[ANN] unicorn 6.1.0 - Rack HTTP server for fast clients and *nix

[Eric Wong <e@80x24.org>]

unicorn is an HTTP server for Rack applications designed to only serve
fast clients on low-latency, high-bandwidth connections and take
advantage of features in Unix/Unix-like kernels.  Slow clients should
only be served by placing a reverse proxy capable of fully buffering
both the the request and response in between unicorn and slow clients.

Disclaimer:

Due to its ability to tolerate crashes and isolate clients, unicorn
is unfortunately known to prolong the existence of bugs in applications
and libraries which run on top of it.

Consider this just an announcement to inform existing users of a
new version, not something to convince you to switch to something
that set the entire Ruby world back decades in terms of concurrency.

Note:
.onion URLs below are available for Tor users and can reduce
our operating costs:

* https://yhbt.net/unicorn/
  http://unicorn.7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/
* public list: unicorn-public@yhbt.net
* mail archives: https://yhbt.net/unicorn-public/
  http://7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/unicorn-public/
* git clone https://yhbt.net/unicorn.git
  torsocks git clone http://7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/unicorn.git
* https://yhbt.net/unicorn/NEWS.atom.xml
  http://unicorn.7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/NEWS.atom.xml
* nntps://news.public-inbox.org/inbox.comp.lang.ruby.unicorn
  nntp://7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/inbox.comp.lang.ruby.unicorn
  imaps://yhbt.net/inbox.comp.lang.ruby.unicorn.0
  imap://7fh6tueqddpjyxjmgtdiueylzoqt6pt7hec3pukyptlmohoowvhde4yd.onion/inbox.comp.lang.ruby.unicorn.0

Changes:

    This release reduces CPU usage for Linux 4.5+ in most cases.
    See "[PATCH 6/6] use EPOLLEXCLUSIVE on Linux 4.5+" for more details:
      https://yhbt.net/unicorn-public/20211001030923.26705-7-bofh@yhbt.net/

    There's a couple of updates for Ruby 3.1, but we've finally
    started relying on Ruby 2.0.0 features after 9 years :P
    (so Ruby 1.9.3 users are stuck with older versions).

    And the usual round of doc updates and some build speedups.

    13 changes by the Bozo Doofus maintainer since v6.0.0:

          test_util: less excessive encoding tests
          drop Ruby 1.9.3 support, require 2.0+ for now
          drop unnecessary IO#close_on_exec=true assignment
          extconf.rb: get rid of unnecessary checks
          makefile: reduce unnecessary rebuilds
          HACKING: drop outdated information about pandoc
          http_server: get rid of Process.ppid check
          worker_loop: get rid of select() avoidance hack
          use EPOLLEXCLUSIVE on Linux 4.5+
          allow Ruby to deduplicate remaining globals
          epollexclusive: remove rb_gc_force_recycle call
          drop Ruby version warning, fix speling errer
          doc: v3 .onion updates, nntp => nntps, minor wording changes