Improving Smart Tiered Cache for Public Cloud Regions

In 2021, we shipped Smart Tiered Cache. The idea: for each origin behind your site, Cloudflare picks the single best upper-tier data center to route through, based on real-time latency. Flip one switch, and we find the fastest path from our network to your origin.

That works as long as an origin IP lives in one fixed place. Public cloud origins usually don't. They sit behind anycast or regional unicast front ends, so one origin IP can look equally close to a dozen Cloudflare data centers at once — and the latency probes have nothing to lock onto. Smart Tiered Cache handles this the safe way: when there's no clear winner, it falls back to several upper tiers. Nothing breaks. You just lose the thing that made a single closest tier worth it, which is cache efficiency.

Smart Tiered Cache for Public Cloud Regions fixes this by letting you provide a cloud region hint. With that hint, Cloudflare can map public cloud origins to the right region and select better primary and fallback upper tiers, even when the origin IP itself looks anycast or ambiguous.

Since it was launched, Smart Tiered Continue reading