FastAPI's def vs async def: A Blocking Call Freezes Every Request
FastAPI's async def vs def usage can lead to performance issues. Key considerations for proper implementation.
A recent change in FastAPI that converted all endpoints to async def led to unexpected outages. This shift did not honor the async contract, causing latency spikes across all endpoints. Understanding the distinction between async and def is crucial for maintaining performance, as async endpoints must not block the event loop to ensure smooth operation.