Deduplication window.
also: dedup window · deduplication windows · idempotency TTLHow long processed IDs or idempotency keys are remembered; it must outlast every possible retry.
the two-minute refresher
- Forever is too long: storage grows without bound and legitimate re-submissions are blocked.
- Too short is useless: a 10 s TTL can't protect a request that times out at 30 s.
- Rule of thumb from the lesson: at least 10× your maximum retry window.
- Store what you need to replay: status, response, and a hash of the request.