Python Socket 多进程工作池

Question

我需要通过套接字接收连接，读取输入数据，进行复杂且耗时的计算，然后发送答案。同时可能会有很多请求（比如100个）。

我了解到，由于全局解释器锁（GIL）的原因，我不能使用普通的线程，所以我尝试用C++和boost库来创建线程，并在每个线程中运行Python的子解释器。但无论如何，这样做都无法让所有的核心同时100%利用。

因此，我决定使用多进程的方法，创建一个固定数量的工作进程来处理这些请求，并使用队列来管理。这样，我们就不需要浪费时间去创建新进程，也不会同时有100个或更多的进程，只会有固定数量的进程。

我对Python还很陌生，之前主要使用C++。

现在我有了这段代码，但它并没有正常工作。连接打开后就立即关闭，我不知道为什么：

#!/usr/bin/env python   
import os
import sys
import SocketServer
import Queue
import time
import socket
import multiprocessing
from multiprocessing.reduction import reduce_handle
from multiprocessing.reduction import rebuild_handle 

class MultiprocessWorker(multiprocessing.Process):

    def __init__(self, sq):

        self.SLEEP_INTERVAL = 1

        # base class initialization
        multiprocessing.Process.__init__(self)

        # job management stuff
        self.socket_queue = sq
        self.kill_received = False

    def run(self):
        while not self.kill_received:
            try:     
                h = self.socket_queue.get_nowait()          
                fd=rebuild_handle(h)
                client_socket=socket.fromfd(fd,socket.AF_INET,socket.SOCK_STREAM)
                #client_socket.send("hellofromtheworkerprocess\r\n")
                received = client_socket.recv(1024)
                print "Recieved on client: ",received
                client_socket.close()

            except Queue.Empty:
                pass

            #Dummy timer
            time.sleep(self.SLEEP_INTERVAL)

class MyTCPHandler(SocketServer.BaseRequestHandler):
    """
    The RequestHandler class for our server.

    It is instantiated once per connection to the server, and must
    override the handle() method to implement communication to the
    client.
    """

    def handle(self):
        # self.request is the TCP socket connected to the client
        #self.data = self.request.recv(1024).strip()
        #print "{} wrote:".format(self.client_address[0])
        #print self.data
        # just send back the same data, but upper-cased
        #self.request.sendall(self.data.upper())

        #Either pipe it to worker directly like this
        #pipe_to_worker.send(h) #instanceofmultiprocessing.Pipe
        #or use a Queue :)

        h = reduce_handle(self.request.fileno())
        socket_queue.put(h)


if __name__ == "__main__":

    #Mainprocess
    address =  ('localhost', 8082)
    server = SocketServer.TCPServer(address, MyTCPHandler)
    socket_queue = multiprocessing.Queue()

    for i in range(5):
        worker = MultiprocessWorker(socket_queue)
        worker.start()

    try:
        server.serve_forever()
    except KeyboardInterrupt:
        sys.exit(0)

request handling socket multiprocessing queue management global interpreter lock work pool c++ threading input data processing

Python Socket 多进程工作池

2 个回答

撰写回答