堆棧內存溢出
  簡體   English   中英

如何在 Python 中的兩個獨立進程之間來回交換數據

[英]How to exchange data back and forth between two separate processes in Python

 原文  2020-02-23 11:23:18  9   3    python/ multiprocessing/ queue/ ipc

問題描述

問題

有兩個獨立的進程並行運行，我希望它們來回通信。

代碼說明

代碼在 Python2.7 中。 在我的精簡腳本中，我使用隊列進行進程間通信。 進程 p1 將數據放入隊列中。 進程 p2 從隊列中獲取數據並對數據進行處理。 然后進程 p2 將修改后的數據放回隊列中，最后進程 p1 從隊列中取回修改后的數據。 修改后的數據必須返回到進程 p1，因為這個進程實際上是一個發送/接收請求的 eventlet 服務器。

代碼

#!/usr/bin/python2.7 python2.7
# -*- coding: utf-8 -*-
# script for back-and-forth data exchange between processes

# common modules
import os
import sys
import time
from multiprocessing import Process
from multiprocessing import Queue
from datetime import datetime

someData = {}

class Load():
    def post(self):
        timestamp = str(datetime.now())
        someData = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        queue1.put(someData)        # put into queue
        print "#20 process 1: put in queue1 =>", someData
        time.sleep(3)

        while True:     # queue1 checking loop, comment out the loop if use time.sleep only
            if queue1.empty() == False:
                timestamp = str(datetime.now())
                res = queue1.get()
                res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
                print "#28 get from queue1 =>", res
                break
            else:
                print "#31 queue1 empty"
                time.sleep(1)

        # while True:       # queue2 checking loop
        #   if queue2.empty() == False:
        #       timestamp = str(datetime.now())
        #       res = queue2.get()
        #       res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        #       print "#39 get from queue2 =>", res
        #       break
        #   else:
        #       print "#42 queue2 empty"
        #       time.sleep(1)

class Unload():
    def get(self):
        try:
            if queue1.empty() == False:
                data = queue1.get()     # retrieve package from queue
                #queue1.close()
                #queue1.join_thread()
                timestamp = str(datetime.now())
                data = {"process":"p2","class":"Unload()","method":"get()","timestamp":timestamp} 
                print "#54 process 2: get from queue1 =>", data
                self.doSomething(data)  # call method
            else:
                print "#57 queue1 empty"
                pass
        except:
            print "#60 queue1 error"
            pass

    def doSomething(self, data):
        time.sleep(3)
        timestamp = str(datetime.now())
        someData = {"process":"p2","class":"Unload()","method":"doSomething()","timestamp":timestamp}
        self.someData = someData
        print "#68 process 2: do something =>", someData
        self.put()

    def put(self):
        time.sleep(3)
        timestamp = str(datetime.now())
        self.someData = {"process":"p2","class":"Unload()","method":"put()","timestamp":timestamp}
        print "#75 process 2: put back in queue1 =>", self.someData
        res = self.someData
        queue1.put(res)
        #print "#78 process 2: put back in queue2 =>", self.someData
        #res = self.someData
        #queue2.put(res)
        #queue2.close()
        #queue2.join_thread()

# main 
if __name__ == '__main__':

    queue1 = Queue()
    #queue2 = Queue()

    global p1, p2
    p1 = Process(target=Load().post(), args=(queue1,))      # process p1
    #p1 = Process(target=Load().post(), args=(queue1,queue2,))
    p1.daemon = True
    p1.start() 

    p2 = Process(target=Unload().get(), args=(queue1,))     # process p2
    #p2 = Process(target=Unload().get(), args=(queue1,queue2,))
    p2.start()
    p2.join()

問題我已經檢查了其他資源，但它們都涉及單向通信。 下面是資源列表。

  1. use-get-nowait-in-python-without-raise-empty-exception
  2. in-python-how-do-you-get-data-back-from-a-particular-process-using-multiprocess
  3. 如何使用多處理隊列帶鎖
  4. 多處理模塊支持鎖
  5. 我可以暫停和恢復的線程
  6. 兩個python進程之間交換數據

如何讓 process1 等待並從 process2 檢索修改后的數據？ 我是否應該考慮另一種進程之間通信的方法，例如管道、zeroMQ？

嘗試 1：在進程 1 中使用time.sleep() 沒有 while 循環只有 time.sleep 數據返回到隊列中，但從未到達進程 1 中的最終目的地。到目前為止一切順利，但最后一步是丟失的。 結果如下。

#20 process 1: put in queue1 => {'process': 'p1', 'timestamp': '2020-02-23 11:40:30.234466', 'class': 'Load()', 'method': 'post()'}
#54 process 2: get from queue1 => {'process': 'p2', 'timestamp': '2020-02-23 11:40:33.239113', 'class': 'Unload()', 'method': 'get()'}
#68 process 2: do something => {'process': 'p2', 'timestamp': '2020-02-23 11:40:36.242500', 'class': 'Unload()', 'method': 'doSomething()'}
#75 process 2: put back in queue1 => {'process': 'p2', 'timestamp': '2020-02-23 11:40:39.245856', 'class': 'Unload()', 'method': 'put()'}

嘗試 2：在進程 1 中使用 while 循環 通過 while 循環檢查隊列，數據進入隊列但隨后被捕獲，它們永遠不會到達進程 2。結果如下。

#20 process 1: put in queue1 => {'process': 'p1', 'timestamp': '2020-02-23 11:46:14.606356', 'class': 'Load()', 'method': 'post()'}
#28 get from queue1 => {'process': 'p1', 'timestamp': '2020-02-23 11:46:17.610202', 'class': 'Load()', 'method': 'post()'}
#57 queue1 empty

嘗試 3：使用兩個隊列使用兩個隊列：從進程 1 到進程 2 的隊列 1，從進程 2 到進程 1 的隊列 2。 數據進入隊列 1 但不返回隊列 2，它們神秘地消失了。 結果如下。

#20 process 1: put in queue1 => {'process': 'p1', 'timestamp': '2020-02-23 11:53:39.745177', 'class': 'Load()', 'method': 'post()'}
#42 queue2 empty

----- 更新 20200224：嘗試 4、5 和 6 --------------------- -----------------------------

嘗試 4：將兩個隊列與 manager.Queue() 一起使用

在 manager.Queue() 中使用兩個隊列：從進程 1 到進程 2 的隊列 1，從進程 2 到進程 1 的隊列 2。 數據進入 queue1 但不會返回 queue2，它們再次神秘地消失了。 代碼和結果如下。

嘗試4的代碼：#!/usr/bin/python2.7 python2.7# --coding:utf-8 --#序列化進程間數據交換的腳本

# common modules
import os
import sys
import time
import multiprocessing
from multiprocessing import Process
from multiprocessing import Queue
from multiprocessing import Manager
from datetime import datetime

someData = {}
manager = multiprocessing.Manager()
queue1 = manager.Queue()
queue2 = manager.Queue()

class Load():
    def post(self):
        timestamp = str(datetime.now())
        someData = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        queue1.put(someData)        # put into queue
        print "#20 process 1: put in queue1 =>", someData
        time.sleep(3)

        # while True:       # queue1 checking loop
        #   if queue1.empty() == False:
        #       timestamp = str(datetime.now())
        #       res = queue1.get()
        #       res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        #       print "#28 get from queue1 =>", res
        #       break
        #   else:
        #       print "#31 queue1 empty"
        #       time.sleep(1)

        while True:     # queue2 checking loop
            if queue2.empty() == False:
                timestamp = str(datetime.now())
                res = queue2.get()
                res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
                print "#39 get from queue2 =>", res
                break
            else:
                print "#42 queue2 empty"
                time.sleep(1)

class Unload():
    def get(self):
        try:
            if queue1.empty() == False:
                data = queue1.get()     # retrieve package from queue
                #queue1.close()
                #queue1.join_thread()
                timestamp = str(datetime.now())
                data = {"process":"p2","class":"Unload()","method":"get()","timestamp":timestamp} 
                print "#54 process 2: get from queue1 =>", data
                self.doSomething(data)  # call method
            else:
                print "#57 queue1 empty"
                pass
        except:
            print "#60 queue1 error"
            pass

    def doSomething(self, data):
        time.sleep(3)
        timestamp = str(datetime.now())
        someData = {"process":"p2","class":"Unload()","method":"doSomething()","timestamp":timestamp}
        self.someData = someData
        print "#68 process 2: do something =>", someData
        self.put()

    def put(self):
        time.sleep(3)
        timestamp = str(datetime.now())
        self.someData = {"process":"p2","class":"Unload()","method":"put()","timestamp":timestamp}
        res = self.someData
        #print "#75 process 2: put back in queue1 =>", self.someData
        #queue1.put(res)
        print "#78 process 2: put back in queue2 =>", self.someData
        queue2.put(res)
        #queue2.close()
        #queue2.join_thread()

# main 
if __name__ == '__main__':

    manager = multiprocessing.Manager()
    queue1 = manager.Queue()
    queue2 = manager.Queue()

    global p1, p2
    #p1 = Process(target=Load().post(), args=(queue1,))     # process p1
    p1 = Process(target=Load().post(), args=(queue1,queue2,))
    p1.daemon = True
    p1.start() 

    #p2 = Process(target=Unload().get(), args=(queue1,))        # process p2
    p2 = Process(target=Unload().get(), args=(queue1,queue2,))
    p2.start()
    p2.join()

嘗試結果4：

#20 process 1: put in queue1 => {'process': 'p1', 'timestamp': '2020-02-24 13:06:17.687762', 'class': 'Load()', 'method': 'post()'}
#42 queue2 empty

嘗試 5：將一個隊列與 manager.Queue() 一起使用將一個隊列與 manager.Queue() 一起使用：queue1 從 process1 到 process2，queue1 從 process2 返回到 process1。 數據進入 queue1，但隨后被捕獲，它們永遠不會到達進程 2。代碼結果如下。

嘗試5的代碼：

#!/usr/bin/python2.7 python2.7
# -*- coding: utf-8 -*-
# script for serialized interprocess data exchange

# common modules
import os
import sys
import time
import multiprocessing
from multiprocessing import Process
from multiprocessing import Queue
from multiprocessing import Manager
from datetime import datetime

someData = {}
manager = multiprocessing.Manager()
queue1 = manager.Queue()
#queue2 = manager.Queue()

class Load():
    def post(self):
        timestamp = str(datetime.now())
        someData = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        queue1.put(someData)        # put into queue
        print "#25 process 1: put in queue1 =>", someData
        time.sleep(3)

        while True:     # queue1 checking loop
            if queue1.empty() == False:
                timestamp = str(datetime.now())
                res = queue1.get()
                res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
                print "#33 get from queue1 =>", res
                break
            else:
                print "#36 queue1 empty"
                time.sleep(1)

        # while True:       # queue2 checking loop
        #   if queue2.empty() == False:
        #       timestamp = str(datetime.now())
        #       res = queue2.get()
        #       res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        #       print "#44 get from queue2 =>", res
        #       break
        #   else:
        #       print "#47 queue2 empty"
        #       time.sleep(1)

class Unload():
    def get(self):
        try:
            if queue1.empty() == False:
                data = queue1.get()     # retrieve package from queue
                #queue1.close()
                #queue1.join_thread()
                timestamp = str(datetime.now())
                data = {"process":"p2","class":"Unload()","method":"get()","timestamp":timestamp} 
                print "#59 process 2: get from queue1 =>", data
                self.doSomething(data)  # call method
            else:
                print "#62 queue1 empty"
                pass
        except:
            print "#65 queue1 error"
            pass

    def doSomething(self, data):
        time.sleep(3)
        timestamp = str(datetime.now())
        someData = {"process":"p2","class":"Unload()","method":"doSomething()","timestamp":timestamp}
        self.someData = someData
        print "#73 process 2: do something =>", someData
        self.put()

    def put(self):
        time.sleep(3)
        timestamp = str(datetime.now())
        self.someData = {"process":"p2","class":"Unload()","method":"put()","timestamp":timestamp}
        res = self.someData
        print "#81 process 2: put back in queue1 =>", self.someData
        queue1.put(res)
        #print "#83 process 2: put back in queue2 =>", self.someData
        #queue2.put(res)
        #queue2.close()
        #queue2.join_thread()

# main 
if __name__ == '__main__':

    manager = multiprocessing.Manager()
    queue1 = manager.Queue()
    #queue2 = manager.Queue()

    global p1, p2
    p1 = Process(target=Load().post(), args=(queue1,))      # process p1
    #p1 = Process(target=Load().post(), args=(queue1,queue2,))
    p1.daemon = True
    p1.start() 

    p2 = Process(target=Unload().get(), args=(queue1,))     # process p2
    #p2 = Process(target=Unload().get(), args=(queue1,queue2,))
    p2.start()
    p2.join()

嘗試的結果5：

#25 process 1: put in queue1 => {'process': 'p1', 'timestamp': '2020-02-24 14:08:13.975886', 'class': 'Load()', 'method': 'post()'}
#33 get from queue1 => {'process': 'p1', 'timestamp': '2020-02-24 14:08:16.980382', 'class': 'Load()', 'method': 'post()'}
#62 queue1 empty

嘗試 6：使用隊列超時

按照建議，我嘗試更正隊列超時。 方法又是 queue1 從 process1 到 process2， queue2 從 process2 到 process1。 數據進入 queue1 但不會返回 queue2，它們再次神秘地消失了。 代碼和結果如下。

嘗試6的代碼：

#!/usr/bin/python2.7 python2.7
# -*- coding: utf-8 -*-
# script for serialized interprocess data exchange

# common modules
import os
import sys
import time
import uuid
import Queue
#from Queue import Empty
import multiprocessing
from multiprocessing import Process
#from multiprocessing import Queue
from datetime import datetime

someData = {}

class Load():
    def post(self):
        timestamp = str(datetime.now())
        someData = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        queue1.put(someData)        # put into queue
        print "#24 process 1: put in queue1 =>", someData
        time.sleep(3)

        # while True:       # queue1 checking loop
        #   if queue1.empty() == False:
        #       timestamp = str(datetime.now())
        #       res = queue1.get()
        #       res = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
        #       print "#33 get from queue1 =>", res
        #       break
        #   else:
        #       print "#36 queue1 empty"
        #       time.sleep(1)

        while True:     # queue2 checking loop
            try:
                someData = queue2.get(True,1)
                timestamp = str(datetime.now())
                someData = {"process":"p1","class":"Load()","method":"post()","timestamp":timestamp}
                print "#43 process 1: got from queue2 =>", someData
                break
            except Queue.Empty:
                print "#46 process1: queue2 empty"
                continue

class Unload():
    def get(self):
        while True:     # queue2 checking loop
            try:
                someData = queue1.get(True,1)
                timestamp = str(datetime.now())
                someData = {"process":"p2","class":"Unload()","method":"get()","timestamp":timestamp} 
                print "#56 process2: got from queue1 =>", someData
                break
            except Queue.Empty:
                print "#59 process2: queue1 empty"
                continue
        self.doSomething(someData)  # call method

    def doSomething(self, data):
        time.sleep(3)
        timestamp = str(datetime.now())
        someData = {"process":"p2","class":"Unload()","method":"doSomething()","timestamp":timestamp}
        self.someData = someData
        print "#68 process2: do something =>", someData
        self.put(someData)

    def put(self,data):
        time.sleep(3)
        timestamp = str(datetime.now())
        self.someData = {"process":"p2","class":"Unload()","method":"put()","timestamp":timestamp}
        someData = self.someData
        #print "#81 process 2: put back in queue1 =>", self.someData
        #queue1.put(res)
        print "#78 process2: put back in queue2 =>", someData
        queue2.put(someData)


# main 
if __name__ == '__main__':

    queue1 = multiprocessing.Queue()
    queue2 = multiprocessing.Queue()

    global p1, p2
    #p1 = Process(target=Load().post(), args=(queue1,))     # process p1
    p1 = Process(target=Load().post(), args=(queue1,queue2,))
    p1.daemon = True
    p1.start() 

    #p2 = Process(target=Unload().get(), args=(queue1,))        # process p2
    p2 = Process(target=Unload().get(), args=(queue1,queue2,))
    p2.start()
    p2.join()

嘗試結果6：

#24 process 1: put in queue1 => {'process': 'p1', 'timestamp': '2020-02-24 18:14:46.435661', 'class': 'Load()', 'method': 'post()'}
#46 process1: queue2 empty

注意：當我在沒有類的情況下使用它時，建議的方法有效。 代碼如下：

import uuid
import multiprocessing
from multiprocessing import Process
import Queue


def load(que_in, que_out):
    request = {"id": uuid.uuid4(), "workload": "do_stuff", }
    que_in.put(request)
    print("load: sent request {}: {}".format(request["id"], request["workload"]))
    while True:
        try:
            result = que_out.get(True, 1)
        except Queue.Empty:
            continue
        print("load: got result {}: {}".format(result["id"], result["result"]))


def unload(que_in, que_out):
    def processed(request):
        return {"id": request["id"], "result": request["workload"] + " processed", }
    while True:
        try:
            request = que_in.get(True, 1)
        except Queue.Empty:
            continue
        print("unload: got request {}: {}".format(request["id"], request["workload"]))
        result = processed(request)
        que_out.put(result)
        print("unload: sent result {}: {}".format(result["id"], result["result"]))


    # main
if __name__ == '__main__':

    que_in = multiprocessing.Queue()
    que_out = multiprocessing.Queue()

    p1 = Process(target=load, args=(que_in, que_out))      # process p1
    p1.daemon = True
    p1.start()

    p2 = Process(target=unload, args=(que_in, que_out))     # process p2
    p2.start()
    p2.join()

----- 更新 20200225：嘗試 7 ---------------------------------------- -------------------------------

嘗試 7：使用一個隊列在不同的類中具有隊列超時（工作）

在這次嘗試中，我在不同類的方法之間使用了一個共享隊列，並修正了超時。 數據在共享隊列中從進程 1 到進程 2 並從進程 2 返回到進程 1。 在這次嘗試中，數據正確傳輸。 代碼和結果如下。

嘗試7的代碼：

import uuid
import multiprocessing
from multiprocessing import Process
import Queue

class Input():
    def load(self, shared_queue):
        request = {"id": uuid.uuid4(), "workload": "do_stuff", }
        shared_queue.put(request)
        print("load: sent request {}: {}".format(request["id"], request["workload"]))
        while True:
            try:
                result = shared_queue.get(True, 1)
            except Queue.Empty:
                continue
            print("load: got result {}: {}".format(result["id"], result["result"]))
            break

class Output():
    def unload(self, shared_queue):
        def processed(request):
            return {"id": request["id"], "result": request["workload"] + " processed", }
        while True:
            try:
                request = shared_queue.get(True, 1)
            except Queue.Empty:
                continue
            print("unload: got request {}: {}".format(request["id"], request["workload"]))
            result = processed(request)
            shared_queue.put(result)
            print("unload: sent result {}: {}".format(result["id"], result["result"]))


    # main
if __name__ == '__main__':

    shared_queue = multiprocessing.Queue()
    up = Input()
    down = Output()

    p1 = Process(target=up.load, args=(shared_queue,))      # process p1
    p1.daemon = True
    p1.start()


    p2 = Process(target=down.unload, args=(shared_queue,))     # process p2
    p2.start()

    p1.join()
    p2.join()

嘗試結果7：

load: sent request a461357a-b39a-43c4-89a8-a77486a5bf45: do_stuff
unload: got request a461357a-b39a-43c4-89a8-a77486a5bf45: do_stuff
unload: sent result a461357a-b39a-43c4-89a8-a77486a5bf45: do_stuff processed
load: got result a461357a-b39a-43c4-89a8-a77486a5bf45: do_stuff processed

3 個解決方案

解決方案1
 1  2020-02-23 12:34:27

我想你只是錯過了隊列超時的使用

try:
    result = que_out.get(True, 1)
except queue.Empty:
    continue

這個簡化的例子可以幫助你：

import uuid
from multiprocessing import Process
from multiprocessing import Queue
import queue


def load(que_in, que_out):
    request = {"id": uuid.uuid4(), "workload": "do_stuff", }
    que_in.put(request)
    print("load: sent request {}: {}".format(request["id"], request["workload"]))
    while True:
        try:
            result = que_out.get(True, 1)
        except queue.Empty:
            continue
        print("load: got result {}: {}".format(result["id"], result["result"]))


def unload(que_in, que_out):

    def processed(request):
        return {"id": request["id"], "result": request["workload"] + " processed", }

    while True:
        try:
            request = que_in.get(True, 1)
        except queue.Empty:
            continue
        print("unload: got request {}: {}".format(request["id"], request["workload"]))
        result = processed(request)
        que_out.put(result)
        print("unload: sent result {}: {}".format(result["id"], result["result"]))

    # main
if __name__ == '__main__':

    que_in = Queue()
    que_out = Queue()

    p1 = Process(target=load, args=(que_in, que_out))      # process p1
    p1.daemon = True
    p1.start()

    p2 = Process(target=unload, args=(que_in, que_out))     # process p2
    p2.start()
    p2.join()

輸出

load: sent request d9894e41-3e8a-4474-9563-1a99797bc722: do_stuff
unload: got request d9894e41-3e8a-4474-9563-1a99797bc722: do_stuff
unload: sent result d9894e41-3e8a-4474-9563-1a99797bc722: do_stuff processed
load: got result d9894e41-3e8a-4474-9563-1a99797bc722: do_stuff processed

解決方案2
 0  2020-02-23 12:01:05

您必須使用 Manager-wrapped queue(s) 來跨進程傳播更改，否則每個進程都有其單獨的隊列對象並且無法看到其他進程。 管理器為所有子進程創建隊列的共享實例。

所以queue1 = Queue()變成了queue1 = manager.Queue() ， from multiprocessing import Manager在頂部。 如果你想使用你的兩個隊列方法，你顯然必須以相同的方式包裝第二個隊列。

相關資源：

來自一個多處理管理器的多個隊列

Python 文檔

解決方案3
 0 已采納  2020-02-26 09:48:06

解決方案：使用一個共享隊列

在遵循建議並進行一些調整以正確定位不同的類方法后，我解決了這個問題。 兩個獨立進程之間的數據來回流動現在是正確的。 對我來說，一個重要的注意事項是要格外注意在兩個獨立進程之間交換的someData包，它確實必須是被someData的同一個包。 因此，標識符條目"id": uuid.uuid4()用於檢查每個段落的包是否相同。

#!/usr/bin/python2.7 python2.7
# -*- coding: utf-8 -*-
# script for back and forth communication between two separate processes using a shared queue

# common modules
import os
import sys
import time
import uuid
import Queue
import multiprocessing
from multiprocessing import Process
from datetime import datetime


someData = {}


class Load():
    def post(self, sharedQueue):
        timestamp = str(datetime.now()) # for timing checking
        someData = {"timestamp":timestamp, "id": uuid.uuid4(), "workload": "do_stuff",}
        self.someData = someData
        sharedQueue.put(someData)       # put into the shared queue
        print("#25 p1 load: sent someData {}: {}".format(someData["id"], someData["timestamp"], someData["workload"]))
        time.sleep(1)   # for the time flow     

        while True:     # sharedQueue checking loop
            try:
                time.sleep(1)   # for the time flow
                timestamp = str(datetime.now())
                someData = sharedQueue.get(True,1)
                someData["timestamp"] = timestamp
                print("#37 p1 load: got back someData {}: {}".format(someData["id"], someData["timestamp"], someData["workload"]))
                break
            except Queue.Empty:
                print("#37 p1: sharedQueue empty")
                continue
            break


class Unload():
    def get(self, sharedQueue):
        while True:     # sharedQueue checking loop
            try:
                someData = sharedQueue.get(True,1)
                self.someData = someData
                timestamp = str(datetime.now())
                someData["timestamp"] = timestamp
                print("#50 p2 unload: got someData {}: {}".format(someData["id"], someData["timestamp"], someData["workload"]))
                break
            except Queue.Empty:
                print("#53 p2: sharedQueue empty")
                continue
        time.sleep(1)               # for the time flow
        self.doSomething(someData)  # pass the data to the method


    def doSomething(self, someData):    # execute some code here
        timestamp = str(datetime.now())
        someData["timestamp"] = timestamp
        print("#62 p2 unload: doSomething {}: {}".format(someData["id"], someData["timestamp"], someData["workload"]))
        self.put(someData)
        time.sleep(1)   # for the time flow


    def put(self,someData):
        timestamp = str(datetime.now())
        someData["timestamp"] = timestamp
        sharedQueue.put(someData)
        print("#71 p2 unload: put someData {}: {}".format(someData["id"], someData["timestamp"], someData["workload"]))
        time.sleep(1)   # for the time flow


# main 
if __name__ == '__main__':

    sharedQueue = multiprocessing.Queue()

    trx = Load()
    rcx = Unload()

    p1 = Process(target=trx.post, args=(sharedQueue,))      # process p1
    p1.daemon = True
    p1.start() 

    p2 = Process(target=rcx.get, args=(sharedQueue,))       # process p2
    p2.start()

    p1.join()
    p2.join()

暫無
暫無

聲明:本站的技術帖子網頁，遵循CC BY-SA 4.0協議，如果您需要轉載，請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

相關問題 如何在不同conda環境的兩個不同python進程之間交換數據？ 在兩個過程之間交換價值？ 如何在java和python之間來回發送數據數組？ 如何溝通兩個單獨的python進程？ 在兩個類之間來回傳遞參數 如何讓jQuery和Python在GAE應用程序中來回發送數據 Python-在函數之間來回傳遞參數 在 python 中的集合和元組之間來回 python多處理在不同的python進程之間共享數據 如何在腳本之間來回傳遞信息
相關標簽
 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM