Cloudflare R2 custom domain

Range request BYPASS vs. MISS vs. HIT

Measures time to first byte for the same bounded byte range when cache is explicitly bypassed, when it first fills Cloudflare cache, and when it is subsequently served from cache, at five positions in one 500 MB object.

Range bytes Rounds

BYPASS is a direct ranged R2 binding read, so it never enters the custom-domain CDN cache. Each custom-domain position uses a fresh cache key for a real MISS followed by a HIT. A run can initiate five large edge-cache fills.

Ready.

BYPASS median payload TTFB

direct R2 binding

MISS median payload TTFB

first range body byte

HIT median payload TTFB

first range body byte

HIT vs BYPASS

Position	Offset	BYPASS header	BYPASS payload	MISS payload	HIT payload	BYPASS/HIT	MISS/HIT	Statuses

Methodology

For every row the Worker first reads the bounded range through its R2 binding as the cache-bypass baseline and verifies the returned range and byte count. It then creates a unique custom-domain query key, sends Range with Accept-Encoding: identity, verifies a 206 response and exact Content-Range, and fully consumes only the bounded range. The first custom-domain response must report MISS; the Worker then probes the identical URL for the first verified HIT.