If you're not familiar with XHGui it's a fabulously easy and friendly way to profile your application; to understand which method calls in a page take the time and how many times they are made, so you can improve the performance of your application. All these instructions are for my 32-bit Ubuntu 12.10 system, hopefully they will work for you or you'll be able to adapt them as appropriate.

She lists the dependencies you'll need to have installed before you can get XHGui working correctly including a MongoDB instance and the PECL xhprof extension. With those all set to go, you can go grab the latest XHGui from github and drop it into place.

Mark Story & I are pleased as punch to introduce XHGui on MongoDB. Our goal was to get as close to the original feature set of the tool I worked on a few years ago (which leveraged the starting point provided by Facebook) and then to release what we had. What we've got now works; there's still a good distance to go, but we think it's far enough that we can ask for help form the community at large.

The tool collects XHProf data and stores it into a MongoDB database and allows you to view recent activity. There's a few warnings that he includes with the post, so be sure to read those through if you plan on using the tool.

PHP introduced DTrace support with PHP 5.3, enabling probing points in the PHP executable that can be used to simplify probing of PHP applications without having to the PHP implementation details. We enabled probes on function calls, file compilation, exceptions and errors. But this has always been limited to the operating systems that support DTrace. With the popularity of DTrace, Systemap programmers decided to add a DTrace compatibility layer that allows to use DTrace probes as Systemtap probing points as well.

Thanks to a recent commit to the PHP 5.5 branch, your PHP installation (compiled with DTrace support) can be executed with the "stap" command and searched for probe points. He includes a simple Systemtap script that counts the calls of a specific function to get you started.

Xdebug is a free and open source project by Derick Rethans and is probably one of the most useful PHP extensions. It provides more than just basic debugging support, but also stack traces, profiling, code coverage, and so on. In this article you'll see how to install and configure Xdebug, how to debug your PHP application from Netbeans, and how to read a profiling report in KCachegrind.

He walks you through the installation process (installing it from a package, not compiling) and how to enable it in your "php.ini" configuration file. He also shows how to hook it into the debugger on your IDE (in this case Netbeans) to receive debug messages and be able to step through the code to easily locate the issues. Also included is some basic information about profiling your application and viewing the resulting data in something like Kcachegrind or Webgrind

Profiling is the process of measuring the execution time of each function or method call involved in servicing a single page request. The data collected from this process can reveal issues such as a particular method taking a long time to execute or being called a large number of times. Profiling a PHP script generally requires installing a PHP extension. The two more popular extensions for this purpose are Derick Rethans' Xdebug and Facebook's XHProf. This article will focus on XHProf.

He walks you through the installation of both and shows you some sample results of the profiling of a simple application and how you can compare the results across profiling runs. Additionally, if you install graphviz support, you can generate the call stack output in a visual form to make for easier consumption.

In this Nettuts+ mini-series, we'll build a web application from scratch, while diving into a great new PHP framework that's rapidly picking up steam, called Laravel. In this lesson, we'll be working on an integral part of any web application: the Models. Along the way, we'll learn about Laravel's amazing ORM implementation: Eloquent.

The tutorial introduces you to the concept of "Models" and some of the conventions that surround them in the Laravel framework. They show some of the most common operations (CRUD) and how to define relationships between the models (has many, has one, etc). They apply this to their "Instapics" example application, creating the interfaces for the users, profiles, relationships, photos and comments. They include the code to create the controllers/views to go along with them, making a simple interface to show users and their photos.

You can find out more about the Eloquent ORM in this section of the Laravel manual.

The main aim of this application is to go familiar with the Google Plus API usage. Google Plus provides an extremely easy to use API to access the public contents on it. Here we will create a simple search application to search user profiles on Google Plus.

Complete code is provided in the post (PHP) and instructions on setting up an "application" on G+ so you can get the keys needed to connect to the API. You can see it in action in the live demo or just download the source to get started.

XHProf will provide you with a hierarchical profile of the functions your application calls, allowing you to follow the chain of events that lead up to resource intensive code running. You'll be able to see exactly how much wall time (the actual time elapsed), CPU time and memory your application uses. This tutorial will help you get XHProf installed on your server, and integrated with your CodeIgniter application via hooks so that you can start profiling your application, in a production environment, straight away. Everything you see here was written for Ubuntu 10.04 - the latest LTS release at the time of writing.

They walk you through the installation of the tool (via a wget of the source), show you how to integrate it with CodeIgniter via hooks and include a simple class that is called to execute and report on the findings. Some sample output is included as well as some general tips on interpreting the results.

A profiler gives you the ability to trace the performance of your code through every function call and create an overview of your system's performance over a certain time period and helps you make intelligent decisions about where to look for problems. [...] But what if you're in an environment where you can't install [the xdebug or xhprof] extension? Luckily, php has a built-in function called register_tick_function that gives you a way to hook in to every user function that's called. With this, you can write a profiler yourself.

A bit of sample code illustrates his method - it defines a "do_profile" function and assigns it with the register_tick_function call. This function generates a debug backtrace and echos out the function path it took to get to that spot (output is included). He provides code for a bit more useful profiling and points out that it could easily be graphed to help visualize the problems. Also included are a few caveats to watch out for when using this method of profiling.

The web is full of useful advice focussed on pushing out the last bit of performance of your code. They mention trivial changes. like changing every occurrence of print with echo even suggesting to use for instead of foreach. These optimisations help, but you are not going to notice it unless they're in a tight loop with many iterations. It is also a wrong approach for tackling performance issues.

You can listen to this latest episode either through the in-page player, by downloading the mp3 or subscribing to their feed. You can also page through his slides as you listen.