diff --git a/vllm/v1/worker/ubatching.py b/vllm/v1/worker/ubatching.py
index c0e44689d886e..47a681a6757b5 100644
--- a/vllm/v1/worker/ubatching.py
+++ b/vllm/v1/worker/ubatching.py
@@ -46,7 +46,7 @@ class UBatchContext:
         # self.stream.wait_event(start_event)
         print("Starting ubatch %d" % self.id)
         # if self.gpu_wait_on_launch:
-        #     self.gpu_stream_wait()
+        self.gpu_stream_wait()
         return self
 
     def __exit__(self, exc_type, exc_val, exc_tb):