HardDesign: Distributed Task Scheduler (Cron at Scale)
What is the difference between 'at-least-once' and 'exactly-once' task execution?
— Tests your understanding of this concept.
Answer Options
AAt-least-once never skips, may run multiple times; exactly-once runs exactly once even under failures
BThey are equivalent in practice
CExactly-once is faster than at-least-once
DAt-least-once requires more infrastructure
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