# A single consumer can't keep up with a 16-partition topic and lag is growing

Canonical URL: <https://datadriven.io/problems/a-single-consumer-cant-keep-up-with-a-16-partition-topic-an-ef348ea2>

Domain: Pipeline Design · Difficulty: medium

## Problem

A single consumer can't keep up with a 16-partition topic and lag is growing. Naively running two copies makes both read everything and double-process. Design consumption that scales horizontally without double-processing or losing offsets on restart.

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