Cloudflare KV Cache-Warming Doesn’t Work the Way You Think#

A common “obvious” optimization for Cloudflare KV: at the end of your deploy, write the top-N popular cache entries (search results, config blobs, computed views) so the cache is “warm” when production traffic arrives. This doesn’t do what you think.

KV writes go to central data stores only. Regional edges populate on first read in that region — and replication propagation adds up to 60 seconds. Writing from one Worker doesn’t push the value globally; subsequent first-reads in each region still pay the central-store fetch.