unicorn.rb

APP_PATH = File.expand_path('../..', __FILE__)
require File.join(APP_PATH, "lib/site")

working_directory APP_PATH

pid_path = File.join(APP_PATH, "tmp/pids/web.pid")
pid pid_path

stderr_path File.join(APP_PATH, "log/unicorn-stderr")
stdout_path File.join(APP_PATH, "log/unicorn-stdout")

worker_processes ENV['RAILS_ENV'] == 'production' ? 4 : 1
listen Site.current.http_port, :tcp_nopush => true

preload_app true

before_fork do |server, worker|
  ActiveRecord::Base.connection.disconnect! if defined?(ActiveRecord::Base)

  ENV['BUNDLE_GEMFILE'] = File.join(APP_PATH, "Gemfile")

  old_pid_file = "#{pid_path}.oldbin"
  old_pid = File.exists?(old_pid_file) && File.read(old_pid_file).to_i
  if old_pid && server.pid != old_pid
    puts "Killing old unicorn with PID #{old_pid}..."
    begin
      Process.kill("QUIT", old_pid)
    rescue Errno::ENOENT, Errno::ESRCH
      # someone else did our job for us
    end
  end
end

after_fork do |server, worker|
  ActiveRecord::Base.establish_connection if defined?(ActiveRecord::Base)
end

Thanks! Just what i needed :)