- A
The DynamoDB table's read capacity units are underprovisioned, causing throttling.
Underprovisioned capacity throttles read/write requests, causing Lambda to retry, increasing execution time and potentially causing timeouts.
- B
The SQS queue's visibility timeout is too short, causing duplicate processing.
Why wrong: A short visibility timeout could cause duplicate messages but would not directly increase execution time; it could even decrease it as messages are reprocessed.
- C
The Lambda function's memory is too low, causing CPU throttling.
Why wrong: If memory were insufficient, the function would likely fail with out-of-memory errors, not consistently reach the 5-minute timeout.
- D
The DynamoDB table's indexes are missing, causing full table scans.
Why wrong: Missing indexes could increase query time, but full table scans are only done with Scan operations, not typical Get/Query patterns. Also, this would not appear suddenly without code or schema changes.
DVA-C02 Troubleshooting and Optimization Practice Question
This DVA-C02 practice question tests your understanding of troubleshooting and optimization. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. A key principle to apply: dynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput.. 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 developer monitors an AWS Lambda function that processes messages from an Amazon SQS queue. CloudWatch logs show that the function's execution time has increased significantly over the past week, and it now frequently times out at the 5-minute timeout. The function's code has not been changed recently. The function makes calls to an Amazon DynamoDB table. What is the most likely cause of the increased execution time?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"most likely"Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
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
The DynamoDB table's read capacity units are underprovisioned, causing throttling.
The most likely cause is that the DynamoDB table's read capacity units are underprovisioned, leading to throttling (ProvisionedThroughputExceededException). When DynamoDB throttles requests, the Lambda function must retry them, which adds latency and can cause the function to exceed its 5-minute timeout. Since the code hasn't changed, this points to a scaling or capacity issue on the DynamoDB side.
Key principle: DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
The DynamoDB table's read capacity units are underprovisioned, causing throttling.
Why this is correct
Underprovisioned capacity throttles read/write requests, causing Lambda to retry, increasing execution time and potentially causing timeouts.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput.
- ✗
The SQS queue's visibility timeout is too short, causing duplicate processing.
Why it's wrong here
A short visibility timeout could cause duplicate messages but would not directly increase execution time; it could even decrease it as messages are reprocessed.
- ✗
The Lambda function's memory is too low, causing CPU throttling.
Why it's wrong here
If memory were insufficient, the function would likely fail with out-of-memory errors, not consistently reach the 5-minute timeout.
- ✗
The DynamoDB table's indexes are missing, causing full table scans.
Why it's wrong here
Missing indexes could increase query time, but full table scans are only done with Scan operations, not typical Get/Query patterns. Also, this would not appear suddenly without code or schema changes.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates may confuse DynamoDB throttling with Lambda timeout configuration, overlooking that gradual performance degradation often points to downstream resource contention rather than function configuration.
Detailed technical explanation
How to think about this question
DynamoDB throttling occurs when read/write requests exceed the provisioned capacity, returning a 400 (ProvisionedThroughputExceededException). The AWS SDK for Lambda automatically retries throttled requests with exponential backoff, which can add seconds of delay per retry. If the function processes many items from the SQS batch, cumulative retries can easily push execution time past 5 minutes, especially if the table is shared with other workloads that increased traffic.
KKey Concepts to Remember
- DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput.
- Exceeding provisioned capacity in DynamoDB results in request throttling.
- Throttled requests require retries, increasing latency and execution time for dependent services.
- Underprovisioned capacity can manifest as sudden performance degradation without application code changes.
TExam Day Tips
- 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
DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput.
Real-world example
How this comes up in practice
A cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
What to study next
Got this wrong? Here's your next step.
Review dynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput., then practise related DVA-C02 questions on the same topic to reinforce the concept.
- →
Troubleshooting and Optimization — study guide chapter
Learn the concepts, then practise the questions
- →
Troubleshooting and Optimization practice questions
Targeted practice on this topic area only
- →
All DVA-C02 questions
1,616 questions across all exam domains
- →
AWS Certified Developer Associate DVA-C02 study guide
Full concept coverage aligned to exam objectives
- →
DVA-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related DVA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Development with AWS Services practice questions
Practise DVA-C02 questions linked to Development with AWS Services.
Security practice questions
Practise DVA-C02 questions linked to Security.
Deployment practice questions
Practise DVA-C02 questions linked to Deployment.
Troubleshooting and Optimization practice questions
Practise DVA-C02 questions linked to Troubleshooting and Optimization.
DVA-C02 fundamentals practice questions
Practise DVA-C02 questions linked to DVA-C02 fundamentals.
DVA-C02 scenario practice questions
Practise DVA-C02 questions linked to DVA-C02 scenario.
DVA-C02 troubleshooting practice questions
Practise DVA-C02 questions linked to DVA-C02 troubleshooting.
Practice this exam
Start a free DVA-C02 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this DVA-C02 question test?
Troubleshooting and Optimization — This question tests Troubleshooting and Optimization — DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput..
What is the correct answer to this question?
The correct answer is: The DynamoDB table's read capacity units are underprovisioned, causing throttling. — The most likely cause is that the DynamoDB table's read capacity units are underprovisioned, leading to throttling (ProvisionedThroughputExceededException). When DynamoDB throttles requests, the Lambda function must retry them, which adds latency and can cause the function to exceed its 5-minute timeout. Since the code hasn't changed, this points to a scaling or capacity issue on the DynamoDB side.
What should I do if I get this DVA-C02 question wrong?
Review dynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput., then practise related DVA-C02 questions on the same topic to reinforce the concept.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
DynamoDB uses Read Capacity Units (RCUs) and Write Capacity Units (WCUs) for throughput.
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 →
Keep practising
More DVA-C02 practice questions
- A developer is troubleshooting an AWS Lambda function that is triggered by an S3 event. The function occasionally fails…
- A developer needs to call AWS APIs from application code running on EC2. Which credential source should the AWS SDK use…
- A developer needs to allow an IAM user in a different AWS account to assume a role in the developer's account. The role…
- A developer needs to grant an IAM role in Account B read-only access to objects in an S3 bucket in Account A. The bucket…
- An API Gateway HTTP API should allow access only to users authenticated by an external OIDC provider. Which authorizer t…
- A developer needs to allow an EC2 instance to read from a DynamoDB table. Which is the best practice to grant permission…
Last reviewed: Jun 11, 2026
This DVA-C02 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 DVA-C02 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.