diff --git a/go/pserver/cclient/cclient.go b/go/pserver/cclient/cclient.go
index be16a143d8ec4f54b9525d8d2941d4e8307336b6..7fdf9f0ec20b1e65a86845c03cd9e46e4847941f 100644
--- a/go/pserver/cclient/cclient.go
+++ b/go/pserver/cclient/cclient.go
@@ -42,7 +42,6 @@ import (
 	"strings"
 	"sync"
 	"unsafe"
-	"fmt"
 
 	"github.com/PaddlePaddle/Paddle/go/pserver"
 )
diff --git a/go/pserver/cclient/test/CMakeLists.txt b/go/pserver/cclient/test/CMakeLists.txt
index 762772812f532b78a3b741b9c74d8997541d31d1..e7d0a74237e9cd049cff96ff0589c53cfb329e7f 100644
--- a/go/pserver/cclient/test/CMakeLists.txt
+++ b/go/pserver/cclient/test/CMakeLists.txt
@@ -2,6 +2,8 @@ cmake_minimum_required(VERSION 3.0)
 
 add_executable(main main.c)
 add_dependencies(main paddle_pserver_cclient)
+add_executable(test_cclient test_cclient.c)
+add_dependencies(test_cclient paddle_pserver_cclient)
 
 if(APPLE)
   set(CMAKE_EXE_LINKER_FLAGS "-framework CoreFoundation -framework Security")
@@ -10,7 +12,9 @@ endif()
 if(PROJ_ROOT)
   include_directories(${CMAKE_BINARY_DIR}/go/pserver/cclient/)
   target_link_libraries(main ${CMAKE_BINARY_DIR}/go/pserver/cclient/libpaddle_pserver_cclient.a pthread)
+  target_link_libraries(test_cclient ${CMAKE_BINARY_DIR}/go/pserver/cclient/libpaddle_pserver_cclient.a pthread)
 else(PROJ_ROOT)
   include_directories(${CMAKE_BINARY_DIR})
   target_link_libraries(main ${CMAKE_BINARY_DIR}/libpaddle_pserver_cclient.a pthread)
+  target_link_libraries(test_cclient ${CMAKE_BINARY_DIR}/libpaddle_pserver_cclient.a pthread)
 endif(PROJ_ROOT)
diff --git a/go/pserver/cclient/test/main.c b/go/pserver/cclient/test/main.c
index 59cf5756fde34dd0720a919ca67450156f3f3665..a074808b16a85d732762d81343a47878a6ee0efa 100644
--- a/go/pserver/cclient/test/main.c
+++ b/go/pserver/cclient/test/main.c
@@ -1,5 +1,4 @@
 #include <stdio.h>
-#include <stdlib.h>
 
 #include "libpaddle_pserver_cclient.h"
 
@@ -10,21 +9,6 @@ void fail() {
   exit(-1);
 }
 
-void print_parameter(paddle_gradient* param) {
-  if (param == NULL) {
-    printf("param is NULL!!\n");
-  } else {
-    printf("==== parameter ====\n");
-    printf("name: %s\n", param->name);
-    printf("content_len: %d\n", param->content_len);
-    printf("content_type: %d\n", param->element_type);
-    for (int i = 0; i < param->content_len; ++i) {
-      printf("0x%x ", param->content[i]);
-    }
-    printf("\n\n");
-  }
-}
-
 int main() {
   char addr[] = "localhost:3000";
   client c = paddle_new_pserver_client(addr, 1);
@@ -33,23 +17,21 @@ retry:
     paddle_parameter param;
     char name_a[] = "param_a";
     char name_b[] = "param_b";
-    unsigned char content1[] = {0x01, 0x02, 0x03};
+    unsigned char content[] = {0x00, 0x11, 0x22};
     param.element_type = PADDLE_ELEMENT_TYPE_FLOAT32;
     param.name = name_a;
-    param.content = content1;
+    param.content = content;
     param.content_len = 3;
     if (paddle_init_param(c, param, NULL, 0) != 0) {
       goto retry;
     }
-    unsigned char content2[] = {0x04, 0x05, 0x06};
     param.element_type = PADDLE_ELEMENT_TYPE_INT32;
     param.name = name_b;
-    param.content = content2;
+    param.content = content;
     param.content_len = 3;
     if (paddle_init_param(c, param, NULL, 0) != 0) {
       goto retry;
     }
-
     if (paddle_finish_init_params(c) != 0) {
       goto retry;
     }
@@ -57,27 +39,22 @@ retry:
     fail();
   }
 
-  unsigned char content1[] = {0x12, 0x23, 0x34};
-  unsigned char content2[] = {0x45, 0x56, 0x67};
-
-  paddle_gradient** new_params =
-      (paddle_gradient**)malloc(sizeof(paddle_gradient*) * 2);
-  new_params[0] = (paddle_gradient*)malloc(sizeof(paddle_gradient));
-  new_params[0]->name = "param_a";
-  new_params[0]->content = content1;
-  new_params[0]->content_len = 3;
-  new_params[0]->element_type = PADDLE_ELEMENT_TYPE_FLOAT32;
-
-  new_params[1] = (paddle_gradient*)malloc(sizeof(paddle_gradient));
-  new_params[1]->name = "param_b";
-  new_params[1]->content = content2;
-  new_params[1]->content_len = 3;
-  new_params[1]->element_type = PADDLE_ELEMENT_TYPE_INT32;
-
-  print_parameter(new_params[0]);
-  print_parameter(new_params[1]);
-
-  if (paddle_send_grads(c, new_params, 2) != 0) {
+  unsigned char content[] = {0x00, 0x11, 0x22};
+  paddle_gradient** grads =
+          (paddle_gradient**)malloc(sizeof(paddle_gradient*) * 2);
+  grads[0] = (paddle_gradient*)malloc(sizeof(paddle_gradient));
+  grads[0]->name = "param_a";
+  grads[0]->content = content;
+  grads[0]->content_len = 3;
+  grads[0]->element_type = PADDLE_ELEMENT_TYPE_FLOAT32;
+
+  grads[1] = (paddle_gradient*)malloc(sizeof(paddle_gradient));
+  grads[1]->name = "param_b";
+  grads[1]->content = content;
+  grads[1]->content_len = 3;
+  grads[1]->element_type = PADDLE_ELEMENT_TYPE_INT32;
+
+  if (paddle_send_grads(c, grads, 2) != 0) {
     fail();
   }
 
@@ -87,15 +64,6 @@ retry:
     fail();
   }
 
-  print_parameter(params[0]);
-  print_parameter(params[1]);
-
-  /// change name of parameter.
-  char* names2[] = {"param_1", "param_2"};
-  if (paddle_get_params(c, names2, params, 2) == 0) {
-    fail();
-  }
-
   // get parameters again by reusing the allocated parameter buffers.
   if (paddle_get_params(c, names, params, 2) != 0) {
     fail();
@@ -109,5 +77,6 @@ retry:
   }
 
   printf("test success!\n");
+
   return 0;
 }
diff --git a/go/pserver/cclient/test/test_cclient.c b/go/pserver/cclient/test/test_cclient.c
new file mode 100644
index 0000000000000000000000000000000000000000..4d6fca29fbeb1ac597e54e2eb7ab55ac4389cf0e
--- /dev/null
+++ b/go/pserver/cclient/test/test_cclient.c
@@ -0,0 +1,114 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "libpaddle_pserver_cclient.h"
+
+typedef float real;
+
+void fail() {
+  // TODO(helin): fix: gtest using cmake is not working, using this
+  // hacky way for now.
+  printf("test failed.\n");
+  exit(-1);
+}
+
+void print_parameter(paddle_gradient* param) {
+  if (param == NULL) {
+    printf("param is NULL!!\n");
+  } else {
+    printf("==== parameter ====\n");
+    printf("name: %s\n", param->name);
+    printf("content_len: %d\n", param->content_len);
+    printf("content_type: %d\n", param->element_type);
+    for (int i = 0; i < param->content_len/sizeof(real); ++i) {
+      printf("%f ", ((float *)param->content)[i]);
+    }
+    printf("\n\n");
+  }
+}
+
+int main() {
+  char addr[] = "localhost:3000";
+  client c = paddle_new_pserver_client(addr, 1);
+
+  char* names[] = {"param_a", "param_b"};
+retry:
+
+  if (paddle_begin_init_params(c)) {
+    paddle_parameter param;
+    real param_content1[] = {0.1, 0.2, 0.3};
+    param.element_type = PADDLE_ELEMENT_TYPE_FLOAT32;
+    param.name = names[0];
+    param.content = (unsigned char*)param_content1;
+    param.content_len = 3 * sizeof(real);
+    if (paddle_init_param(c, param, NULL, 0) != 0) {
+      goto retry;
+    }
+    real param_content2[] = {0.4, 0.5, 0.6};
+    param.element_type = PADDLE_ELEMENT_TYPE_INT32;
+    param.name = names[1];
+    param.content = (unsigned char*)param_content2;
+    param.content_len = 3 * sizeof(real);
+    if (paddle_init_param(c, param, NULL, 0) != 0) {
+      goto retry;
+    }
+
+    if (paddle_finish_init_params(c) != 0) {
+      goto retry;
+    }
+  } else {
+    fail();
+  }
+
+  printf("get initialized parameters from pserver:\n");
+  paddle_parameter* param_ptrs[2] = {NULL, NULL};
+  if (paddle_get_params(c, names, param_ptrs, 2) != 0) {
+    fail();
+  }
+  print_parameter(param_ptrs[0]);
+  print_parameter(param_ptrs[1]);
+
+  printf("send gradient to pserver:\n");
+  real gradient_content1[] = {0.01, 0.02, 0.03};
+  real gradinet_content2[] = {0.04, 0.05, 0.06};
+
+  paddle_gradient** grads =
+      (paddle_gradient**)malloc(sizeof(paddle_gradient*) * 2);
+  grads[0] = (paddle_gradient*)malloc(sizeof(paddle_gradient));
+  grads[0]->name = names[0];
+  grads[0]->content = (unsigned char*)gradient_content1;
+  grads[0]->content_len = 3 * sizeof(real);
+  grads[0]->element_type = PADDLE_ELEMENT_TYPE_FLOAT32;
+
+  grads[1] = (paddle_gradient*)malloc(sizeof(paddle_gradient));
+  grads[1]->name = names[1];
+  grads[1]->content = (unsigned char*)gradinet_content2;
+  grads[1]->content_len = 3 * sizeof(real);
+  grads[1]->element_type = PADDLE_ELEMENT_TYPE_INT32;
+
+  print_parameter(grads[0]);
+  print_parameter(grads[1]);
+
+  if (paddle_send_grads(c, grads, 2) != 0) {
+    fail();
+  }
+
+  printf("get updated parameters from pserver:\n");
+  // get parameters again by reusing the allocated parameter buffers.
+  if (paddle_get_params(c, names, param_ptrs, 2) != 0) {
+    fail();
+  }
+
+  print_parameter(param_ptrs[0]);
+  print_parameter(param_ptrs[1]);
+
+  paddle_release_param(param_ptrs[0]);
+  paddle_release_param(param_ptrs[1]);
+
+  if (paddle_save_model(c, "/tmp/") != 0) {
+    fail();
+  }
+
+  printf("test success!\n");
+  return 0;
+}
diff --git a/go/pserver/optimizer.c b/go/pserver/optimizer.c
index b8da3ec9592053e3efe00e69d73a8ae259a30a2f..5d0b1017ce38c65831943e0d9339476b6537c62c 100644
--- a/go/pserver/optimizer.c
+++ b/go/pserver/optimizer.c
@@ -32,7 +32,13 @@ int update_SGD(void* optimizer,
                const void* gradient,
                int num_bytes) {
   SGD_optimizer* o = (SGD_optimizer*)optimizer;
-  // TODO
+  // TODO(a simple SGD implement)
+  float* parameter = (float *)buffer;
+  float* grad = (float *)gradient;
+
+  for(int i = 0; i < num_bytes/sizeof(float); ++i) {
+    parameter[i] -= o->learning_rate * grad[i];
+  }
   return 0;
 }
 
diff --git a/paddle/trainer/NewRemoteParameterUpdater.cpp b/paddle/trainer/NewRemoteParameterUpdater.cpp
index 35df973897b859671436faa73e283c149d401197..0f879dbde0ace90957995ee98357aadb7fe7282b 100644
--- a/paddle/trainer/NewRemoteParameterUpdater.cpp
+++ b/paddle/trainer/NewRemoteParameterUpdater.cpp
@@ -73,8 +73,6 @@ void NewRemoteParameterUpdater::init(
 void NewRemoteParameterUpdater::updateImpl(Parameter *para) {}
 
 void NewRemoteParameterUpdater::finishBatch(real cost) {
-  LOG(INFO) << "finishBatch in, cost: " << cost;
-
   // send gradient to parameter server.
   paddle_send_grads(parameterClient_, newGradients_, parameterSize());
   // get the updated parameter from parameterClient.
diff --git a/paddle/trainer/NewRemoteParameterUpdater.h b/paddle/trainer/NewRemoteParameterUpdater.h
index 1dbb3658fbe771067e8c7f6eb96b0a3d5dec65cf..d3a032badc9f928fbb91147b33b8f9702f07e71f 100644
--- a/paddle/trainer/NewRemoteParameterUpdater.h
+++ b/paddle/trainer/NewRemoteParameterUpdater.h
@@ -87,7 +87,7 @@ private:
       new_params[i]->name = (char*)param->getName().c_str();
       new_params[i]->content =
           (unsigned char*)(param->getBuf(type).get()->getData());
-      new_params[i]->content_len = (int)param->getBuf(type).get()->getSize();
+      new_params[i]->content_len = (int)param->getBuf(type).get()->getSize() * sizeof(real);
     }
     return new_params;
   }