Python 스레드 풀에 대한 추가 이해

# !/usr/bin/env python
# -*- coding:utf-8 -*-
# ref_blog:http://www.open-open.com/home/space-5679-do-blog-id-3247.html
import Queue
import threading
import time
class WorkManager(object):
    def __init__(self, work_num=1000,thread_num=2):
        self.work_queue = Queue.Queue()
        self.threads = []
        self.__init_work_queue(work_num)
        self.__init_thread_pool(thread_num)
    """
        初始化线程
    """
    def __init_thread_pool(self,thread_num):
        for i in range(thread_num):
            self.threads.append(Work(self.work_queue))
    """
        初始化工作队列
    """
    def __init_work_queue(self, jobs_num):
        for i in range(jobs_num):
            self.add_job(do_job, i)
    """
        添加一项工作入队
    """
    def add_job(self, func, *args):
        self.work_queue.put((func, list(args)))#任务入队，Queue内部实现了同步机制
    """
        检查剩余队列任务
    """
    def check_queue(self):
        return self.work_queue.qsize()
    """
        等待所有线程运行完毕
    """ 
    def wait_allcomplete(self):
        for item in self.threads:
            if item.isAlive():item.join()
class Work(threading.Thread):
    def __init__(self, work_queue):
        threading.Thread.__init__(self)
        self.work_queue = work_queue
        self.start()
    def run(self):
        #死循环，从而让创建的线程在一定条件下关闭退出
        while True:
            try:
                do, args = self.work_queue.get(block=False)#任务异步出队，Queue内部实现了同步机制
                do(args)
                self.work_queue.task_done()#通知系统任务完成
            except Exception,e:
                print str(e)
                break
#具体要做的任务
def do_job(args):
    print args
    time.sleep(0.1)#模拟处理时间
    print threading.current_thread(), list(args)
if __name__ == '__main__':
    start = time.time()
    work_manager =  WorkManager(10, 2)#或者work_manager =  WorkManager(10000, 20)
    work_manager.wait_allcomplete()
    end = time.time()
    print "cost all time: %s" % (end-start)