SAA-C03 Design High-Performing Architectures Practice Question

Exhibit

CloudWatch summary for app servers:
- Average CPUUtilization: 24%
- Average MemoryUtilization: 91%
- Average NetworkIn/Out: low
- Current instance type: m6i.large
- User reports: application slows when more sessions are active

Based on the exhibit, the team wants to improve application performance without changing the code. Which EC2 instance family should they choose next?

⚠ Common exam trap

Test-takers frequently assume 'improving performance' always means faster CPU or storage, but the exhibit’s memory utilization metric directly points to a memory bottleneck, making the memory-optimized family the correct choice despite the lack of explicit code changes.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Choose a memory-optimized instance family such as R6i to provide more RAM.

The exhibit shows that the application is experiencing high memory utilization (e.g., memory pressure or swapping), which degrades performance. Choosing a memory-optimized instance family such as R6i provides more RAM per vCPU, directly addressing the bottleneck without requiring code changes. This improves application performance by reducing or eliminating swap usage and allowing more data to be cached in memory.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Choose a compute-optimized instance family such as C6i to increase CPU performance.
Why it's wrong here
Compute-optimized instances help when CPU is the bottleneck, but this workload shows low CPU usage and high memory usage.
✓
Choose a memory-optimized instance family such as R6i to provide more RAM.
Why this is correct
Memory-optimized instances are the best fit when memory pressure is causing slowdowns. The exhibit shows CPU is low while memory is consistently near saturation, which strongly suggests the application needs more RAM rather than more compute. Moving to an R6i family should reduce paging and improve response times without changing the application design.
✗
Choose a storage-optimized instance family such as I4i to improve block storage throughput.
Why it's wrong here
Storage-optimized instances are useful for high I/O workloads, but the exhibit does not show storage latency or throughput as the issue.
✗
Choose a burstable instance family such as T3 to reduce cost and improve performance.
Why it's wrong here
Burstable instances are not a good fix for sustained memory pressure. They are intended for variable, low-average CPU workloads, not memory shortages.

Go deeper

SAA-C03 Design High-Performing Architectures Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

Related to this question