diff --git a/cpp/src/metrics/Metrics.cpp b/cpp/src/metrics/Metrics.cpp
index 925bb4cd5c..23fb0a15b8 100644
--- a/cpp/src/metrics/Metrics.cpp
+++ b/cpp/src/metrics/Metrics.cpp
@@ -3,36 +3,29 @@
  * Unauthorized copying of this file, via any medium is strictly prohibited.
  * Proprietary and confidential.
  ******************************************************************************/
-
-
 #include "Metrics.h"
 #include "PrometheusMetrics.h"
 
+
 namespace zilliz {
 namespace milvus {
 namespace server {
 
 MetricsBase &
-Metrics::CreateMetricsCollector(MetricCollectorType collector_type) {
-    switch (collector_type) {
-        case MetricCollectorType::PROMETHEUS:
-            static PrometheusMetrics instance = PrometheusMetrics::GetInstance();
-            return instance;
-        default:return MetricsBase::GetInstance();
-    }
+Metrics::GetInstance() {
+    static MetricsBase &instance = CreateMetricsCollector();
+    return instance;
 }
 
 MetricsBase &
-Metrics::GetInstance() {
+Metrics::CreateMetricsCollector() {
     ConfigNode &config = ServerConfig::GetInstance().GetConfig(CONFIG_METRIC);
-    std::string collector_typr_str = config.GetValue(CONFIG_METRIC_COLLECTOR);
+    std::string collector_type_str = config.GetValue(CONFIG_METRIC_COLLECTOR);
 
-    if (collector_typr_str == "prometheus") {
-        return CreateMetricsCollector(MetricCollectorType::PROMETHEUS);
-    } else if (collector_typr_str == "zabbix") {
-        return CreateMetricsCollector(MetricCollectorType::ZABBIX);
+    if (collector_type_str == "prometheus") {
+        return PrometheusMetrics::GetInstance();
     } else {
-        return CreateMetricsCollector(MetricCollectorType::INVALID);
+        return MetricsBase::GetInstance();
     }
 }
 
diff --git a/cpp/src/metrics/Metrics.h b/cpp/src/metrics/Metrics.h
index be796eb9c4..65df7140cc 100644
--- a/cpp/src/metrics/Metrics.h
+++ b/cpp/src/metrics/Metrics.h
@@ -5,22 +5,14 @@
  ******************************************************************************/
 #pragma once
 
-#include "utils/Error.h"
-#include <memory>
-#include <vector>
-
-
-#pragma once
-
 #include "MetricBase.h"
-//#include "PrometheusMetrics.h"
+
 
 namespace zilliz {
 namespace milvus {
 namespace server {
 
 #define METRICS_NOW_TIME std::chrono::system_clock::now()
-//#define server::Metrics::GetInstance() server::Metrics::GetInstance()
 #define METRICS_MICROSECONDS(a, b) (std::chrono::duration_cast<std::chrono::microseconds> (b-a)).count();
 
 enum class MetricCollectorType {
@@ -31,15 +23,13 @@ enum class MetricCollectorType {
 
 class Metrics {
  public:
-    static MetricsBase &
-    CreateMetricsCollector(MetricCollectorType collector_type);
+    static MetricsBase &GetInstance();
 
-    static MetricsBase &
-    GetInstance();
+ private:
+    static MetricsBase &CreateMetricsCollector();
 };
 
 
-
 }
 }
 }
diff --git a/cpp/src/server/grpc_impl/GrpcRequestTask.cpp b/cpp/src/server/grpc_impl/GrpcRequestTask.cpp
index 49dfd07330..95ceaffd42 100644
--- a/cpp/src/server/grpc_impl/GrpcRequestTask.cpp
+++ b/cpp/src/server/grpc_impl/GrpcRequestTask.cpp
@@ -459,7 +459,8 @@ InsertTask::OnExecute() {
                                         std::to_string(table_info.dimension_);
                 return SetError(error_code, error_msg);
             }
-            memcpy(static_cast<void *>(&vec_f[i * table_info.dimension_]), static_cast<const void *>(insert_param_.row_record_array(i).vector_data().data()),
+            memcpy(&vec_f[i * table_info.dimension_],
+                   insert_param_.row_record_array(i).vector_data().data(),
                    table_info.dimension_ * sizeof(float));
         }
 
@@ -472,8 +473,7 @@ InsertTask::OnExecute() {
             vec_ids[i] = insert_param_.row_id_array(i);
         }
 
-        stat = DBWrapper::DB()->InsertVectors(insert_param_.table_name(), vec_count, vec_f.data(),
-                                              vec_ids);
+        stat = DBWrapper::DB()->InsertVectors(insert_param_.table_name(), vec_count, vec_f.data(), vec_ids);
         rc.ElapseFromBegin("add vectors to engine");
         if (!stat.ok()) {
             return SetError(SERVER_CACHE_ERROR, "Cache error: " + stat.ToString());