# -*- coding:utf-8 -*- # 多线程 对CPU密集型不利，IO密集型有利 import threading import time def start(): i = 0 for j in range(10000000): i += j return def main(): ts = {} s = time.time() for i in range(10): #start() t = threading.Thread(target=start) t.start() ts[i] = t for i in range(10): ts[i].join() # 阻塞线程，使所有线程执行完毕，再继续主线程 print(time.time()-s) # 8.16722822189331 单线程运行10次start() # 7.964332342147827 多线程运行，CPU密集型，GIL锁限制只能一个一个线程执行 number = 0 lock = threading.Lock() def add_num(): global number for i in range(1000000): lock.acquire() number += 1 lock.release() def dec_num(): global number for i in range(1000000): lock.acquire() number -= 1 lock.release() def run_threading(): global number t1 = threading.Thread(target=add_num) t2 = threading.Thread(target=dec_num) print("--start--") t1.start() t2.start() t1.join() t2.join() print(number) print("--stop--") if __name__ == '__main__': #main() run_threading()