Hard Design: Distributed Task Scheduler (Cron at Scale)
What happens if the ZooKeeper cluster used for leader election goes down?
— Tests your understanding of this concept.
Answer Options
A The scheduler continues normally
B No scheduler instance can become leader — no new tasks are enqueued until ZooKeeper recovers
C All instances become leaders simultaneously
D Tasks are executed directly from the database
Want to see the correct answer?
Get the answer with a detailed explanation, plus practice 22+ more Design: Distributed Task Scheduler (Cron at Scale) questions with adaptive quizzes and timed interviews.
See the Answer on Guru Sishya →This question is from the Design: Distributed Task Scheduler (Cron at Scale) topic (System Design Cases).
More Design: Distributed Task Scheduler (Cron at Scale) Questions
Why is a single-server cron scheduler not suitable for production at scale?
HardWhat is the purpose of leader election in a distributed task scheduler?
HardA worker picks up a task and starts executing. The worker crashes mid-execution. What happens?
HardWhat is the 'thundering herd' problem in a task scheduler?
HardHow do you calculate the next_run_at for a cron expression after a successful execution?
Hard