PCDOE Optimizing service performance Practice Question
This PCDOE practice question tests your understanding of optimizing service performance. 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 serves static content using a global HTTP(S) load balancer with Cloud CDN. They want to maximize the cache hit ratio. Which two actions should they take?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Set Cache-Control: public, max-age=31536000.
Setting Cache-Control: public, max-age=31536000 instructs browsers and intermediate caches to store the response for one year, maximizing the likelihood that subsequent requests are served from cache. This long max-age reduces the need for revalidation, directly improving cache hit ratio.
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 signed URLs for all requests.
Why it's wrong here
Signed URLs are for access control, not caching; they may reduce cacheability.
✓
Set Cache-Control: public, max-age=31536000.
Why this is correct
A long max-age allows content to be cached for a year, maximizing cache hits.
Related concept
Read the scenario before looking for a memorised answer.
✓
Enable Cloud CDN with cache key based on URL and host.
Why this is correct
Cloud CDN caches content based on the cache key; using URL and host is standard for static content.
Related concept
Read the scenario before looking for a memorised answer.
✗
Set Cache-Control: private.
Why it's wrong here
Private cache control prevents shared caches like CDN from storing the content.
✗
Enable Identity-Aware Proxy (IAP) for the backend.
Why it's wrong here
IAP requires authentication, which makes content uncacheable by CDN.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Google Cloud often tests the misconception that signed URLs or IAP improve caching, when in fact they introduce per-request variability that reduces cache hit ratio, and that Cache-Control: private is appropriate for static content when it actually prevents caching entirely.
Detailed technical explanation
How to think about this question
Cloud CDN respects the Cache-Control header from the origin; a max-age of 31536000 seconds (1 year) is the maximum allowed by RFC 7234, and combined with a cache key based on URL and host ensures that identical requests from different users hit the same cached object. In practice, this is ideal for immutable static assets like versioned JavaScript or images, where the content never changes and revalidation is unnecessary.
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 company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
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.
Optimizing service performance — This question tests Optimizing service performance — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Set Cache-Control: public, max-age=31536000. — Setting Cache-Control: public, max-age=31536000 instructs browsers and intermediate caches to store the response for one year, maximizing the likelihood that subsequent requests are served from cache. This long max-age reduces the need for revalidation, directly improving cache hit ratio.
What should I do if I get this PCDOE 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 →
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.
This PCDOE 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 PCDOE 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.