- A
Increase the batch size to 100.
Since the function can handle more messages per invocation, increasing the batch size reduces the number of invocations, which reduces throttling and increases throughput without changing reserved concurrency.
- B
Increase reserved concurrency to 10.
Why wrong: Increasing reserved concurrency would reduce throttling but directly contradicts the requirement to not increase reserved concurrency.
- C
Change the function timeout to 15 minutes.
Why wrong: Increasing timeout does not reduce the number of invocations or throttling. The function may still be throttled due to concurrency limits.
- D
Enable SQS short polling to reduce latency.
Why wrong: Short polling returns results immediately if messages are available, but it does not affect the number of invocations or throttling. It may even increase the number of empty responses.
DVA-C02 Troubleshooting and Optimization Practice Question
This DVA-C02 practice question tests your understanding of troubleshooting and optimization. Examine the command output carefully: the correct answer depends on what the output actually shows, not on general recall alone. 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 developer notices that an AWS Lambda function, which processes messages from an SQS queue, is taking longer than expected. The function has a reserved concurrency of 5 and a batch size of 10. The SQS queue has a large backlog. CloudWatch metrics show that the function's throttles are high. The function is idempotent and can process up to 100 messages per invocation. What is the most effective way to increase throughput without increasing reserved concurrency?
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 batch size to 100.
Increasing the batch size to 100 allows each invocation to process up to 100 messages instead of 10, directly increasing throughput per invocation without changing the reserved concurrency of 5. Since the function is idempotent and can handle up to 100 messages per invocation, this change maximizes the number of messages processed per Lambda execution, reducing the backlog more efficiently.
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.
- ✓
Increase the batch size to 100.
Why this is correct
Since the function can handle more messages per invocation, increasing the batch size reduces the number of invocations, which reduces throttling and increases throughput without changing reserved concurrency.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Increase reserved concurrency to 10.
Why it's wrong here
Increasing reserved concurrency would reduce throttling but directly contradicts the requirement to not increase reserved concurrency.
- ✗
Change the function timeout to 15 minutes.
Why it's wrong here
Increasing timeout does not reduce the number of invocations or throttling. The function may still be throttled due to concurrency limits.
- ✗
Enable SQS short polling to reduce latency.
Why it's wrong here
Short polling returns results immediately if messages are available, but it does not affect the number of invocations or throttling. It may even increase the number of empty responses.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates may assume increasing batch size is always beneficial, but in reality, AWS Lambda's maximum batch size for SQS is 10, so the option to increase to 100 is unrealistic and tests whether you recognize the constraint or focus on the conceptual improvement.
Detailed technical explanation
How to think about this question
Lambda integrates with SQS via event source mapping, which polls the queue and invokes the function with a batch of messages. The batch size determines how many messages are sent in a single event payload; increasing it to the maximum of 10 (for standard queues) or 10,000 (for FIFO queues) can significantly improve throughput. However, note that for standard queues, the maximum batch size is 10, so the option to increase to 100 is technically incorrect in a real-world scenario—this is a common exam trick where the question assumes a higher limit for the sake of testing understanding of batch processing.
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.
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
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 startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
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 — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Increase the batch size to 100. — Increasing the batch size to 100 allows each invocation to process up to 100 messages instead of 10, directly increasing throughput per invocation without changing the reserved concurrency of 5. Since the function is idempotent and can handle up to 100 messages per invocation, this change maximizes the number of messages processed per Lambda execution, reducing the backlog more efficiently.
What should I do if I get this DVA-C02 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
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.