AWS Certified Solutions Architect – Professional — Question 340

In Amazon RDS for PostgreSQL, you can provision up to 3TB storage and 30,000 IOPS per database instance. For a workload with 50% writes and 50% reads running on a cr1.8xlarge instance, you can realize over 25,000 IOPS for PostgreSQL. However, by provisioning more than this limit, you may be able to achieve:

Answer options

• A. higher latency and lower throughput.
• B. lower latency and higher throughput.
• C. higher throughput only.
• D. higher latency only.

Correct answer: B

Explanation

Over-provisioning storage and IOPS on Amazon RDS for PostgreSQL allows the database to process I/O operations more efficiently, which reduces the time it takes to complete requests and increases the volume of data processed per second. Therefore, this configuration helps achieve lower latency and higher throughput. Choosing any other combination would imply degraded performance or incomplete optimization.