using tornado ioloop in multiple threads

app.py

import random
import threading
import time

import tornado.gen
import tornado.ioloop


@tornado.gen.coroutine
def _work(i):
    count = random.randint(1, 10)
    print("Thread {} count: {}".format(i, count))

    for _ in range(count):
        print("Thread {} working...".format(i))
        yield tornado.gen.sleep(0.1)

    ioloop = tornado.ioloop.IOLoop().current()
    print("Thread {} ident: {}".format(i, threading.get_ident()))

    ioloop.stop()
    print("Thread {} done.".format(i))


def work(i):
    ioloop = tornado.ioloop.IOLoop().current()
    print("Thread {} ident: {}".format(i, threading.get_ident()))

    _work(i)

    ioloop.start()
    print(i, ioloop)


def main():
    workers = []
    for i in range(3):
        worker = threading.Thread(target=work, args=(i,))
        worker.setDaemon(True)
        workers.append(worker)
    for worker in workers:
        worker.start()
    for worker in workers:
        worker.join()


if __name__ == '__main__':
    main()

archlinux-python3.6.5-tornado4.5.3-result.txt

$ python3 app.py 
Thread 2 ident: 140376056444672
Thread 2 count: 1
Thread 2 working...
Thread 0 ident: 140376073230080
Thread 1 ident: 140376064837376
Thread 0 count: 7
Thread 1 count: 6
Thread 0 working...
Thread 1 working...
Thread 1 working...
Thread 0 working...
Thread 2 ident: 140376056444672
Thread 2 done.
2 <tornado.platform.epoll.EPollIOLoop object at 0x7fabdb69fc50>
Thread 1 working...
Thread 0 working...
Thread 1 working...
Thread 0 working...
Thread 1 working...
Thread 0 working...
Thread 1 working...
Thread 0 working...
Thread 0 working...
Thread 1 ident: 140376064837376
Thread 1 done.
1 <tornado.platform.epoll.EPollIOLoop object at 0x7fabdb69fba8>
Thread 0 ident: 140376073230080
Thread 0 done.
0 <tornado.platform.epoll.EPollIOLoop object at 0x7fabdd9419e8>