diff --git a/llumnix/backends/vllm/llm_engine.py b/llumnix/backends/vllm/llm_engine.py
index b6e48591..5d20c2d2 100644
--- a/llumnix/backends/vllm/llm_engine.py
+++ b/llumnix/backends/vllm/llm_engine.py
@@ -13,6 +13,7 @@
 
 import os
 import time
+import traceback
 from typing import Any, List, Optional, Dict, Union, Iterable, Tuple
 from collections import defaultdict
 import threading
@@ -244,6 +245,7 @@ def _start_engine_loop(self) -> None:
             # pylint: disable=broad-except
             except Exception as e:
                 logger.error("Error in engine loop: {}".format(e))
+                logger.error("exception traceback: {}".format(traceback.format_exc()))
                 # pylint: disable=protected-access
                 os._exit(1)