Tenzir Node Unreleased

🐞 Bug Fixes

Deterministic periodic summarize output

Apr 16, 2026 · @mavam, @codex

The summarize operator now starts frequency-based emission with the first input event and emits overdue periodic results before later events are aggregated. This makes periodic output deterministic in reset, cumulative, and update modes for delayed or sparse streams.

For example:

from {ts: 0ms.from_epoch(), x: 1},
     {ts: 90ms.from_epoch(), x: 1},
     {ts: 360ms.from_epoch(), x: 1}
delay ts
summarize count=count(), options={frequency: 300ms, mode: "cumulative"}

The first periodic result now consistently reports a count of 2 before the third event arrives.