DEA-C01 Data Ingestion and Transformation Practice Question
A company uses AWS Glue to transform data stored in S3. The Glue job runs daily and processes data in the range of hundreds of GB. The data engineer wants to optimize the job for cost and performance. Which THREE actions should be taken? (Choose THREE.)
⚠ Common exam trap
The trap here is that candidates mistakenly think reducing DPUs always saves cost, but AWS Glue bills by DPU-hour, so longer runtimes from fewer DPUs can actually increase cost, and the question explicitly asks for both cost and performance optimization.
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
✓
Increase the number of DPUs for the job
Increasing the number of DPUs (Data Processing Units) for an AWS Glue job can improve performance by enabling parallel processing of large datasets (hundreds of GB). AWS Glue allocates resources in increments of DPUs, where each DPU provides 4 vCPU and 16 GB of memory; scaling out DPUs reduces execution time, which can lower overall cost if the job runs fewer minutes, balancing cost and performance.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Store intermediate data in HDFS on Amazon EMR
Why it's wrong here
Adds complexity and cost without clear benefit.
- ✓
Increase the number of DPUs for the job
Why this is correct
More DPUs can reduce runtime, improving cost if job runs shorter.
- ✗
Reduce the number of DPUs to save cost
Why it's wrong here
Would increase runtime, potentially increasing cost.
- ✓
Use columnar data formats such as Parquet
Why this is correct
Improves performance and reduces data scanned.
- ✓
Partition the data by date or other high-cardinality columns
Why this is correct
Reduces the amount of data processed.
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 1,711 original DEA-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 →
Same concept, more angles
1 more way this is tested on DEA-C01
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A company uses AWS Glue to transform data in S3. The transformation job reads Parquet files, filters rows, and writes to another S3 bucket. The job takes longer than expected. Which change would MOST likely reduce the job execution time?
medium- A.Use a single large file instead of multiple small files.
- B.Reduce the number of partitions in the output data.
- C.Convert the input files from Parquet to CSV format.
- ✓ D.Increase the number of DPUs allocated to the Glue job.
Why D: Increasing the number of DPUs (Data Processing Units) allocated to the Glue job directly increases the parallelism of the Apache Spark-based execution environment. Since the job reads Parquet files, filters rows, and writes output, a bottleneck in compute capacity is the most likely cause of prolonged execution time. More DPUs allow Spark to distribute the workload across more executors, reducing overall runtime.
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DEA-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 DEA-C01 exam.