process_进程池_2

import multiprocessing
import os, time, random

def Lee():
    print("\nRun task Lee-%s" %(os.getpid()) ) #os.getpid()获取当前的进程的ID
    start = time.time()
    time.sleep(random.random() * 10) #random.random()随机生成0-1之间的小数
    end = time.time()
    print('Task Lee, runs %0.2f seconds.' %(end - start))

def Marlon():
    print("\nRun task Marlon-%s" %(os.getpid()))
    start = time.time()
    time.sleep(random.random() * 40)
    end=time.time()
    print('Task Marlon runs %0.2f seconds.' %(end - start))

def Allen():
    print("\nRun task Allen-%s" %(os.getpid()))
    start = time.time()
    time.sleep(random.random() * 30)
    end = time.time()
    print( 'Task Allen runs %0.2f seconds.' %(end - start))

def Frank():
    print("\nRun task Frank-%s" %(os.getpid()))
    start = time.time()
    time.sleep(random.random() * 20)
    end = time.time()
    print( 'Task Frank runs %0.2f seconds.' %(end - start))
if __name__=='__main__':
    function_list=  [Lee, Marlon, Allen, Frank]
    print( "parent process %s" %(os.getpid()))

    pool=multiprocessing.Pool(2)
    for func in function_list:
        pool.apply_async(func)

    print('Waiting for all subprocesses done...')
    pool.close()
    pool.join()
    print('All subprocesses done.')

'''
parent process 3240
Waiting for all subprocesses done...

Run task Lee-13652

Run task Marlon-13528
Task Lee, runs 3.34 seconds.

Run task Allen-13652
Task Allen runs 14.78 seconds.

Run task Frank-13652
Task Frank runs 2.45 seconds.
Task Marlon runs 32.62 seconds.
All subprocesses done.
'''