Add run_now() method to tornado.ioloop.PeriodicCallback

periodiccallback.py

import tornado.ioloop

class PeriodicCallback(tornado.ioloop.PeriodicCallback):
    def run_now(self):
        self.stop()
        self._running = True
        try:
            return self.callback()
        except Exception:
            self.io_loop.handle_callback_exception(self.callback)
        finally:
            self.start()

test.py

import tornado.ioloop
from periodiccallback import PeriodicCallback
import time

def cb():
    print("CB called at ", time.ctime())

def cb2():
    print("call PeriodicCallback immediately")
    pc.run_now()

pc = PeriodicCallback(cb, 3000)
pc.start()      # run CB every 3 sec

PeriodicCallback(cb2, 10000).start()    # run it immediately every 10 sec

tornado.ioloop.IOLoop.instance().start()