Reel

Build Status

Reel is a fast, non-blocking "evented" web server built on http_parser.rb, Celluloid::IO, and nio4r. It's probably most similar to Goliath, but thanks to Celluloid also works great for multithreaded applications and provides traditional multithreaded blocking I/O support too.

Connections to Reel can be either non-blocking and handled entirely within the Reel::Server thread, or the same connections can be dispatched to worker threads where they will perform ordinary blocking IO. Reel provides no built-in thread pool, however you can build one yourself using Celluloid::Pool, or because Celluloid already pools threads to begin with, you can simply use an actor per connection.

This gives you the best of both worlds: non-blocking I/O for when you're primarily I/O bound, and threads for where you're compute bound.

Is It Good?

Yes, but it has room for improvement. A "hello world" web server benchmark, run on a 2GHz i7 (OS X 10.7.3). All servers used in a single-threaded mode.

Reel performance on various Ruby VMs:

# httperf --num-conns=50 --num-calls=1000

Ruby Version        Throughput    Latency
------------        ----------    -------
JRuby HEAD          5650 reqs/s   (0.2 ms/req)
Ruby 1.9.3          5263 reqs/s   (0.2 ms/req)
JRuby 1.6.7         4303 reqs/s   (0.2 ms/req)
rbx HEAD            2288 reqs/s   (0.4 ms/req)

Comparison with other web servers:

Web Server          Throughput    Latency
----------          ----------    -------
Goliath (0.9.4)     2058 reqs/s   (0.5 ms/req)
Thin    (1.2.11)    7502 reqs/s   (0.1 ms/req)
Node.js (0.6.5)     11735 reqs/s  (0.1 ms/req)

All Ruby benchmarks done on Ruby 1.9.3. Latencies given are average-per-request and are not amortized across all concurrent requests.

Usage

Reel provides an extremely simple API:

require 'reel'

Reel::Server.supervise("0.0.0.0", 3000) do |connection|
  request = connection.request
  puts "Client requested: #{request.method} #{request.url}"
  connection.respond :ok, "hello, world"
end

Status

Reel is still in an extremely early stage of development and may be missing a lot of features. It seems to be doing a rudimentary job of speaking HTTP and has basic keep-alive support.

Contributing

  • Fork this repository on github
  • Make your changes and send me a pull request
  • If I like them I'll merge them
  • If I've accepted a patch, feel free to ask for commit access

License

Copyright (c) 2012 Tony Arcieri. Distributed under the MIT License. See LICENSE.txt for further details.