Python3 - 多进程

from multiprocessing import Process
   def disp():
      print ('Hello !! Welcome to Python Tutorial')
      if __name__ == '__main__':
      p = Process(target=disp)
      p.start()
      p.join()

# Python multiprocessing example
# importing the multiprocessing module

import multiprocessing
def cube(n):
   # 此功能将打印给定数量的多维数据集
   print("The Cube is: {}".format(n * n * n))

def square(n):
    # 此功能将打印给定数量的正方形
   print("The Square is: {}".format(n * n))

if __name__ == "__main__":
   # 创建两个进程
   process1 = multiprocessing.Process(target= square, args=(5, ))
   process2 = multiprocessing.Process(target= cube, args=(5, ))

   # 在这里，我们开始这个进程1
   process1.start()
   # 在这里，我们开始进程2
   process2.start()

   # join()方法用于等待进程1完成
   process1.join()
   # 它用于等待进程1完成
   process2.join()

   # 如果两个进程都完成，请打印
   print("Both processes are finished")

process1 = multiprocessing.Process(target= square, args=(5, ))
process2 = multiprocessing.Process(target= cube, args=(5, ))

process1.start()
process2.start()

import multiprocessing
print("The number of CPU currently working in system : ", multiprocessing.cpu_count())

# Importing Queue Class

from multiprocessing import Queue

fruits = ['Apple', 'Orange', 'Guava', 'Papaya', 'Banana']
count = 1
# creating a queue object
queue = Queue()
print('pushing items to the queue:')
for fr in fruits:
    print('item no: ', count, ' ', fr)
    queue.put(fr)
    count += 1

print('\npopping items from the queue:')
count = 0
while not queue.empty():
    print('item no: ', count, ' ', queue.get())
    count += 1

from multiprocessing import Lock, Process, Queue, current_process
import time
import queue 


def jobTodo(tasks_to_perform, complete_tasks):
    while True:
        try:

            # The try block to catch task from the queue.
            # The get_nowait() function is used to
            # raise queue.Empty exception if the queue is empty.

            task = tasks_to_perform.get_nowait()

        except queue.Empty:

            break
        else:

                # if no exception has been raised, the else block will execute
                # add the task completion
                

            print(task)
            complete_tasks.put(task + ' is done by ' + current_process().name)
            time.sleep(.5)
    return True


def main():
    total_task = 8
    total_number_of_processes = 3
    tasks_to_perform = Queue()
    complete_tasks = Queue()
    number_of_processes = []

    for i in range(total_task):
        tasks_to_perform.put("Task no " + str(i))

    # defining number of processes
    for w in range(total_number_of_processes):
        p = Process(target=jobTodo, args=(tasks_to_perform, complete_tasks))
        number_of_processes.append(p)
        p.start()

    # completing process
    for p in number_of_processes:
        p.join()

    # print the output
    while not complete_tasks.empty():
        print(complete_tasks.get())

    return True


if __name__ == '__main__':
    main()

from multiprocessing import Pool
import time

w = (["V", 5], ["X", 2], ["Y", 1], ["Z", 3])


def work_log(data_for_work):
    print(" Process name is %s waiting time is %s seconds" % (data_for_work[0], data_for_work[1]))
    time.sleep(int(data_for_work[1]))
    print(" Process %s Executed." % data_for_work[0])


def handler():
    p = Pool(2)
    p.map(work_log, w)

if __name__ == '__main__':
    handler()

from multiprocessing import Pool
def fun(x):
    return x*x

if __name__ == '__main__':
    with Pool(5) as p:
        print(p.map(fun, [1, 2, 3]))

from multiprocessing import Manager
manager = Manager()
l = manager.list([i*i for i in range(10)])
print(l)
print(repr(l))
print(l[4])
print(l[2:5])