This week in caching: a cache-warming runbook for launch day

This week in caching: a cache-warming runbook for launch day

Don't let your first real visitors pay for every cold miss. Run this before you announce.

— Crawl your own sitemap — a simple wget --quiet -i sitemap-urls.txt or a headless crawler populates the page cache ahead of traffic.
— Warm in priority order — homepage, top landing pages, then long tail; if the warm-up gets cut short, the important pages are already hot.
— Pre-render representative variants — if you cache per device or per format, warm each variant, not just desktop.
— Warm object/DB cache too — hit the endpoints that fill Redis, not just the HTML edge; a warm page cache over a cold object cache still stalls on first dynamic call.
— Check Age headers afterward — a populated cache shows a nonzero Age; zero everywhere means your warm-up didn't stick.

Credit to the cache-preload features in WP Rocket and Cloudflare's prefetch guidance.

Bookmark: a tiny sitemap-to-curl warming script — the WP and static crowds both reuse it.