Glossary coding Term Page
Keep-Alive Timeout
Duration a server holds persistent HTTP connections before closing them when no data flows.
Core Idea
Keep-alive timeout is the interval an HTTP server (like uvicorn or a load balancer) waits before closing an otherwise idle connection. Streaming workloads and SSE keep sockets open even though data may pause momentarily, so low timeouts cause premature disconnects and half-delivered responses.
Why It Matters Here
Mathbong’s FastAPI lessons highlight that streaming APIs are only stable when the keep-alive timeout is tuned to outlast the expected stream duration. Raising it to match StreamingResponse workloads prevents browsers from retrying mid-download and keeps SSE feeds alive.