多线程介绍和多线程模块

线程的特点：

线程的生命周期

开始

运行

结束

线程的退出：

进程执行完成

线程的退出方法

python的系统推出

模块函数

start_new_thread(func, args) #(func,(name,i))

allocate_lock()

exit()

[root@133 managehosts]# vim thread01.py #!/usr/bin/env python
#encoding:utf8
import thread
import time
def func(name , i):for n in xrange(i):print name, ntime.sleep(1)thread.start_new_thread(func,('声音', 3)) #(func,(name , i))
thread.start_new_thread(func,('画面', 3))time.sleep(3)
[root@133 managehosts]# python thread01.py
声音 0
画面 0
声音 1
画面 1
声音 2
画面 2

LockType对象方法

lock= thread.allocate_lock() 生成锁对象

lock.acquire()   加锁

lock.locked()     查看锁状态

lock.release()    多线程调度释放锁，使用前线程必须已经获得锁定，否则将抛出异常

[root@133 managehosts]# vim thread01.py #!/usr/bin/env python
#encoding:utf8
import thread
import time
def func(name , i, l):for n in xrange(i):print name, ntime.sleep(1)l.release()  ＃release解锁lock = thread.allocate_lock() ＃申请一把锁
lock.acquire()  ＃获取并使用这把锁thread.start_new_thread(func,('声音', 5, lock))
thread.start_new_thread(func,('画面', 5, lock))while lock.locked(): #这是主进程，lock.locked=True，执行pass,主进程一直处于锁定状态，线程执行，直到线程执行完毕，释放锁，lock.locked=Falsepassprint lock.locked() #解锁后，值为False
print "Exit main process"[root@133 managehosts]# python thread01.py
声音 画面 00画面 1
声音 1
画面 2
声音 2
画面 3
声音 3
画面 4
声音 4
False
Exit main process[root@133 managehosts]# vim thread02.py
#!/usr/bin/env python
import thread
import timedef printworld():for i in range(5):if w_lock.acquire():print 'world',time.ctime()h_lock.release()h_lock = thread.allocate_lock()
w_lock = thread.allocate_lock()thread.start_new_thread(printworld, ())w_lock.acquire()
for i in range(5):if h_lock.acquire():print 'hello',w_lock.release()time.sleep(1)
[root@133 managehosts]# python thread02.py
hello world Fri Feb 10 20:26:51 2017
hello world Fri Feb 10 20:26:51 2017
hello world Fri Feb 10 20:26:51 2017
hello world Fri Feb 10 20:26:51 2017
hello world Fri Feb 10 20:26:51 2017[root@133 managehosts]# vim thread02.py
#!/usr/bin/env python
import thread
import timedef printworld():for i in range(5):if w_lock.acquire():  ＃申请world锁，if True为真print 'world',time.ctime() ＃打印worldh_lock.release()   ＃释放hello锁h_lock = thread.allocate_lock()
w_lock = thread.allocate_lock()thread.start_new_thread(printworld, ()) ＃开启的线程，和主进程并列执行。w_lock.acquire()   ＃获得world锁
for i in range(5):if h_lock.acquire(): ＃申请hello锁，if True为真print 'hello',   ＃打印hellow_lock.release() ＃释放world锁while h_lock.locked(): #这是主进程，直到hello打印5次后才释放。pass[root@133 managehosts]# python thread02.py
hello world Fri Feb 10 20:29:48 2017
hello world Fri Feb 10 20:29:48 2017
hello world Fri Feb 10 20:29:48 2017
hello world Fri Feb 10 20:29:48 2017
hello world Fri Feb 10 20:29:48 2017

申请了锁之后，会执行thread.start_new_thread(func,('声音',5,lock))和thread.start_new_thread(func,('画面',5,lock))这两行代码的。

执行他们的时候，同时也会执行主进程里的while的。主进程与这两个线程是同时执行的。为了不让线程退出，所以在主进程里有while来判断锁是不是已经释放了，如果是释放了，说明线程执行完了。

使用主线程控制，线程打印hello和world

[root@133 managehosts]# vim thread03.py +22#!/usr/bin/env pythonimport thread
import timedef hello():for i in xrange(5):h_lock.acquire()print 'hello',w_lock.release()def world():for i in xrange(5):w_lock.acquire()print 'world',time.ctime()h_lock.release() lock.release()＃释放主线程的的锁lock = thread.allocate_lock() #为主进程申请锁
lock.acquire()      ＃主进程获得锁h_lock = thread.allocate_lock()  ＃为hello线程申请一把锁
w_lock = thread.allocate_lock()  ＃为world线程申请一把锁
w_lock.acquire()                 ＃world线程获取锁
thread.start_new_thread(hello,())＃启动线程hello
thread.start_new_thread(world,())＃启动线程world#time.sleep(1)
while lock.locked():   ＃当主线程的锁的状态为true时 pass               ＃什么都不做＃hello 和 world 的两个线程是同时运行的
[root@133 managehosts]# python thread03.py
hello world Tue Feb 14 14:59:11 2017
hello world Tue Feb 14 14:59:11 2017
hello world Tue Feb 14 14:59:11 2017
hello world Tue Feb 14 14:59:11 2017
hello world Tue Feb 14 14:59:11 2017

从脚本的执行顺序，hello()这个函数先执行，输出hello，
然后把world的锁释放（w_lock.release()）。
world()函数获得锁，输出world，然后把hello的锁释放。
必须释放对方的锁，对方才能获得锁（h_lock.acquire()），如果对方的锁没有被释放，那么对方再想获得锁是不成功的，会一直处于阻塞状态，直到锁被释放。

hello()函数第一次获得了锁资源（h_lock.acquire()），打印了hello，接着释放了world的锁资源（w_lock.release()）。
world()函数获得了锁资源（w_lock.acquire()），打印了world，接着释放了hello的锁资源（h_lock.release()）。
由于hello的锁资源被释放了，hello函数里又获得了锁资源，接着第二次打印hello。
也就是说哪个函数或得了锁资源，就会打印相应的信息。
锁资源只有被释放了，下一次才能获得，即已经获得了锁资源，不能再次获得，所以在hello函数里释放world的锁资源，在world函数里才能获得锁资源。
这样反反复复，就打印了hello world。

threading

threading不需要进程的控制来控制线程

threading.Thread:类

成员方法：

start() 启动线程

run()   可以重写

join()   阻塞

getName()

setName()

isDaemon()判断线程是否随主线程一起结束

setDaemon设置线程与主线程一起结束

In [1]: import threadingIn [2]: help(threading.Thread)
Help on class Thread in module threading:
class Thread(_Verbose)|  Method resolution order:|      Thread|      _Verbose|      __builtin__.object|  |  Methods defined here:|  |  __init__(self, group=None, target=None, name=None, args=(), kwargs=None, verbose=None)

[root@133 managehosts]# vim threading01.py#!/usr/bin/env pythonimport threading
import timedef func():print 'hello',time.ctime()time.sleep(1)if __name__ == '__main__':for i in xrange(10):t = threading.Thread(target=func, args =())t.start()
print 'complete'[root@133 managehosts]# python threading01.py
hello Tue Feb 14 15:42:10 2017 ＃瞬间打印10行
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
complete

如果添加t.join,则会阻塞，每秒打印一次，上一个阻塞执行完才会执行下一个

def func():print 'hello',time.ctime()time.sleep(1)if __name__ == '__main__':for i in xrange(10):t = threading.Thread(target=func, args =())t.start()t.join()
[root@133 managehosts]# python threading01.py
hello Tue Feb 14 15:42:10 2017 #每隔一秒打印一次
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
hello Tue Feb 14 15:42:10 2017
complete

[root@133 managehosts]# vim threading02.py
#!/usr/bin/env python
#encoding:utf8
import threading
import time
def func(name, i):for n in xrange(i):print name, ntime.sleep(1)
t1 = threading.Thread(target=func, args=('声音',3))
t2 = threading.Thread(target=func, args=('画面',3))
t1.start()
t2.start()[root@133 managehosts]# python threading02.py
声音 0
画面 0
声音 1
画面 1
声音 2
画面 2如果添加一个t1.join()，则会先打印t1，然后再打印t2
t1.start()
t1.join()
t2.start()结果变为：
[root@133 managehosts]# python threading02.py
声音 0
声音 1
声音 2
画面 0
画面 1
画面 2

t1.setDaemon(True) 设置t1线程和主进程一起退出

[root@133 managehosts]# vim threading02.py #!/usr/bin/env python
#encoding:utf8import threading
import timedef func(name, i):for n in xrange(i):print name, ntime.sleep(1)t1 = threading.Thread(target=func, args=('声音',3))
t2 = threading.Thread(target=func, args=('画面',3))t1.setDaemon(True) ＃设置t1线程和主进程一起退出
t1.start()         ＃开启t1线程，打印一次就会退出，因为主进程已经退出
t2.setDaemon(True)
t2.start()[root@133 managehosts]# python threading02.py
声音 0
画面 0

互斥锁

[root@133 managehosts]# pwd
/opt/python/managehosts
[root@133 managehosts]# cat threading07.py
#!/usr/bin/env python
import threading
import time
def hello():for i in xrange(5):h_lock.acquire()print 'hello',w_lock.release()def world():for i in xrange(5):w_lock.acquire()print 'world',time.ctime()h_lock.release()h_lock =  threading.Lock()
w_lock = threading.Lock()w_lock.acquire()t1 = threading.Thread(target=hello, args=())
t2 = threading.Thread(target=world, args=())t1.start()
t2.start()[root@133 managehosts]# python threading07.py
hello world Wed Mar 29 11:51:59 2017
hello world Wed Mar 29 11:51:59 2017
hello world Wed Mar 29 11:51:59 2017
hello world Wed Mar 29 11:51:59 2017
hello world Wed Mar 29 11:51:59 2017

#!/usr/bin/python
import thread
import timedef hello():for i in xrange(5):h_lock.acquire()print 'hello',w_lock.release()def world():for i in xrange(5):w_lock.acquire()print 'world'h_lock.release()lock.release()lock = thread.allocate_lock()
lock.acquire()
h_lock = thread.allocate_lock()
w_lock = thread.allocate_lock()
w_lock.acquire()
thread.start_new_thread(hello, ())
thread.start_new_thread(world, ())while lock.locked():    pass

程序执行开两个线程，即hello和world。

执行hello线程时，只有3步：

1. 先申请h_lock锁，即h_lock.acquire()

2. 然后输出hello，即print 'hello',

3. 最后释放w_lock锁，即w_lock.release()

执行world线程时也是3步：

1. 申请w_lock锁，即w_lock.acquire()

2. 输出world，即print 'world'

3. 释放h_lock锁，即h_lock.release()

线程是同时执行的，为什么hello和world会交替输出，没有先输出world？

在主线程里，申请了w_lock锁，即26行的w_lock.acquire()，所以在world()函数里的w_lock.acquire()一直

处于阻塞状态，意味着print 'world'这一行是不会执行的，直到hello()函数里把w_lock释放，即w_lock.release()

所以在每个函数里都有释放对方的锁，这样对方就把自己要输出的内容执行了。

最后world函数里的循环执行完了，释放lock这个锁，这样这个主进程也结束了。

[root@133 managehosts]# cat threading08.py
#!/usr/bin/env pythonimport threadingimport timeclass MyThread(threading.Thread):def __init__(self):threading.Thread.__init__(self)def run(self):global countertime.sleep(1)mutex.acquire() ＃获得锁counter +=1print "I am %s, set counter:%s" %(self.name,counter)mutex.release() ＃释放锁if __name__ == '__main__':counter = 0mutex = threading.Lock() #分配锁for i in xrange(300):t = MyThread()t.start()[root@133 managehosts]# python threading08.py
I am Thread-1, set counter:1
I am Thread-2, set counter:2
I am Thread-3, set counter:3
I am Thread-4, set counter:4
I am Thread-5, set counter:5
I am Thread-6, set counter:6
I am Thread-7, set counter:7
I am Thread-8, set counter:8
I am Thread-9, set counter:9
I am Thread-10, set counter:10
I am Thread-11, set counter:11
I am Thread-12, set counter:12
I am Thread-13, set counter:13
I am Thread-14, set counter:14
I am Thread-15, set counter:15I am Thread-284, set counter:282
I am Thread-283, set counter:283
I am Thread-282, set counter:284
I am Thread-285, set counter:285
I am Thread-287, set counter:286
I am Thread-286, set counter:287
I am Thread-288, set counter:288
I am Thread-289, set counter:289
I am Thread-290, set counter:290
I am Thread-293, set counter:291
I am Thread-292, set counter:292
I am Thread-291, set counter:293
I am Thread-295, set counter:294
I am Thread-296, set counter:295
I am Thread-297, set counter:296
I am Thread-294, set counter:297
I am Thread-298, set counter:298
I am Thread-299, set counter:299
I am Thread-300, set counter:300