diff --git a/python/examples/imdb/test_py_server.py b/python/examples/imdb/test_py_server.py
index f2d1e450940eb1ae17641c8c86fbf738eb7da34e..3d90161c88e53f3edde9557e69885950782f4459 100644
--- a/python/examples/imdb/test_py_server.py
+++ b/python/examples/imdb/test_py_server.py
@@ -18,9 +18,15 @@ from pyserver import Channel
 from pyserver import PyServer
 import numpy as np
 import python_service_channel_pb2
+import logging
 
+logging.basicConfig(
+    format='%(asctime)s %(levelname)-8s [%(filename)s:%(lineno)d] %(message)s',
+    datefmt='%Y-%m-%d %H:%M',
+    level=logging.INFO)
 
 # channel data: {name(str): data(bytes)}
+"""
 class ImdbOp(Op):
     def postprocess(self, output_data):
         data = python_service_channel_pb2.ChannelData()
@@ -28,36 +34,44 @@ class ImdbOp(Op):
         pred = np.array(output_data["prediction"][0][0], dtype='float')
         inst.data = np.ndarray.tobytes(pred)
         inst.name = "prediction"
-        inst.id = 0  #TODO
+        inst.id = 0 #TODO
         data.insts.append(inst)
         return data
+"""
 
 
 class CombineOp(Op):
     def preprocess(self, input_data):
+        data_id = None
         cnt = 0
         for input in input_data:
             data = input[0]  # batchsize=1
             cnt += np.frombuffer(data.insts[0].data, dtype='float')
+            if data_id is None:
+                data_id = data.id
+            if data_id != data.id:
+                raise Exception("id not match: {} vs {}".format(data_id,
+                                                                data.id))
         data = python_service_channel_pb2.ChannelData()
         inst = python_service_channel_pb2.Inst()
         inst.data = np.ndarray.tobytes(cnt)
         inst.name = "resp"
-        inst.id = 0  #TODO
         data.insts.append(inst)
+        data.id = data_id
         print(data)
         return data
 
 
 class UciOp(Op):
     def postprocess(self, output_data):
+        data_ids = self.get_data_ids()
         data = python_service_channel_pb2.ChannelData()
         inst = python_service_channel_pb2.Inst()
         pred = np.array(output_data["price"][0][0], dtype='float')
         inst.data = np.ndarray.tobytes(pred)
         inst.name = "prediction"
-        inst.id = 0  #TODO
         data.insts.append(inst)
+        data.id = data_ids[0]
         return data
 
 
@@ -121,5 +135,5 @@ pyserver.add_channel(combine_out_channel)
 pyserver.add_op(cnn_op)
 pyserver.add_op(bow_op)
 pyserver.add_op(combine_op)
-pyserver.prepare_server(port=8080, worker_num=1)
+pyserver.prepare_server(port=8080, worker_num=2)
 pyserver.run_server()
diff --git a/python/paddle_serving_server/pyserver.py b/python/paddle_serving_server/pyserver.py
index b64ac968ae027c60ed3fdc660ff62c8ec2d56fe3..4849f4e0fc7333fca486a2a16d5343131f5adf8f 100644
--- a/python/paddle_serving_server/pyserver.py
+++ b/python/paddle_serving_server/pyserver.py
@@ -24,6 +24,8 @@ import grpc
 import general_python_service_pb2
 import general_python_service_pb2_grpc
 import python_service_channel_pb2
+import logging
+import time
 
 
 class Channel(Queue.Queue):
@@ -39,10 +41,12 @@ class Channel(Queue.Queue):
         self._pushbatch = []
         self._frontbatch = None
         self._count = 0
+        self._order = 0
 
     def push(self, item):
         with self._pushlock:
             self._pushbatch.append(item)
+            self._order += 1
             if len(self._pushbatch) == self._batchsize:
                 self.put(self._pushbatch, timeout=self._timeout)
                 # self.put(self._pushbatch)
@@ -87,6 +91,7 @@ class Op(object):
         self._server_model = server_model
         self._server_port = server_port
         self._device = device
+        self._data_ids = []
 
     def set_client(self, client_config, server_name, fetch_names):
         self._client = Client()
@@ -113,12 +118,22 @@ class Op(object):
             raise TypeError('channels must be list type')
         self._outputs = channels
 
+    def get_data_ids(self):
+        return self._data_ids
+
+    def clear_data_ids(self):
+        self._data_ids = []
+
+    def append_id_to_data_ids(self, data_id):
+        self._data_ids.append(data_id)
+
     def preprocess(self, input_data):
         if len(input_data) != 1:
             raise Exception(
                 'this Op has multiple previous channels. Please override this method'
             )
         feed_batch = []
+        self.clear_data_ids()
         for data in input_data:
             if len(data.insts) != self._batch_size:
                 raise Exception('len(data_insts) != self._batch_size')
@@ -126,12 +141,13 @@ class Op(object):
             for inst in data.insts:
                 feed[inst.name] = np.frombuffer(inst.data, dtype=self._in_dtype)
             feed_batch.append(feed)
+            self.append_id_to_data_ids(data.id)
         return feed_batch
 
     def midprocess(self, data):
         # data = preprocess(input), which must be a dict
-        print('data: {}'.format(data))
-        print('fetch: {}'.format(self._fetch_names))
+        logging.debug('data: {}'.format(data))
+        logging.debug('fetch: {}'.format(self._fetch_names))
         fetch_map = self._client.predict(feed=data, fetch=self._fetch_names)
         return fetch_map
 
@@ -168,36 +184,80 @@ class GeneralPythonService(
         super(GeneralPythonService, self).__init__()
         self._in_channel = in_channel
         self._out_channel = out_channel
-        print('succ init')
-
-    def inference(self, request, context):
-        print('start inferce')
+        self._lock = threading.Lock()
+        self._globel_resp_dict = {}
+        self._id_counter = 0
+        self._recive_func = threading.Thread(
+            target=GeneralPythonService._recive_out_channel_func, args=(self, ))
+        self._recive_func.start()
+        logging.debug('succ init')
+
+    def _recive_out_channel_func(self):
+        while True:
+            data = self._out_channel.front()
+            data_id = None
+            for d in data:
+                if data_id is None:
+                    data_id = d.id
+                if data_id != d.id:
+                    raise Exception("id not match: {} vs {}".format(data_id,
+                                                                    d.id))
+            with self._lock:
+                self._globel_resp_dict[data_id] = data
+            #TODO wake up inference
+
+    def _get_next_id(self):
+        with self._lock:
+            self._id_counter += 1
+            return self._id_counter - 1
+
+    def _get_data_in_globel_resp_dict(self, data_id):
+        if data_id in self._globel_resp_dict:
+            with self._lock:
+                return self._globel_resp_dict.pop(data_id)
+        return None
+
+    def _pack_data_for_infer(self, request):
+        logging.debug('start inferce')
         data = python_service_channel_pb2.ChannelData()
-        print('gen data: {}'.format(data))
+        data_id = self._get_next_id()
+        data.id = data_id
         for idx, name in enumerate(request.feed_var_names):
-            print('name: {}'.format(request.feed_var_names[idx]))
-            print('data: {}'.format(request.feed_insts[idx]))
+            logging.debug('name: {}'.format(request.feed_var_names[idx]))
+            logging.debug('data: {}'.format(request.feed_insts[idx]))
             inst = python_service_channel_pb2.Inst()
             inst.data = request.feed_insts[idx]
             inst.name = name
-            inst.id = 0  #TODO
             data.insts.append(inst)
-        print('push data')
-        self._in_channel.push(data)
-        print('wait for infer')
-        data = self._out_channel.front()
+        return data, data_id
+
+    def _pack_data_for_resp(self, data):
         data = data[0]  #TODO batchsize = 1
-        print('get data')
+        logging.debug('get data')
         resp = general_python_service_pb2.Response()
-        print('gen resp')
-        print(data)
+        logging.debug('gen resp')
+        logging.debug(data)
         for inst in data.insts:
-            print('append data')
+            logging.debug('append data')
             resp.fetch_insts.append(inst.data)
-            print('append name')
+            logging.debug('append name')
             resp.fetch_var_names.append(inst.name)
         return resp
 
+    def inference(self, request, context):
+        data, data_id = self._pack_data_for_infer(request)
+        logging.debug('push data')
+        self._in_channel.push(data)
+        logging.debug('wait for infer')
+        resp_data = None
+        while True:
+            resp_data = self._get_data_in_globel_resp_dict(data_id)
+            if resp_data is not None:
+                break
+            time.sleep(0.05)  #TODO: wake up by _recive_out_channel_func
+        resp = self._pack_data_for_resp(resp_data)
+        return resp
+
 
 class PyServer(object):
     def __init__(self):
@@ -216,7 +276,7 @@ class PyServer(object):
         self._ops.append(op)
 
     def gen_desc(self):
-        print('here will generate desc for paas')
+        logging.info('here will generate desc for paas')
         pass
 
     def prepare_server(self, port, worker_num):
@@ -273,6 +333,6 @@ class PyServer(object):
         else:
             cmd = "python -m paddle_serving_server_gpu.serve --model {} --thread 4 --port {} &>/dev/null &".format(
                 model_path, port)
-        print(cmd)
+        logging.info(cmd)
         return
         os.system(cmd)
diff --git a/python/paddle_serving_server/python_service_channel.proto b/python/paddle_serving_server/python_service_channel.proto
index 2314368d7f50494f017890ff793460947f04e44f..dc97d3eb5bedf2d954e00840da458d39674de498 100644
--- a/python/paddle_serving_server/python_service_channel.proto
+++ b/python/paddle_serving_server/python_service_channel.proto
@@ -14,11 +14,13 @@
 
 syntax = "proto2";
 
-message ChannelData { repeated Inst insts = 1; }
+message ChannelData {
+  repeated Inst insts = 1;
+  required int32 id = 2;
+  optional string type = 3 [ default = "channel" ];
+}
 
 message Inst {
   required bytes data = 1;
   required string name = 2;
-  required int32 id = 3;
-  optional string type = 4 [ default = "channel" ];
 }