ruby God monitor process

god.md

如果god用到新的gem,需要重启god

help

god -h

config

god -c config/god/resque.god

load

god load config/god/resque.god # if god has running, u can do this

status

god status

restart

god restart resque

stop

god stop resque

start

god start resque

resque.rb

# https://github.com/defunkt/resque/blob/master/examples/god/resque.god
# https://github.com/muik/resque-rails-god-example/blob/master/config/resque.god

rails_env   = ENV['RAILS_ENV']  || "production"
rails_root  = ENV['RAILS_ROOT'] || "/data/projects/entos/current"
num_workers = rails_env == 'production' ? 5 : 2

num_workers.times do |num|
  God.watch do |w|
    w.dir      = "#{rails_root}"
    w.name     = "resque-#{num}"
    w.group    = 'resque'
    w.interval = 30.seconds
    w.env      = if rails_env == 'production'
      {"QUEUE"=>"*", "RAILS_ENV"=>rails_env}
    else
      {"QUEUE"=>"*", "RAILS_ENV"=>rails_env, 'VVERBOSE'=>1}
    end
    w.start    = "bundle exec rake -f #{rails_root}/Rakefile environment resque:work"
    w.log      = "#{rails_root}/log/resque.log"
    w.err_log  = "#{rails_root}/log/resque_error.log"

    # w.uid = 'root'
    # w.gid = 'root'

    # restart 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
end