diff --git a/python/freetoken/server/launch.py b/python/freetoken/server/launch.py
index a5f843886..e12f0934e 100644
--- a/python/freetoken/server/launch.py
+++ b/python/freetoken/server/launch.py
@@ -55,10 +55,20 @@ def _run_tokenize_worker(detach: bool, **kwargs) -> None:
     tokenize_worker(**kwargs)
 
 
+def _configure_worker_tqdm_lock() -> None:
+    import threading
+
+    from tqdm import tqdm
+
+    tqdm.set_lock(threading.RLock())
+
+
 def _run_scheduler(args: ServerArgs, ack_queue: mp.Queue[str]) -> None:
     if args.shell_mode:
         _detach_process_group()
 
+    _configure_worker_tqdm_lock()
+
     import torch
     from freetoken.scheduler import Scheduler