Everything you ever wanted to know about UDP sockets but were afraid to ask, part 1
Nov 25, 2021Marek Majkowski

Summary
This post delves into the complexities of operating stateful UDP services at scale, a critical component for modern protocols like QUIC and services like WARP and Spectrum. It details the nuances of connected vs. unconnected UDP sockets, the challenges of sourcing packets from wildcard sockets, and introduces the 'established-over-unconnected' technique as a method for graceful server restarts in UDP. This contributes to the understanding and optimization of Cloudflare's underlying network infrastructure for handling diverse and high-performance UDP traffic.
More from the Hardware Infrastructure & Performance Optimization trail
- How we reduced core unit boot time from hours to minutes
- A one-line Kubernetes fix that saved 600 hours a year
- Inside Gen 13- how we built our most powerful server yet
- Launching Cloudflare’s Gen 13 servers- trading cache for cores for 2x edge compute performance
- So long, and thanks for all the fish- how to escape the Linux networking stack