diff --git a/fluid/DeepASR/data_utils/async_data_reader.py b/fluid/DeepASR/data_utils/async_data_reader.py
index 03448fadccfbcfb67ab28cdf2071fc4b743ef6e5..ffb37f5cce81553aed0fbf6ae0c3b7fd018b45a4 100644
--- a/fluid/DeepASR/data_utils/async_data_reader.py
+++ b/fluid/DeepASR/data_utils/async_data_reader.py
@@ -22,7 +22,6 @@ from data_utils.util import CriticalException, ForceExitWrapper, EpochEndSignal
 
 class SampleInfo(object):
     """SampleInfo holds the necessary information to load a sample from disk.
-
     Args:
         feature_bin_path (str): File containing the feature data.
         feature_start (int): Start position of the sample's feature data.
@@ -55,7 +54,6 @@ class SampleInfoBucket(object):
     data, sample start position, sample byte number etc.) to access samples'
     feature data and the same with the label description file. SampleInfoBucket
     is the minimum unit to do shuffle.
-
     Args:
         feature_bin_paths (list|tuple): Files containing the binary feature
                                         data.
@@ -165,7 +163,6 @@ class SampleInfoBucket(object):
 class AsyncDataReader(object):
     """DataReader provides basic audio sample preprocessing pipeline including
     data loading and data augmentation.
-
     Args:
         feature_file_list (str): File containing paths of feature data file and
                                  corresponding description file.
@@ -209,8 +206,6 @@ class AsyncDataReader(object):
         self.generate_bucket_list(True)
         self._order_id = 0
         self._manager = Manager()
-        self._sample_buffer_size = sample_buffer_size
-        self._sample_info_buffer_size = sample_info_buffer_size
         self._batch_buffer_size = batch_buffer_size
         self._proc_num = proc_num
         if self._proc_num <= 2:
@@ -218,6 +213,10 @@ class AsyncDataReader(object):
         self._sample_proc_num = self._proc_num - 2
         self._verbose = verbose
         self._force_exit = ForceExitWrapper(self._manager.Value('b', False))
+        # buffer queue
+        self._sample_info_queue = self._manager.Queue(sample_info_buffer_size)
+        self._sample_queue = self._manager.Queue(sample_buffer_size)
+        self._batch_queue = self._manager.Queue(batch_buffer_size)
 
     def generate_bucket_list(self, is_shuffle):
         if self._block_info_list is None:
@@ -258,8 +257,6 @@ class AsyncDataReader(object):
             shared_ndarray.recycle(self._pool_manager.pool)
 
     def _start_async_processing(self):
-        sample_info_queue = self._manager.Queue(self._sample_info_buffer_size)
-        sample_queue = self._manager.Queue(self._sample_buffer_size)
         self._order_id = 0
 
         @suppress_complaints(verbose=self._verbose, notify=self._force_exit)
@@ -284,7 +281,9 @@ class AsyncDataReader(object):
                 sample_info_queue.put(EpochEndSignal())
 
         feeding_proc = DaemonProcessGroup(
-            proc_num=1, target=ordered_feeding_task, args=(sample_info_queue, ))
+            proc_num=1,
+            target=ordered_feeding_task,
+            args=(self._sample_info_queue, ))
         feeding_proc.start_all()
 
         @suppress_complaints(verbose=self._verbose, notify=self._force_exit)
@@ -361,15 +360,13 @@ class AsyncDataReader(object):
             sample_queue.put(EpochEndSignal())
 
         out_order = self._manager.list([0])
-        args = (sample_info_queue, sample_queue, out_order)
+        args = (self._sample_info_queue, self._sample_queue, out_order)
         sample_proc = DaemonProcessGroup(
             proc_num=self._sample_proc_num,
             target=ordered_processing_task,
             args=args)
         sample_proc.start_all()
 
-        return sample_queue
-
     def batch_iterator(self, batch_size, minimum_batch_size):
         @suppress_complaints(verbose=self._verbose, notify=self._force_exit)
         def batch_assembling_task(sample_queue, batch_queue, pool):
@@ -419,8 +416,7 @@ class AsyncDataReader(object):
 
             batch_queue.put(EpochEndSignal())
 
-        sample_queue = self._start_async_processing()
-        batch_queue = self._manager.Queue(self._batch_buffer_size)
+        self._start_async_processing()
 
         self._pool_manager = SharedMemoryPoolManager(self._batch_buffer_size *
                                                      3, self._manager)
@@ -428,12 +424,13 @@ class AsyncDataReader(object):
         assembling_proc = DaemonProcessGroup(
             proc_num=1,
             target=batch_assembling_task,
-            args=(sample_queue, batch_queue, self._pool_manager.pool))
+            args=(self._sample_queue, self._batch_queue,
+                  self._pool_manager.pool))
         assembling_proc.start_all()
 
         while self._force_exit == False:
             try:
-                batch_data = batch_queue.get_nowait()
+                batch_data = self._batch_queue.get_nowait()
             except Queue.Empty:
                 time.sleep(0.001)
             else: