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, n
time.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, n
time.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=False
pass
print 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 time
def 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 time
def printworld():
for i in range(5):
if w_lock.acquire(): ＃申请world锁，if True为真
print 'world',time.ctime() ＃打印world
h_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hello
w_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 python
import thread
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()
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 threading
In [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 python
import threading
import time
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()
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, n
time.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:utf8
import threading
import time
def func(name, i):
for n in xrange(i):
print name, n
time.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 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'
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：
先申请h_lock锁，即h_lock.acquire()
然后输出hello，即print 'hello',
最后释放w_lock锁，即w_lock.release()
执行world线程时也是3步：
申请w_lock锁，即w_lock.acquire()
输出world，即print 'world'
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 python
import threading
import time
class MyThread(threading.Thread):
def __init__(self):
threading.Thread.__init__(self)
def run(self):
global counter
time.sleep(1)
mutex.acquire() ＃获得锁
counter +=1
print "I am %s, set counter:%s" %(self.name,counter)
mutex.release() ＃释放锁
if __name__ == '__main__':
counter = 0
mutex = 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:15
I 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