Design a High-Frequency Job Scheduler
Company: Bytedance
Role: Software Engineer
Category: System Design
Difficulty: medium
Interview Round: Onsite
Design a distributed job scheduler that supports one-time and recurring jobs, including high-frequency tasks that may run every few seconds. The system should support priorities, retries, horizontal scaling, worker pools, and at-least-once delivery semantics.
Discuss:
- APIs and data model for scheduled jobs
- How jobs are stored and made durable
- How due jobs are discovered efficiently
- Priority-based dispatch to workers
- Retry handling, deduplication, and failure recovery
- How to scale the scheduler and workers under heavy load
- Monitoring and operational safety
Quick Answer: This question evaluates competency in distributed systems design, scheduling semantics (including high-frequency and recurring jobs), durable job storage and consistency, priority-based dispatching, retry and deduplication mechanisms, failure recovery, scalability of worker pools, and monitoring/operational safety.