Most Cost-Effective EC2 Option for Interruptible Batch Workloads
A company has batch workloads that need to run for short periods of time on Amazon EC2. The workloads can handle interruptions and can start again from where they ended. What is the MOST cost-effective EC2 instance purchasing option to meet these requirements?
Community Votes
100% of anonymous learners picked answer B. Votes are pick records left by other test-takers — they are not the verified answer.
Community Insight
The question tests mapping workload traits—tolerance for interruption and resumability—to the cheapest EC2 purchasing option, and the trap is choosing a discount model like Reserved Instances that actually requires a long-term commitment.
Amazon EC2 Spot Instances let you use spare AWS capacity at steep discounts for interruptible, resumable batch workloads, making them the most cost-effective choice here. This page confirms why option B fits the scenario and rules out commitment-based or dedicated pricing.
A common mistake is picking Reserved Instances (A) simply because they are cheaper than On-Demand; however, they demand a 1- or 3-year commitment and do not match short, interruptible batch jobs.
Community Discussion (6 comments)
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Expert Analysis
Why the Answer Is Correct
Spot Instances let you request spare Amazon EC2 capacity at discounts of up to 90% compared with On-Demand. AWS can reclaim that capacity when demand rises, but the question explicitly says the workloads can handle interruptions and can restart from where they ended—exactly the fault-tolerant, checkpointable pattern Spot pricing is built for. Because the requirement is the MOST cost-effective option for short, flexible runs, Spot Instances (B) are the intended answer. Amazon EC2 Spot also integrates with capacity-optimized allocation and Auto Scaling to reduce interruption impact, reinforcing its fit for batch jobs.Why the Other Options Are Wrong
Reserved Instances (A) give a billing discount only in exchange for a 1- or 3-year commitment, which is wasteful for intermittent short jobs. Dedicated Instances (C) provide hardware isolation for compliance or licensing reasons and carry a premium price that contradicts the cost-effectiveness goal. On-Demand Instances (D) have no commitment but are far more expensive than Spot for workloads that can tolerate interruption. None of A, C, or D match the combination of short duration, interruption tolerance, and lowest cost that the stem describes.Community Comment Notes
Learners in the comments overwhelmingly chose B, with ShaiTay explaining that Spot is "most cost effective and can handle interruptions" and another learner noting "its b because its interruptable." One commenter, KhanhNT, suggested A, which reflects the common mix-up between a commitment-based discount and the best fit for flexible usage. The discussion reinforces that the deciding factor is the stem's explicit statement that the workloads can be interrupted and resumed.Official Reference
Exam Strategy
When the stem mentions 'can handle interruptions' and asks for the MOST cost-effective option, scan the choices for Spot Instances first. Eliminate Reserved Instances and Dedicated Instances unless the workload is steady-state or requires hardware isolation.
Frequently Asked Questions
Why are Reserved Instances not the most cost-effective choice for this batch workload?
Reserved Instances trade a 1- or 3-year commitment for a discount on steady-state usage; they do not reward short, interruptible jobs the way Spot Instances do.
Can Spot Instances handle workloads that restart from where they left off?
Yes—Spot interruptions include a two-minute warning, and batch jobs that checkpoint can resume, which is exactly the fault-tolerant pattern Spot pricing is designed for.
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