diff --git a/demo-serving/op/ctr_prediction_op.cpp b/demo-serving/op/ctr_prediction_op.cpp
index 8e0e6fc0ec1f82262a4dedc2dd0ccc3c2331b6d4..806dbc7c87b20271d68c7c0c590c889d4dff622e 100644
--- a/demo-serving/op/ctr_prediction_op.cpp
+++ b/demo-serving/op/ctr_prediction_op.cpp
@@ -15,6 +15,9 @@
 #include "demo-serving/op/ctr_prediction_op.h"
 #include <algorithm>
 #include <string>
+#if 1
+#include <iomanip>
+#endif
 #include "cube/cube-api/include/cube_api.h"
 #include "predictor/framework/infer.h"
 #include "predictor/framework/kv_manager.h"
@@ -56,13 +59,6 @@ void fill_response_with_message(Response *response,
   return;
 }
 
-std::string str_tolower(std::string s) {
-  std::transform(s.begin(), s.end(), s.begin(), [](unsigned char c) {
-    return std::tolower(c);
-  });
-  return s;
-}
-
 int CTRPredictionOp::inference() {
   const Request *req = dynamic_cast<const Request *>(get_request_message());
 
@@ -123,6 +119,26 @@ int CTRPredictionOp::inference() {
         return -1;
       }
     }
+
+#if 1
+    for (int i = 0; i < keys.size(); ++i) {
+      std::ostringstream oss;
+      oss << keys[i] << ": ";
+      const char *value = (values[i].buff.data());
+      if (values[i].buff.size() !=
+          sizeof(float) * CTR_PREDICTION_EMBEDDING_SIZE) {
+        LOG(WARNING) << "Key " << keys[i] << " has values less than "
+                     << CTR_PREDICTION_EMBEDDING_SIZE;
+      }
+
+      for (int j = 0; j < values[i].buff.size(); ++j) {
+        oss << std::hex << std::uppercase << std::setw(2) << std::setfill('0')
+            << (reinterpret_cast<int>(value[j]) & 0xff);
+      }
+
+      LOG(INFO) << oss.str().c_str();
+    }
+#endif
   }
 
   // Sparse embeddings
diff --git a/predictor/framework/resource.cpp b/predictor/framework/resource.cpp
index eadf123f38c215972edad85ee4da9be862f59fef..29c5b20765c99cd4d9223ea845326f032f726a06 100644
--- a/predictor/framework/resource.cpp
+++ b/predictor/framework/resource.cpp
@@ -15,7 +15,6 @@
 #include "predictor/framework/resource.h"
 #include <string>
 #include "predictor/common/inner_common.h"
-#include "predictor/framework/infer.h"
 #include "predictor/framework/kv_manager.h"
 namespace baidu {
 namespace paddle_serving {
diff --git a/predictor/framework/resource.h b/predictor/framework/resource.h
index 9640888f91181826eb04faa03f5e73fdaecb346f..56e6bc2e8f748219409310e54744c755c81617a0 100644
--- a/predictor/framework/resource.h
+++ b/predictor/framework/resource.h
@@ -18,6 +18,7 @@
 #include "cube/cube-api/include/cube_api.h"
 #include "kvdb/paddle_rocksdb.h"
 #include "predictor/common/inner_common.h"
+#include "predictor/framework/infer.h"
 #include "predictor/framework/memory.h"
 
 namespace baidu {
@@ -37,7 +38,13 @@ struct DynamicResource {
 
 class Resource {
  public:
-  Resource() {}
+  Resource() {
+    // Reference InferManager::instance() explicitly, to make sure static
+    // instance of InferManager is constructed before that of Resource, and
+    // destruct after that of Resource
+    // See https://stackoverflow.com/a/335746/1513460
+    InferManager::instance();
+  }
 
   ~Resource() { finalize(); }