一、通过类创建子线程
1 import threading
2 class MyThread(threading.Thread):
3 def __init__(self,num):
4 threading.Thread.__init__(self)
5 self.num = num
6 def run(self):
7 print('running on number %s' %self.num)
8 if __name__ == '__main__':
9 t1 = MyThread(1)
10 t2 = MyThread(2)
11 t1.start()
12 t2.start()
二、同步锁
import time
import threading
def cal():
global num
r.acquire() #上锁
temp = num
time.sleep(0.001)
num = temp-1
r.release() #开锁
1.被上锁的代码不执行完，GIL锁不释放，线程不切换
2.开锁后，多线程正常运行
1 num = 100
2 thread_list = []
3 r = threading.Lock() #创建锁
4 for i in range(100):
5 t = threading.Thread(target=cal)
6 t.start()
7 thread_list.append(t)
8
9 for t in thread_list: #等待所有子线程执行完毕
10 t.join()
11
12 print(num)