I finally got around to installing Xdebug on my development environment and have decided it is the best thing since sliced bread. Installation was a breeze and the information it provides when something has gone wrong is incredibly helpful during debugging.

He explains what the software does, how it can help you and your development - even how to get it up and running on your PHP install (seriously, it's drop dead easy...why haven't you installed it yet?). He also points to the tutorial on the Zend Developer Zone introducing the powerful tool.

The PHP Development Tools (PDT) plug-in, when installed with Eclipse Europa, gives you that ability to quickly write and debug PHP scripts and pages. PDT supports two debugging tools: XDebug and the Zend Debugger. Learn how to configure PDT for debugging PHP scripts and discover which perspectives you use when taking closer looks at your scripts.

You'll need to have a machine with PHP, Eclipse, Apache and the PHP Development Tools already installed to follow along (as well as a trial version of the Zend Studio Web Debugger). They also include the methods for setting up XDebug as the debugger.

Here's more information from their press release:

Blue Static today is announcing the release date of MacGDBp, a native Cocoa application that allows Web developers to debug their PHP applications. The tool makes use of the Xdebug (http://www.xdebug.org) PHP extension that provides remote debugging functionality. Blue Static will be releasing the software under the GNU GPL version 2 on the morning of Tuesday, 17 June 2008.

The interface for the application is modeled after the XCode product from Apple to help integrate it more fully into the OS look and feel. It will require Mac OS X 10.5 Leopard to run and screenshots of the tool can be found here and here.

Webgrind, the web frontend to Xdebug has been updated to version 0.7 with a few new features like: Support for directly loading a report through hash in url, Visual breakdowns of internal, class and procedural functions and calls to include/require and Version checking.

This new version (0.7) can be downloaded directly from its Google Code page.

Since a few days, there is a new package in Debian: php5-xdebug. After a few years of talking licenses, due to the help of Martin Meredith and Francois Marier Xdebug can finally be installed with apt-get.

XDebug is a debugging and profiling tool that adds additional information (more than just the usual "error on line..." sort of thing) to the output of your PHP scripts. It also adds more complex functionality like profiling and code coverage reports run on your applications.

For quite a while in the PHP Community (And even myself) I have heard people asking about either an online tool to work on cachegrind output files or a cross platform tool that would have the ability to do what KCacheGrind does on Linux but for Windows and OSX.

He mentions the origin of the idea for a cachegrind app as a part of the Google Summer of Code (that did get accepted and will be worked on by Chung-Yang Lee). The other, Webgrind is an independent project from the other but looks equally as promising.

Check out Vinu Thomas' thoughts on the matter too.

My about page has mentioned a web based frontend for Xdebug for some time. The project has a name now: The idea for Webgrind, a spin on Valgrind, came from lack of profiling tools for PHP, particularly on OSX. Though it is possible to install kcachegrind on osx it seems overkill for many uses and is definitely not as easy as unzipping a folder to the webroot.

He and Jacob Oettinger have started up the project and have posted some initial code over on the Google Code page for Webgrind. You can check out a screenshot of it in action here too.

• PHP Optimizer by Samuel Graham Kelly IV, mentored by Derick Rethans
• gsoc:2008 - XDebug by Chung-Yang Lee, mentored by David Coallier
• PHP Bindings for Cairo by Akshat Gupta, mentored by Anant Narayanan
• Implement Unicode into PHP 6 by Henrique do Nascimento Angelo, mentored by Scott MacVicar

You can check out more information on the projects (including links to their individual pages) on this page of the Google Code website.

Xdebug is a PHP extension which helps you to understand, debug and profile PHP. It can help you to find bottlenecks or give you an quick overview what happens in code you aren't familiar with, yet.

The post gives a brief overview of the installation of the extension (building a shared module) and shows how to get started with profiling an application. He talks about the cachegrind tool you can use to parse the results and the kcachegrind app that will make the results a bit more visual.

As a bonus, he also throws in a bit about function tracing - picking out each small bit of functionality in the code (the function/methods) and gathering stats for each.

Some websites use other technologies like Java and face the exact same problems. There are different variables involved here and the most common one is database. So I thought i would post a couple of articles related to performance and tuning.

This this post of the series focuses on the first of the two - APC - and talks about places it's used and includes some general performance recommendations. These include "Don't try to throw everything at your poor database" and the importance of XDebug.