Engineers in Facebook anounced a new technology named HipHop to speed up the PHP processing and reduce the CPU/Memory load. Now about 90% web servers in Facebook have implemented HipHop and engineers have reduced the CPU usage on web servers on average by about fifty percent. The team leader of HipHop is Zhao Haiping (赵海平, BSc Beijing University, 1987 & Phd, Princeton).
“One of the key values at Facebook is to move fast. For the past six years, we have been able to accomplish a lot thanks to rapid pace of development that PHP offers. As a programming language, PHP is simple. Simple to learn, simple to write, simple to read, and simple to debug. We are able to get new engineers ramped up at Facebook a lot faster with PHP than with other languages, which allows us to innovate faster.
Today I’m excited to share the project a small team of amazing people and I have been working on for the past two years; HipHop for PHP. With HipHop we’ve reduced the CPU usage on our Web servers on average by about fifty percent, depending on the page. Less CPU means fewer servers, which means less overhead. This project has had a tremendous impact on Facebook. We feel the Web at large can benefit from HipHop, so we are releasing it as open source this evening in hope that it brings a new focus toward scaling large complex websites with PHP. While HipHop has shown us incredible results, it’s certainly not complete and you should be comfortable with beta software before trying it out.
HipHop for PHP isn’t technically a compiler itself. Rather it is a source code transformer. HipHop programmatically transforms your PHP source code into highly optimized C++ and then uses g++ to compile it. HipHop executes the source code in a semantically equivalent manner and sacrifices some rarely used features — such as eval() — in exchange for improved performance. HipHop includes a code transformer, a reimplementation of PHP’s runtime system, and a rewrite of many common PHP Extensions to take advantage of these performance optimizations.”
— HipHop for PHP: Move Fast, Haiping Zhao