diff --git a/core/predictor/src/pdserving.cpp b/core/predictor/src/pdserving.cpp
index 24a3fa8a2f7763baa617b542fce4b6825065b680..f0fedacf63b250ec3dd742744dc01d67d567f653 100644
--- a/core/predictor/src/pdserving.cpp
+++ b/core/predictor/src/pdserving.cpp
@@ -99,8 +99,8 @@ static void g_change_server_port() {
   if (read_proto_conf(FLAGS_inferservice_path.c_str(),
                       FLAGS_inferservice_file.c_str(),
                       &conf) != 0) {
-    VLOG(WARNING) << "failed to load configure[" << FLAGS_inferservice_path
-                  << "," << FLAGS_inferservice_file << "].";
+    VLOG(2) << "failed to load configure[" << FLAGS_inferservice_path
+            << "," << FLAGS_inferservice_file << "].";
     return;
   }
   uint32_t port = conf.port();
diff --git a/core/sdk-cpp/include/stub_impl.hpp b/core/sdk-cpp/include/stub_impl.hpp
index 30a1feae88a496e3e5beeb39298831e5de5d6d8d..6fad5b5e2c702652126bc159333046790fcefc69 100644
--- a/core/sdk-cpp/include/stub_impl.hpp
+++ b/core/sdk-cpp/include/stub_impl.hpp
@@ -35,11 +35,11 @@ int StubImpl<T, C, R, I, O>::initialize(const VariantInfo& var,
     }
 
     _gchannel = init_channel(var, filter);
-    LOG(INFO) << "Create stub with tag: " << *tag << ", " << *tag_value
-              << ", ep: " << ep;
+    VLOG(2) << "Create stub with tag: " << *tag << ", " << *tag_value
+            << ", ep: " << ep;
   } else {
     _gchannel = init_channel(var, NULL);
-    LOG(INFO) << "Create stub without tag, ep " << ep;
+    VLOG(2) << "Create stub without tag, ep " << ep;
   }
 
   if (!_gchannel) {
@@ -143,7 +143,7 @@ int StubImpl<T, C, R, I, O>::thrd_initialize() {
     return -1;
   }
 
-  LOG(WARNING) << "Succ thread initialize stub impl!";
+  VLOG(2) << "Succ thread initialize stub impl!";
 
   return 0;
 }
@@ -370,7 +370,7 @@ google::protobuf::RpcChannel* StubImpl<T, C, R, I, O>::init_channel(
   // brpc parallel channel
   _pchannel = init_pchannel(_channel, _max_channel, _package_size, chn_options);
   if (_pchannel) {
-    LOG(INFO) << "Succ create parallel channel, count: " << _max_channel;
+    VLOG(2) << "Succ create parallel channel, count: " << _max_channel;
     return _pchannel;
   }
 
@@ -384,21 +384,21 @@ brpc::ParallelChannel* StubImpl<T, C, R, I, O>::init_pchannel(
     uint32_t package_size,
     const brpc::ChannelOptions& options) {
   if (channel_count <= 1) {  // noneed use parallel channel
-    LOG(INFO) << "channel count <= 1, noneed use pchannel.";
+    VLOG(2) << "channel count <= 1, noneed use pchannel.";
     return NULL;
   }
 
   _pchannel = butil::get_object<brpc::ParallelChannel>();
   if (!_pchannel) {
-    LOG(FATAL) << "Failed get pchannel from object pool";
+    VLOG(2) << "Failed get pchannel from object pool";
     return NULL;
   }
 
   brpc::ParallelChannelOptions pchan_options;
   pchan_options.timeout_ms = options.timeout_ms;
   if (_pchannel->Init(&pchan_options) != 0) {
-    LOG(FATAL) << "Failed init parallel channel with tmo_us: "
-               << pchan_options.timeout_ms;
+    VLOG(2) << "Failed init parallel channel with tmo_us: "
+            << pchan_options.timeout_ms;
     return NULL;
   }
 
diff --git a/core/sdk-cpp/src/abtest.cpp b/core/sdk-cpp/src/abtest.cpp
index de594048c65de4724b158405e827d4bd72645cb5..836dc25ffb1913dc62313d7c5cdeb85958850fe3 100644
--- a/core/sdk-cpp/src/abtest.cpp
+++ b/core/sdk-cpp/src/abtest.cpp
@@ -52,9 +52,9 @@ int WeightedRandomRender::initialize(const google::protobuf::Message& conf) {
       return -1;
     }
 
-    LOG(INFO) << "Succ read weights list: " << weights
-              << ", count: " << _variant_weight_list.size()
-              << ", normalized: " << _normalized_sum;
+    VLOG(2) << "Succ read weights list: " << weights
+            << ", count: " << _variant_weight_list.size()
+            << ", normalized: " << _normalized_sum;
   } catch (std::bad_cast& e) {
     LOG(ERROR) << "Failed init WeightedRandomRender"
                << "from configure, err:" << e.what();
@@ -87,9 +87,9 @@ Variant* WeightedRandomRender::route(const VariantList& variants) {
   for (uint32_t ci = 0; ci < cand_size; ++ci) {
     cur_total += _variant_weight_list[ci];
     if (sample < cur_total) {
-      LOG(INFO) << "Sample " << sample << " on " << ci
-                << ", _normalized: " << _normalized_sum
-                << ", weight: " << _variant_weight_list[ci];
+      VLOG(2) << "Sample " << sample << " on " << ci
+              << ", _normalized: " << _normalized_sum
+              << ", weight: " << _variant_weight_list[ci];
       return variants[ci];
     }
   }
diff --git a/core/sdk-cpp/src/config_manager.cpp b/core/sdk-cpp/src/config_manager.cpp
index 8bc9f9514a8e3b84ea053ccd3eccca899db36e60..c422f0b52eba7d3a34e663f4198b9914a7722704 100644
--- a/core/sdk-cpp/src/config_manager.cpp
+++ b/core/sdk-cpp/src/config_manager.cpp
@@ -80,8 +80,8 @@ int EndpointConfigManager::load(const std::string& sdk_desc_str) {
     LOG(ERROR) << "Failed load configure" << e.what();
     return -1;
   }
-  LOG(INFO) << "Success reload endpoint config file, id: "
-            << _current_endpointmap_id;
+  VLOG(2) << "Success reload endpoint config file, id: "
+          << _current_endpointmap_id;
   return 0;
 }
 
@@ -128,8 +128,8 @@ int EndpointConfigManager::load() {
     LOG(ERROR) << "Failed load configure" << e.what();
     return -1;
   }
-  LOG(INFO) << "Success reload endpoint config file, id: "
-            << _current_endpointmap_id;
+  VLOG(2) << "Success reload endpoint config file, id: "
+          << _current_endpointmap_id;
   return 0;
 }
 
@@ -181,8 +181,8 @@ int EndpointConfigManager::init_one_endpoint(const configure::Predictor& conf,
       return -1;
     }
 
-    LOG(INFO) << "Succ load one endpoint, name: " << ep.endpoint_name
-              << ", count of variants: " << ep.vars.size() << ".";
+    VLOG(2) << "Succ load one endpoint, name: " << ep.endpoint_name
+            << ", count of variants: " << ep.vars.size() << ".";
   } catch (std::exception& e) {
     LOG(ERROR) << "Exception acccurs when load endpoint conf"
                << ", message: " << e.what();
@@ -258,7 +258,7 @@ int EndpointConfigManager::merge_variant(const VariantInfo& default_var,
 int EndpointConfigManager::parse_tag_values(SplitParameters& split) {
   split.tag_values.clear();
   if (!split.split_tag.init || !split.tag_cands_str.init) {
-    LOG(WARNING) << "split info not set, skip...";
+    VLOG(2) << "split info not set, skip...";
     return 0;
   }
 
diff --git a/core/sdk-cpp/src/endpoint.cpp b/core/sdk-cpp/src/endpoint.cpp
index fb1e32d193cf618194bf2849a004cbc88c46cceb..fe0bf024a24c6a8d959bd0b96319027388457207 100644
--- a/core/sdk-cpp/src/endpoint.cpp
+++ b/core/sdk-cpp/src/endpoint.cpp
@@ -35,8 +35,8 @@ int Endpoint::initialize(const EndpointInfo& ep_info) {
       return -1;
     }
     _variant_list.push_back(var);
-    LOG(INFO) << "Succ create variant: " << vi
-              << ", endpoint:" << _endpoint_name;
+    VLOG(2) << "Succ create variant: " << vi
+            << ", endpoint:" << _endpoint_name;
   }
 
   return 0;
@@ -51,7 +51,7 @@ int Endpoint::thrd_initialize() {
       return -1;
     }
   }
-  LOG(WARNING) << "Succ thrd initialize all vars: " << var_size;
+  VLOG(2) << "Succ thrd initialize all vars: " << var_size;
   return 0;
 }
 
diff --git a/core/sdk-cpp/src/predictor_sdk.cpp b/core/sdk-cpp/src/predictor_sdk.cpp
index ae976446e7e074f0b0723d9d637ee7ff320b00be..c9f4a6944bb451093d3e84dcac3c13b43f29a9c6 100644
--- a/core/sdk-cpp/src/predictor_sdk.cpp
+++ b/core/sdk-cpp/src/predictor_sdk.cpp
@@ -25,7 +25,7 @@ int PredictorApi::register_all() {
     return -1;
   }
 
-  LOG(WARNING) << "Succ register all components!";
+  VLOG(2) << "Succ register all components!";
 
   return 0;
 }
@@ -66,8 +66,8 @@ int PredictorApi::create(const std::string & api_desc_str) {
       return -1;
     }
 
-    LOG(INFO) << "Succ create endpoint instance with name: "
-              << ep_info.endpoint_name;
+    VLOG(2) << "Succ create endpoint instance with name: "
+            << ep_info.endpoint_name;
   }
 
   return 0;
@@ -101,7 +101,7 @@ int PredictorApi::create(const char* path, const char* file) {
       return -1;
     }
 
-    LOG(INFO) << "endpoint name: " << ep_info.endpoint_name;
+    VLOG(2) << "endpoint name: " << ep_info.endpoint_name;
 
     std::pair<std::map<std::string, Endpoint*>::iterator, bool> r =
         _endpoints.insert(std::make_pair(ep_info.endpoint_name, ep));
@@ -110,8 +110,8 @@ int PredictorApi::create(const char* path, const char* file) {
       return -1;
     }
 
-    LOG(INFO) << "Succ create endpoint instance with name: "
-              << ep_info.endpoint_name;
+    VLOG(2) << "Succ create endpoint instance with name: "
+            << ep_info.endpoint_name;
   }
 
   return 0;
@@ -126,7 +126,7 @@ int PredictorApi::thrd_initialize() {
       return -1;
     }
 
-    LOG(WARNING) << "Succ thrd initialize endpoint:" << it->first;
+    VLOG(2) << "Succ thrd initialize endpoint:" << it->first;
   }
   return 0;
 }
@@ -152,7 +152,7 @@ int PredictorApi::thrd_finalize() {
       return -1;
     }
 
-    LOG(INFO) << "Succ thrd finalize endpoint:" << it->first;
+    VLOG(2) << "Succ thrd finalize endpoint:" << it->first;
   }
   return 0;
 }
diff --git a/core/sdk-cpp/src/variant.cpp b/core/sdk-cpp/src/variant.cpp
index c11d18285b5bec6bb8982bbfb3feb7b6879a073d..ae1d787bfc2bd3b4ca57eb9d8043cd40744b9c50 100644
--- a/core/sdk-cpp/src/variant.cpp
+++ b/core/sdk-cpp/src/variant.cpp
@@ -53,7 +53,7 @@ int Variant::initialize(const EndpointInfo& ep_info,
   }
 
   if (_stub_map.size() > 0) {
-    LOG(INFO) << "Initialize variants from VariantInfo"
+    VLOG(2) << "Initialize variants from VariantInfo"
               << ", stubs count: " << _stub_map.size();
     return 0;
   }
@@ -66,7 +66,7 @@ int Variant::initialize(const EndpointInfo& ep_info,
   }
 
   _default_stub = stub;
-  LOG(INFO) << "Succ create default debug";
+  VLOG(2) << "Succ create default debug";
   return 0;
 }
 
@@ -82,10 +82,10 @@ int Variant::thrd_initialize() {
       LOG(ERROR) << "Failed thrd initialize stub: " << iter->first;
       return -1;
     }
-    LOG(INFO) << "Succ thrd initialize stub:" << iter->first;
+    VLOG(2) << "Succ thrd initialize stub:" << iter->first;
   }
 
-  LOG(WARNING) << "Succ thrd initialize all stubs";
+  VLOG(2) << "Succ thrd initialize all stubs";
   return 0;
 }
 
diff --git a/python/examples/fit_a_line/local_train.py b/python/examples/fit_a_line/local_train.py
index 699ad7b67d5bb2a8f8937418a002e19991058473..fae6f72c7ddbd6d0d0e7c6742d1234ae4f6398cb 100644
--- a/python/examples/fit_a_line/local_train.py
+++ b/python/examples/fit_a_line/local_train.py
@@ -32,5 +32,5 @@ for pass_id in range(30):
             fetch_list=[avg_loss])
 
 serving_io.save_model(
-    "serving_server_model", "serving_client_conf",
-    {"x": x}, {"y": y_predict}, fluid.default_main_program())
+    "uci_housing_model", "uci_housing_client",
+    {"x": x}, {"price": y_predict}, fluid.default_main_program())
diff --git a/python/examples/imdb/local_train.py b/python/examples/imdb/local_train.py
index 9c65dc587ea8fe06753ef09dddaf8fc82f6ca5bf..d3d7c3bae25f2e6b996685eb70301dd3f939526f 100644
--- a/python/examples/imdb/local_train.py
+++ b/python/examples/imdb/local_train.py
@@ -46,18 +46,17 @@ if __name__ == "__main__":
     dataset.set_use_var([data, label])
     pipe_command = "python imdb_reader.py"
     dataset.set_pipe_command(pipe_command)
-    dataset.set_batch_size(4)
+    dataset.set_batch_size(128)
     dataset.set_filelist(filelist)
     dataset.set_thread(10)
-    from nets import cnn_net
-    avg_cost, acc, prediction = cnn_net(data, label, dict_dim)
+    from nets import bow_net
+    avg_cost, acc, prediction = bow_net(data, label, dict_dim)
     optimizer = fluid.optimizer.SGD(learning_rate=0.01)
     optimizer.minimize(avg_cost)
 
     exe = fluid.Executor(fluid.CPUPlace())
     exe.run(fluid.default_startup_program())
     epochs = 6
-    save_dirname = "cnn_model"
 
     import paddle_serving_client.io as serving_io
 
@@ -67,9 +66,5 @@ if __name__ == "__main__":
         logger.info("TRAIN --> pass: {}".format(i))
         if i == 5:
             serving_io.save_model("serving_server_model", "serving_client_conf",
-                                  {"words": data,
-                                   "label": label}, {
-                                       "cost": avg_cost,
-                                       "acc": acc,
-                                       "prediction": prediction
-                                   }, fluid.default_main_program())
+                                  {"words": data}, {"prediction": prediction},
+                                  fluid.default_main_program())