[Tips] python 多进行使用

快速实现

1. 同一个函数不同的输入数据

from multiprocessing import Pool
import os, time, random

def task1(name):
    print('Run task %s (%s)...' % (name, os.getpid()))
    start = time.time()
    time.sleep(random.random() * 3)
    end = time.time()
    print('Task %s runs %0.2f seconds.' % (name, (end - start)))

if __name__=='__main__':
    print('Parent process %s.' % os.getpid())
    p = Pool(4)
    for i in range(5):
        p.apply_async(task1, args=(i,))
    print('Waiting for all subprocesses done...')
    p.close()
    p.join()
    print('All subprocesses done.')

　　

或者采用pool的map函数,但是注意这个返回的结果顺序和输入的i_list并不一致：

#coding: utf-8
import multiprocessing 

def m1(x): 
    return x * x 

if __name__ == '__main__': 
    pool = multiprocessing.Pool(multiprocessing.cpu_count()) 
    i_list = range(8)
    results = pool.map(m1, i_list)
    print(results)