The Partition Increase That Raised the BillKafka · medium · ~12 minTwo weeks ago the platform team raised the clickstream topic from 100 to 250 partitions to "unlock consumer parallelism for the future."Throughput hasn't changed. But network transfer is up ~40%, request rate quadrupled, storage is growing measurably faster — and the finance dashboard noticed before anyone on-call did. Nothing is erroring. Find the mechanism.Evidence

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Throughput is flat but network, requests, and storage all jumped at hour 2. What's the mechanism?

Which chart pair proves the diagnosis in one glance?

What's the cheapest correct fix, given null keys and no ordering requirement?

The team still believes 250 partitions is the right long-term call. Write the review you'd send: when a partition increase is justified, what it costs, and what you'd verify before and after.