The answer is to mount an Amazon FSx for Lustre file system linked to the S3 bucket. This is correct because FSx for Lustre acts as a high-performance, POSIX-compliant file system that transparently caches S3 training data locally on the GPU instance, eliminating I/O bottlenecks by providing sub-millisecond latencies and high throughput directly to the compute layer. On the AWS Certified Machine Learning Specialty MLS-C01 exam, this scenario tests your understanding of optimizing data ingestion for deep learning workloads, where S3’s native latency can stall GPU utilization. A common trap is choosing Instance Store, which is ephemeral and lost on stop, or EBS io2, which offers high IOPS but lacks native S3 caching and requires manual data copying. Remember the key: FSx for Lustre is purpose-built for “cache S3 training data locally for SageMaker” by linking directly to the bucket, making it the only option that combines persistence, speed, and seamless S3 integration. Memory tip: “Lustre links to S3—no copy, no stop.”
MLS-C01 Data Engineering Practice Question
This MLS-C01 practice question tests your understanding of data engineering. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A data scientist is training a deep learning model on a GPU instance. The training data is stored in S3 and is 50 GB. To reduce I/O bottlenecks, which storage option should be used to cache the data locally on the instance?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Mount an Amazon FSx for Lustre file system linked to the S3 bucket
Option A is correct because Amazon FSx for Lustre provides a high-performance file system integrated with S3 that can cache data locally. Option B is wrong because EBS with io2 volumes offers high IOPS but is not optimized for S3 caching; Option C is wrong because EFS is a shared file system with lower throughput; Option D is wrong because Instance Store is ephemeral and not persistent.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Attach an Amazon EFS file system to the instance and copy data from S3
Why it's wrong here
EFS is not designed for high-throughput caching of S3 data.
✓
Mount an Amazon FSx for Lustre file system linked to the S3 bucket
Why this is correct
FSx for Lustre provides high throughput and can cache S3 data locally.
Related concept
Read the scenario before looking for a memorised answer.
✗
Provision an Amazon EBS io2 volume and copy data from S3 using AWS DataSync
Why it's wrong here
This adds latency and complexity; not the best for caching.
✗
Use instance store volumes to cache the data from S3
Why it's wrong here
Instance store is ephemeral and not reliable for caching.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
Use explanations to understand the rule behind the answer.
TExam Day Tips
→Underline the problem statement mentally.
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
What to study next
Got this wrong? Here's your next step.
Identify which MLS-C01 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
Data Engineering — This question tests Data Engineering — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Mount an Amazon FSx for Lustre file system linked to the S3 bucket — Option A is correct because Amazon FSx for Lustre provides a high-performance file system integrated with S3 that can cache data locally. Option B is wrong because EBS with io2 volumes offers high IOPS but is not optimized for S3 caching; Option C is wrong because EFS is a shared file system with lower throughput; Option D is wrong because Instance Store is ephemeral and not persistent.
What should I do if I get this MLS-C01 question wrong?
Identify which MLS-C01 exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This MLS-C01 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 MLS-C01 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.