Profiling tool for HTML, PHP and Javascript

Is there any free profiling tool with which I can measure the performance of HTML, PHP and JavaScript code in开发者_如何学JAVAdependently?

For the performance of PHP I use Xdebug with cachegrind turned on. For HTML and Javascript I like to use firebug / yslow.

For html/javascript try:

http://developer.yahoo.com/yslow/

this link has 2 tools. Firebug (profile your javascript). and YSlow testing page load times and gives you suggestions on how to fix it.

If your php pages are using a database, your queries will almost certainly be the most expensive part of any request. And that gets worse with time as your dataset grows.