[Python] thread

개요

• 공식 문서
• daemon 플래그
  • 데몬 스레드 여부 설정
  • True일 경우 데몬 스레드만 남았을 때 프로그램 즉시 종료
  • False일 경우 스레드가 종료될 때까지 대기

예제

• 코드

  •  import threading
     import time
            
            
     class Thread(threading.Thread):
            
         def __init__(self, lock, count, result):
             threading.Thread.__init__(self)
            
             self.lock = lock
             self.count = count
             self.result = result
            
         def run(self):
             self.lock.acquire()
            
             print('threading.get_native_id() :', threading.get_native_id())
             print('threading.current_thread().name :',
                   threading.current_thread().name)
             print('threading.get_ident() :', threading.get_ident(), '\n')
            
             for i in range(0, self.count):
                 self.result[0] += 1
            
             self.lock.release()
            
            
     class Test:
            
         def __init__(self):
             self.lock = threading.Lock()
             self.count = 100000
             self.result = 0
            
         def worker_1(self, arg1, arg2):
             print('arg1 :', arg1)
             print('arg2 :', arg2)
            
             with self.lock:
                 for i in range(0, self.count):
                     self.result += 1
            
         def worker_2(self, second):
             print('\t~~~', threading.current_thread().name, 'start ~~~')
             time.sleep(second)
             print('\t~~~', threading.current_thread().name, 'end ~~~')
            
         def run_1(self):
             threads = []
            
             for i in range(0, 2):
                 t = threading.Thread(target=self.worker_1, args=(1, 2))
                 t.start()
                 threads.append(t)
            
             for t in threads:
                 t.join()
            
             print('self.result :', self.result)
            
         def run_2(self):
             t1 = threading.Thread(target=self.worker_2,
                                   name='dameon=False',
                                   args=(1, ))
             t1.start()
            
             t2 = threading.Thread(target=self.worker_2,
                                   name='daemon=True',
                                   args=(2, ),
                                   daemon=True)
             t2.start()
            
            
     def worker(lock, count, result):
         with lock:
             for i in range(0, count):
                 result[0] += 1
            
            
     def way_1():
         print('----- way_1 start -----')
            
         threads = []
            
         lock = threading.Lock()
         count = 100000
         result = [0]
            
         for i in range(0, 2):
             t = Thread(lock, count, result)
             t.start()
             threads.append(t)
            
         for t in threads:
             t.join()
            
         print('result :', result)
            
         print('----- way_1 end -----\n')
            
            
     def way_2():
         print('----- way_2 start -----')
            
         Test().run_1()
            
         print('----- way_2 end -----\n')
            
            
     def way_3():
         print('----- way_3 start -----')
            
         threads = []
            
         lock = threading.Lock()
         count = 100000
         result = [0]
            
         for i in range(0, 2):
             t = threading.Thread(target=worker, args=(lock, count, result))
             t.start()
             threads.append(t)
            
         for t in threads:
             t.join()
            
         print('result :', result)
            
         print('----- way_3 end -----\n')
            
            
     def way_4():
         print('----- way_4 start -----')
            
         Test().run_2()
            
         print('----- way_4 end -----\n')
            
            
     if __name__ == '__main__':
         print('__main__ start\n')
            
         way_1()
         way_2()
         way_3()
         way_4()
            
         print('__main__ end')
    

• 실행 결과

  •  __main__ start
            
     ----- way_1 start -----
     threading.get_native_id() : 1212671
     threading.current_thread().name : Thread-1
     threading.get_ident() : 140377215727168
            
     threading.get_native_id() : 1212672
     threading.current_thread().name : Thread-2
     threading.get_ident() : 140377207334464
            
     result : [200000]
     ----- way_1 end -----
            
     ----- way_2 start -----
     arg1 : 1
     arg2 : 2
     arg1 : 1
     arg2 : 2
     self.result : 200000
     ----- way_2 end -----
            
     ----- way_3 start -----
     result : [200000]
     ----- way_3 end -----
            
     ----- way_4 start -----
             ~~~ dameon=False start ~~~
             ~~~ daemon=True start ~~~
     ----- way_4 end -----
            
     __main__ end
             ~~~ dameon=False end ~~~