Rails: slow query logging instrumentation

x.rb

ActiveSupport::Notifications.subscribe("sql.active_record") do |_name, start, finish, _id, payload|
  duration = finish.to_f - start.to_f
  if duration >= 1.0 # Feel free to change
    Rails.logger.warn "slow query detected: #{payload[:sql]}, duration: #{duration}"
    caller.each do |line|
      next unless line.include? Dir.pwd
      Rails.logger.warn line
    end
  end
end