child_runner is spawned more than 4 times

import gevent
import gevent.pool
import multiprocessing

def child_runner():
    p = multiprocessing.Process(target=child)
    p.start()
    print gevent.getcurrent()

def child():
    gevent.sleep(1)

if __name__ == "__main__":
    p = gevent.pool.Pool(size=16)
    p.spawn(child_runner)
    p.spawn(child_runner)
    p.spawn(child_runner)
    p.spawn(child_runner)
    p.join()