Class: Forklift::Master

Inherits:
Object
  • Object
show all
Defined in:
lib/forklift/master.rb,
lib/forklift/master_old.rb

Constant Summary collapse

WORKERS =

This hash maps PIDs to Workers

{}
SELF_PIPE = 
[]
SIG_QUEUE =

signal queue used for self-piping

[]
QUEUE_SIGS =

list of signals we care about and trap in master.

[ :WINCH, :QUIT, :INT, :TERM, :USR1, :USR2, :HUP, :TTIN, :TTOU ]
START_CTX = 
{
  :argv => ARGV.map { |arg| arg.dup },
  0 => $0.dup,
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Master

Returns a new instance of Master.



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# File 'lib/forklift/master.rb', line 35

def initialize
  self.reexec_pid = 0
  self.worker_processes = 2
  @logger = Logger.new($stdout)
  @timeout = 100
end

Instance Attribute Details

#after_fork ⇒ Object

Returns the value of attribute after_fork.



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# File 'lib/forklift/master_old.rb', line 5

def after_fork
  @after_fork
end

#app ⇒ Object

Returns the value of attribute app.



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# File 'lib/forklift/master_old.rb', line 5

def app
  @app
end

#before_exec ⇒ Object

Returns the value of attribute before_exec.



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# File 'lib/forklift/master_old.rb', line 5

def before_exec
  @before_exec
end

#before_fork ⇒ Object

Returns the value of attribute before_fork.



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# File 'lib/forklift/master_old.rb', line 5

def before_fork
  @before_fork
end

#config ⇒ Object

Returns the value of attribute config.



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# File 'lib/forklift/master_old.rb', line 5

def config
  @config
end

#init_listeners ⇒ Object

Returns the value of attribute init_listeners.



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# File 'lib/forklift/master_old.rb', line 5

def init_listeners
  @init_listeners
end

#listener_opts ⇒ Object

Returns the value of attribute listener_opts.



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# File 'lib/forklift/master_old.rb', line 5

def listener_opts
  @listener_opts
end

#logger ⇒ Object (readonly)

Returns the value of attribute logger.



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# File 'lib/forklift/master.rb', line 10

def logger
  @logger
end

#master_pid ⇒ Object

Returns the value of attribute master_pid.



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# File 'lib/forklift/master.rb', line 11

def master_pid
  @master_pid
end

#orig_app ⇒ Object

Returns the value of attribute orig_app.



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# File 'lib/forklift/master_old.rb', line 5

def orig_app
  @orig_app
end

#pid ⇒ Object (readonly)

Returns the value of attribute pid.



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# File 'lib/forklift/master.rb', line 10

def pid
  @pid
end

#preload_app ⇒ Object

Returns the value of attribute preload_app.



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# File 'lib/forklift/master_old.rb', line 5

def preload_app
  @preload_app
end

#ready_pipe ⇒ Object

Returns the value of attribute ready_pipe.



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# File 'lib/forklift/master_old.rb', line 5

def ready_pipe
  @ready_pipe
end

#reexec_pid ⇒ Object

Returns the value of attribute reexec_pid.



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# File 'lib/forklift/master.rb', line 11

def reexec_pid
  @reexec_pid
end

#timeout ⇒ Object

Returns the value of attribute timeout.



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# File 'lib/forklift/master.rb', line 11

def timeout
  @timeout
end

#user ⇒ Object

Returns the value of attribute user.



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# File 'lib/forklift/master_old.rb', line 5

def user
  @user
end

#worker_processes ⇒ Object

Returns the value of attribute worker_processes.



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# File 'lib/forklift/master.rb', line 11

def worker_processes
  @worker_processes
end

Instance Method Details

#join ⇒ Object

monitors children and receives signals forever (or until a termination signal is sent). This handles signals one-at-a-time time and we’ll happily drop signals in case somebody is signalling us too often.



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# File 'lib/forklift/master_old.rb', line 71

def join
  respawn = true
  last_check = Time.now

  proc_name 'master'
  logger.info "master process ready" # test_exec.rb relies on this message
  if @ready_pipe
    @ready_pipe.syswrite($$.to_s)
    @ready_pipe = @ready_pipe.close rescue nil
  end

  begin
    reap_all_workers

    case SIG_QUEUE.shift
    when nil
      # avoid murdering workers after our master process (or the
      # machine) comes out of suspend/hibernation
      if (last_check + @timeout) >= (last_check = Time.now)
        sleep_time = murder_lazy_workers
      else
        sleep_time = @timeout/2.0 + 1
        @logger.debug("waiting #{sleep_time}s after suspend/hibernation")
      end
      maintain_worker_count if respawn
      master_sleep(sleep_time)

    when :QUIT # graceful shutdown
      break
    when :TERM, :INT # immediate shutdown
      stop(false)
      break
    when :USR1 # rotate logs
      logger.info "master done reopening logs"
      kill_each_worker(:USR1)
    when :USR2 # exec binary, stay alive in case something went wrong
      # reexec
    end

  rescue => e
    Forklift.log_error(@logger, "master loop error", e)
  end while true

  stop # gracefully shutdown all workers on our way out
  logger.info "master complete"
  unlink_pid_safe(pid) if pid
end

#start ⇒ Object 



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# File 'lib/forklift/master.rb', line 42

def start
  init_self_pipe!
  # setup signal handlers before writing pid file in case people get
  # trigger happy and send signals as soon as the pid file exists.
  # Note that signals don't actually get handled until the #join method
  QUEUE_SIGS.each { |sig| trap(sig) { SIG_QUEUE << sig; awaken_master } }
  trap(:CHLD) { awaken_master }

  self.master_pid = $$

  logger.info "Starting master"

  spawn_missing_workers

  self
end