Cloudflare freed 100TB of RAM by cutting 1.1.1.1's DNS cache entries 56%
Cloudflare shrank each cache entry in Big Pineapple, the platform behind 1.1.1.1, from 953 to 420 bytes across 250 billion entries, freeing roughly 100 terabytes of memory — the RAM in 130 of its Gen 13 servers. The savings came from portable Rust choices: fixed-size Box types replacing growable Vec and String, the answer, authority, and additional sections merged into one list addressed by u16 offsets, and rare record variants such as NAPTR and SVCB boxed so the enum stops sizing to its largest member. Nothing was traded for it — insert throughput rose 43% to 893,000 entries per second and lookup latency fell 19% to 670 nanoseconds, with p99 memory per instance dropping from 9.3GB to 5.3GB over the 18 May to 6 July 2026 rollout.
Source: blog.cloudflare.com ↗
At that scale, wasting a single byte per entry costs more than 250 gigabytes of memory across our fleet.
Why this matters
- → 100TB RAM freed lets Cloudflare run same workload on 130 fewer servers.
- → Performance improved 43% insert throughput, 19% lower latency — no speed-for-space tradeoff.
- → Portable Rust optimization techniques (fixed-size Box, enum boxing, bitpacking) scale to massive systems.