The implementation method of multithreading thread and threading in Python

Anyone who learns python should know that Python is a thread that supports multithreading and is native. This article is mainly through the thread and threading these two modules to achieve multithreading.

Python's thread module is a relatively low-level module, Python's threading module is a thread to do some packaging, can be more convenient to use.

What you need to mention here is that Python's support for threading is not perfect enough to take advantage of multiple CPUs, but the next version of Python has already been considered to improve this, let's wait and see.

Threading module is mainly for the operation of some threads of the object, the creation of a class called Thread.

In general, there are two modes of using threads, one is to create a function to execute the thread, pass the function into the thread object, let it execute, and the other is to inherit from thread directly, create a new class, and put the code executed by the thread into the new class.

Let's take a look at both of these approaches.

One, Python thread implementation multithreading

#-*-encoding:gb2312-*-import String, threading, Time Def Thread_main (a):  global Count, mutex  # get thread name  Threa Dname = Threading.currentthread (). GetName ()   for x in xrange (0, Int (a)):    # Get lock    Mutex.acquire ()    count = Count + 1    # release lock    mutex.release ()    print ThreadName, x, Count    time.sleep (1) def main (num):  Global Count, mutex  threads = []   count = 1  # Creates a lock  mutex = Threading. Lock ()  # First creates a thread object  for x in xrange (0, num):    threads.append (Threading. Thread (Target=thread_main, args= ()))  # starts all threads  for T in Threads:    T.start ()  # Waiting for all child threads to exit in the main thread For  T in Threads:    t.join ()   if __name__ = = ' __main__ ':  num = 4  # Create 4 threads  Main (4)

Second, Python threading realize multithreading

#-*-encoding:gb2312-*-import Threadingimport Time Class Test (threading. Thread):  def __init__ (self, num):    threading. Thread.__init__ (self)    self._run_num = num   def run (self):    global count, mutex    ThreadName = Threading.currentthread (). GetName ()     for x in xrange (0, int (self._run_num)):      mutex.acquire ()      count = Count + 1      mutex.release ()      print ThreadName, x, Count      time.sleep (1) if __name__ = = ' __main__ ':  Global Count, mutex  threads = []  num = 4  count = 1  # Create lock  Mutex = Threading. Lock ()  # Create thread object for  x in xrange (0, num):    threads.append (Test)  # Start thread for T in  Threads:    T.start ()  # waits for the child thread to end for the  T in Threads:    

It is believed that the Python multithreaded instance described in this paper can be used for reference in Python programming.

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