Rake task for Delayed::Job to launch multiple monitored workers in a container context

delayed_job.rake

namespace :jobs do
  desc "Start one or more monitored delayed_job workers (as per environment)"
  task :workmulti => :environment do
    daemons_count = Rails.env.production? ? 5 : 1
    pids = []
    loop do
      pids.delete_if { !(Process.kill(0, _1) rescue false) }
      (daemons_count - pids.count).times do
        pids << fork { Delayed::Worker.new.start }
        Process.detach pids.last
      end
      sleep 60
    end
  ensure
    pids.each { Process.kill('TERM', _1) }
  end
end