Killing all threads and the process from a thread

问题:

I have a process which spawns 2 types of thread classes. One thread is responsible for consuming a job_queue (100Threads of this class are usually running). And second thread is a killing thread. I am using a result_done flag which is being set from thread2 and the issue is my threads1 wait for X seconds and then check if result_done flag is set.

def run(self):
    while True:
        try:
            val = self.job_queue.get(True,self.maxtimeout) 
        except:
            pass
        if self.result_done.isset():
            return

Now, if maxtimeout is set to 500seconds and I set the result_done flag from another thread, this thread will wait for 500 seconds before exiting( if there's no data in the queue).

What I want to achieve is that all the threads die gracefully along with the current process, properly terminating the db,websocket,http connections etc as soon as result_done event is set from any of the threads of the process.

I am using python multiprocess library to create the process which spawns these threads.

Update: All threads are daemon=True threads.

回答1:

To avoid waiting maxtimeout time, you could use Event.wait() method:

def run(self):
    while not self.result_done.is_set():
        try:
            val = self.job_queue.get_nowait()
        except Empty:
            if self.result_done.wait(1): # wait a second to avoid busy loop
                return 

Event.wait(timeout) returns without waiting the full timeout if the event is set during the call.