downloaded the SDK. It built fine on my Dreamhost shared server. Then I wrapped it with a file upload PHP page and created HAR to Page Speed.

Once you upload a HAR file you get page speed info and more:

For a full example, check out a CNN.com archive.