Issues with Async Database Queries in FastAPI Using SQLAlchemy - Connection Timeout Errors
I'm currently working on a FastAPI application that interacts with a PostgreSQL database using SQLAlchemy, and I'm running into connection timeout issues when executing async queries. My setup is using FastAPI version 0.68.0 and SQLAlchemy version 1.4.22. The application is designed to handle multiple concurrent requests, but I frequently encounter `asyncio.exceptions.TimeoutError` when querying data from the database. I have defined an asynchronous database session within my application like this: ```python from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine from sqlalchemy.orm import sessionmaker DATABASE_URL = 'postgresql+asyncpg://user:password@localhost/dbname' engine = create_async_engine(DATABASE_URL, echo=True) AsyncSessionLocal = sessionmaker(bind=engine, class_=AsyncSession, expire_on_commit=False) ``` And my endpoint to fetch user data looks like this: ```python from fastapi import FastAPI, Depends from sqlalchemy.ext.asyncio import AsyncSession app = FastAPI() async def get_db_session() -> AsyncSession: async with AsyncSessionLocal() as session: yield session @app.get('/users/{user_id}') async def read_user(user_id: int, db: AsyncSession = Depends(get_db_session)): query = await db.execute(select(User).where(User.id == user_id)) user = query.scalars().first() return user ``` When I run the application and make requests to this endpoint, everything works fine for a while, but after some concurrent requests, I start getting these timeout errors. I've tried increasing the connection pool size and the timeout settings in the database configuration, but the issue persists. Here's how I configured the connection pool: ```python engine = create_async_engine(DATABASE_URL, echo=True, pool_pre_ping=True, pool_size=20, max_overflow=10) ``` Is there something I'm missing in my setup, or is there a recommended approach to handle this type of async database interaction in FastAPI? Any advice would be greatly appreciated! This is part of a larger API I'm building. Any help would be greatly appreciated!