em_mysql2

gistfile1.rb

gem 'activerecord', '3.1.1'
gem 'mysql2', '~> 0.3.0'
gem 'em-synchrony', '1.0.0'

require 'logger'
require 'fiber'

require 'active_record'
require 'mysql2'
require 'eventmachine'
require 'em-synchrony'
require 'em-synchrony/activerecord'

ActiveRecord::Base.logger = Logger.new($stdout)

ActiveRecord::Base.establish_connection(
  :adapter => 'em_mysql2',
  :database => "test",
  :username => "root",
  :pool => 1
)

def log(msg)
  t = Time.now.strftime("%H:%M:%S")
  puts("[#{t}] #{msg}")
end

def get_time
  Time.now.to_f * 1000
end

def do_job
  log "[#{'%x' % Fiber.current.object_id}] Waiting"
  started_at = get_time()
  ActiveRecord::Base.connection_pool.with_connection do |conn|
    working_at = get_time()
    log "[#{'%x' % Fiber.current.object_id}] Working with (#{'%x' % conn.object_id})"
    ActiveRecord::Base.connection.execute("SELECT SLEEP(1)")
    now = get_time()
    log "[#{'%x' % Fiber.current.object_id}] Done (wait: #{(working_at - started_at).to_i}ms, execution: #{(now - working_at).to_i}ms)"
  end
end

DELAY = 0

EM::run do
  5.times do |n|
    EM::add_timer(n * DELAY) do
      Fiber.new{ do_job() }.resume
    end
  end
end