Cache key
The values a cache uses to decide which stored response matches a request.
What Cache key does not show
Missing a relevant dimension can serve one client’s variant to another.
Where Cache key comes up on this site
- Stale cached robots.txt or llms.txt? Two fetches tell youGET /robots.txt bare, as a crawler asks GET /robots.txt?cc=x7k2p cache-busted Edge cache stored copy answers Edge cache key misses, passes on Origin the file as it is now Compare status, type, bytes If the two answers differ, the edge and the origin…
- robots.txt returns 200 but no crawler can read itA cache key is built from the URL and a few headers; it has no way to know a 200 is a challenge.
Terms this definition uses
Related terms in HTTP, edge and rendering
The delivery layer between an origin and a client: proxies, caches, redirects, status codes and the headers that decide what a crawler actually received.
Content-Language header · HTTP/3 · Alt-Svc · HTTPS DNS record · Link header · content negotiation · Markdown negotiation · Retry-After · Server-Timing · WWW-Authenticate · Allow header · Content-Digest · Origin server · Reverse proxy · CDN · Edge node · WAF · Bot score · TLS handshake · DNS resolution · DNS timeout · Connection timeout · Read timeout · Redirect chain · Redirect loop · 301 redirect · 302 redirect · 307 redirect · 308 redirect · 304 response · 404 response · 410 response · 429 response · 500 response · 502 response · 503 response · 504 response · HEAD request · GET request · Content type · MIME sniffing · Content encoding · Compression · Brotli · ETag · Last-Modified · If-None-Match · Cache hit · Cache miss · Vary header · Stale response · Stale-while-revalidate · Edge redirect · Origin bypass · Response parity · Header parity · hreflang · canonical URL · HSTS · HSTS preload list · Content-Security-Policy · CSP nonce · edge cache · cache split · cache-buster · Cache-Control · Age header · render-blocking resource · payload text share · lazy loading · 404 and 410 status codes
Questions about Cache key
What is Cache key?
The values a cache uses to decide which stored response matches a request.
What does Cache key not show or guarantee?
Missing a relevant dimension can serve one client’s variant to another.
Which area of the glossary does Cache key belong to?
HTTP, edge and rendering: The delivery layer between an origin and a client: proxies, caches, redirects, status codes and the headers that decide what a crawler actually received.
← Cache miss · Vary header →
See it in the full glossary · 772 terms across 19 areas.
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