import multiprocessing


def download_data(q):
  """下载数据"""
  # 模拟从网上下载数据
  data = [11, 22, 33, 44]

  # 向队列中写入数据
  for temp in data:
    q.put(temp)
  print("----数据下载完成并且已存入队列----")


def analysis_data(q):
  """数据处理"""
  waitting_analysis_data = list()
  # 从队列中获取数据
  while True:
    data = q.get()
    waitting_analysis_data.append(data)
    if q.empty():
      break
  print(waitting_analysis_data)


def main():
  # 1.创建一个队列
  q = multiprocessing.Queue()
  q1 = multiprocessing.Process(target=download_data, args=(q,))
  q2 = multiprocessing.Process(target=analysis_data, args=(q,))
  q1.start()
  q2.start()


if __name__ == '__main__':
  main()

from multiprocessing import Pool
import os, time, random


def worker(msg):
  t_start = time.time()
  print("进程%s开始执行，进程号为%d" % (msg, os.getpid()))
  # random.random()随机生成0-1之间的浮点数
  time.sleep(random.random()*2)
  t_stop = time.time()
  print("进程",msg,"执行完成,耗时%0.2f" % (t_stop-t_start))


def main():
  # 定义一个进程池，最大进程数为3
  po = Pool(3)
  for i in range(10):
    # Pool().apply_async(要调用的目标，(传递给目标的参数元组，))
    # 每次循环将会用空闲出来的子进程去调用目标
    po.apply_async(worker,(i,))

  print("----start----")
  # 关闭进程池，关闭后po不再接受新的请求
  po.close()
# 等待po中所有子进程执行完成，必须放在close语句之后
  po.join()

  print("----end----")


if __name__ == '__main__':
  main()