python - 如何獲得由特定類啓動的活動線程的數量？

Question

代碼如下所示：

class workers1(Thread): 
... def __init__(self): 
...  Thread.__init__(self) 
... def run(self): 
...  ...do some stuff 

class workers2(Thread): 
... def __init__(self): 
...  Thread.__init__(self) 
... def run(self): 
...  ...do some stuff 


if __name__ == "__main__": 
... start workers 
while True: 
    print "Number of threads active", threading.activeCount() 
    print "Number of worker1 threads", ?????, "Number of worker2 threads", ????? 

有沒有辦法讓線程借原班活躍的號碼嗎？

Answer 1

這是Doug Hellman的multiprocessing ActivePool example code（使用線程）的一個小修改。這個想法是讓你的員工自己註冊一個游泳池，註銷自己，當他們完成，使用threading.Lock協調池的活動列表的修改：

import threading 
import time 
import random 

class ActivePool(object): 
    def __init__(self): 
     super(ActivePool, self).__init__() 
     self.active=[] 
     self.lock=threading.Lock() 
    def makeActive(self, name): 
     with self.lock: 
      self.active.append(name) 
    def makeInactive(self, name): 
     with self.lock: 
      self.active.remove(name) 
    def numActive(self): 
     with self.lock: 
      return len(self.active) 
    def __str__(self): 
     with self.lock: 
      return str(self.active) 
def worker(pool): 
    name=threading.current_thread().name 
    pool.makeActive(name) 
    print 'Now running: %s' % str(pool) 
    time.sleep(random.randint(1,3)) 
    pool.makeInactive(name) 

if __name__=='__main__': 
    poolA=ActivePool() 
    poolB=ActivePool()  
    jobs=[] 
    for i in range(5): 
     jobs.append(
      threading.Thread(target=worker, name='A{0}'.format(i), 
          args=(poolA,))) 
     jobs.append(
      threading.Thread(target=worker, name='B{0}'.format(i), 
          args=(poolB,))) 
    for j in jobs: 
     j.daemon=True 
     j.start() 
    while threading.activeCount()>1: 
     for j in jobs: 
      j.join(1) 
      print 'A-threads active: {0}, B-threads active: {1}'.format(
       poolA.numActive(),poolB.numActive()) 

產量

Now running: ['A0'] 
Now running: ['B0'] 
Now running: ['A0', 'A1'] 
Now running: ['B0', 'B1'] 
Now running: ['A0', 'A1', 'A2'] 
Now running: ['B0', 'B1', 'B2'] 
Now running: ['A0', 'A1', 'A2', 'A3'] 
Now running: ['B0', 'B1', 'B2', 'B3'] 
Now running: ['A0', 'A1', 'A2', 'A3', 'A4'] 
Now running: ['B0', 'B1', 'B2', 'B3', 'B4'] 
A-threads active: 4, B-threads active: 5 
A-threads active: 2, B-threads active: 5 
A-threads active: 0, B-threads active: 3 
A-threads active: 0, B-threads active: 3 
A-threads active: 0, B-threads active: 3 
A-threads active: 0, B-threads active: 3 
A-threads active: 0, B-threads active: 3 
A-threads active: 0, B-threads active: 0 
A-threads active: 0, B-threads active: 0 
A-threads active: 0, B-threads active: 0 

Answer 2

您可以爲每個班級使用信號量並獲得計數：請參閱link。