python实现多进程代码示例

# -*- coding:utf-8 -*-
from multiprocessing import Process, Pool
import os
import time


def run_proc(wTime):
  n = 0
  while n < 3:
    print "subProcess %s run," % os.getpid(), "{0}".format(time.ctime())  #获取当前进程号和正在运行是的时间
    time.sleep(wTime)  #等待（休眠）
    n += 1

if __name__ == "__main__":
  p = Process(target=run_proc, args=(2,)) #申请子进程
  p.start()   #运行进程
  print "Parent process run. subProcess is ", p.pid
  print "Parent process end,{0}".format(time.ctime())

# -*- coding:utf-8 -*-
from multiprocessing import Process, Pool
import os
import time


def run_proc(wTime):
  n = 0
  while n < 3:
    print "subProcess %s run," % os.getpid(), "{0}".format(time.ctime())
    time.sleep(wTime)
    n += 1

if __name__ == "__main__":
  p = Process(target=run_proc, args=(2,))
  p.daemon = True  #加入daemon
  p.start()
  print "Parent process run. subProcess is ", p.pid
  print "Parent process end,{0}".format(time.ctime())

# -*- coding:utf-8 -*-
from multiprocessing import Process, Pool
import os
import time


def run_proc(wTime):
  n = 0
  while n < 3:
    print "subProcess %s run," % os.getpid(), "{0}".format(time.ctime())
    time.sleep(wTime)
    n += 1

if __name__ == "__main__":
  p = Process(target=run_proc, args=(2,))
  p.daemon = True
  p.start()
  p.join()  #加入join方法
  print "Parent process run. subProcess is ", p.pid
  print "Parent process end,{0}".format(time.ctime())

# -*- coding:utf-8 -*-
from multiprocessing import Process, Pool
import os
import time


class Myprocess(Process):

  def __init__(self, wTime):
    Process.__init__(self)
    self.wTime = wTime

  def run(self):
    n = 0
    while n < 3:
      print "subProcess %s run," % os.getpid(), "{0}".format(time.ctime())
      time.sleep(self.wTime)
      n += 1


if __name__ == "__main__":
  p = Myprocess(2)
  p.daemon = True
  p.start()  #自动调用run方法
  p.join()
  print "Parent process run. subProcess is ", p.pid
  print "Parent process end,{0}".format(time.ctime())

# -*- coding:utf-8 -*-
from multiprocessing import Process,Pool
import os,time

def run_proc(name):    ##定义一个函数用于进程调用
  for i in range(5):  
    time.sleep(0.2)  #休眠0.2秒
    print 'Run child process %s (%s)' % (name, os.getpid())
#执行一次该函数共需1秒的时间

if __name__ =='__main__': #执行主进程
  print 'Run the main process (%s).' % (os.getpid())
  mainStart = time.time() #记录主进程开始的时间
  p = Pool(8)      #开辟进程池
  for i in range(16):                 #开辟14个进程
    p.apply_async(run_proc,args=('Process'+str(i),))#每个进程都调用run_proc函数，
                            #args表示给该函数传递的参数。

  print 'Waiting for all subprocesses done ...'
  p.close() #关闭进程池
  p.join() #等待开辟的所有进程执行完后，主进程才继续往下执行
  print 'All subprocesses done'
  mainEnd = time.time() #记录主进程结束时间
  print 'All process ran %0.2f seconds.' % (mainEnd-mainStart) #主进程执行时间