Convert a single-flight panic into an error

- flightGroup.Do recovers a panicking fn so the leader and every waiter get a non-nil error instead of a zero-value success served as 200 [] - Note in the README that facts_cache_bytes budgets body bytes only
2026-09-05 20:55:09 +10:00
parent ac3c19143a
commit c9fe2fbc4c
3 changed files with 187 additions and 2 deletions
@@ -117,7 +117,9 @@ backend later without further handler changes.
 - **Bounded** — `facts_cache_bytes` (default 64 MiB) is a byte budget, evicted
  least-recently-used; reads count as use, so a stale entry that is still being
  asked for survives. A single response larger than the whole budget is not
-  cached at all.
+  cached at all. The budget counts stored response bodies only — cache keys and
+  the list/map bookkeeping are not accounted for, so it is a target for body
+  bytes rather than a hard cap on process memory.
 - **Single-flight** — concurrent requests for the same key collapse into one
  upstream fan-out; the rest wait for it and share the result.
 - **Visibility** — `/healthz` carries a `cache` object: `backend`