H2O - an optimized HTTP server / library implementation

H2O is an optimized HTTP server implementation that can be used either as a standalone server or a library.

Supported Protocols

HTTP/1.0 (http and https)
HTTP/1.1 (http and https)
Websocket (RFC6455, both ws and wss)
HTTP/2.0 (draft 14, via Upgrade, NPN, ALPN)

Dependencies

OpenSSL (mandatory)
libyaml (optional; required when building the server)
libuv 1.0.0 (optional; required when using h2o as a library)
wslay (optional; required if you need support for websocket)

note: Older versions of libuv cannot be used due to massive API changes in libuv 1.0. Please use the latest RC of libuv 1.0.

Building and Running the Server

Run the commands below to build and run the H2O server. The last command will read the configuration from examples/h2o/h2o.conf and start listening on port 8080. Try accessing http://127.0.0.1:8080/.

$ git submodule update --init --recursive
$ cmake .
$ make h2o
$ ./h2o -c examples/h2o/h2o.conf

Use --help to print the list of configuration directives available.

$ ./h2o --help

Building the Library

$ git submodule update --init --recursive
$ cmake .
$ make libh2o

The library is designed to work together with the upcoming libuv version 1.0.0. Examples can be found within the examples/ directory.

Benchmarks

HTTP/1.1

Server \ size of content	6 bytes	4,096 bytes
nginx/1.7.4 (conf)	45,866	47,579
H2O @ eef1612	73,800	63,768

note: wrk -c 500 -d 30 -t 1 on Ubuntu 14.04 on VMWare Fusion

HTTP/2

Server \ size of content	6 bytes	4,096 bytes
tiny-nghttpd (nghttpd @ 9c0760e)	146,506	77,352
trusterd @ 962d031	125,482	50,103
H2O @ 7505a82	201,077	90,810