- A
Switch to on-demand capacity mode.
On-demand mode instantly accommodates usage spikes without capacity planning. While typically more expensive for steady-state workloads, for unpredictable spikes it can be cost-effective because you don't pay for unused capacity. It eliminates throttling.
- B
Increase provisioned WCU to 2000 to cover the peak.
Why wrong: Paying for 2000 WCU at all times is wasteful because the average usage is likely much lower. This would increase costs significantly without a proportional benefit.
- C
Enable DynamoDB Auto Scaling with minimum 1000, maximum 2000 WCU.
Why wrong: Auto Scaling adjusts capacity based on utilization, but it can take several minutes to scale up. Sudden spikes may cause throttling before capacity increases. It also requires careful configuration and does not guarantee no throttling.
- D
Use a DynamoDB Accelerator (DAX) cache.
Why wrong: DAX is an in-memory cache that improves read performance, not write capacity. It does not help with write throttling or scaling of write capacity.
Quick Answer
The answer is to switch to DynamoDB on-demand capacity mode. This is correct because on-demand capacity instantly accommodates unpredictable spikes up to 2000 WCU without throttling, as it automatically scales to handle any traffic surge while you pay only for the actual reads and writes consumed. In contrast, provisioned capacity would require over-provisioning to 2000 WCU to avoid throttling, incurring fixed costs for rarely used peak capacity. On the AWS Certified SysOps Administrator Associate SOA-C02 exam, this scenario tests your understanding of when to choose on-demand over provisioned capacity, often appearing as a cost-optimization trap where candidates mistakenly consider Auto Scaling—but Auto Scaling still requires a baseline provisioned capacity and reacts slower than on-demand. A key memory tip: think “spiky and unpredictable = on-demand; steady and predictable = provisioned.”
SOA-C02 Cost and Performance Optimization Practice Question
This SOA-C02 practice question tests your understanding of cost and performance optimization. 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 company runs a production Amazon DynamoDB table with provisioned capacity of 1000 write capacity units (WCU). The table experiences unpredictable spikes up to 2000 WCU, causing throttling. The SysOps administrator wants to minimize cost while handling the spikes. Which solution should be used?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue:
"minimum / minimize"Why it matters: Asks for the least resource use — fewest addresses, smallest subnet, lowest overhead. Eliminate over-provisioned options even if they would technically work.
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
Switch to on-demand capacity mode.
Switching to on-demand capacity mode eliminates throttling during unpredictable spikes by automatically scaling write capacity up to the required 2000 WCU without any manual intervention or pre-provisioning. This minimizes cost because you pay only for the actual reads and writes consumed, avoiding the fixed cost of over-provisioning for peak capacity that may be rarely used.
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.
- ✓
Switch to on-demand capacity mode.
Why this is correct
On-demand mode instantly accommodates usage spikes without capacity planning. While typically more expensive for steady-state workloads, for unpredictable spikes it can be cost-effective because you don't pay for unused capacity. It eliminates throttling.
Clue confirmation
The clue word "minimum / minimize" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Increase provisioned WCU to 2000 to cover the peak.
Why it's wrong here
Paying for 2000 WCU at all times is wasteful because the average usage is likely much lower. This would increase costs significantly without a proportional benefit.
- ✗
Enable DynamoDB Auto Scaling with minimum 1000, maximum 2000 WCU.
Why it's wrong here
Auto Scaling adjusts capacity based on utilization, but it can take several minutes to scale up. Sudden spikes may cause throttling before capacity increases. It also requires careful configuration and does not guarantee no throttling.
- ✗
Use a DynamoDB Accelerator (DAX) cache.
Why it's wrong here
DAX is an in-memory cache that improves read performance, not write capacity. It does not help with write throttling or scaling of write capacity.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often choose DynamoDB Auto Scaling (Option C) thinking it handles spikes instantly, but they overlook the inherent scaling delay and the fact that it still requires a maximum capacity setting that may not cover sudden bursts, leading to throttling.
Detailed technical explanation
How to think about this question
DynamoDB on-demand capacity mode uses a traffic distribution algorithm that scales instantly to handle up to double the previous peak within 30 minutes, but for unpredictable spikes, it can absorb bursts without throttling because it provisions capacity based on actual usage patterns. Under the hood, on-demand tables have a baseline throughput and can burst to higher levels using a credit bucket system, but unlike provisioned mode, there is no hard limit that causes throttling during spikes. In real-world scenarios, workloads with infrequent but sharp spikes—such as flash sales or IoT event ingestion—benefit most from on-demand, as provisioned auto-scaling would require careful tuning of scaling policies to avoid throttling or over-provisioning.
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.
- →
Cost and Performance Optimization — study guide chapter
Learn the concepts, then practise the questions
- →
Cost and Performance Optimization practice questions
Targeted practice on this topic area only
- →
All SOA-C02 questions
1,546 questions across all exam domains
- →
AWS Certified SysOps Administrator Associate SOA-C02 study guide
Full concept coverage aligned to exam objectives
- →
SOA-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related SOA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Monitoring, Logging, and Remediation practice questions
Practise SOA-C02 questions linked to Monitoring, Logging, and Remediation.
Reliability and Business Continuity practice questions
Practise SOA-C02 questions linked to Reliability and Business Continuity.
Deployment, Provisioning, and Automation practice questions
Practise SOA-C02 questions linked to Deployment, Provisioning, and Automation.
Security and Compliance practice questions
Practise SOA-C02 questions linked to Security and Compliance.
Networking and Content Delivery practice questions
Practise SOA-C02 questions linked to Networking and Content Delivery.
Cost and Performance Optimization practice questions
Practise SOA-C02 questions linked to Cost and Performance Optimization.
SOA-C02 fundamentals practice questions
Practise SOA-C02 questions linked to SOA-C02 fundamentals.
SOA-C02 scenario practice questions
Practise SOA-C02 questions linked to SOA-C02 scenario.
SOA-C02 troubleshooting practice questions
Practise SOA-C02 questions linked to SOA-C02 troubleshooting.
Practice this exam
Start a free SOA-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 SOA-C02 question test?
Cost and Performance Optimization — This question tests Cost and Performance Optimization — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Switch to on-demand capacity mode. — Switching to on-demand capacity mode eliminates throttling during unpredictable spikes by automatically scaling write capacity up to the required 2000 WCU without any manual intervention or pre-provisioning. This minimizes cost because you pay only for the actual reads and writes consumed, avoiding the fixed cost of over-provisioning for peak capacity that may be rarely used.
What should I do if I get this SOA-C02 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "minimum / minimize". Asks for the least resource use — fewest addresses, smallest subnet, lowest overhead. Eliminate over-provisioned options even if they would technically work.
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 SOA-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 SOA-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.