# 计算密集型
from multiprocessing import Process
from threading import Thread
#mport os,time
def work():res=0for i in range(100000000):res*=iif __name__ == '__main__':l=[]print(os.cpu_count())  # 本机为6核start=time.time()for i in range(6):# p=Process(target=work) #耗时  4.732933044433594p=Thread(target=work) #耗时 22.83087730407715
        l.append(p)p.start()for p in l:p.join()stop=time.time()print('run time is %s' %(stop-start))

# IO密集型
from multiprocessing import Process
from threading import Thread
import threading
import os,time
def work():time.sleep(2)if __name__ == '__main__':l=[]print(os.cpu_count()) #本机为6核start=time.time()for i in range(4000):p=Process(target=work) #耗时9.001083612442017s多,大部分时间耗费在创建进程上# p=Thread(target=work) #耗时2.051966667175293s多
        l.append(p)p.start()for p in l:p.join()stop=time.time()print('run time is %s' %(stop-start))

from threading import Event,Thread
import time# 先生成一个event对象
e = Event()def light():print('红灯正亮着')time.sleep(3)e.set()  # 发信号print('绿灯亮了')def car(name):print('%s正在等红灯'%name)e.wait()  # 等待信号print('%s加油门飙车了'%name)t = Thread(target=light)
t.start()for i in range(10):t = Thread(target=car,args=('伞兵%s'%i,))t.start()

from threading import Semaphore,Thread
import time
import randomsm = Semaphore(5)  # 造了一个含有五个的坑位的公共厕所def task(name):sm.acquire()print('%s占了一个坑位'%name)time.sleep(random.randint(1,3))sm.release()for i in range(40):t = Thread(target=task,args=(i,))t.start()

class MyThread(Thread):def run(self):  # 创建线程自动触发run方法 run方法内调用func1 func2相当于也是自动触发
        self.func1()self.func2()def func1(self):mutexA.acquire()print('%s抢到了A锁'%self.name)  # self.name等价于current_thread().name
        mutexB.acquire()print('%s抢到了B锁'%self.name)mutexB.release()print('%s释放了B锁'%self.name)mutexA.release()print('%s释放了A锁'%self.name)def func2(self):mutexB.acquire()print('%s抢到了B锁'%self.name)time.sleep(1)mutexA.acquire()print('%s抢到了A锁' % self.name)mutexA.release()print('%s释放了A锁' % self.name)mutexB.release()print('%s释放了B锁' % self.name)for i in range(10):t = MyThread()t.start()

import threadingclass MyThread(threading.Thread):def run(self):global n1, n2lock.acquire()   # 加锁n1 += 1print(self.name + ' set n1 to ' + str(n1))lock.acquire()   # 再次加锁n2 += n1print(self.name + ' set n2 to ' + str(n2))lock.release()lock.release()n1, n2 = 0, 0
lock = threading.RLock()if __name__ == '__main__':thread_list = []for i in range(5):t = MyThread()t.start()thread_list.append(t)for t in thread_list:t.join()print('final num:%d ,%d' % (n1, n2))