# -*- coding: utf-8 -*- import time from multiprocessing import Process from threading import Thread def func(): ret = 0 for i in range(10000000): ret += i if __name__ == '__main__': '''计算密集型''' start_time = time.time() p_lst = [] for i in range(10): # p = Process(target=func) p = Thread(target=func) p_lst.append(p) p.start() [pp.join() for pp in p_lst] end_time = time.time() print("run time is :%s" % (end_time-start_time)) # run time is :3.555203437805176 # 多进程的运行时间,4个cpu同时处理 # run time is :9.960569858551025 # 多线程的运行时间,一个cpu去处理 # 多核计算密集型的,选择多进程,可以充分利用cpu
# -*- coding: utf-8 -*- import time from multiprocessing import Process from threading import Thread def func(): time.sleep(1) if __name__ == '__main__': '''IO密集型''' start_time = time.time() p_lst = [] for i in range(10): # p = Process(target=func) p = Thread(target=func) p_lst.append(p) p.start() [pp.join() for pp in p_lst] end_time = time.time() print("run time is :%s" % (end_time-start_time)) # run time is :1.660094976425171 # 多进程的运行时间,4个cpu同时处理,因为进程比线程的开销大 # run time is :1.0020575523376465 # 多线程的运行时间,一个cpu去处理 # 多核IO密集型的,选择多线程,线程开销小
守护线程和守护进程的区别
守护进程:随着主进程的代码执行结束,而结束
守护线程:随着所有非守护线程的执行结束而结束
