diff --git a/demo-serving/conf/model_toolkit.prototxt b/demo-serving/conf/model_toolkit.prototxt
index c3f618d104461b6aeef13173aaf482e0538f50af..fae40a9dd0b4c19225cedd8bad42aea43bd1c5d7 100644
--- a/demo-serving/conf/model_toolkit.prototxt
+++ b/demo-serving/conf/model_toolkit.prototxt
@@ -45,4 +45,5 @@ engines {
   runtime_thread_num: 0
   batch_infer_size: 0
   enable_batch_align: 0
+  enable_memory_optimization: true
 }