SAP-C02 Question 525
Select 2A company runs a web application on 50 Amazon EC2 instances in a single AWS Region. The application has a predictable and steady workload throughout the year, with occasional 10% spikes in traffic during the holiday season. The company wants to reduce its overall compute costs without compromising performance. Which combination of pricing models would best achieve this goal?
- A
Purchase Reserved Instances for 50 EC2 instances for a 1-year term.
- B
Utilize Savings Plans for the predictable baseline workload and use On-Demand Instances for traffic spikes.
- C
Run the entire workload on Spot Instances to minimize costs.
- D
Use a combination of Reserved Instances for the steady workload and Spot Instances for the spikes.
- E
Use On-Demand Instances for the steady workload and Spot Instances for the spikes.
Show answer and explanation
Correct answers: B, D
Explanation
The company has a predictable, steady workload and occasional traffic spikes. A combination of Savings Plans or Reserved Instances for the baseline workload and Spot Instances for the spikes maximizes cost efficiency. Savings Plans are more flexible and cover multiple instance types and regions, while Spot Instances provide low-cost options for intermittent demands. Both approaches ensure cost savings and meet the application's performance requirements.
- A. Incorrect.
Purchasing Reserved Instances for 50 EC2 instances would lock in capacity and a lower rate. However, it is not flexible for spikes in traffic and may result in underutilized resources during non-spike periods, leading to inefficiencies.
- B. Correct.
Savings Plans provide flexibility across instance families and Availability Zones while offering significant cost savings for predictable workloads. On-Demand Instances can complement this by handling occasional spikes, ensuring cost-effectiveness and scalability.
- C. Incorrect.
Running the entire workload on Spot Instances could lead to significant cost savings but is highly unreliable for steady workloads, as Spot Instances can be interrupted at any time.
- D. Correct.
Using a combination of Reserved Instances for the steady workload and Spot Instances for the spikes balances cost savings and flexibility. Reserved Instances provide cost-efficient, long-term capacity, and Spot Instances can handle temporary spikes at a lower cost.
- E. Incorrect.
Using On-Demand Instances for both steady workloads and spikes would be the most expensive option, as On-Demand pricing is the highest among all models. It does not align with the goal of reducing overall costs.