MLS-C01 Practice Question: Machine Learning Implementation and Operations
A research lab is using SageMaker to train deep learning models on a custom dataset stored in S3. Each training job uses a single ml.p3.2xlarge instance. Recently, training jobs have been failing intermittently with 'NetworkError: Connection reset by peer' during the data download phase. The data scientist notices that the dataset is 50GB and the network throughput is low. The training script uses the default S3 download method (boto3) to copy data from S3 to the local instance storage. Which solution should the data scientist implement to resolve the issue?
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
✓
Use SageMaker Pipe mode to stream data directly from S3.
SageMaker Pipe mode streams training data directly from S3 without writing to local disk, avoiding the large download that causes network timeouts. Option A (mount EBS) does not eliminate the need to download 50GB, so it does not resolve the network reset. Option C (retry logic) may help but does not address the root cause of low throughput and large downloads. Option D (larger instance) increases bandwidth but does not guarantee connection stability and costs more.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Mount an EBS volume to the instance and copy data there before training.
Why it's wrong here
Still requires downloading; network issues persist.
- ✓
Use SageMaker Pipe mode to stream data directly from S3.
Why this is correct
Pipe mode avoids large local file downloads and is more resilient.
- ✗
Add retry logic in the training script to handle network errors.
Why it's wrong here
Retry logic may help but does not prevent the error; it could still fail repeatedly.
- ✗
Use a larger instance type like p3.8xlarge for better network bandwidth.
Why it's wrong here
Network errors can still occur; larger instances may not have proportionally more reliable connections.
Visual reference
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 |
Go deeper
Related to this question
About these practice questions
One of 1,672 original MLS-C01 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 by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
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.