A relayed response from the upstream fallback (#20) is held in memory in full before being sent on. Inbound request bodies are capped at 256 MB; a relayed response has no ceiling at all, so a large dataset page or key-value record read through fallback is bounded only by available heap.
Streaming the body through would remove the asymmetry. A size cap is the cheaper interim option if streaming is not wanted yet — worth deciding which, rather than leaving it unbounded by default.
Follow-up named in that change's design; the reviewers raised the interim cap separately and could not settle it against the approved design either way.
A relayed response from the upstream fallback (#20) is held in memory in full before being sent on. Inbound request bodies are capped at 256 MB; a relayed response has no ceiling at all, so a large dataset page or key-value record read through fallback is bounded only by available heap.
Streaming the body through would remove the asymmetry. A size cap is the cheaper interim option if streaming is not wanted yet — worth deciding which, rather than leaving it unbounded by default.
Follow-up named in that change's design; the reviewers raised the interim cap separately and could not settle it against the approved design either way.