# A sessionization job uses processing-time windows, so when ingestion lags, events land in the wrong

Canonical URL: <https://datadriven.io/problems/a-sessionization-job-uses-processing-time-windows-so-when-i-47920e8e>

Domain: Pipeline Design · Difficulty: medium

## Problem

A sessionization job uses processing-time windows, so when ingestion lags, events land in the wrong session and metrics jump around. Design windowing that is correct regardless of when events are processed.

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