Cache - Pingora now powers Cloudflare's cache

Cloudflare's cache now runs on a new proxy built on Pingora , the Rust-based framework that already serves a significant portion of Cloudflare's network traffic. The new proxy is faster, more memory-safe, and designed to evolve our cache architecture. It delivers immediate performance improvements and enables new caching capabilities. What this brings Lower latency : The new proxy reduces per-request overhead through improved connection reuse. Reduced cache MISSes : Enhanced cache retention improves origin offload. Better RFC compliance : Caching behavior more closely follows HTTP caching standards. Foundation for future features : The new architecture enables upcoming improvements to cache functionality and efficiency. New features Asynchronous stale-while-revalidate : Every request returns stale content immediately while revalidation happens in the background, instead of the first request after expiry blocking on the origin. Refer to the asynchronous stale-while-revalidate changelog for details. Unbuffered bypass by default : Responses that bypass cache are streamed directly to the client without buffering, reducing time-to-first-byte for uncacheable content. Behavioral changes The new architecture introduces the following behavioral changes to improve RFC compliance and correctness: Vary: * results in cache bypass : According to RFC 9110 Section 12.5.5 , a Vary header value of * indicates the response varies on factors beyond request headers and must not be served from cache. Cloudflare now bypasses cache for these responses instead of storing them. Set-Cookie stripped on MISS and EXPIRED : For cacheable assets, Set-Cookie is now stripped on MISS and EXPIRED responses, not only on HITs. Floating-point TTL values : Floating-point time-to-live values (for example, max-age=1.5 ) are rounded down to the nearest integer instead of being rejected as invalid. What's next A deeper look at the new cache proxy is coming soon to the Cloudflare blog . For background on the underlying framework, read: Open sourcing Pingora: our Rust framework for building programmable network services How we built Pingora, the proxy that connects Cloudflare to the Internet