Examkin

Question

Difficulty: HardAWS Pricing Models

A financial services startup is launching a mobile application and has two specific server requirements:

* The primary transaction processing API layer, which runs continuously and has a predictable baseline CPU utilization that will not change over the next year.
* An analytics job that runs nightly for 2 hours, performing data transformation. This job is stateless, fault-tolerant, and can be terminated mid-run and retried the next night without data loss.

Which two Amazon EC2 pricing models should the startup select to achieve the most cost-effective solution for these workloads? (Select TWO.)

  1. Savings Plans to run the continuous, predictable transaction processing API layerAnswer
  2. Spot Instances to run the fault-tolerant, stateless nightly analytics jobsAnswer
  3. C
    On-Demand Instances to run the baseline transaction processing API layer
  4. D
    Spot Instances to run the continuous transaction processing API layer
  5. E
    Reserved Instances to run the short-term, nightly analytics jobs

Answer

The startup should select Savings Plans for the continuous, predictable transaction processing API layer, and Spot Instances for the fault-tolerant, stateless nightly analytics jobs.
The correct choices are Savings Plans for the transaction API layer and Spot Instances for the nightly analytics jobs. Savings Plans offer substantial discounts for predictable, continuous compute usage over a 1-year or 3-year term, making them ideal for the API layer. Spot Instances offer the highest discounts for workloads that are flexible, fault-tolerant, and can tolerate interruptions, which perfectly fits the stateless nightly analytics jobs.

Step-by-Step Solution

1
Analyze the first workload requirement (transaction API layer).
The API runs continuously (24/7) with a predictable baseline for at least a year.
For predictable, long-term continuous workloads, committing to a Savings Plan or Reserved Instances provides a significant discount compared to On-Demand pricing.
2
Analyze the second workload requirement (analytics job).
The job runs nightly for 2 hours, is stateless, fault-tolerant, and can be terminated mid-run and retried.
Since the job can tolerate interruptions and runs briefly, Spot Instances are the most cost-effective choice, offering up to 90% off On-Demand rates without any long-term commitment.
3
Evaluate the options and identify the correct combination.
The correct selections are the options proposing Savings Plans for the API layer and Spot Instances for the nightly analytics jobs.
Other combinations either introduce high costs (using On-Demand for baseline API, or Reserved Instances for 2-hour daily jobs) or risk service disruption (using Spot Instances for the critical transactional API).

Key Concept

Selecting optimal AWS EC2 pricing models based on workload predictability, duration, and fault tolerance.
Estimated Time:2m 0s
Rate this question

Topics

AWS Pricing Models

More questions from this topic