monitor-redis-resque.rb

# Redis
%w{6379}.each do |port|
  God.watch do |w|
    w.name          = "redis"
    w.interval      = 30.seconds
    w.start         = "/etc/init.d/redis start"
    w.stop          = "/etc/init.d/redis stop"
    w.restart       = "/etc/init.d/redis restart"
    w.start_grace   = 10.seconds
    w.restart_grace = 10.seconds

    w.start_if do |start|
      start.condition(:process_running) do |c|
          c.interval = 5.seconds
          c.running = false
      end
    end
  end
end

# Resque
God.watch do |w|
  w.name          = "resque-1.8.0"
  w.interval      = 30.seconds
  w.start         = "cd /var/www/apps/limitedpressing/current && rake environment RAILS_ENV=production resque:work QUEUE=high,medium,low"
  w.start_grace   = 10.seconds
  
  # retart if memory gets too high
  w.transition(:up, :restart) do |on|
    on.condition(:memory_usage) do |c|
      c.above = 350.megabytes
      c.times = 2
    end
  end
  
  # determine the state on startup
  w.transition(:init, { true => :up, false => :start }) do |on|
    on.condition(:process_running) do |c|
      c.running = true
    end
  end
  
  # determine when process has finished starting
  w.transition([:start, :restart], :up) do |on|
    on.condition(:process_running) do |c|
      c.running = true
      c.interval = 5.seconds
    end
    
    # failsafe
    on.condition(:tries) do |c|
      c.times = 5
      c.transition = :start
      c.interval = 5.seconds
    end
  end
  
  # start if process is not running
  w.transition(:up, :start) do |on|
    on.condition(:process_running) do |c|
      c.running = false
    end
  end
end

(sorry I posted with the wrong account earlier).

I was using your /etc/init.d/redis script -- which daemonizes redis. Just adding a block with redis's pid file fixes the problem.

w.pid_file = '/var/run/redis.pid'
w.behavior(:clean_pid_file)

thanks

Ahhh, I apologize. I thought you were talking about resque restarting. Very odd, I don't have any issue with redis continually being started by god with this setup, but thanks for the update!

no the problem isn't redis restarting. it's god continually trying to restart redis (while it's running happily). check your /var/run/god/redis.pid and see if it matches the redis-server's actual pid.

Okay, I totally misunderstood, sorry. I had a problem where god would keep starting new resque workers so I thought you were talking about that.

You're right, the pid is wrong and also my /etc/init.d/redis script is creating a pid at /var/run/redis.pid whereas god is using /var/run/god/redis.pid. Everything's all confused haha.

So I guess the God.watch can be moved out the of the useless port loop, like you mentioned earlier. Then those two lines you added above: w.pid_file and w.behavior, can those be added within the God.watch block?

checkout my fork, it has my changes. but the answer is: yes :)

p.s. thanks for the blogpost regardless. was useful for getting started. truth be told, I think god docs are lacking.

Awesome. Thanks for the fork. I'll pull in your changes and update my post. And no problem, I mostly had a problem figuring out how to get the resque workers to get restarted on deploy though. That was a real pain in the ass for me. Thanks again!