          # File lib/eventmachine.rb, line 1059
    1059:   def self.defer op = nil, callback = nil, &blk
    1060:     unless @threadpool
    1061:       require 'thread'
    1062:       @threadpool = []
    1063:       @threadqueue = ::Queue.new
    1064:       @resultqueue = ::Queue.new
    1065:       spawn_threadpool
    1066:     end
    1067:
    1068:     @threadqueue << [op||blk,callback]
    1069:   end