From b6909aa223b18acc1172093f22f8db0ea4365f7f Mon Sep 17 00:00:00 2001
From: ishandhanani <82981111+ishandhanani@users.noreply.github.com>
Date: Sat, 17 May 2025 18:32:41 -0700
Subject: [PATCH] fix: allow `launch_dummy_health_check_server` to start inside
 of running asyncio loop (#6330)

---
 python/sglang/srt/utils.py | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/python/sglang/srt/utils.py b/python/sglang/srt/utils.py
index 9cbea8252..828b23039 100644
--- a/python/sglang/srt/utils.py
+++ b/python/sglang/srt/utils.py
@@ -1847,6 +1847,8 @@ def get_cuda_version():
 
 
 def launch_dummy_health_check_server(host, port):
+    import asyncio
+
     import uvicorn
     from fastapi import FastAPI, Response
 
@@ -1862,13 +1864,27 @@ def launch_dummy_health_check_server(host, port):
         """Check the health of the http server."""
         return Response(status_code=200)
 
-    uvicorn.run(
+    config = uvicorn.Config(
         app,
         host=host,
         port=port,
         timeout_keep_alive=5,
-        loop="uvloop",
+        loop="auto",
+        log_config=None,
+        log_level="warning",
     )
+    server = uvicorn.Server(config=config)
+
+    try:
+        loop = asyncio.get_running_loop()
+        logger.info(
+            f"Dummy health check server scheduled on existing loop at {host}:{port}"
+        )
+        loop.create_task(server.serve())
+
+    except RuntimeError:
+        logger.info(f"Starting dummy health check server at {host}:{port}")
+        server.run()
 
 
 def create_checksum(directory: str):