yahns – Sleepy, multi-threaded, non-blocking application server for Ruby

yahns is a multi-threaded, non-blocking network application server designed for low _idle_ power consumption.

It is primarily optimized for applications with occasional users which see little or no traffic.
yahns currently hosts Rack/HTTP applications, but may eventually support other application types. Unlike some existing servers, yahns is extremely sensitive to fatal bugs in the applications it hosts.

This is free and open source software.

  • _zero_ wakeups when all clients are idle.
  • Idle client connections may live forever if there is no FD pressure.
  • Suitable for slow clients, fast clients, or a mixture of both.
  • HTTP/0.9 support.
  • HTTP/1.1 persistent connections and pipelining.
  • HTTPS for HTTP/1.1 support.
  • Decodes HTTP chunked encoding for requests.
  • Parses HTTP/1.1 trailers in requests.
  • Supports streaming responses with lazy buffering for slow clients.
  • Optional streaming input for fast clients.
  • Host multiple applications with different settings.
  • Uses epoll/kqueue to scale to many idle connections.
  • Abuses epoll/kqueue as a load balancer between threads within a process.
  • Optional multi-process support (in addition to threads).
  • Fairly balances new clients between multiple processes (on Linux).

Website: yhbt.net/yahns
Developer: yahns contributors
License: GPL-3.0+

yahns is written in Ruby. Learn Ruby with our recommended free books and free tutorials.

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