Glossary · HTTP, edge and rendering
cache split
The state in which a bare request for a URL and a cache-busted request for the same URL return different answers: a different status, a different content type, or different bytes. A single fetch cannot see it; two can.
What cache split means
The state in which a bare request for a URL and a cache-busted request for the same URL return different answers: a different status, a different content type, or different bytes. A single fetch cannot see it; two can. A split on a machine file means what a crawler receives depends on cache state rather than on the site.
What cache split can and cannot support
| It can support | It cannot support |
|---|---|
| The state in which a bare request for a URL and a cache-busted request for the same URL return different answers: a different status, a different content type, or different bytes. | A single fetch cannot see it; two can. A split on a machine file means what a crawler receives depends on cache state rather than on the site. |
How CrawlCheck measures cache split
2 finding codes in the scanner read this. The share of all scans carrying each is computed from the live corpus when this page is served, not typed into it.
| Finding code | Share of scans | Guide |
|---|---|---|
MACHINE_FILE_CACHE_STALE | 0.7% | Does llms.txt actually do anything? |
MACHINE_FILE_CACHE_SPLIT | 0.1% | Does llms.txt actually do anything? |
Every code, its rule and its current rate: the dataset page. Scan a site to see which apply to it.
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.
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 · Cache key · 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-buster · Cache-Control · Age header · render-blocking resource · payload text share · lazy loading · 404 and 410 status codes
Questions about cache split
What is cache split?
The state in which a bare request for a URL and a cache-busted request for the same URL return different answers: a different status, a different content type, or different bytes. A single fetch cannot see it; two can.
What does cache split not show or guarantee?
A single fetch cannot see it; two can. A split on a machine file means what a crawler receives depends on cache state rather than on the site.
How does CrawlCheck measure cache split?
Through the finding codes MACHINE_FILE_CACHE_STALE, MACHINE_FILE_CACHE_SPLIT, each with a stated rule, evidence bytes and a live share of scans on the dataset page.
Which area of the glossary does cache split 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.
← edge cache · cache-buster →
See it in the full glossary · 668 terms across 19 areas.