Passenger restart task in Capistrano 3.x with Rails 4.x

passenger.rake

namespace :deploy do
  after :restart, :restart_passenger do
    on roles(:web), in: :groups, limit: 3, wait: 10 do
      within release_path do
        execute :touch, 'tmp/restart.txt'
      end
    end
  end
  after :finishing, 'deploy:restart_passenger'
end