diff --git a/data_utils/data.py b/data_utils/data.py
index 8391dacc1f6925b6929d390ce1717a1a2551481f..44af7ffaa999c618a7dcd4884f528ef60e59eefe 100644
--- a/data_utils/data.py
+++ b/data_utils/data.py
@@ -7,6 +7,7 @@ from __future__ import print_function
 
 import random
 import numpy as np
+import multiprocessing
 import paddle.v2 as paddle
 from data_utils import utils
 from data_utils.augmentor.augmentation import AugmentationPipeline
@@ -60,7 +61,7 @@ class DataGenerator(object):
                  window_ms=20.0,
                  max_freq=None,
                  specgram_type='linear',
-                 num_threads=12,
+                 num_threads=multiprocessing.cpu_count(),
                  random_seed=0):
         self._max_duration = max_duration
         self._min_duration = min_duration
diff --git a/infer.py b/infer.py
index 7fc8482966258be0dd9721cc9510a467ccb0d232..71518133a347c459bbcf2670fa5d1dc226a619c8 100644
--- a/infer.py
+++ b/infer.py
@@ -6,6 +6,7 @@ from __future__ import print_function
 import argparse
 import gzip
 import distutils.util
+import multiprocessing
 import paddle.v2 as paddle
 from data_utils.data import DataGenerator
 from model import deep_speech2
@@ -40,7 +41,7 @@ parser.add_argument(
     help="Use gpu or not. (default: %(default)s)")
 parser.add_argument(
     "--num_threads_data",
-    default=12,
+    default=multiprocessing.cpu_count(),
     type=int,
     help="Number of cpu threads for preprocessing data. (default: %(default)s)")
 parser.add_argument(
diff --git a/train.py b/train.py
index 2c3b8ce78c608801e4789998d1148adbf6460f5d..fc23ec72692f319b556a75004a7508990df5357e 100644
--- a/train.py
+++ b/train.py
@@ -9,6 +9,7 @@ import argparse
 import gzip
 import time
 import distutils.util
+import multiprocessing
 import paddle.v2 as paddle
 from model import deep_speech2
 from data_utils.data import DataGenerator
@@ -77,7 +78,7 @@ parser.add_argument(
     help="Trainer number. (default: %(default)s)")
 parser.add_argument(
     "--num_threads_data",
-    default=12,
+    default=multiprocessing.cpu_count(),
     type=int,
     help="Number of cpu threads for preprocessing data. (default: %(default)s)")
 parser.add_argument(