diff --git a/Dockerfile.android b/Dockerfile.android
index fa24f6f06c4e76444c83bcf13fe312afdcb6c348..c0fa58c384f9ebcae60477ffce49ea4ffa929db9 100644
--- a/Dockerfile.android
+++ b/Dockerfile.android
@@ -14,6 +14,17 @@ RUN apt-get update && \
     wget curl tar unzip gcc g++ locales clang-format-3.8 swig cmake && \
     apt-get clean -y
 
+# Install Go and glide
+RUN wget -O go.tgz https://storage.googleapis.com/golang/go1.8.1.linux-amd64.tar.gz && \
+    tar -C /usr/local -xzf go.tgz && \
+    mkdir /root/gopath && \
+    mkdir /root/gopath/bin && \
+    mkdir /root/gopath/src && \
+    rm go.tgz
+ENV GOROOT=/usr/local/go GOPATH=/root/gopath
+# should not be in the same line with GOROOT definition, otherwise docker build could not find GOROOT.
+ENV PATH=${PATH}:${GOROOT}/bin:${GOPATH}/bin
+
 # git credential to skip password typing
 RUN git config --global credential.helper store
 
diff --git a/cmake/cross_compiling/android.cmake b/cmake/cross_compiling/android.cmake
index dcfbc5d0129d7763daaf17c33d2b7791e87d3018..5e3e437a8da9624df35a5c754fe77be73f20361d 100644
--- a/cmake/cross_compiling/android.cmake
+++ b/cmake/cross_compiling/android.cmake
@@ -108,6 +108,7 @@ IF("${CMAKE_VERSION}" VERSION_LESS "3.7.0")
         ENDIF()
         IF(ANDROID_ABI STREQUAL "arm64-v8a")
             SET(ANDROID_TOOLCHAIN_NAME aarch64-linux-android)
+            SET(CMAKE_SYSTEM_PROCESSOR aarch64)
         ENDIF()
         SET(ANDROID_TOOLCHAIN_PREFIX "${ANDROID_TOOLCHAIN_ROOT}/bin/${ANDROID_TOOLCHAIN_NAME}-")
     ENDIF()
@@ -166,7 +167,7 @@ IF("${CMAKE_VERSION}" VERSION_LESS "3.7.0")
     ENDIF()
 
     IF(ANDROID_ABI STREQUAL "arm64-v8a")
-      LIST(APPEND ANDROID_COMPILER_FLAGS -march=armv8-a)
+        LIST(APPEND ANDROID_COMPILER_FLAGS -march=armv8-a)
     ENDIF()
 
     STRING(REPLACE ";" " " ANDROID_COMPILER_FLAGS "${ANDROID_COMPILER_FLAGS}")
@@ -193,6 +194,10 @@ ELSE()
         SET(CMAKE_ANDROID_STANDALONE_TOOLCHAIN ${ANDROID_STANDALONE_TOOLCHAIN})
     ENDIF()
     SET(CMAKE_ANDROID_ARCH_ABI ${ANDROID_ABI})
-    SET(CMAKE_ANDROID_ARM_MODE ${ANDROID_ARM_MODE})
-    SET(CMAKE_ANDROID_ARM_NEON ${ANDROID_ARM_NEON})
+    IF(ANDROID_ABI MATCHES "^armeabi(-v7a)?$")
+        SET(CMAKE_ANDROID_ARM_MODE ${ANDROID_ARM_MODE})
+        IF(ANDROID_ABI STREQUAL "armeabi-v7a")
+            SET(CMAKE_ANDROID_ARM_NEON ${ANDROID_ARM_NEON})
+        ENDIF()
+    ENDIF()
 ENDIF()
diff --git a/go/cmd/master/master.go b/go/cmd/master/master.go
index 54fa254863156455f66fa87de9077042a45f9735..9eaf8c04ae01fe7eebc92c51803bfcf977995ee3 100644
--- a/go/cmd/master/master.go
+++ b/go/cmd/master/master.go
@@ -11,6 +11,7 @@ import (
 
 	"github.com/namsral/flag"
 	log "github.com/sirupsen/logrus"
+	"github.com/topicai/candy"
 
 	"github.com/PaddlePaddle/Paddle/go/master"
 	"github.com/PaddlePaddle/Paddle/go/utils/networkhelper"
@@ -20,11 +21,18 @@ func main() {
 	port := flag.Int("port", 8080, "port of the master server.")
 	ttlSec := flag.Int("ttl", 60, "etcd lease TTL in seconds.")
 	endpoints := flag.String("endpoints", "http://127.0.0.1:2379", "comma separated etcd endpoints. If empty, fault tolerance will not be enabled.")
-	taskTimeoutDur := flag.Duration("task_timout_dur", 20*time.Minute, "task timout duration.")
-	taskTimeoutMax := flag.Int("task_timeout_max", 3, "max timtout count for each task before it being declared failed task.")
-	chunkPerTask := flag.Int("chunk_per_task", 10, "chunk per task.")
+	taskTimeoutDur := flag.Duration("task-timout-dur", 20*time.Minute, "task timout duration.")
+	taskTimeoutMax := flag.Int("task-timeout-max", 3, "max timtout count for each task before it being declared failed task.")
+	chunkPerTask := flag.Int("chunk-per-task", 10, "chunk per task.")
+	logLevel := flag.String("log-level", "info",
+		"log level, possible values: debug, info, warning, error, fatal, panic")
 	flag.Parse()
 
+	level, e := log.ParseLevel(*logLevel)
+	candy.Must(e)
+
+	log.SetLevel(level)
+
 	if *endpoints == "" {
 		log.Warningln("-endpoints not set, fault tolerance not be enabled.")
 	}
diff --git a/go/cmd/pserver/pserver.go b/go/cmd/pserver/pserver.go
index b331b8126cadc2c5df516fb241913415b2e3e73d..652d7ba315d72ff19931b82a4b0d1c30b2ff8f37 100644
--- a/go/cmd/pserver/pserver.go
+++ b/go/cmd/pserver/pserver.go
@@ -40,7 +40,7 @@ func main() {
 		idx = *index
 	} else {
 		e = pserver.NewEtcdClient(*etcdEndpoint, *numPservers, *etcdTimeout)
-		idx, err = e.Register()
+		idx, err = e.Register(*port)
 		candy.Must(err)
 
 		cp, err = pserver.NewCheckpointFromFile(*checkpointPath, idx, e)
diff --git a/go/master/client.go b/go/master/client.go
index a2ca3f3ef8ce300e3df09a302d74b56ee23c6d10..de883bf4b9a3de8d6d6e35e8e808dcf7ba54cb46 100644
--- a/go/master/client.go
+++ b/go/master/client.go
@@ -2,6 +2,7 @@ package master
 
 import (
 	"os"
+	"time"
 
 	"github.com/PaddlePaddle/Paddle/go/connection"
 	"github.com/PaddlePaddle/recordio"
@@ -36,9 +37,9 @@ func (c *Client) getRecords() {
 	for {
 		t, err := c.getTask()
 		if err != nil {
-			// TODO(helin): wait before move on with next
 			// getTask call.
-			log.Errorln(err)
+			log.Errorf("Get task failed, sleep 3 seconds and continue, %s", err)
+			time.Sleep(3 * time.Second)
 			continue
 		}
 
diff --git a/go/master/service.go b/go/master/service.go
index a6050ab99437244dade83f2943f6649453d47fff..9cef2270ce6a51425e40b9281f93f2f9c9981329 100644
--- a/go/master/service.go
+++ b/go/master/service.go
@@ -215,6 +215,7 @@ func readChunks(globPaths []string) ([]Chunk, error) {
 		}
 
 		count := index.NumChunks()
+		log.Infof("readChunks: file %s has %d chunks", path, count)
 		for i := 0; i < count; i++ {
 			chunk := Chunk{
 				Path:  path,
diff --git a/go/pserver/client/c/test/test_train.py b/go/pserver/client/c/test/test_train.py
index d6922672f4c1253e62cfe54965f6c2f3b5e6c7bf..e9264592b4f18fddf68b198d73bf907206e77a3f 100644
--- a/go/pserver/client/c/test/test_train.py
+++ b/go/pserver/client/c/test/test_train.py
@@ -1,5 +1,23 @@
 import paddle.v2 as paddle
 import paddle.v2.dataset.uci_housing as uci_housing
+import paddle.v2.master as master
+import os
+import cPickle as pickle
+
+etcd_ip = os.getenv("MASTER_IP", "127.0.0.1")
+etcd_endpoint = "http://" + etcd_ip + ":2379"
+
+
+def cloud_reader():
+    print "connecting to master, etcd endpoints: ", etcd_endpoint
+    master_client = master.client(etcd_endpoint, 5, 64)
+    master_client.set_dataset(
+        ["/pfs/dlnel/public/dataset/uci_housing/uci_housing-*-of-*"])
+    while 1:
+        r, e = master_client.next_record()
+        if not r:
+            break
+        yield pickle.loads(r)
 
 
 def main():
@@ -22,13 +40,13 @@ def main():
     # create optimizer of new remote updater to pserver
     optimizer = paddle.optimizer.Momentum(momentum=0)
 
-    #TODO(zhihong) : replace optimizer with new OptimizerConfig
-
+    print "etcd endoint: ", etcd_endpoint
     trainer = paddle.trainer.SGD(cost=cost,
                                  parameters=parameters,
                                  update_equation=optimizer,
                                  is_local=False,
-                                 pserver_spec="localhost:3000")
+                                 pserver_spec=etcd_endpoint,
+                                 use_etcd=True)
 
     # event_handler to print training and testing info
     def event_handler(event):
@@ -47,11 +65,11 @@ def main():
                 print "Test %d, %.2f" % (event.pass_id, result.cost)
 
     # training
+    # NOTE: use uci_housing.train() as reader for non-paddlecloud training
     trainer.train(
         reader=paddle.batch(
             paddle.reader.shuffle(
-                uci_housing.train(), buf_size=500),
-            batch_size=2),
+                cloud_reader, buf_size=500), batch_size=2),
         feeding={'x': 0,
                  'y': 1},
         event_handler=event_handler,
diff --git a/go/pserver/client/etcd_client.go b/go/pserver/client/etcd_client.go
index 1fd3479aa88ccbbe7c5067da1e9886b65352e847..8eb2a4f4511fc7139a55a2cd47ad73a82137b260 100644
--- a/go/pserver/client/etcd_client.go
+++ b/go/pserver/client/etcd_client.go
@@ -12,6 +12,7 @@ import (
 )
 
 const (
+	// DefaultEtcdTimeout is the default etcd timeout
 	DefaultEtcdTimeout time.Duration = 5 * time.Second
 )
 
@@ -66,12 +67,12 @@ func (p *EtcdClient) List() []Server {
 	for {
 		for i := 0; i < psDesired; i++ {
 			ctx, cancel := context.WithTimeout(context.Background(), p.timeout)
-			cancel()
 			psKey := pserver.PsPath + strconv.Itoa(i)
 			log.Debugf("checking %s", psKey)
 			resp, err := p.client.Get(ctx, psKey)
+			cancel()
 			if err != nil {
-				log.Infof("Get psKey= %s error, %v", psKey, err)
+				log.Infof("Get psKey=%s error, %v", psKey, err)
 				time.Sleep(p.timeout)
 				continue
 			}
diff --git a/go/pserver/etcd_client.go b/go/pserver/etcd_client.go
index 4a694b97f47b2ab85d1e109ef7545d104194b5cf..66af4fa0b483f1caea385df61e54d871072a0375 100644
--- a/go/pserver/etcd_client.go
+++ b/go/pserver/etcd_client.go
@@ -49,7 +49,7 @@ func NewEtcdClient(endpoints string, numPservers int, timeout time.Duration) *Et
 // Register registers the pserver on etcd
 //
 // Register returns the index of the current pserver.
-func (e *EtcdClient) Register() (int, error) {
+func (e *EtcdClient) Register(port int) (int, error) {
 
 	var err error
 	e.externalIP, err = networkhelper.GetExternalIP()
@@ -116,7 +116,7 @@ func (e *EtcdClient) Register() (int, error) {
 	for {
 		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
 		var err error
-		pserverIdx, err = e.registerPserverEtcd(ctx)
+		pserverIdx, err = e.registerPserverEtcd(ctx, port)
 		cancel()
 		if err != nil {
 			log.Warn(err)
@@ -140,7 +140,7 @@ func (e *EtcdClient) initDesiredPservers(ctx context.Context, numPservers int) (
 }
 
 // registerPserverEtcd registers pserver node on etcd using transaction.
-func (e *EtcdClient) registerPserverEtcd(ctx context.Context) (int, error) {
+func (e *EtcdClient) registerPserverEtcd(ctx context.Context, port int) (int, error) {
 	var idx int
 	_, err := concurrency.NewSTM(e.etcdClient, func(c concurrency.STM) error {
 		registered := false
@@ -156,8 +156,9 @@ func (e *EtcdClient) registerPserverEtcd(ctx context.Context) (int, error) {
 					log.Fatal(err)
 				}
 				// find the first id and write info
-				c.Put(psKey, e.externalIP, clientv3.WithLease(resp.ID))
-				log.Debugf("set pserver node %s with value %s", psKey, e.externalIP)
+				pserverAddr := e.externalIP + ":" + strconv.Itoa(port)
+				c.Put(psKey, pserverAddr, clientv3.WithLease(resp.ID))
+				log.Debugf("set pserver node %s with value %s", psKey, pserverAddr)
 				ch, kaerr := e.etcdClient.KeepAlive(context.TODO(), resp.ID)
 				if kaerr != nil {
 					log.Errorf("keepalive etcd node error: %v", kaerr)
diff --git a/paddle/api/PaddleAPI.h b/paddle/api/PaddleAPI.h
index 5fb3d1c73bc56e921f13aafd27c25224e259b3fe..0b9b83d42974151d49250bdf0e7c397f59bf6a62 100644
--- a/paddle/api/PaddleAPI.h
+++ b/paddle/api/PaddleAPI.h
@@ -843,7 +843,8 @@ public:
                                                bool useSparseUpdater);
   static ParameterUpdater* createNewRemoteUpdater(
       OptimizationConfig* config,
-      const std::string pserverSpec) throw(UnsupportError);
+      const std::string pserverSpec,
+      const bool useEtcd) throw(UnsupportError);
   ~ParameterUpdater();
 
   /**
diff --git a/paddle/api/ParameterUpdater.cpp b/paddle/api/ParameterUpdater.cpp
index 1aaefdfb8107a2eaa0432211fd7df4f5f12d537f..5934cb898b5f6adc74c237b1733a7459d8437a28 100644
--- a/paddle/api/ParameterUpdater.cpp
+++ b/paddle/api/ParameterUpdater.cpp
@@ -33,11 +33,12 @@ ParameterUpdater *ParameterUpdater::createLocalUpdater(
 
 ParameterUpdater *ParameterUpdater::createNewRemoteUpdater(
     OptimizationConfig *config,
-    const std::string pserverSpec) throw(UnsupportError) {
+    const std::string pserverSpec,
+    const bool useEtcd) throw(UnsupportError) {
 #ifndef PADDLE_WITHOUT_GOLANG
   auto updater = new ParameterUpdater();
   updater->m->updater.reset(new paddle::NewRemoteParameterUpdater(
-      config->m->getConfig(), pserverSpec));
+      config->m->getConfig(), pserverSpec, useEtcd));
   return updater;
 #else
   throw UnsupportError();
diff --git a/paddle/framework/CMakeLists.txt b/paddle/framework/CMakeLists.txt
index 31b138423526f48de7c11d45990cabfa1b559b67..eb3416462324edf6f6e76e32d7400d1fd774b9bd 100644
--- a/paddle/framework/CMakeLists.txt
+++ b/paddle/framework/CMakeLists.txt
@@ -1,22 +1,25 @@
 # ddim lib
+cc_library(enforce SRCS enforce.cc DEPS glog)
+cc_test(enforce_test SRCS enforce_test.cc DEPS enforce)
 cc_library(ddim SRCS ddim.cc DEPS eigen3)
 cc_test(ddim_test SRCS ddim_test.cc DEPS ddim)
 nv_test(dim_test SRCS dim_test.cu DEPS ddim)
-cc_test(tensor_test SRCS tensor_test.cc DEPS ddim)
+cc_library(tensor SRCS tensor.cc DEPS ddim place enforce paddle_memory)
+cc_test(tensor_test SRCS tensor_test.cc DEPS tensor)
 cc_test(variable_test SRCS variable_test.cc)
 cc_test(scope_test SRCS scope_test.cc)
-cc_test(enforce_test SRCS enforce_test.cc)
 proto_library(attr_type SRCS attr_type.proto)
 proto_library(op_proto SRCS op_proto.proto DEPS attr_type)
 cc_test(op_proto_test SRCS op_proto_test.cc DEPS op_proto protobuf)
 proto_library(op_desc SRCS op_desc.proto DEPS attr_type)
 cc_test(op_desc_test SRCS op_desc_test.cc DEPS op_desc protobuf)
 
-cc_library(operator SRCS operator.cc DEPS op_desc device_context)
+cc_library(operator SRCS operator.cc DEPS op_desc device_context tensor)
 cc_test(operator_test SRCS operator_test.cc DEPS operator op_registry)
 
-cc_library(op_registry SRCS op_registry.cc DEPS op_proto op_desc)
+cc_library(op_registry SRCS op_registry.cc DEPS op_proto op_desc enforce)
 cc_test(op_registry_test SRCS op_registry_test.cc DEPS op_registry operator)
+
 py_proto_compile(framework_py_proto SRCS attr_type.proto op_proto.proto op_desc.proto)
 # Generate an empty __init__.py to make framework_py_proto as a valid python module.
 add_custom_target(framework_py_proto_init ALL COMMAND ${CMAKE_COMMAND} -E touch __init__.py)
diff --git a/paddle/framework/ddim.cc b/paddle/framework/ddim.cc
index 87a3618e095c544b422746ed3f497b21f3824fbd..73f5499ad15752237a73ca27e0cd0fe2c5e86b4e 100644
--- a/paddle/framework/ddim.cc
+++ b/paddle/framework/ddim.cc
@@ -13,6 +13,7 @@ See the License for the specific language governing permissions and
 limitations under the License. */
 
 #include "paddle/framework/ddim.h"
+#include "paddle/framework/enforce.h"
 
 namespace paddle {
 namespace framework {
@@ -192,13 +193,56 @@ std::vector<int> vectorize(const DDim& ddim) {
   return result;
 }
 
+struct ProductVisitor : public boost::static_visitor<ssize_t> {
+  template <int D>
+  ssize_t operator()(const Dim<D>& dim) {
+    return product(dim);
+  }
+};
+
 ssize_t product(const DDim& ddim) {
-  ssize_t result = 1;
-  std::vector<int> v = vectorize(ddim);
-  for (auto i : v) {
-    result *= i;
+  ProductVisitor visitor;
+  return boost::apply_visitor(visitor, ddim);
+}
+
+struct SliceVectorizeVisitor : public boost::static_visitor<> {
+  std::vector<int>& vector;
+  int begin;
+  int end;
+
+  SliceVectorizeVisitor(std::vector<int>& v, int b, int e)
+      : vector(v), begin(b), end(e) {
+    PADDLE_ENFORCE(begin < end,
+                   "Begin index must be less than end index in ddim slice.");
+    PADDLE_ENFORCE(begin >= 0,
+                   "Begin index can't be less than zero in ddim slice.");
   }
-  return result;
+
+  template <int S>
+  void operator()(const Dim<S>& dim) {
+    if (begin == 0) {
+      vector.push_back(dim.head);
+    } else {
+      --begin;
+    }
+    --end;
+    if (end > 0) {
+      this->operator()(dim.tail);
+    }
+  }
+
+  void operator()(const Dim<1>& dim) {
+    PADDLE_ENFORCE(end == 1, "End index in ddim slice is out of bound.");
+    vector.push_back(dim.head);
+  }
+};
+
+DDim slice_ddim(const DDim& dim, int begin, int end) {
+  std::vector<int> vec;
+  vec.reserve(end - begin);
+  SliceVectorizeVisitor visitor(vec, begin, end);
+  boost::apply_visitor(visitor, dim);
+  return make_ddim(vec);
 }
 
 /// \cond HIDDEN
diff --git a/paddle/framework/ddim.h b/paddle/framework/ddim.h
index bd51b4fada773c986b92a61ec754fcf141b90e16..68cffcc4cbf1a2c515a4c0ded6e3864341eada82 100644
--- a/paddle/framework/ddim.h
+++ b/paddle/framework/ddim.h
@@ -96,6 +96,15 @@ std::vector<int> vectorize(const DDim& ddim);
 
 ssize_t product(const DDim& ddim);
 
+/**
+ * \brief Slice a ddim
+ *
+ * Slice dim with [begin, end).
+ * e.g.  DDim d = make_ddim({1,2,3,4,5});
+ *       slice_ddim(d, 1, 3); ====> {2,3}
+ */
+DDim slice_ddim(const DDim& dim, int begin, int end);
+
 /**
  * \brief What is the length of this dimension?
  *
diff --git a/paddle/framework/ddim_test.cc b/paddle/framework/ddim_test.cc
index 36eef02370e0196c2af2c05f49176b70ce69235a..6a099f2aeb4aa117bca8695aa326fbd1272a43d6 100644
--- a/paddle/framework/ddim_test.cc
+++ b/paddle/framework/ddim_test.cc
@@ -52,6 +52,26 @@ TEST(DDim, Equality) {
 
   // product of a DDim
   EXPECT_EQ(paddle::framework::product(vddim), 45);
+  EXPECT_EQ(
+      paddle::framework::product(paddle::framework::make_ddim({3, 2, 5, 3})),
+      90);
+
+  // slice a DDim
+  paddle::framework::DDim ddim2 =
+      paddle::framework::make_ddim({1, 2, 3, 4, 5, 6});
+  paddle::framework::DDim ss = paddle::framework::slice_ddim(ddim2, 2, 5);
+  EXPECT_EQ(arity(ss), 3);
+  EXPECT_EQ(ss[0], 3);
+  EXPECT_EQ(ss[1], 4);
+  EXPECT_EQ(ss[2], 5);
+  paddle::framework::DDim ss2 = paddle::framework::slice_ddim(ddim2, 0, 6);
+  EXPECT_EQ(arity(ss2), 6);
+  EXPECT_EQ(ss2[0], 1);
+  EXPECT_EQ(ss2[1], 2);
+  EXPECT_EQ(ss2[2], 3);
+  EXPECT_EQ(ss2[3], 4);
+  EXPECT_EQ(ss2[4], 5);
+  EXPECT_EQ(ss2[5], 6);
 }
 
 TEST(DDim, Print) {
diff --git a/paddle/framework/dim_test.cu b/paddle/framework/dim_test.cu
index 05217415196f3ec3ce9b5de7cb2f82c9de960ba7..3898d0a447aa502813b3cb5e86c29eebb814ff84 100644
--- a/paddle/framework/dim_test.cu
+++ b/paddle/framework/dim_test.cu
@@ -1,100 +1,101 @@
 #include <thrust/device_vector.h>
 #include <sstream>
 
-#include "paddle/framework/dim.h"
 #include "gtest/gtest.h"
+#include "paddle/framework/dim.h"
 
 __global__ void test(paddle::framework::Dim<2>* o) {
-    o[0] = paddle::framework::make_dim(5, 6);
+  o[0] = paddle::framework::make_dim(5, 6);
 }
 
 __global__ void dyn_idx_gpu(int* o) {
-    auto d = paddle::framework::make_dim(5, 6);
-    o[0] = d[1];
+  auto d = paddle::framework::make_dim(5, 6);
+  o[0] = d[1];
 }
 
 TEST(Dim, Equality) {
-    // construct a Dim on the CPU
-    auto a = paddle::framework::make_dim(3, 4);
-    EXPECT_EQ(paddle::framework::get<0>(a), 3);
-    EXPECT_EQ(paddle::framework::get<1>(a), 4);
-
-    // construct a Dim on the GPU
-    thrust::device_vector<paddle::framework::Dim<2>> t(2);
-    test<<<1,1>>>(thrust::raw_pointer_cast(t.data()));
-    a = t[0];
-    EXPECT_EQ(paddle::framework::get<0>(a), 5);
-    EXPECT_EQ(paddle::framework::get<1>(a), 6);
-
-    // linearization
-    auto b = paddle::framework::make_dim(7, 8);
-    EXPECT_EQ(paddle::framework::linearize(a, b), 83);
-
-    // product
-    EXPECT_EQ(paddle::framework::product(a), 30);
-
-    // mutate a Dim
-    paddle::framework::get<1>(b) = 10;
-    EXPECT_EQ(paddle::framework::get<0>(b), 7);
-    EXPECT_EQ(paddle::framework::get<1>(b), 10);
-
-    // dynamic access
-    paddle::framework::get(b, 0) = 8;
-    b[1] = 11;
-    EXPECT_EQ(paddle::framework::get<0>(b), 8);
-    EXPECT_EQ(paddle::framework::get<1>(b), 11);
-    EXPECT_EQ(paddle::framework::get(b, 0), 8);
-    EXPECT_EQ(b[1], 11);
-
-    // dynamic access on GPU
-    thrust::device_vector<int> r(1);
-    dyn_idx_gpu<<<1,1>>>(thrust::raw_pointer_cast(r.data()));
-    int res = r[0];
-    EXPECT_EQ(res, 6);
-
-    // ex_prefix_mul
-    paddle::framework::Dim<3> c = paddle::framework::ex_prefix_mul(paddle::framework::Dim<3>(3, 4, 5));
-    EXPECT_EQ(paddle::framework::get<0>(c), 1);
-    EXPECT_EQ(paddle::framework::get<1>(c), 3);
-    EXPECT_EQ(paddle::framework::get<2>(c), 12);
-
-    // generate from an index
-    auto size = paddle::framework::make_dim(4, 5, 2);
-    c = paddle::framework::Dim<3>(14, size);
-    EXPECT_EQ(paddle::framework::get<0>(c), 2);
-    EXPECT_EQ(paddle::framework::get<1>(c), 3);
-    EXPECT_EQ(paddle::framework::get<2>(c), 0);
-    c = paddle::framework::Dim<3>(25, size);
-    EXPECT_EQ(paddle::framework::get<0>(c), 1);
-    EXPECT_EQ(paddle::framework::get<1>(c), 1);
-    EXPECT_EQ(paddle::framework::get<2>(c), 1);
+  // construct a Dim on the CPU
+  auto a = paddle::framework::make_dim(3, 4);
+  EXPECT_EQ(paddle::framework::get<0>(a), 3);
+  EXPECT_EQ(paddle::framework::get<1>(a), 4);
+
+  // construct a Dim on the GPU
+  thrust::device_vector<paddle::framework::Dim<2>> t(2);
+  test<<<1, 1>>>(thrust::raw_pointer_cast(t.data()));
+  a = t[0];
+  EXPECT_EQ(paddle::framework::get<0>(a), 5);
+  EXPECT_EQ(paddle::framework::get<1>(a), 6);
+
+  // linearization
+  auto b = paddle::framework::make_dim(7, 8);
+  EXPECT_EQ(paddle::framework::linearize(a, b), 83);
+
+  // product
+  EXPECT_EQ(paddle::framework::product(a), 30);
+
+  // mutate a Dim
+  paddle::framework::get<1>(b) = 10;
+  EXPECT_EQ(paddle::framework::get<0>(b), 7);
+  EXPECT_EQ(paddle::framework::get<1>(b), 10);
+
+  // dynamic access
+  paddle::framework::get(b, 0) = 8;
+  b[1] = 11;
+  EXPECT_EQ(paddle::framework::get<0>(b), 8);
+  EXPECT_EQ(paddle::framework::get<1>(b), 11);
+  EXPECT_EQ(paddle::framework::get(b, 0), 8);
+  EXPECT_EQ(b[1], 11);
+
+  // dynamic access on GPU
+  thrust::device_vector<int> r(1);
+  dyn_idx_gpu<<<1, 1>>>(thrust::raw_pointer_cast(r.data()));
+  int res = r[0];
+  EXPECT_EQ(res, 6);
+
+  // ex_prefix_mul
+  paddle::framework::Dim<3> c =
+      paddle::framework::ex_prefix_mul(paddle::framework::Dim<3>(3, 4, 5));
+  EXPECT_EQ(paddle::framework::get<0>(c), 1);
+  EXPECT_EQ(paddle::framework::get<1>(c), 3);
+  EXPECT_EQ(paddle::framework::get<2>(c), 12);
+
+  // generate from an index
+  auto size = paddle::framework::make_dim(4, 5, 2);
+  c = paddle::framework::Dim<3>(14, size);
+  EXPECT_EQ(paddle::framework::get<0>(c), 2);
+  EXPECT_EQ(paddle::framework::get<1>(c), 3);
+  EXPECT_EQ(paddle::framework::get<2>(c), 0);
+  c = paddle::framework::Dim<3>(25, size);
+  EXPECT_EQ(paddle::framework::get<0>(c), 1);
+  EXPECT_EQ(paddle::framework::get<1>(c), 1);
+  EXPECT_EQ(paddle::framework::get<2>(c), 1);
 }
 
 TEST(Dim, Bool) {
-    auto a = paddle::framework::make_dim(3, 4);
-    auto b = paddle::framework::make_dim(5, 6);
-    auto c = paddle::framework::make_dim(3, 4);
-
-    // in_bounds check
-    EXPECT_TRUE(paddle::framework::contained(a, b));
-    EXPECT_FALSE(paddle::framework::contained(b, a));
-
-    // comparison
-    EXPECT_TRUE(a == a);
-    EXPECT_FALSE(a == b);
-    EXPECT_TRUE(a == c);
+  auto a = paddle::framework::make_dim(3, 4);
+  auto b = paddle::framework::make_dim(5, 6);
+  auto c = paddle::framework::make_dim(3, 4);
+
+  // in_bounds check
+  EXPECT_TRUE(paddle::framework::contained(a, b));
+  EXPECT_FALSE(paddle::framework::contained(b, a));
+
+  // comparison
+  EXPECT_TRUE(a == a);
+  EXPECT_FALSE(a == b);
+  EXPECT_TRUE(a == c);
 }
 
 TEST(Dim, Print) {
-    {
-        std::stringstream ss;
-        auto a = paddle::framework::make_dim(2, 3);
-        ss << a;
-        EXPECT_EQ(ss.str(), "2, 3");
-    }
-    {
-        std::stringstream ss;
-        ss << paddle::framework::make_dim(8);
-        EXPECT_EQ(ss.str(), "8");
-    }
+  {
+    std::stringstream ss;
+    auto a = paddle::framework::make_dim(2, 3);
+    ss << a;
+    EXPECT_EQ(ss.str(), "2, 3");
+  }
+  {
+    std::stringstream ss;
+    ss << paddle::framework::make_dim(8);
+    EXPECT_EQ(ss.str(), "8");
+  }
 }
diff --git a/paddle/framework/enforce.cc b/paddle/framework/enforce.cc
new file mode 100644
index 0000000000000000000000000000000000000000..644930ff989bb8935f37642c117084f580379bd7
--- /dev/null
+++ b/paddle/framework/enforce.cc
@@ -0,0 +1,15 @@
+/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License. */
+
+#include "paddle/framework/enforce.h"
diff --git a/paddle/framework/enforce.h b/paddle/framework/enforce.h
index 56cb7f95647e81efef58b156002d0d378ee22820..ffce8148e9516a5720757c87685ff6bd2937977c 100644
--- a/paddle/framework/enforce.h
+++ b/paddle/framework/enforce.h
@@ -10,6 +10,7 @@ See the License for the specific language governing permissions and
 limitations under the License. */
 
 #pragma once
+#include <glog/logging.h>
 #include <paddle/string/printf.h>
 #include <exception>
 #include <sstream>
@@ -58,12 +59,17 @@ class EnforceNotMet : public std::exception {
 /**
  * @brief Enforce a condition, otherwise throw an EnforceNotMet
  */
+#ifdef NDEBUG
 #define PADDLE_ENFORCE(condition, ...) \
   do {                                 \
     if (UNLIKELY(!(condition))) {      \
       PADDLE_THROW(__VA_ARGS__);       \
     }                                  \
   } while (0)
+#else
+#define PADDLE_ENFORCE(condition, ...) \
+  CHECK(condition) << ::paddle::string::Sprintf(__VA_ARGS__);
+#endif
 
 }  // namespace framework
 }  // namespace paddle
diff --git a/paddle/framework/op_registry.h b/paddle/framework/op_registry.h
index 24f56b281282881fb12fc8f2d477da310df5db6f..41bdb65f8e9bbbf63ec6e62e8c2243cc3d6f21de 100644
--- a/paddle/framework/op_registry.h
+++ b/paddle/framework/op_registry.h
@@ -61,7 +61,14 @@ class OpProtoAndCheckerMaker {
   OpProtoAndCheckerMaker(OpProto* proto, OpAttrChecker* op_checker)
       : proto_(proto), op_checker_(op_checker) {}
 
-  ~OpProtoAndCheckerMaker() { CheckNoDuplicatedAttrs(); }
+  ~OpProtoAndCheckerMaker() {
+    PADDLE_ENFORCE(validated_, "should call Validate after build");
+  }
+
+  void Validate() {
+    validated_ = true;
+    CheckNoDuplicatedInOutAttrs();
+  }
 
  protected:
   void AddInput(const std::string& name, const std::string& comment,
@@ -163,19 +170,26 @@ Add a mark to which output is temporary is helpful for future optimization.
     }
   }
 
-  void CheckNoDuplicatedAttrs() {
+  void CheckNoDuplicatedInOutAttrs() {
     std::unordered_set<std::string> names;
-    size_t cnt = 0;
+    auto checker = [&](const std::string& name) {
+      PADDLE_ENFORCE(!names.count(name), "[%s] is duplicated", name);
+      names.insert(name);
+    };
     for (auto& attr : proto_->attrs()) {
-      names.insert(attr.name());
-      ++cnt;
+      checker(attr.name());
+    }
+    for (auto& input : proto_->inputs()) {
+      checker(input.name());
+    }
+    for (auto& output : proto_->outputs()) {
+      checker(output.name());
     }
-    PADDLE_ENFORCE(names.size() == cnt,
-                   "Cannot register two attribute in same name!");
   }
 
   OpProto* proto_;
   OpAttrChecker* op_checker_;
+  bool validated_{false};
   bool has_multiple_input_{false};
   bool has_multiple_output_{false};
   bool has_temporary_output_{false};
@@ -190,7 +204,8 @@ class OpRegistry {
     creators()[op_type] = [] { return new OpType; };
     OpProto& op_proto = protos()[op_type];
     OpAttrChecker& op_checker = op_checkers()[op_type];
-    ProtoMakerType(&op_proto, &op_checker);
+    auto maker = ProtoMakerType(&op_proto, &op_checker);
+    maker.Validate();
     *op_proto.mutable_type() = op_type;
     PADDLE_ENFORCE(
         op_proto.IsInitialized(),
diff --git a/paddle/framework/op_registry_test.cc b/paddle/framework/op_registry_test.cc
index 4791d4aaab4cfe19d1cca7741ce259f8f7aeb18a..d3a51a361aa56b26b87d79057f6700bd87264ca4 100644
--- a/paddle/framework/op_registry_test.cc
+++ b/paddle/framework/op_registry_test.cc
@@ -1,6 +1,8 @@
 #include "paddle/framework/op_registry.h"
 #include <gtest/gtest.h>
 
+namespace pd = paddle::framework;
+
 namespace paddle {
 namespace framework {
 class CosineOp : public OperatorBase {
@@ -28,8 +30,6 @@ class MyTestOp : public OperatorBase {
   void InferShape(const ScopePtr& scope) const override {}
   void Run(const ScopePtr& scope,
            const platform::DeviceContext& dev_ctx) const override {}
-
- public:
 };
 
 class MyTestOpProtoAndCheckerMaker : public OpProtoAndCheckerMaker {
@@ -182,3 +182,35 @@ TEST(OpRegistry, CustomChecker) {
   int test_attr = op->GetAttr<int>("test_attr");
   ASSERT_EQ(test_attr, 4);
 }
+
+class TestAttrProtoMaker : public pd::OpProtoAndCheckerMaker {
+ public:
+  TestAttrProtoMaker(pd::OpProto* proto, pd::OpAttrChecker* op_checker)
+      : OpProtoAndCheckerMaker(proto, op_checker) {
+    AddAttr<float>("scale", "scale of test op");
+    AddAttr<float>("scale", "scale of test op");
+  }
+};
+
+TEST(ProtoMaker, DuplicatedAttr) {
+  pd::OpProto op_proto;
+  pd::OpAttrChecker op_checker;
+  auto proto_maker = TestAttrProtoMaker(&op_proto, &op_checker);
+  ASSERT_THROW(proto_maker.Validate(), paddle::framework::EnforceNotMet);
+}
+
+class TestInOutProtoMaker : public pd::OpProtoAndCheckerMaker {
+ public:
+  TestInOutProtoMaker(pd::OpProto* proto, pd::OpAttrChecker* op_checker)
+      : OpProtoAndCheckerMaker(proto, op_checker) {
+    AddInput("input", "input of test op");
+    AddInput("input", "input of test op");
+  }
+};
+
+TEST(ProtoMaker, DuplicatedInOut) {
+  pd::OpProto op_proto;
+  pd::OpAttrChecker op_checker;
+  auto proto_maker = TestInOutProtoMaker(&op_proto, &op_checker);
+  ASSERT_THROW(proto_maker.Validate(), paddle::framework::EnforceNotMet);
+}
diff --git a/paddle/framework/tensor.cc b/paddle/framework/tensor.cc
new file mode 100644
index 0000000000000000000000000000000000000000..964f15ab66bca7da75824e192e61600c29e572c0
--- /dev/null
+++ b/paddle/framework/tensor.cc
@@ -0,0 +1,19 @@
+/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserve.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License. */
+
+#include <paddle/framework/tensor.h>
+
+namespace paddle {
+namespace framework {}
+}  // namespace paddle
diff --git a/paddle/operators/CMakeLists.txt b/paddle/operators/CMakeLists.txt
index 50ecc6f85ca51f57da069ae445918bcf58a4a146..441b9e30c4268cce899ac873b2657c34603e0035 100644
--- a/paddle/operators/CMakeLists.txt
+++ b/paddle/operators/CMakeLists.txt
@@ -1,6 +1,44 @@
-if(WITH_GPU)
-    nv_library(add_op SRCS add_op.cc add_op.cu DEPS operator op_registry ddim glog paddle_memory)
-else()
-    cc_library(add_op SRCS add_op.cc DEPS operator op_registry ddim glog paddle_memory)
-endif()
+function(op_library TARGET)
+    # op_library is a function to create op library. The interface is same as
+    # cc_library. But it handle split GPU/CPU code and link some common library
+    # for ops.
+    set(cc_srcs)
+    set(cu_srcs)
+    set(op_common_deps operator op_registry)
+    set(options "")
+    set(oneValueArgs "")
+    set(multiValueArgs SRCS DEPS)
+    cmake_parse_arguments(op_library "${options}" "${oneValueArgs}"
+            "${multiValueArgs}" ${ARGN})
+
+    foreach(src ${op_library_SRCS})
+        if (${src} MATCHES ".*\\.cu$")
+            list(APPEND cu_srcs ${src})
+        elseif(${src} MATCHES ".*\\.cc$")
+            list(APPEND cc_srcs ${src})
+        else()
+            message(FATAL_ERROR "${TARGET} Source file ${src} should only be .cc or .cu")
+        endif()
+    endforeach()
+
+    list(LENGTH cc_srcs cc_srcs_len)
+    if (${cc_srcs_len} EQUAL 0)
+        message(FATAL_ERROR "The op library ${TARGET} should contains at least one .cc file")
+    endif()
+
+    list(LENGTH cu_srcs cu_srcs_len)
+    if (${cu_srcs_len} EQUAL 0)
+        message(WARNING "The op library ${TARGET} not support GPU!")
+    endif()
+
+    if (WITH_GPU)
+        nv_library(${TARGET} SRCS ${cc_srcs} ${cu_srcs} DEPS ${op_library_DEPS}
+                ${op_common_deps})
+    else()
+        cc_library(${TARGET} SRCS ${cc_srcs} DEPS ${op_library_DEPS}
+                ${op_common_deps})
+    endif()
+endfunction()
+
+op_library(add_op SRCS add_op.cc add_op.cu)
 cc_test(add_op_test SRCS add_op_test.cc DEPS add_op)
diff --git a/paddle/scripts/docker/build.sh b/paddle/scripts/docker/build.sh
index ab60f1a38dd4cd1d9799c0019dccae5f1c7d4310..3860facb099950a5287d3f6b89c3de38f588f568 100644
--- a/paddle/scripts/docker/build.sh
+++ b/paddle/scripts/docker/build.sh
@@ -155,7 +155,8 @@ RUN apt-get update &&\
     paddle version
 ${DOCKERFILE_CUDNN_DSO}
 ${DOCKERFILE_GPU_ENV}
-
+ADD go/cmd/pserver/pserver /usr/bin/
+ADD go/cmd/master/master /usr/bin/
 # default command shows the paddle version and exit
 CMD ["paddle", "version"]
 EOF
diff --git a/paddle/scripts/docker/build_android.sh b/paddle/scripts/docker/build_android.sh
index bfa10c91553563bddac8c1b41bf21490fb89d3cf..56d290be4ab04a9f6974023159aa8571d27f8dd5 100644
--- a/paddle/scripts/docker/build_android.sh
+++ b/paddle/scripts/docker/build_android.sh
@@ -2,9 +2,9 @@
 
 set -xe
 
-mkdir -p /paddle/build
-cd /paddle/build
-rm -f /paddle/install 2>/dev/null || true
+mkdir -p /paddle/build_android
+cd /paddle/build_android
+rm -rf /paddle/install 2>/dev/null || true
 cmake -DCMAKE_SYSTEM_NAME=Android \
       -DANDROID_STANDALONE_TOOLCHAIN=$ANDROID_STANDALONE_TOOLCHAIN \
       -DANDROID_ABI=armeabi-v7a \
@@ -21,6 +21,3 @@ cmake -DCMAKE_SYSTEM_NAME=Android \
       ..
 make -j `nproc`
 make install
-
-export PATH=/paddle/install/bin:/paddle/install/opt/paddle/bin:$PATH
-paddle version
diff --git a/paddle/trainer/NewRemoteParameterUpdater.cpp b/paddle/trainer/NewRemoteParameterUpdater.cpp
index b359d9da2167bf459504e15c3140b3d956f417f3..a830ceba5772846cd9255a3eeb26e8d6a17dcfbc 100644
--- a/paddle/trainer/NewRemoteParameterUpdater.cpp
+++ b/paddle/trainer/NewRemoteParameterUpdater.cpp
@@ -28,6 +28,17 @@ NewRemoteParameterUpdater::NewRemoteParameterUpdater(
       newGradients_(nullptr),
       pserverSpec_(pserverSpec) {}
 
+NewRemoteParameterUpdater::NewRemoteParameterUpdater(
+    const OptimizationConfig &config,
+    const std::string pserverSpec,
+    const bool useEtcd)
+    : trainerConfig_(config),
+      parameterClient_(-1),
+      newParameters_(nullptr),
+      newGradients_(nullptr),
+      pserverSpec_(pserverSpec),
+      useEtcd_(useEtcd) {}
+
 void NewRemoteParameterUpdater::init(
     const std::vector<ParameterPtr> &parameters) {
   ParameterUpdater::init(parameters);
@@ -38,8 +49,13 @@ void NewRemoteParameterUpdater::init(
   }
 
   // create parameter server client.
-  parameterClient_ = paddle_new_pserver_client((char *)pserverSpec_.c_str(),
-                                               FLAGS_trainer_id == 0);
+  if (useEtcd_) {
+    parameterClient_ = paddle_new_etcd_pserver_client(
+        (char *)pserverSpec_.c_str(), FLAGS_trainer_id == 0);
+  } else {
+    parameterClient_ = paddle_new_pserver_client((char *)pserverSpec_.c_str(),
+                                                 FLAGS_trainer_id == 0);
+  }
 
   // init new parameter and gradient.
   newParameters_ = initNewParameter(PARAMETER_VALUE);
diff --git a/paddle/trainer/NewRemoteParameterUpdater.h b/paddle/trainer/NewRemoteParameterUpdater.h
index dfed00bc216b1d41bb7520619b76702f9fe650f2..6223ba427c9b94494c2bee8f0847442f1b0574c9 100644
--- a/paddle/trainer/NewRemoteParameterUpdater.h
+++ b/paddle/trainer/NewRemoteParameterUpdater.h
@@ -32,6 +32,9 @@ class NewRemoteParameterUpdater : public ParameterUpdater {
 public:
   NewRemoteParameterUpdater(const OptimizationConfig& config,
                             const std::string pserverSpec);
+  NewRemoteParameterUpdater(const OptimizationConfig& config,
+                            const std::string pserverSpec,
+                            const bool useEtcd);
   ~NewRemoteParameterUpdater() {
     releaseNewParameter(newParameters_);
     releaseNewParameter(newGradients_);
@@ -111,6 +114,8 @@ protected:
   paddle_parameter** newGradients_;
   /// the specification of parameter server "host1:port,host1:port"
   std::string pserverSpec_;
+  /// true if pserverSpec_ is etcd endpoint, else pserverSpec_ is pserver addr
+  bool useEtcd_;
 };
 
 }  // namespace paddle
diff --git a/python/paddle/v2/dataset/common.py b/python/paddle/v2/dataset/common.py
index 4a2eb59c340f5d0d3818170e56d730330e0bab29..645f3cc0dce70752c20569523e4bab440861f6a1 100644
--- a/python/paddle/v2/dataset/common.py
+++ b/python/paddle/v2/dataset/common.py
@@ -22,6 +22,8 @@ import importlib
 import paddle.v2.dataset
 import cPickle
 import glob
+import cPickle as pickle
+import random
 
 __all__ = [
     'DATA_HOME', 'download', 'md5file', 'split', 'cluster_files_reader',
@@ -170,8 +172,6 @@ def convert(output_path,
             name_prefix,
             max_lines_to_shuffle=1000):
     import recordio
-    import cPickle as pickle
-    import random
     """
     Convert data from reader to recordio format files.
 
@@ -201,8 +201,10 @@ def convert(output_path,
     def write_data(w, lines):
         random.shuffle(lines)
         for i, d in enumerate(lines):
-            d = pickle.dumps(d, pickle.HIGHEST_PROTOCOL)
-            w[i % num_shards].write(d)
+            # FIXME(Yancey1989):
+            # dumps with protocol: pickle.HIGHEST_PROTOCOL
+            o = pickle.dumps(d)
+            w[i % num_shards].write(o)
 
     w = open_writers()
     lines = []
diff --git a/python/paddle/v2/dataset/mq2007.py b/python/paddle/v2/dataset/mq2007.py
index fd71b341662ca6f540ce44a86348e782561a97d7..cffb319ad8f56ccddba3fef63e1b6ec68e5bac1e 100644
--- a/python/paddle/v2/dataset/mq2007.py
+++ b/python/paddle/v2/dataset/mq2007.py
@@ -212,19 +212,19 @@ def gen_pair(querylist, partial_order="full"):
         for j in range(i + 1, len(querylist)):
             query_right = querylist[j]
             if query_left.relevance_score > query_right.relevance_score:
-                labels.append(1)
+                labels.append([1])
                 docpairs.append([
                     np.array(query_left.feature_vector),
                     np.array(query_right.feature_vector)
                 ])
             elif query_left.relevance_score < query_right.relevance_score:
-                labels.append(1)
+                labels.append([1])
                 docpairs.append([
                     np.array(query_right.feature_vector),
                     np.array(query_left.feature_vector)
                 ])
     for label, pair in zip(labels, docpairs):
-        yield label, pair[0], pair[1]
+        yield np.array(label), pair[0], pair[1]
 
 
 def gen_list(querylist):
diff --git a/python/paddle/v2/master/client.py b/python/paddle/v2/master/client.py
index 70f9e43c9683033233d48a750668771a4c7ba045..4c041fb509903008a7a5648a112b2472ed856aea 100644
--- a/python/paddle/v2/master/client.py
+++ b/python/paddle/v2/master/client.py
@@ -10,8 +10,9 @@ class client(object):
     client is a client to the master server.
     """
 
-    def __init__(self, addr, buf_size):
-        self.c = lib.paddle_new_master_client(addr, buf_size)
+    def __init__(self, etcd_endpoints, timeout, buf_size):
+        self.c = lib.paddle_new_etcd_master_client(etcd_endpoints, timeout,
+                                                   buf_size)
 
     def close(self):
         lib.paddle_release_master_client(self.c)
diff --git a/python/paddle/v2/optimizer.py b/python/paddle/v2/optimizer.py
index b6ee51cfe899fd0652fd3bf702ddcb440c3c7566..7e8a3bece9acb93ffba634e7b3656f2b580a48f2 100644
--- a/python/paddle/v2/optimizer.py
+++ b/python/paddle/v2/optimizer.py
@@ -1,3 +1,4 @@
+import py_paddle.swig_paddle as swig_api
 import paddle.trainer_config_helpers.config_parser_utils as config_parser_utils
 import paddle.trainer_config_helpers.optimizers as v1_optimizers
 """
@@ -16,7 +17,6 @@ __all__ = [
 
 class Optimizer(object):
     def __init__(self, **kwargs):
-        import py_paddle.swig_paddle as swig_api
         if 'batch_size' in kwargs:
             del kwargs['batch_size']  # not important for python library.
 
@@ -46,12 +46,12 @@ class Optimizer(object):
         return swig_api.ParameterUpdater.createRemoteUpdater(
             self.__opt_conf__, pass_num, use_sparse_updater)
 
-    def __create_new_remote_updater__(self, pserver_spec):
+    def __create_new_remote_updater__(self, pserver_spec, use_etcd):
         return swig_api.ParameterUpdater.createNewRemoteUpdater(
-            self.__opt_conf__, pserver_spec)
+            self.__opt_conf__, pserver_spec, use_etcd)
 
     def create_updater(self, is_local, num_passes, use_sparse_updater,
-                       pserver_spec):
+                       pserver_spec, use_etcd):
         """
         create proper parameter_updater by configuration.
         :param is_local: create local or remote parameter updater
@@ -77,7 +77,7 @@ class Optimizer(object):
                     num_passes, use_sparse_updater)
             else:
                 parameter_updater = self.__create_new_remote_updater__(
-                    pserver_spec)
+                    pserver_spec, use_etcd)
         return parameter_updater
 
 
diff --git a/python/paddle/v2/trainer.py b/python/paddle/v2/trainer.py
index 92fdf98e9030993cc9f250b2f9e6317073cb49de..76bae0bb12b6c33f88530386f9cc19ae9b59f457 100644
--- a/python/paddle/v2/trainer.py
+++ b/python/paddle/v2/trainer.py
@@ -45,7 +45,8 @@ class SGD(object):
                  update_equation,
                  extra_layers=None,
                  is_local=True,
-                 pserver_spec=None):
+                 pserver_spec=None,
+                 use_etcd=True):
 
         if not isinstance(parameters, v2_parameters.Parameters):
             raise TypeError('parameters should be parameters')
@@ -61,6 +62,7 @@ class SGD(object):
         self.__topology_in_proto__ = topology.proto()
         self.__is_local__ = is_local
         self.__pserver_spec__ = pserver_spec
+        self.__use_etcd__ = use_etcd
 
         self.__use_sparse_updater__ = self.__topology__.use_sparse_updater()
         # # In local mode, disable sparse_remote_update.
@@ -127,7 +129,7 @@ class SGD(object):
 
         self.__parameter_updater__ = self.__optimizer__.create_updater(
             self.__is_local__, num_passes, self.__use_sparse_updater__,
-            self.__pserver_spec__)
+            self.__pserver_spec__, self.__use_etcd__)
         self.__parameter_updater__.init(self.__gradient_machine__)
 
         self.__gradient_machine__.start()