rosa-build/config/unicorn.rb

#base_path = File.expand_path(File.join File.dirname(__FILE__), '..')
base_path  = "/srv/rosa_build"

rails_env = ENV['RAILS_ENV'] || 'production'

worker_processes 8
working_directory File.join(base_path, 'current') # available in 0.94.0+

# listen File.join(base_path, 'tmp', 'pids', 'unicorn.sock')
# listen "/tmp/.sock", backlog: 64
# listen 8080, tcp_nopush: true

# nuke workers after 30 seconds instead of 60 seconds (the default)
timeout 600

# feel free to point this anywhere accessible on the filesystem
pid_file = File.join(base_path, 'shared', 'pids', 'unicorn.pid')
old_pid = pid_file + '.oldbin'

pid pid_file

# REE or Ruby 2.0
# http://www.rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
GC.copy_on_write_friendly = true if GC.respond_to?(:copy_on_write_friendly=)

before_exec do |server|
  ENV["BUNDLE_GEMFILE"] = "#{base_path}/current/Gemfile"
end

# By default, the Unicorn logger will write to stderr.
# Additionally, ome applications/frameworks log to stderr or stdout,
# so prevent them from going to /dev/null when daemonized here:
stderr_path File.join(base_path, 'current', 'log', 'unicorn.stderr.log')
stdout_path File.join(base_path, 'current', 'log', 'unicorn.stdout.log')

# combine REE with "preload_app true" for memory savings
# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
preload_app true

before_fork do |server, worker|
  # This option works in together with preload_app true setting
  # What is does is prevent the master process from holding
  # the database connection
  defined?(ActiveRecord::Base) and ActiveRecord::Base.connection.disconnect!

  # When sent a USR2, Unicorn will suffix its pidfile with .oldbin and
  # immediately start loading up a new version of itself (loaded with a new
  # version of our app). When this new Unicorn is completely loaded
  # it will begin spawning workers. The first worker spawned will check to
  # see if an .oldbin pidfile exists. If so, this means we've just booted up
  # a new Unicorn and need to tell the old one that it can now die. To do so
  # we send it a QUIT.
  #
  # Using this method we get 0 downtime deploys.

  if File.exists?(old_pid) && server.pid != old_pid
    begin
      Process.kill("QUIT", File.read(old_pid).to_i)
    rescue Errno::ENOENT, Errno::ESRCH
      # someone else did our job for us
    end
  end
end

after_fork do |server, worker|
  # Here we are establishing the connection after forking worker processes
  defined?(ActiveRecord::Base) and ActiveRecord::Base.establish_connection

  # if preload_app is true, then you may also want to check and
  # restart any other shared sockets/descriptors such as Memcached,
  # and Redis.  TokyoCabinet file handles are safe to reuse
  # between any number of forked children (assuming your kernel
  # correctly implements pread()/pwrite() system calls)
  # srand
end