Interesting. Design. Scaling. Wsgi. Lionet: Erlang, Yaws, and the deadly Tornado. Good things sometimes happen to the open source community. Since Facebook acquisition of FriendFeed, a bunch of technologies were released to the wild, including, most notably, a Tornado web server written in Python. The Tornado is touted as a «a scalable, non-blocking web server and web framework».
See Wikipedia article on some details on the performance of that server, as well as some comparison with other web servers. Here's the chart, taken from Wikipedia: The numbers looked interesting, so I decided to benchmark Tornado myself to check out how it fares against some Erlang tools. Keep in mind that Erlang runtime itself is not the fastest beast in the woods. It is generally considered slower than many other interpreted languages (including Python), especially on file operations (due to complexities of the io library doing most of heavy lifting). There are a few web servers for Erlang VM, notably Yaws and Mochiweb. So, meet Yucan. Beautiful Word Clouds.