Cloudflare saves 100TB of RAM by fixing a single algorithm
Saving another 100TB of RAM with math (and Rust)
Cloudflare's Pingora Backend Router was using up to 6GB of memory per node due to an explosion of consistent hashing rings. By shrinking the index in the hash point struct from 32 to 16 bits and applying mathematical analysis, the team reclaimed over 100TB of RAM globally—following another 100TB saved by the DNS team last month.
At this scale, small improvements are greatly magnified, so even 1%-at-a-time improvements are worth celebrating.