How we halved DNS build delay and cut memory use by 85%
Summary
Cloudflare halved DNS build delay and cut memory usage by 85% by introducing a targeted build planner and a unified scheduler. The changes reduce full-zone rebuilds for large zones, with 92.95% of builds now targeted rather than full, and memory usage dropping from 49–79 GiB to around 7 GiB on average. The article includes metrics, diagrams, and safety tests (mirror testing) to validate correctness.