The problem with cold cache pages
Every time your cache gets flushed — after a deployment, a content update, or a scheduled expiry — the next visitor hits an uncached page. Your server has to regenerate it from scratch: database queries, template rendering, full PHP execution. The result? A page that can be 3 to 10 times slower than a cached response.
This is bad for your users. But it's especially bad for your SEO.
Why Google cares about TTFB
Google's Core Web Vitals — specifically LCP (Largest Contentful Paint) — are direct ranking signals, and TTFB (Time to First Byte) is the foundation LCP is built on: a slow first byte delays everything that follows. Googlebot doesn't get special treatment: when it crawls a cold page, it measures the same slow response time your users see.
Akamai's research found that 100ms of added load time correlated with a 7% drop in conversion rate. For search engines, slow crawl times can reduce crawl budget and lower page scores in ranking algorithms.
The cache warming solution
Cache warming means pre-loading your pages before visitors (or crawlers) arrive. Instead of waiting for the first request to build the cache, you send a warm-up request to each URL after every flush — filling the cache so that all subsequent requests get the fast, cached version.
Deploy → Cache flush → CacheBoost warms URLs → First real visitor hits warm cacheWith CacheBoost, this happens automatically:
- You configure a boost pointing at your XML sitemap
- You set a schedule (cron expression) or trigger it via the API after each deploy
- CacheBoost crawls all your URLs from one or more regions, filling the cache
What gets warmed
A typical setup warms:
- All pages listed in your XML sitemap
- Multiple user-agent variants (desktop, mobile, Googlebot, GPTBot)
- From multiple geographic regions if you have a CDN
This ensures that both your real users and search engine crawlers always hit a warm, fast cache.
Measuring the impact
After enabling cache warming, check your:
- TTFB in Google Search Console (Page Experience report)
- LCP scores in Core Web Vitals
- Cache hit ratio in your CDN or reverse proxy dashboard
Most teams see a measurable improvement in Core Web Vitals within a few weeks — especially after deploy events that previously caused traffic spikes on cold pages.
Getting started
CacheBoost offers a free plan with 500 URLs per month — enough to get started with any small to medium site. Add your sitemap, configure your first boost, and your cache stays warm automatically.