Question

Facebook just open-sourced a framework called Tornado.

What is it? What does it help a site do?

I believe Facebook uses a LAMP structure. Is it useful for smaller sites which are written under the LAMP stack?

Answer 1

It looks like it is a web-server optimized for high-concurrency and high-scalability, but made for smaller payloads.

It was designed to support 10,000 concurrent users well.

The framework is distinct from most
mainstream web server frameworks (and
certainly most Python frameworks)
because it is non-blocking and
reasonably fast. Because it is
non-blocking and uses epoll, it can
handle thousands of simultaneous
standing connections, which means it
is ideal for real-time web services.
We built the web server specifically
to handle FriendFeed’s real-time
features — every active user of
FriendFeed maintains an open
connection to the FriendFeed servers.
(For more information on scaling
servers to support thousands of
clients, see The C10K problem.)

It will run on a LMP stack, but it takes the place of Apache.

See the C10K problem.