H2O is an optimized HTTP server implementation that can be used either as a standalone server or a library.
- 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)
- 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)
Written from the ground up, H2O outperforms nginx by more than 2x. The table below is a comparison of request-per-seconds taken using ab -c 500 -n 100000 -k on Ubuntu 14.04 running on VMWare Fusion.
| Server \ size of content | 6 bytes | 4,096 bytes |
|---|---|---|
| nginx/1.7.4 (conf) | 35,822 | 32,885 |
| H2O @ 6085457 | 76,690 | 67,866 |
Run the commands below to build and run the H2O server. The last command will read the configuration from examples/h2o.conf and start listening on port 8080. Try accessing http://127.0.0.1:8080/.
$ cmake .
$ make h2o
$ ./h2o -c examples/h2o.conf
$ 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.