          # File lib/eventmachine.rb, line 1059
    1059:         def self.spawn_threadpool
    1060:           until @threadpool.size == 20
    1061:                         thread = Thread.new do
    1062:                                 while true
    1063:                                         op, cback = *@threadqueue.pop
    1064:                                         result = op.call
    1065:                                         @resultqueue << [result, cback]
    1066:                                         EventMachine.signal_loopbreak
    1067:                                 end
    1068:                         end
    1069:                         @threadpool << thread
    1070:                 end
    1071:         end