SAA-C03 Design High-Performing Architectures Practice Question
A research institution is running a High Performance Computing (HPC) workload on AWS that requires a POSIX-compliant file system capable of millions of IOPS and sub-millisecond latencies. Which TWO storage options are most appropriate for this use case?
⚠ Common exam trap
SAA-C03 often tests the difference between POSIX-compliant file systems and object storage, and candidates mistakenly select EFS or S3 for HPC workloads requiring millions of IOPS and sub-millisecond latency.
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
✓
Amazon FSx for Lustre.
Amazon FSx for Lustre (A) is correct because it is a POSIX-compliant, high-performance file system purpose-built for HPC, delivering millions of IOPS and sub-millisecond latencies, and it integrates with S3 for data staging. EC2 Instance Store with a clustered file system (D) is correct because instance store volumes are physically attached NVMe SSDs offering the lowest latency and highest IOPS, and a clustered file system (e.g., Lustre, GPFS) can aggregate them across nodes for shared POSIX access. Amazon S3 with S3 Select (B) is object storage, not POSIX-compliant, and cannot meet sub-millisecond latency requirements. Amazon FSx for Windows File Server (C) uses SMB and is designed for Windows workloads, not high-IOPS POSIX HPC. Amazon EFS General Purpose mode (E) is POSIX-compliant but its latency and throughput are far below the millions of IOPS and sub-millisecond requirements of this workload.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Amazon FSx for Lustre.
Why this is correct
FSx for Lustre is a high-performance file system optimized for workloads like HPC, machine learning, and video processing. It can provide hundreds of gigabytes per second of throughput and millions of IOPS, while also integrating seamlessly with S3 for long-term data storage.
- ✗
Amazon S3 with S3 Select.
Why it's wrong here
S3 Select allows applications to retrieve only a subset of data from an object, which can improve performance for certain queries. However, S3 is not a POSIX-compliant file system and cannot provide the sub-millisecond local latency required for high-performance computing clusters.
- ✗
Amazon FSx for Windows File Server.
Why it's wrong here
While FSx for Windows provides a managed file system, it is optimized for Windows-based workloads and SMB protocols. It does not offer the same level of extreme parallel performance or the Linux-native POSIX optimization that Lustre provides for HPC applications.
- ✓
EC2 Instance Store with a clustered file system.
Why this is correct
By using local Instance Store volumes on a cluster of EC2 instances and managing them with a clustered file system (like BeeGFS or GlusterFS), an organization can achieve the highest possible local I/O performance for temporary, high-speed data processing tasks.
- ✗
Amazon EFS in General Purpose mode.
Why it's wrong here
EFS is a versatile POSIX file system, but it is generally designed for content management and web serving. Even in Max I/O mode, it cannot match the specialized performance of FSx for Lustre or local Instance Store for high-performance computing workloads.
Quick reference
AWS S3 Storage Class Comparison
| Storage Class | Min Duration | Retrieval | Use Case |
|---|---|---|---|
| S3 Standard | None | Immediate | Frequently accessed data |
| S3 Standard-IA | 30 days | Immediate | Infrequent access, rapid retrieval |
| S3 One Zone-IA | 30 days | Immediate | Non-critical infrequent data |
| S3 Intelligent-Tiering | None | Immediate–hours | Unknown or changing access patterns |
| S3 Glacier Instant | 90 days | Milliseconds | Archive with instant retrieval |
| S3 Glacier Flexible | 90 days | Minutes–hours | Archive, flexible retrieval |
| S3 Glacier Deep Archive | 180 days | Hours | Long-term compliance archive |
About these practice questions
One of 149 original SAA-C03 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Amazon Web Services exam blueprint
This SAA-C03 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the SAA-C03 exam.