diff --git a/tests/benchmark/milvus_benchmark/runners/locust.py b/tests/benchmark/milvus_benchmark/runners/locust.py
index 607c9d8362..b734a4d36e 100644
--- a/tests/benchmark/milvus_benchmark/runners/locust.py
+++ b/tests/benchmark/milvus_benchmark/runners/locust.py
@@ -94,6 +94,7 @@ class LocustInsertRunner(LocustRunner):
         }
         self.init_metric(self.name, collection_info, index_info, None, run_params)
         case_metric = copy.deepcopy(self.metric)
+        # set metric type as case
         case_metric.set_case_metric_type()
         case_metrics = list()
         case_params = list()