Allowed lateness.
also: late data · late-arriving data · late events · side output · side outputsHow long a window keeps its state after firing so late events can still update it; anything later is dropped or side-output.
the two-minute refresher
- The window fires at the watermark, then accepts late updates for the allowed lateness.
- Each update re-emits a corrected result downstream.
- After that, state is cleaned up; later events go to a side output for reprocessing.
- Longer lateness = more correct, more memory held.