# Peak Concurrent Batch Jobs

> Jobs pile up. Find the moment the scheduler sweats the most.

Canonical URL: <https://datadriven.io/problems/peak_concurrent_batch_jobs>

Domain: SQL · Difficulty: medium · Seniority: L4

## Problem

The scheduler team is sizing capacity by finding the worst pile-up. A job is running between its start and end time. Return the largest number of jobs that were running at the same instant, as a single number. If a job ends and another starts at the exact same time, treat the ending one as finishing first.

## Related

- [All practice problems](https://datadriven.io/problems)
- [Mock interview mode](https://datadriven.io/interview/peak_concurrent_batch_jobs)
- [SQL Interview Questions](https://datadriven.io/sql-interview-questions)
- [Data Engineering Interview Prep Guide](https://datadriven.io/data-engineer-interview-prep)
- [Daily Challenge](https://datadriven.io/daily)

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