python下线程以及锁

1、python多线程

 1 #encoding=utf-8
 2 """
 3 python多线程，并非真正意义上的多线程
 4 全局锁：在指定时间里，有且只有一个线程在运行
 5
 6
 7 """
 8 import threading
 9 import time
10
11 def test(p):
12     time.sleep(0.1)
13     print p
14
15 # a = threading.Thread(target=test)
16 # b = threading.Thread(target=test)
17 # a.start()
18 # b.start()
19 #
20 # a.join()
21 # b.join()
22
23 lst =[]
24 for i in xrange(0, 15):
25     th = threading.Thread(target=test, args=[i])
26     lst.append(th)
27
28 for i in lst:
29     i.start()
30
31
32 for i in lst:
33     i.join()
34 print "primary thread end!!!"

2、python下的锁

 1 #encoding=utf-8
 2
 3 """
 4 1、python全局锁：GLT
 5   python多线程在任意时刻下只有一个线程在运行，它是线程安全的
 6 """
 7
 8 import threading
 9
10 num = 0
11 def t():
12     global num
13     num +=1
14     print num
15
16 for i in xrange(0, 10):
17     d = threading.Thread(target=t)
18     d.start()
19
20
21 import time
22 b_time = time.time()
23 _a = threading.Thread(target=t)
24 _b = threading.Thread(target=t)
25 _a.start()
26 _b.start()
27
28 _a.join()
29 _b.join()
30
31 print time.time()-b_time
32
33 """
34 加锁：acquire()
35 解锁：release()
36 RLock()可重入锁
37
38
39 """
40 import threading
41 mlock = threading.Lock()
42 #mlock = threading.RLock()
43
44 num_01 = 0
45 def a():
46     global num_01
47     mlock.acquire()
48     num_01 += 1
49     mlock.release()
50     print num_01
51
52 for i in xrange(0, 10):
53     d = threading.Thread(target=a)
54     d.start()
55