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第五篇进程&线程&协程

多进程

 1 #方式一：
 2 # from multiprocessing import Process
 3 # import time
 4 #
 5 # def task(name):
 6 #     print('%s is running' %name)
 7 #     time.sleep(3)
 8 #     print('%s is done' %name)
 9 #
10 # if __name__ == '__main__':
11 #     # Process(target=task,kwargs={'name':'子进程1'})
12 #     p=Process(target=task,args=('子进程1',))
13 #     p.start() #仅仅只是给操作系统发送了一个信号
14 #
15 #     print('主')
16 
17 #方式二
18 from multiprocessing import Process
19 import time
20 
21 class MyProcess(Process):
22     def __init__(self,name):
23         super().__init__()
24         self.name=name
25 
26     def run(self):
27         print('%s is running' %self.name)
28         time.sleep(3)
29         print('%s is done' %self.name)
30 
31 
32 if __name__ == '__main__':
33     p=MyProcess('子进程1')
34     p.start()
35     print('主')

开启进程的2种方式

 1 from multiprocessing import Process
 2 import time,os
 3 
 4 def task():
 5     print('%s is running,parent id is <%s>' %(os.getpid(),os.getppid()))
 6     time.sleep(3)
 7     print('%s is done,parent id is <%s>' %(os.getpid(),os.getppid()))
 8 
 9 if __name__ == '__main__':
10     p=Process(target=task,)
11     p.start()
12 
13     print('主',os.getpid(),os.getppid())

查看pid

  1 #join方法
  2 # from multiprocessing import Process
  3 # import time,os
  4 #
  5 # def task():
  6 #     print('%s is running,parent id is <%s>' %(os.getpid(),os.getppid()))
  7 #     time.sleep(3)
  8 #     print('%s is done,parent id is <%s>' %(os.getpid(),os.getppid()))
  9 #
 10 # if __name__ == '__main__':
 11 #     p=Process(target=task,)
 12 #     p.start()
 13 #
 14 #     p.join()
 15 #     print('主',os.getpid(),os.getppid())
 16 #     print(p.pid)
 17 
 18 
 19 # from multiprocessing import Process
 20 # import time,os
 21 #
 22 # def task(name,n):
 23 #     print('%s is running' %name)
 24 #     time.sleep(n)
 25 #
 26 #
 27 # if __name__ == '__main__':
 28 #     start=time.time()
 29 #     p1=Process(target=task,args=('子进程1',5))
 30 #     p2=Process(target=task,args=('子进程2',3))
 31 #     p3=Process(target=task,args=('子进程3',2))
 32 #     p_l=[p1,p2,p3]
 33 #
 34 #     # p1.start()
 35 #     # p2.start()
 36 #     # p3.start()
 37 #     for p in p_l:
 38 #         p.start()
 39 #
 40 #     # p1.join()
 41 #     # p2.join()
 42 #     # p3.join()
 43 #     for p in p_l:
 44 #         p.join()
 45 #
 46 #     print('主',(time.time()-start))
 47 
 48 
 49 
 50 
 51 
 52 # from multiprocessing import Process
 53 # import time,os
 54 #
 55 # def task(name,n):
 56 #     print('%s is running' %name)
 57 #     time.sleep(n)
 58 #
 59 #
 60 # if __name__ == '__main__':
 61 #     start=time.time()
 62 #     p1=Process(target=task,args=('子进程1',5))
 63 #     p2=Process(target=task,args=('子进程2',3))
 64 #     p3=Process(target=task,args=('子进程3',2))
 65 #
 66 #     p1.start()
 67 #     p1.join()
 68 #     p2.start()
 69 #     p2.join()
 70 #     p3.start()
 71 #     p3.join()
 72 #
 73 #     print('主',(time.time()-start))
 74 
 75 
 76 #了解:is_alive
 77 from multiprocessing import Process
 78 import time,os
 79 
 80 def task():
 81     print('%s is running,parent id is <%s>' %(os.getpid(),os.getppid()))
 82     time.sleep(3)
 83     print('%s is done,parent id is <%s>' %(os.getpid(),os.getppid()))
 84 
 85 if __name__ == '__main__':
 86     # p=Process(target=task,)
 87     # p.start()
 88     # # print(p.is_alive())
 89     # p.join()
 90     # print('主',os.getpid(),os.getppid())
 91     # print(p.pid)
 92     # # print(p.is_alive())
 93 
 94 
 95 
 96     p=Process(target=task,name='sub——Precsss')
 97     p.start()
 98     p.terminate()
 99     time.sleep(3)
100     print(p.is_alive())
101     print('主')
102     print(p.name)

Process对象的其他属性

 1 # from multiprocessing import Process
 2 # import time
 3 #
 4 # def task(name):
 5 #     print('%s is running' %name)
 6 #     time.sleep(2)
 7 #     p=Process(target=time.sleep,args=(3,))
 8 #     p.start()
 9 #
10 #
11 # if __name__ == '__main__':
12 #     p=Process(target=task,args=('子进程1',))
13 #     p.daemon=True
14 #     p.start()
15 #
16 #     p.join()
17 #     print('主')
18 
19 
20 #练习题
21 from multiprocessing import Process
22 
23 import time
24 def foo():
25     print(123)
26     time.sleep(1)
27     print("end123")
28 
29 def bar():
30     print(456)
31     time.sleep(3)
32     print("end456")
33 
34 if __name__ == '__main__':
35     p1=Process(target=foo)
36     p2=Process(target=bar)
37 
38     p1.daemon=True
39     p1.start()
40     p2.start()
41     print("main-------")

守护进程

 1 from multiprocessing import Process,Lock
 2 import json
 3 import time
 4 
 5 def search(name):
 6     time.sleep(1)
 7     dic=json.load(open('db.txt','r',encoding='utf-8'))
 8     print('<%s> 查看到剩余票数【%s】' %(name,dic['count']))
 9 
10 
11 def get(name):
12     time.sleep(1)
13     dic=json.load(open('db.txt','r',encoding='utf-8'))
14     if dic['count'] > 0:
15         dic['count']-=1
16         time.sleep(3)
17         json.dump(dic,open('db.txt','w',encoding='utf-8'))
18         print('<%s> 购票成功' %name)
19 
20 
21 def task(name,mutex):
22     search(name)
23     mutex.acquire()
24     get(name)
25     mutex.release()
26 
27 if __name__ == '__main__':
28     mutex=Lock()
29     for i in range(10):
30         p=Process(target=task,args=('路人%s' %i,mutex))
31         p.start()

互斥锁-模拟抢票示例

 1 from multiprocessing import Process,Lock
 2 import json
 3 import time
 4 
 5 def search(name):
 6     time.sleep(1)
 7     dic=json.load(open('db.txt','r',encoding='utf-8'))
 8     print('<%s> 查看到剩余票数【%s】' %(name,dic['count']))
 9 
10 
11 def get(name):
12     time.sleep(1)
13     dic=json.load(open('db.txt','r',encoding='utf-8'))
14     if dic['count'] > 0:
15         dic['count']-=1
16         time.sleep(3)
17         json.dump(dic,open('db.txt','w',encoding='utf-8'))
18         print('<%s> 购票成功' %name)
19     else:
20         print('<%s> 购票失败' %name)
21 
22 def task(name,):
23     search(name)
24     # mutex.acquire()
25     get(name)
26     # mutex.release()
27 
28 if __name__ == '__main__':
29     # mutex=Lock()
30     for i in range(10):
31         p=Process(target=task,args=('路人%s' %i,))
32         p.start()
33         p.join()

互斥锁与join

 1 from multiprocessing import Queue
 2 
 3 
 4 q=Queue(3)
 5 
 6 q.put('hello')
 7 q.put({'a':1})
 8 q.put([3,3,3,])
 9 print(q.full())
10 
11 # q.put(4)
12 
13 print(q.get())
14 print(q.get())
15 print(q.get())
16 print(q.empty())
17 
18 print(q.get())

队列使用

 1 from multiprocessing import Process,Queue
 2 import time
 3 
 4 def producer(q):
 5     for i in range(10):
 6         res='包子%s' %i
 7         time.sleep(0.5)
 8         print('生产者生产了%s' %res)
 9 
10         q.put(res)
11 
12 def consumer(q):
13     while True:
14         res=q.get()
15         if res is None:break
16         time.sleep(1)
17         print('消费者吃了%s' % res)
18 
19 
20 
21 if __name__ == '__main__':
22     #容器
23     q=Queue()
24 
25     #生产者们
26     p1=Process(target=producer,args=(q,))
27     p2=Process(target=producer,args=(q,))
28     p3=Process(target=producer,args=(q,))
29 
30     #消费者们
31     c1=Process(target=consumer,args=(q,))
32     c2=Process(target=consumer,args=(q,))
33 
34     p1.start()
35     p2.start()
36     p3.start()
37     c1.start()
38     c2.start()
39 
40     p1.join()
41     p2.join()
42     p3.join()
43     q.put(None)
44     q.put(None)
45     print('主')

生产消费模型

 1 from multiprocessing import Process,JoinableQueue
 2 import time
 3 
 4 def producer(q):
 5     for i in range(2):
 6         res='包子%s' %i
 7         time.sleep(0.5)
 8         print('生产者生产了%s' %res)
 9 
10         q.put(res)
11     q.join()
12 
13 def consumer(q):
14     while True:
15         res=q.get()
16         if res is None:break
17         time.sleep(1)
18         print('消费者吃了%s' % res)
19         q.task_done()
20 
21 
22 if __name__ == '__main__':
23     #容器
24     q=JoinableQueue()
25 
26     #生产者们
27     p1=Process(target=producer,args=(q,))
28     p2=Process(target=producer,args=(q,))
29     p3=Process(target=producer,args=(q,))
30 
31     #消费者们
32     c1=Process(target=consumer,args=(q,))
33     c2=Process(target=consumer,args=(q,))
34     c1.daemon=True
35     c2.daemon=True
36 
37     p1.start()
38     p2.start()
39     p3.start()
40     c1.start()
41     c2.start()
42 
43 
44     p1.join()
45     p2.join()
46     p3.join()
47     print('主')

JoinableQueue

多线程

 1 # import time
 2 # import random
 3 # from threading import Thread
 4 #
 5 # def piao(name):
 6 #     print('%s piaoing' %name)
 7 #     time.sleep(random.randrange(1,5))
 8 #     print('%s piao end' %name)
 9 #
10 # if __name__ == '__main__':
11 #     t1=Thread(target=piao,args=('egon',))
12 #     t1.start()
13 #     print('主线程')
14 #
15 
16 
17 import time
18 import random
19 from threading import Thread
20 
21 class MyThread(Thread):
22     def __init__(self,name):
23         super().__init__()
24         self.name=name
25 
26     def run(self):
27         print('%s piaoing' %self.name)
28 
29         time.sleep(random.randrange(1,5))
30         print('%s piao end' %self.name)
31 
32 if __name__ == '__main__':
33     t1=MyThread('egon')
34     t1.start()
35     print('主')

开启线程的2种方式

 1 # 1、开进程的开销远大于开线程
 2 # import time
 3 # from threading import Thread
 4 # from multiprocessing import Process
 5 #
 6 # def piao(name):
 7 #     print('%s piaoing' %name)
 8 #     time.sleep(2)
 9 #     print('%s piao end' %name)
10 #
11 # if __name__ == '__main__':
12 #     # p1=Process(target=piao,args=('egon',))
13 #     # p1.start()
14 #
15 #     t1=Thread(target=piao,args=('egon',))
16 #     t1.start()
17 #     print('主线程')
18 
19 
20 
21 # 2、同一进程内的多个线程共享该进程的地址空间
22 # from threading import Thread
23 # from multiprocessing import Process
24 #
25 # n=100
26 # def task():
27 #     global n
28 #     n=0
29 #
30 # if __name__ == '__main__':
31 #     # p1=Process(target=task,)
32 #     # p1.start()
33 #     # p1.join()
34 #
35 #     t1=Thread(target=task,)
36 #     t1.start()
37 #     t1.join()
38 #
39 #     print('主线程',n)
40 
41 
42 # 3、瞅一眼pid
43 # from threading import Thread
44 # from multiprocessing import Process,current_process
45 # import os
46 #
47 # def task():
48 #     # print(current_process().pid)
49 #     print('子进程PID:%s  父进程的PID:%s' %(os.getpid(),os.getppid()))
50 #
51 # if __name__ == '__main__':
52 #     p1=Process(target=task,)
53 #     p1.start()
54 #
55 #     # print('主线程',current_process().pid)
56 #     print('主线程',os.getpid())
57 
58 
59 from threading import Thread
60 import os
61 
62 def task():
63     print('子线程:%s' %(os.getpid()))
64 
65 if __name__ == '__main__':
66     t1=Thread(target=task,)
67     t1.start()
68 
69     print('主线程',os.getpid())

进程与线程的区别

 1 from threading import Thread,currentThread,active_count,enumerate
 2 import time
 3 
 4 def task():
 5     print('%s is ruuning' %currentThread().getName())
 6     time.sleep(2)
 7     print('%s is done' %currentThread().getName())
 8 
 9 if __name__ == '__main__':
10     t=Thread(target=task,name='子线程1')
11     t.start()
12     # t.setName('儿子线程1')
13     # t.join()
14     # print(t.getName())
15     # currentThread().setName('主线程')
16     # print(t.isAlive())
17 
18 
19     # print('主线程',currentThread().getName())
20 
21     # t.join()
22     # print(active_count())
23     print(enumerate())

Thread对象的属性和方法

 1 # from threading import Thread
 2 # import time
 3 #
 4 # def sayhi(name):
 5 #     time.sleep(2)
 6 #     print('%s say hello' %name)
 7 #
 8 # if __name__ == '__main__':
 9 #     t=Thread(target=sayhi,args=('egon',))
10 #     # t.setDaemon(True) #必须在t.start()之前设置
11 #     t.daemon=True
12 #     t.start()
13 #
14 #     print('主线程')
15 #     print(t.is_alive())
16 #
17 
18 
19 from threading import Thread
20 import time
21 
22 def foo():
23     print(123)
24     time.sleep(1)
25     print("end123")
26 
27 def bar():
28     print(456)
29     time.sleep(3)
30     print("end456")
31 
32 if __name__ == '__main__':
33     t1=Thread(target=foo)
34     t2=Thread(target=bar)
35 
36     t1.daemon=True
37     t1.start()
38     t2.start()
39     print("main-------")
40 
41 
42     '''
43     123
44     456
45     main-------
46     end123
47     end456
48     
49     '''

守护线程

 1 #mutex
 2 from threading import Thread,Lock
 3 import time
 4 
 5 n=100
 6 
 7 def task():
 8     global n
 9     mutex.acquire()
10     temp=n
11     time.sleep(0.1)
12     n=temp-1
13     mutex.release()
14     
15 if __name__ == '__main__':
16     mutex=Lock()
17     t_l=[]
18     for i in range(100):
19         t=Thread(target=task)
20         t_l.append(t)
21         t.start()
22 
23     for t in t_l:
24         t.join()
25 
26     print('主',n)

互斥锁

 1 # 计算密集型：用多进程
 2 # from multiprocessing import Process
 3 # from threading import Thread
 4 # import os,time
 5 # def work():
 6 #     res=0
 7 #     for i in range(100000000):
 8 #         res*=i
 9 #
10 #
11 # if __name__ == '__main__':
12 #     l=[]
13 #     # print(os.cpu_count()) #本机为8核
14 #     start=time.time()
15 #     for i in range(8):
16 #         # p=Process(target=work) #耗时8s多
17 #         p=Thread(target=work) #耗时37s多
18 #         l.append(p)
19 #         p.start()
20 #     for p in l:
21 #         p.join()
22 #     stop=time.time()
23 #     print('run time is %s' %(stop-start))
24 
25 
26 # IO密集型：用多线程
27 from multiprocessing import Process
28 from threading import Thread
29 import threading
30 import os,time
31 
32 def work():
33     time.sleep(2)
34 
35 if __name__ == '__main__':
36     l=[]
37     # print(os.cpu_count()) #本机为4核
38     start=time.time()
39     for i in range(400):
40         # p=Process(target=work) #耗时2.697多,大部分时间耗费在创建进程上
41         p=Thread(target=work) #耗时2.02多
42         l.append(p)
43         p.start()
44     for p in l:
45         p.join()
46     stop=time.time()
47     print('run time is %s' %(stop-start))

GIL解释器锁

 1 # 死锁
 2 # from threading import Thread,Lock
 3 # import time
 4 #
 5 # mutexA=Lock()
 6 # mutexB=Lock()
 7 #
 8 # class MyThread(Thread):
 9 #     def run(self):
10 #         self.f1()
11 #         self.f2()
12 #
13 #     def f1(self):
14 #         mutexA.acquire()
15 #         print('%s 拿到了A锁' %self.name)
16 #
17 #         mutexB.acquire()
18 #         print('%s 拿到了B锁' %self.name)
19 #         mutexB.release()
20 #
21 #         mutexA.release()
22 #
23 #
24 #     def f2(self):
25 #         mutexB.acquire()
26 #         print('%s 拿到了B锁' % self.name)
27 #         time.sleep(0.1)
28 #
29 #         mutexA.acquire()
30 #         print('%s 拿到了A锁' % self.name)
31 #         mutexA.release()
32 #
33 #         mutexB.release()
34 #
35 # if __name__ == '__main__':
36 #     for i in range(10):
37 #         t=MyThread()
38 #         t.start()
39 
40 
41 # 互斥锁只能acquire一次
42 # from threading import Thread,Lock
43 #
44 # mutexA=Lock()
45 #
46 # mutexA.acquire()
47 # mutexA.release()
48 
49 
50 # 递归锁:可以连续acquire多次，每acquire一次计数器+1，只有计数为0时，才能被抢到acquire
51 from threading import Thread,RLock
52 import time
53 
54 mutexB=mutexA=RLock()
55 
56 class MyThread(Thread):
57     def run(self):
58         self.f1()
59         self.f2()
60 
61     def f1(self):
62         mutexA.acquire()
63         print('%s 拿到了A锁' %self.name)
64 
65         mutexB.acquire()
66         print('%s 拿到了B锁' %self.name)
67         mutexB.release()
68 
69         mutexA.release()
70 
71 
72     def f2(self):
73         mutexB.acquire()
74         print('%s 拿到了B锁' % self.name)
75         time.sleep(7)
76 
77         mutexA.acquire()
78         print('%s 拿到了A锁' % self.name)
79         mutexA.release()
80 
81         mutexB.release()
82 
83 if __name__ == '__main__':
84     for i in range(10):
85         t=MyThread()
86         t.start()

死锁和递归锁

 1 from threading import Thread,Semaphore,currentThread
 2 import time,random
 3 
 4 sm=Semaphore(3)
 5 
 6 def task():
 7     # sm.acquire()
 8     # print('%s in' %currentThread().getName())
 9     # sm.release()
10     with sm:
11         print('%s in' %currentThread().getName())
12         time.sleep(random.randint(1,3))
13 
14 
15 if __name__ == '__main__':
16     for i in range(10):
17         t=Thread(target=task)
18         t.start()

信号量

 1 # from threading import Thread,Event
 2 # import time
 3 #
 4 # event=Event()
 5 # # event.wait()
 6 # # event.set()
 7 #
 8 #
 9 # def student(name):
10 #     print('学生%s 正在听课' %name)
11 #     event.wait(2)
12 #     print('学生%s 课间活动' %name)
13 #
14 #
15 # def teacher(name):
16 #     print('老师%s 正在授课' %name)
17 #     time.sleep(7)
18 #     event.set()
19 #
20 #
21 # if __name__ == '__main__':
22 #     stu1=Thread(target=student,args=('alex',))
23 #     stu2=Thread(target=student,args=('wxx',))
24 #     stu3=Thread(target=student,args=('yxx',))
25 #     t1=Thread(target=teacher,args=('egon',))
26 #
27 #     stu1.start()
28 #     stu2.start()
29 #     stu3.start()
30 #     t1.start()
31 
32 
33 
34 from threading import Thread,Event,currentThread
35 import time
36 
37 event=Event()
38 
39 def conn():
40     n=0
41     while not event.is_set():
42         if n == 3:
43             print('%s try too many times' %currentThread().getName())
44             return
45         print('%s try %s' %(currentThread().getName(),n))
46         event.wait(0.5)
47         n+=1
48 
49     print('%s is connected' %currentThread().getName())
50 
51 
52 def check():
53     print('%s is checking' %currentThread().getName())
54     time.sleep(5)
55     event.set()
56 
57 
58 if __name__ == '__main__':
59     for i in range(3):
60         t=Thread(target=conn)
61         t.start()
62     t=Thread(target=check)
63     t.start()

Event事件

 1 # from threading import Timer
 2 #
 3 # def task(name):
 4 #     print('hello %s' %name)
 5 #
 6 #
 7 # t=Timer(5,task,args=('egon',))
 8 # t.start()
 9 
10 from threading import Timer
11 import random
12 
13 class Code:
14     def __init__(self):
15         self.make_cache()
16 
17     def make_cache(self,interval=5):
18         self.cache=self.make_code()
19         print(self.cache)
20         self.t=Timer(interval,self.make_cache)
21         self.t.start()
22 
23     def make_code(self,n=4):
24         res=''
25         for i in range(n):
26             s1=str(random.randint(0,9))
27             s2=chr(random.randint(65,90))
28             res+=random.choice([s1,s2])
29         return res
30 
31     def check(self):
32         while True:
33             code=input('请输入你的验证码>>: ').strip()
34             if code.upper() == self.cache:
35                 print('验证码输入正确')
36                 self.t.cancel()
37                 break
38 
39 
40 obj=Code()
41 obj.check()

定时器

 1 import queue
 2 
 3 # q=queue.Queue(3) #先进先出->队列
 4 #
 5 # q.put('first')
 6 # q.put(2)
 7 # q.put('third')
 8 # # q.put(4)
 9 # # q.put(4,block=False) #q.put_nowait(4)
10 # # q.put(4,block=True,timeout=3)
11 #
12 #
13 # #
14 # print(q.get())
15 # print(q.get())
16 # print(q.get())
17 # # print(q.get(block=False)) #q.get_nowait()
18 # # print(q.get_nowait())
19 #
20 # # print(q.get(block=True,timeout=3))
21 
22 
23 # q=queue.LifoQueue(3) #后进先出->堆栈
24 # q.put('first')
25 # q.put(2)
26 # q.put('third')
27 #
28 # print(q.get())
29 # print(q.get())
30 # print(q.get())
31 
32 #
33 # q=queue.PriorityQueue(3) #优先级队列
34 #
35 # q.put((10,'one'))
36 # q.put((40,'two'))
37 # q.put((30,'three'))
38 #
39 # print(q.get())
40 # print(q.get())
41 # print(q.get())

线程queue

线程池&进程池

# from concurrent.futures import ProcessPoolExecutor,ThreadPoolExecutor
# import os,time,random
#
# def task(name):
#     print('name:%s pid:%s run' %(name,os.getpid()))
#     time.sleep(random.randint(1,3))
#
#
# if __name__ == '__main__':
#     # pool=ProcessPoolExecutor(4)
#     pool=ThreadPoolExecutor(5)
#
#     for i in range(10):
#         pool.submit(task,'egon%s' %i)
#
#     pool.shutdown(wait=True)
#
#
#     print('主')


from concurrent.futures import ProcessPoolExecutor,ThreadPoolExecutor
from threading import currentThread
import os,time,random

def task():
    print('name:%s pid:%s run' %(currentThread().getName(),os.getpid()))
    time.sleep(random.randint(1,3))


if __name__ == '__main__':
    pool=ThreadPoolExecutor(5)

    for i in range(10):
        pool.submit(task,)

    pool.shutdown(wait=True)


    print('主')

进程池-线程池的开启

 1 #提交任务的两种方式
 2 #1、同步调用:提交完任务后，就在原地等待任务执行完毕，拿到结果，再执行下一行代码,导致程序是串行执行
 3 #
 4 # from concurrent.futures import ThreadPoolExecutor
 5 # import time
 6 # import random
 7 #
 8 # def la(name):
 9 #     print('%s is laing' %name)
10 #     time.sleep(random.randint(3,5))
11 #     res=random.randint(7,13)*'#'
12 #     return {'name':name,'res':res}
13 #
14 # def weigh(shit):
15 #     name=shit['name']
16 #     size=len(shit['res'])
17 #     print('%s 拉了 《%s》kg' %(name,size))
18 #
19 #
20 # if __name__ == '__main__':
21 #     pool=ThreadPoolExecutor(13)
22 #
23 #     shit1=pool.submit(la,'alex').result()
24 #     weigh(shit1)
25 #
26 #     shit2=pool.submit(la,'wupeiqi').result()
27 #     weigh(shit2)
28 #
29 #     shit3=pool.submit(la,'yuanhao').result()
30 #     weigh(shit3)
31 
32 
33 #2、异步调用：提交完任务后，不地等待任务执行完毕，
34 
35 from concurrent.futures import ThreadPoolExecutor
36 import time
37 import random
38 
39 def la(name):
40     print('%s is laing' %name)
41     time.sleep(random.randint(3,5))
42     res=random.randint(7,13)*'#'
43     return {'name':name,'res':res}
44 
45 
46 def weigh(shit):
47     shit=shit.result()
48     name=shit['name']
49     size=len(shit['res'])
50     print('%s 拉了 《%s》kg' %(name,size))
51 
52 
53 if __name__ == '__main__':
54     pool=ThreadPoolExecutor(13)
55 
56     pool.submit(la,'alex').add_done_callback(weigh)
57 
58     pool.submit(la,'wupeiqi').add_done_callback(weigh)
59 
60     pool.submit(la,'yuanhao').add_done_callback(weigh)

异步调用&回调机制

 1 from concurrent.futures import ThreadPoolExecutor
 2 import requests
 3 import time
 4 
 5 def get(url):
 6     print('GET %s' %url)
 7     response=requests.get(url)
 8     time.sleep(3)
 9     return {'url':url,'content':response.text}
10 
11 
12 def parse(res):
13     res=res.result()
14     print('%s parse res is %s' %(res['url'],len(res['content'])))
15 
16 
17 if __name__ == '__main__':
18     urls=[
19         'http://www.cnblogs.com/linhaifeng',
20         'https://www.python.org',
21         'https://www.openstack.org',
22     ]
23 
24     pool=ThreadPoolExecutor(2)
25 
26     for url in urls:
27         pool.submit(get,url).add_done_callback(parse)

线程池示例

协程

 1 #并发执行
 2 import time
 3 
 4 def producer():
 5     g=consumer()
 6     next(g)
 7     for i in range(10000000):
 8         g.send(i)
 9 
10 
11 
12 def consumer():
13     while True:
14         res=yield
15 
16 
17 start_time=time.time()
18 producer()
19 stop_time=time.time()
20 print(stop_time-start_time)
21 
22 
23 
24 #串行
25 import time
26 
27 def producer():
28     res=[]
29     for i in range(10000000):
30         res.append(i)
31     return res
32 
33 
34 def consumer(res):
35     pass
36 
37 
38 start_time=time.time()
39 res=producer()
40 consumer(res)
41 stop_time=time.time()
42 print(stop_time-start_time)

协程

 1 #pip3 install greenlet
 2 from greenlet import greenlet
 3 import time
 4 
 5 def eat(name):
 6     print('%s eat 1' %name)
 7     time.sleep(10)
 8     g2.switch('egon')
 9     print('%s eat 2' %name)
10     g2.switch()
11 
12 def play(name):
13     print('%s play 1' %name )
14     g1.switch()
15     print('%s play 2' %name )
16 
17 
18 g1=greenlet(eat)
19 g2=greenlet(play)
20 
21 g1.switch('egon')

greenlet模块

 1 #pip3 install gevent
 2 # from gevent import monkey;monkey.patch_all()
 3 # import gevent
 4 # import time
 5 #
 6 #
 7 # def eat(name):
 8 #     print('%s eat 1' % name)
 9 #     time.sleep(3)
10 #     print('%s eat 2' % name)
11 #
12 #
13 # def play(name):
14 #     print('%s play 1' % name)
15 #     time.sleep(4)
16 #     print('%s play 2' % name)
17 #
18 #
19 # start_time=time.time()
20 # g1=gevent.spawn(eat,'egon')
21 # g2=gevent.spawn(play,'alex')
22 #
23 #
24 # g1.join()
25 # g2.join()
26 # stop_time=time.time()
27 # print(stop_time-start_time)
28 
29 
30 from gevent import monkey;monkey.patch_all()
31 import gevent
32 import time
33 
34 
35 def eat(name):
36     print('%s eat 1' % name)
37     time.sleep(3)
38     print('%s eat 2' % name)
39 
40 
41 def play(name):
42     print('%s play 1' % name)
43     time.sleep(4)
44     print('%s play 2' % name)
45 
46 
47 g1=gevent.spawn(eat,'egon')
48 g2=gevent.spawn(play,'alex')
49 
50 
51 # time.sleep(5)
52 
53 
54 # g1.join()
55 # g2.join()
56 
57 gevent.joinall([g1,g2])

gevent模块（自动切换）

作者：华王博客：https://www.cnblogs.com/huahuawang/

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原文地址：https://www.cnblogs.com/huahuawang/p/14725519.html

第五篇 进程&线程&协程

第五篇进程&线程&协程