unicornの導入

Rakefile.tmp

namespace :unicorn do

  ##
  # Tasks

  desc "Start unicorn"
  task(:start) {
    config = rails_root + "config/unicorn.rb"
    env = ENV['RAILS_ENV'] || "development"
    sh "bundle exec unicorn_rails -D -c #{config} -E #{env}"
  }

  desc "Stop unicorn"
  task(:stop) { unicorn_signal :QUIT }

  desc "Restart unicorn with USR2"
  task(:restart) { unicorn_signal :USR2 }

  desc "Increment number of worker processes"
  task(:increment) { unicorn_signal :TTIN }

  desc "Decrement number of worker processes"
  task(:decrement) { unicorn_signal :TTOU }

  desc "Unicorn pstree (depends on pstree command)"
  task(:pstree) do
    sh "pstree '#{unicorn_pid}'"
  end

  ##
  # Helpers

  def unicorn_signal signal
    Process.kill signal, unicorn_pid
  end

  def unicorn_pid
    begin
      File.read(rails_root + "tmp/pids/unicorn.pid").to_i
    rescue Errno::ENOENT
      raise "Unicorn doesn't seem to be running"
    end
  end

  def rails_root
    require "pathname"
    Pathname.new(__FILE__) + "../"
  end

end

unicorn.rb

worker_processes Integer(ENV["WEB_CONCURRENCY"] || 3) # 子プロセスいくつ立ち上げるか
timeout 15 #15秒Railsが反応しなければWorkerをkillしてタイムアウト
preload_app true #後述

# 同一マシンでNginxとプロキシ組むならsocketのが高速ぽい(後述ベンチ)
# listen /path/to/rails/tmp/unicorn.sock
listen 3000

# pid file path Capistranoとか使う時は要設定か
# pid /path/to/rails/tmp/pids/unicorn.pid

# ログの設定方法.
#stderr_path File.expand_path('log/unicorn.log', ENV['RAILS_ROOT'])
#stdout_path File.expand_path('log/unicorn.log', ENV['RAILS_ROOT'])

before_fork do |server, worker|
  old_pid = "#{ server.config[:pid] }.oldbin"
  if File.exists?(old_pid) && server.pid != old_pid
    begin
      # 古いマスターがいたら死んでもらう
      Process.kill("QUIT", File.read(old_pid).to_i)
    rescue Errno::ENOENT, Errno::ESRCH
      # someone else did our job for us
    end
  end

  defined?(ActiveRecord::Base) and
    ActiveRecord::Base.connection.disconnect!
end 

after_fork do |server, worker|
  Signal.trap 'TERM' do
    puts 'Unicorn worker intercepting TERM and doing nothing. Wait for master to send QUIT'
  end

  defined?(ActiveRecord::Base) and
    ActiveRecord::Base.establish_connection
end

def rails_root
  require "pathname"
  Pathname.new(__FILE__) + "../../"
end