How Facebook is bringing QUIC to billions

What this post added

This post details Meta's implementation and deployment of QUIC and HTTP/3, detailing the development of their own QUIC implementation called mvfst. It highlights the technical challenges encountered, such as application logic regressions affecting static content delivery, CPU efficiency concerns with mvfst for static content, and the tuning of congestion control (BBR) and flow control parameters. The post quantifies the improvements seen in metrics like request errors, tail latency, and video rebuffering (MTBR) across Facebook and Instagram apps, emphasizing the benefits for users in emerging markets. It also discusses the integration of QUIC with existing infrastructure like Proxygen and network load balancers, and the strategy for rolling out the protocol to billions of users.