diff --git a/core/sdk-cpp/include/abtest.h b/core/sdk-cpp/include/abtest.h
index 9964164c269cdda2c0e9b18dc4143edfe6db94d3..4833325416cfd6418bf33444001917d887f08cc0 100644
--- a/core/sdk-cpp/include/abtest.h
+++ b/core/sdk-cpp/include/abtest.h
@@ -45,7 +45,28 @@ class EndpointRouterBase {
 class WeightedRandomRender : public EndpointRouterBase {
  public:
   static int register_self() {
-    INLINE_REGIST_OBJECT(WeightedRandomRender, EndpointRouterBase, -1);
+    // INLINE_REGIST_OBJECT(WeightedRandomRender, EndpointRouterBase, -1);
+
+    Factory<WeightedRandomRender, EndpointRouterBase>* factory =
+        new (std::nothrow) Factory<WeightedRandomRender, EndpointRouterBase>();
+    if (factory == NULL) {
+      RAW_LOG_ERROR(
+          "Failed regist factory: WeightedRandomRender->EndpointRouterBase in "
+          "macro!");
+      return -1;
+    }
+
+    // When two clients are created in the same process, two
+    // "WeightedRandomRender" factory objects are registered.
+    // But in fact, the two clients can use one factory object
+    // together.
+    if (FactoryPool<EndpointRouterBase>::instance().register_factory(
+            "WeightedRandomRender", factory) != 0) {
+      RAW_LOG_INFO(
+          "Factory has been registed: "
+          "WeightedRandomRender->EndpointRouterBase.");
+    }
+
     return 0;
   }
 
diff --git a/python/paddle_serving_client/__init__.py b/python/paddle_serving_client/__init__.py
index f3d6a9a661e494bbf8f3ea9995c8e9139fd102d5..acece304414d8b5ebf7f1937cfa495c58e7ac60d 100644
--- a/python/paddle_serving_client/__init__.py
+++ b/python/paddle_serving_client/__init__.py
@@ -156,7 +156,9 @@ class Client(object):
                 )
         else:
             if self.predictor_sdk_ is None:
-                self.add_variant('var1', endpoints, 100)
+                timestamp = time.time()
+                self.add_variant('default_tag_{}'.format(timestamp), endpoints,
+                                 100)
             else:
                 print(
                     "parameter endpoints({}) will not take effect, because you use the add_variant function.".