The PHP 5.4 includes 7 main optimizations that made PHP work more efficiently in terms of the speed and memory usage efficiency. That is the main topic discussed in episode 25 of the Lately in PHP podcast on which Manuel Lemos received Gustavo Lopes, a PHP core developer.

You can either listen to this latest episode through the in-page player, by subscribing to the blog's feed. Additionally, you can also watch the video of the interview as recorded via Google Hangouts.

PHP 5.4 introduced several performance optimizations. One of them was not discussed much in the PHP community but it may affect the performance of your code depending on the way you write it.

He gets into some of the details surrounding the variable access optimization, pointing out how to get the most out of this improvement. He also does a bit of speculation about future versions of the language, including the possible introduction of "Just In Time" compilers.

This tutorial is going to assume that you have at least a beginner's understanding of PHP and the WordPress syntax. Though we'll be covering everything, some knowledge beforehand will help you grasp the concepts much more easily. I'll also assumes that you have a WP blog setup and ready to go.

The plugin takes out useless meta tags, unloads unneeded filters and handles some SEO work like adding tags and an excerpt into the post's header information. The break the plugin down into the different parts and include the code to get each of them working including a call to optimize all of the tables in your current WordPress install's database.

PHP is easy...as programming languages go, that is. You can build sites in a real hurry. [...] Still, sooner or later success catches up with you and you want your site to cope with Serious Traffic...or cope with moderate traffic on a cheap virtual machine...or at the very least, not be dog-slow with just a handful of users on the system.

He mentions things that can slow down the application (like timeouts on web server connections or not optimizing the site with a "thin" server for non-PHP requests). He mentions the alternative PHP cache (APC) as one possible way to help, some tips on making your Apache server more efficient and pushing those lighter requests off to a smaller, built-for-speed server using FastCGI.

This week's chapters explores some of the performance issues and tactics worth being aware of when developing Zend Framework, and indeed other, applications. It's a rather long piece of work but I hope it proves enlightening. Comments are, as usual, welcome and you can attach them to any paragraph in need of attention.

Next up will be a chapter focusing on the Model portion of the MVC structure, so keep an eye to his blog for more chapters as they're released.

I've recently been working on a project trying to take an existing customized wordpress site and create automated integration tests around parts of it. I'm using phpUnderControl, phpUnit, Selenium RC, Firefox, Xvfb (virtual frame buffer) and...well, I think that's it.

He mentions the two issues he came across, both with the WordPress software (the "siteurl" setting and the pathing for the templates). He recommends that application code be portable to avoid problems like these. Applications that can be dropped in anywhere and "just work" can help not only make life easier for the installer but also for the tester.

I'd like to say that this book has changed my way of thinking about SEO Professionals, but it hasn't. It has, however, given me enough information so that I can make my own projects more SE friendly and allow me to help my friends do the same.

Cal talks about the contents of the book, including his favorite chapter (chapter 2) that gives a quick-hit primer to the world of search engine optimization. The rest of the book is divided up into specialization topics inside of SEO like "SE Friendly URLs", "Duplicate Content" and "Link Bait". Plus, check out what Cal has to say about one of the Appendixes...

PHP's creator, Rasmus Lerdorf, gave a surprising talk on building PHP rich web applications using PHP5-suprising, because fully half the talk focused on low-level PHP optimization techniques. The slides are available online.

Kevin gives an overview of the talk, mentioning some of Rasmus' examples, the bottlenecks he defined, and the time spent on the new functionality in the PHP 5 series.

The MySQL list includes things like:

• MySQL is interpreted from right to left so you should put the most significant limiters as far to the right as possible.
• Use indexes on the columns in the WHERE clause and on the columns you want to ORDER BY.
• Sometimes mysql_free_result() end up wasting more memory than it saves. Check the difference with memory_get_usage().
• Use NOT NULL as default value as much as you can, it speeds up execution and saves one bit.

And the PHP list includes:

• When echoing strings it's faster to separate them by comma instead of dot.
• Unset your variables to free memory, especially large arrays.
• Many code blocks might slow down the interpretation a little bit.

There's also all sorts of other tips down in the comments as well.

The author follows this up with a few more stats before getting on with the heart of the article - the tips and tricks. They demonstrate a sample function to help test the speed of the script before looking at different topics of optimization - outputting an array, regular expressions, using references, and file inclusion. For each, there's a "slow way" and a "fast way" - I wonder which is the better choice...