class Roundhouse::ProcessSet

Enumerates the set of Roundhouse processes which are actively working right now. Each process send a heartbeat to Redis every 5 seconds so this set should be relatively accurate, barring network partitions.

Yields a Roundhouse::Process.

Public Class Methods

cleanup() click to toggle source

Cleans up dead processes recorded in Redis. Returns the number of processes cleaned.

# File lib/roundhouse/api.rb, line 686
def self.cleanup
  count = 0
  Roundhouse.redis do |conn|
    procs = conn.smembers('processes').sort
    heartbeats = conn.pipelined do
      procs.each do |key|
        conn.hget(key, 'info')
      end
    end

    # the hash named key has an expiry of 60 seconds.
    # if it's not found, that means the process has not reported
    # in to Redis and probably died.
    to_prune = []
    heartbeats.each_with_index do |beat, i|
      to_prune << procs[i] if beat.nil?
    end
    count = conn.srem('processes', to_prune) unless to_prune.empty?
  end
  count
end
new(clean_plz=true) click to toggle source
# File lib/roundhouse/api.rb, line 680
def initialize(clean_plz=true)
  self.class.cleanup if clean_plz
end

Public Instance Methods

each() { |process(merge('busy' => to_i, 'beat' => to_f))| ... } click to toggle source
# File lib/roundhouse/api.rb, line 708
def each
  procs = Roundhouse.redis { |conn| conn.smembers('processes') }.sort

  Roundhouse.redis do |conn|
    # We're making a tradeoff here between consuming more memory instead of
    # making more roundtrips to Redis, but if you have hundreds or thousands of workers,
    # you'll be happier this way
    result = conn.pipelined do
      procs.each do |key|
        conn.hmget(key, 'info', 'busy', 'beat')
      end
    end

    result.each do |info, busy, at_s|
      hash = Roundhouse.load_json(info)
      yield Process.new(hash.merge('busy' => busy.to_i, 'beat' => at_s.to_f))
    end
  end

  nil
end
size() click to toggle source

This method is not guaranteed accurate since it does not prune the set based on current heartbeat. each does that and ensures the set only contains Roundhouse processes which have sent a heartbeat within the last 60 seconds.

# File lib/roundhouse/api.rb, line 734
def size
  Roundhouse.redis { |conn| conn.scard('processes') }
end