Retrieval Service efficiency optimization (langgenius#13543)

Author: charli117

api/configs/middleware/__init__.py

@@ -1,3 +1,4 @@
+import os
 from typing import Any, Literal, Optional
 from urllib.parse import quote_plus
 
@@ -166,6 +167,11 @@ def SQLALCHEMY_DATABASE_URI(self) -> str:
         default=False,
     )
 
+    RETRIEVAL_SERVICE_WORKER: NonNegativeInt = Field(
+        description="If True, enables the retrieval service worker.",
+        default=os.cpu_count(),
+    )
+
     @computed_field
     def SQLALCHEMY_ENGINE_OPTIONS(self) -> dict[str, Any]:
         return {