# A Spark job writes one tiny file per task, producing tens of thousands of small files per day

Canonical URL: <https://datadriven.io/problems/a-spark-job-writes-one-tiny-file-per-task-producing-tens-of-9aa5354c>

Domain: Pipeline Design · Difficulty: medium

## Problem

A Spark job writes one tiny file per task, producing tens of thousands of small files per day. Downstream reads are dominated by file-open overhead. Design output that writes right-sized files.

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