Design a Job Scheduler

Advanced · 24 min read · Low-Level Design, Case Studies: Advanced

Time-ordered queue, a dispatcher that sleeps until due, fixed rate vs delay, retries and cancellation.

This is an Advanced lesson, part of Premium. What it covers:

• What the interviewer expects
• 1. Requirements
• 2. Design
• 3. The dispatcher: sleep until the next job, wake early when needed
• 4. Running, rescheduling and retrying
• 5. Cancellation without searching the heap
• 6. Concurrency summary
• 7. Patterns used
• 8. Extensions
• Interview questions
• Further reading

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