Web Performance

YSlow:

Is a Firefox plugging , analyzes web pages and tells you why they're slow based on Yahoo's rules for high performance web sites.

https://addons.mozilla.org/en-US/firefox/addon/5369

This tool ranks all the pages from A to F.

Yahoo Exceptional performance Team:

http://developer.yahoo.com/performance/rules.html

Tuning Apache and PHP:

http://phplens.com/phpeverywhere/tuning-apache-php

Tuning Apache:

http://httpd.apache.org/docs/2.0/misc/perf-tuning.html

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Eduardo R. Coll