求解协程+多进程的正确使用姿势

用 asyncio 做了一个 UDP 传输性能测试工具，目前单进程服务端性能不够，流量大的时候处理不过来，服务端用的 asyncio.DatagramProtocol，怎么变成多进程的呢？试试了一下抢占式的写法，运行报错了，运行起来也只有一个进程工作，上代码

import asyncio import time import socket from multiprocessing import Process loop = asyncio.get_event_loop() size = 0 class ServerProtocol(asyncio.DatagramProtocol): def connection_made(self, transport): self.transport = transport def datagram_received(self, data, addr, args=None): global size data = data.decode() message = data index = data.find('\n') if index > 0: filename = data[0:index] data = data[index+1::] size += len(data) task = self.WriteToFile(filename, data) asyncio.run_coroutine_threadsafe(task, loop) async def WriteToFile(self, f, data): await asyncio.sleep(1) return True async def print_size(): global size while True: await asyncio.sleep(1) print(size) def start(sock): listen = loop.create_datagram_endpoint( ServerProtocol, sock = sock ) transport, protocol = loop.run_until_complete(listen) task = print_size() asyncio.run_coroutine_threadsafe(task, loop) try: loop.run_forever() except KeyboardInterrupt: pass transport.close() loop.close() sock.close() if __name__ == '__main__': print("Starting UDP server") sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) sock.bind(('0.0.0.0', 9873)) for i in range(1): t = Process(target=start, args=(sock,)) t.deamon = True t.start() start(sock) 

报错信息

Exception in callback BaseSelectorEventLoop._add_reader(6, <bound method..., bufsize=0>>>) handle: <Handle BaseSelectorEventLoop._add_reader(6, <bound method..., bufsize=0>>>)> Traceback (most recent call last): File "/usr/local/python36/lib/python3.6/asyncio/selector_events.py", line 264, in _add_reader key = self._selector.get_key(fd) File "/usr/local/python36/lib/python3.6/selectors.py", line 191, in get_key raise KeyError("{!r} is not registered".format(fileobj)) from None KeyError: '6 is not registered' During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/usr/local/python36/lib/python3.6/asyncio/events.py", line 145, in _run self._callback(*self._args) File "/usr/local/python36/lib/python3.6/asyncio/selector_events.py", line 267, in _add_reader (handle, None)) File "/usr/local/python36/lib/python3.6/selectors.py", line 412, in register self._epoll.register(key.fd, epoll_events) FileExistsError: [Errno 17] File exists