base.rb

  def log(message)
    delayed_message = proc{"#{Time.now.strftime("%T.%L")} pid:#{Process.pid} cache_id:#{@cache_id} #{message}"}
    Rails.logger.error(" #{incr} #{delayed_message.()}")
    res = yield
    Rails.logger.error(" #{decr} #{delayed_message.()}")
    res
  end

  def incr
    @nesting ||= 0
    @nesting += 1
    "->" * @nesting
  end

  def decr
    @nesting -= 1
    "<-" * (@nesting + 1)
  end