Running a continuous integration process where you generate all your build artefacts on every build will push you to look for speed optimisations.
With an application I am currently configuring for Jenkins, it was taking about 30-35 minutes to generate all the API documentation through PHPDocumentor. I had heard good things about DocBlox - must notably its speed - and it's used by the Zend Framework so I thought I'd sub it in for PHPDocumentor and see if it was quicker.
DocBlox has a number of dependencies which we also need to install if they are not already.
Use your system's package manager to install the xsl php extension and graphviz.
$ sudo aptitude install php5-xsl $ sudo aptitude install graphviz
To install DocBlox and PHP-Markdown use PEAR.
$ sudo pear channel-discover pear.michelf.com $ sudo pear channel-discover pear.docblox-project.org $ sudo pear install --alldeps channel://pear.docblox-project.org/DocBlox-0.13.1
DocBlox uses largely the same command line options as phpdoc, so it can act as a drop in replacement if you already have existing build scripts utilising phpdoc.
In terms of speed, well, it's very fast. That 35 minute phpdoc run took just 43 seconds in DocBlox.