- A
Use preemptible VMs to reduce cost during spikes
Why wrong: Preemptible VMs can be terminated at any time; the application is not fault-tolerant, so this would cause disruption.
- B
Configure pod disruption budgets to ensure a minimum number of pods remain available during node scaling
Pod disruption budgets protect against voluntary disruptions (e.g., node scaling), ensuring availability during spikes.
- C
Use Vertical Pod Autoscaler in Auto mode to automatically adjust pod resources without restarts
Why wrong: VPA in Auto mode can adjust resources but may require pod restarts; also, it's less responsive to sudden spikes than HPA.
- D
Configure cluster autoscaler to add nodes when utilization is high
Cluster autoscaler automatically adds nodes to handle increased load during spikes, then removes them when demand drops.
- E
Set cluster autoscaler scale-down delay to 0 for immediate cost savings
Why wrong: Setting scale-down delay to 0 may cause nodes to be removed too quickly, disrupting pods that are still processing requests.
PCDE Optimising Service Performance Practice Question
This PCDE practice question tests your understanding of optimising service performance. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 is migrating a stateful web application from on-premises to Google Kubernetes Engine (GKE). The application has variable traffic patterns, with occasional spikes. The team wants to optimize performance and availability while minimizing cost during spikes. The application is not fault-tolerant to instance restarts. Which TWO strategies should the team implement? (Choose TWO)
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
Configure pod disruption budgets to ensure a minimum number of pods remain available during node scaling
Cluster autoscaler adds nodes during spikes, but to avoid disruption from node scaling activities, pod disruption budgets should be configured to protect critical pods. Preemptible VMs are not suitable because the application is not fault-tolerant to restarts. VPA with Auto mode can adjust resource requests without restarting pods, but may take time to react to spikes; HPA is better for handling spikes quickly.
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.
- ✗
Use preemptible VMs to reduce cost during spikes
Why it's wrong here
Preemptible VMs can be terminated at any time; the application is not fault-tolerant, so this would cause disruption.
- ✓
Configure pod disruption budgets to ensure a minimum number of pods remain available during node scaling
Why this is correct
Pod disruption budgets protect against voluntary disruptions (e.g., node scaling), ensuring availability during spikes.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Use Vertical Pod Autoscaler in Auto mode to automatically adjust pod resources without restarts
Why it's wrong here
VPA in Auto mode can adjust resources but may require pod restarts; also, it's less responsive to sudden spikes than HPA.
- ✓
Configure cluster autoscaler to add nodes when utilization is high
Why this is correct
Cluster autoscaler automatically adds nodes to handle increased load during spikes, then removes them when demand drops.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Set cluster autoscaler scale-down delay to 0 for immediate cost savings
Why it's wrong here
Setting scale-down delay to 0 may cause nodes to be removed too quickly, disrupting pods that are still processing requests.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Detailed technical explanation
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- 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 PCDE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
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Optimising Service Performance — study guide chapter
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FAQ
Questions learners often ask
What does this PCDE question test?
Optimising Service Performance — This question tests Optimising Service Performance — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Configure pod disruption budgets to ensure a minimum number of pods remain available during node scaling — Cluster autoscaler adds nodes during spikes, but to avoid disruption from node scaling activities, pod disruption budgets should be configured to protect critical pods. Preemptible VMs are not suitable because the application is not fault-tolerant to restarts. VPA with Auto mode can adjust resource requests without restarting pods, but may take time to react to spikes; HPA is better for handling spikes quickly.
What should I do if I get this PCDE question wrong?
Identify which PCDE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
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Last reviewed: Jul 4, 2026
This PCDE practice question is part of Courseiva's free Google Cloud 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 PCDE exam.
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