[ANN] unicorn 5.3.0.pre1 - Rack HTTP server for fast clients and Unix

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.

* https://bogomips.org/unicorn/
* public list: unicorn-public@bogomips.org
* mail archives: https://bogomips.org/unicorn-public/
* git clone git://bogomips.org/unicorn.git
* https://bogomips.org/unicorn/NEWS.atom.xml
* nntp://news.public-inbox.org/inbox.comp.lang.ruby.unicorn

This is a pre-release RubyGem intended for testing.

Changes:

unicorn 5.3.0.pre1

A largish release with several new features.

Simon Eskildsen contributed heavily using TCP_INFO under Linux
to implement the (now 5 year old) check_client_connection feature:

  https://bogomips.org/unicorn/Unicorn/Configurator.html#method-i-check_client_connection
  https://bogomips.org/unicorn-public/?q=s:check_client_connection&d:..20170324&x=t

This also led to FreeBSD and OpenBSD portability improvements in
one of our dependencies, raindrops:

  https://bogomips.org/raindrops-public/20170323024829.GA5190@dcvr/T/#u

Jeremy Evans contributed several new features. First he
implemented after_worker_exit to aid debugging:

  https://bogomips.org/unicorn/Unicorn/Configurator.html#method-i-after_worker_exit
  https://bogomips.org/unicorn-public/?q=s:after_worker_exit&d:..20170324&x=t#t

And then security-related features to isolate workers. Workers
may now chroot to drop access to the master filesystem, and the
new after_worker_ready configuration hook now exists to aid with
chroot support in workers:

  https://bogomips.org/unicorn/Unicorn/Configurator.html#method-i-after_worker_ready
  https://bogomips.org/unicorn/Unicorn/Worker.html#method-i-user
  https://bogomips.org/unicorn-public/?q=s:after_worker_ready&d:..20170324&x=t#t
  https://bogomips.org/unicorn-public/?q=s:chroot&d:..20170324&x=t#t

Additionally, workers may run in a completely different VM space
(nullifying preload_app and any CoW savings) with the new
worker_exec option:

  https://bogomips.org/unicorn/Unicorn/Configurator.html#method-i-worker_exec
  https://bogomips.org/unicorn-public/?q=s:worker_exec&d:..20170324&x=t#t

There are also several improvements to FreeBSD and OpenBSD
support with the addition of these features.

34 changes since 5.2.0 (2016-10-31):

Eric Wong (27):
      drop rb_str_set_len compatibility replacement
      TUNING: document THP caveat for Linux users
      tee_input: simplify condition for IO#write
      remove response_start_sent
      http_request: freeze constant strings passed IO#write
      Revert "remove response_start_sent"
      t/t0012-reload-empty-config.sh: access ivars directly if needed
      t0011-active-unix-socket.sh: fix race condition in test
      new test for check_client_connection
      revert signature change to HttpServer#process_client
      support "struct tcp_info" on non-Linux and Ruby 2.2+
      unicorn_http: reduce rb_global_variable calls
      oob_gc: rely on opt_aref_with optimization on Ruby 2.2+
      http_request: reduce insn size for check_client_connection
      freebsd: avoid EINVAL when setting accept filter
      test-lib: expr(1) portability fix
      tests: keep disabled tests defined
      test_exec: SO_KEEPALIVE value only needs to be true
      doc: fix links to raindrops project
      http_request: support proposed Raindrops::TCP states on non-Linux
      ISSUES: expand on mail archive info + subscription disclaimer
      test_ccc: use a pipe to synchronize test
      doc: remove private email support address
      input: update documentation and hide internals.
      http_server: initialize @pid ivar
      gemspec: remove olddoc from build dependency
      doc: add version annotations for new features

Jeremy Evans (6):
      Add after_worker_exit configuration option
      Fix code example in after_worker_exit documentation
      Add support for chroot to Worker#user
      Add after_worker_ready configuration option
      Add worker_exec configuration option
      Don't pass a block for fork when forking workers

Simon Eskildsen (1):
      check_client_connection: use tcp state on linux

···

--
5.3.0 in a week, maybe?