spring-boot-scheduling

name	spring-boot-scheduling
description	Standards for scheduled tasks and distributed locking with ShedLock. Use when implementing @Scheduled tasks or distributed locking with ShedLock in Spring Boot. (triggers: **/*Scheduler.java, **/*Job.java, scheduled, shedlock, cron)

Spring Boot Scheduling Standards

Priority: P0

Implementation Guidelines

Scheduled Tasks

• ThreadPool: ALWAYS configure a dedicated TaskScheduler (default is 1 thread). Enable with @EnableScheduling annotation.
• Async: Keep @Scheduled methods light; offload to @Async/Queues. Wrap logic in try/catch; log errors and use @Retryable for retry on transient failures.

Distributed Locking (ShedLock)

• Problem: @Scheduled runs on ALL pods in K8s.
• Solution: Use ShedLock to guarantee single execution.
• Config: Set lockAtMostFor (deadlock safety) and lockAtLeastFor (debounce).

Anti-Patterns

• No Default Pool: Configure dedicated TaskScheduler (default is 1 thread).
• No duplicates: Use ShedLock for distributed cron in multi-pod deployments.
• No task state: Design tasks to be idempotent; assume pod can restart.

References

• Implementation Examples