Inside Facebook

Earlier this morning, Facebook officially made their new PHP “compiler,” called HipHop, available as open source software. In the blog post by Haiping Zhao, HipHop for PHP is described as a “source code transformer” which has allowed Facebook to nearly double their PHP operating speeds, at the cost of minor omissions such rarely used functions in the PHP language. For a site which serves nearly 400 billion PHP-based page views every month, that is an incredible performance boost. According to the article, Facebook is now serving over 90% of their traffic using HipHop.

Essentially, HipHop for PHP gains its performance increase by transforming the scripted PHP language into the compiled C++ language. Scripted languages typically have the advantage of being simple to learn, code, and debug while sacrificing speed. Compiled languages on the other hand have a steeper learning curve and are more strict; however, are considerably faster and better optimized to handle memory. Facebook seems to have found a balance between both worlds with HipHop for PHP.

HipHop for PHP was accurately described in an old anonymous interview with a Facebook employee. Many of the details match up with information published in this morning’s blog post.

If you would like to learn for about HipHop, Facebook will be streaming a live tech talk regarding HipHop for PHP this evening at 7:30PM Pacific. You can watch live coverage of the event here. There is also a developer mailing list to which you can subscribe, and a HipHop wiki (the link has not yet been posted). All of the above details and more can also be found on the developer blog.