AWS Certified Solutions Architect – Associate (SAA-C02) — Question 638

A company hosts an application on an Amazon EC2 instance that requires a maximum of 200 GB storage space. The application is used infrequently, with peaks during mornings and evenings. Disk I/O varies, but peaks at 3,000 IOPS. The chief financial officer of the company is concerned about costs and has asked a solutions architect to recommend the most cost-effective storage option that does not sacrifice performance.
Which solution should the solutions architect recommend?

Answer options

• A. Amazon Elastic Block Store (Amazon EBS) Cold HDD (sc1)
• B. Amazon Elastic Block Store (Amazon EBS) General Purpose SSD (gp2)
• C. Amazon Elastic Block Store (Amazon EBS) Provisioned IOPS SSD (io1)
• D. Amazon Elastic Block Store (Amazon EBS) Throughput Optimized HDD (st1)

Correct answer: B

Explanation

Amazon EBS gp2 volumes smaller than 1 TiB can burst up to 3,000 IOPS, making it the most cost-effective option that satisfies the application's peak I/O demands. Provisioned IOPS SSD (io1) would also meet the performance requirements but at a significantly higher cost. HDD-based volumes like sc1 and st1 are designed for throughput rather than high IOPS and cannot support the 3,000 IOPS peak.