- A
pubsub.googleapis.com/subscription/oldest_unacked_message_age
This metric directly shows the age of the oldest unacknowledged message, indicating processing latency.
- B
pubsub.googleapis.com/subscription/num_undelivered_messages
Why wrong: This metric gives the count of undelivered messages, not their age.
- C
pubsub.googleapis.com/topic/send_request_count
Why wrong: This is a topic metric for publish requests, not subscription latency.
- D
pubsub.googleapis.com/topic/publish_latency
Why wrong: This measures the time to publish messages, not the age of unacked messages.
Question 476 of 1,000
PDE Maintaining and Automating Data Workloads Practice Question
This PDE practice question tests your understanding of maintaining and automating data workloads. 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.
You want to monitor the latency of messages in a Pub/Sub subscription. Which Cloud Monitoring metric should you use to see the age of the oldest unacknowledged message?
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
✓
pubsub.googleapis.com/subscription/oldest_unacked_message_age
The metric 'subscription/oldest_unacked_message_age' measures the age (in seconds) of the oldest unacknowledged message in a subscription. This helps track processing lag. The other metrics measure different aspects: num_undelivered_messages is count, not age; topic metrics are irrelevant for subscription lag; publish_latency is about publishing, not consumption.
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.
- ✓
pubsub.googleapis.com/subscription/oldest_unacked_message_age
Why this is correct
This metric directly shows the age of the oldest unacknowledged message, indicating processing latency.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
pubsub.googleapis.com/subscription/num_undelivered_messages
Why it's wrong here
This metric gives the count of undelivered messages, not their age.
- ✗
pubsub.googleapis.com/topic/send_request_count
Why it's wrong here
This is a topic metric for publish requests, not subscription latency.
- ✗
pubsub.googleapis.com/topic/publish_latency
Why it's wrong here
This measures the time to publish messages, not the age of unacked messages.
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 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. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. 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.
Identify which PDE 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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Maintaining and Automating Data Workloads — study guide chapter
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FAQ
Questions learners often ask
What does this PDE question test?
Maintaining and Automating Data Workloads — This question tests Maintaining and Automating Data Workloads — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: pubsub.googleapis.com/subscription/oldest_unacked_message_age — The metric 'subscription/oldest_unacked_message_age' measures the age (in seconds) of the oldest unacknowledged message in a subscription. This helps track processing lag. The other metrics measure different aspects: num_undelivered_messages is count, not age; topic metrics are irrelevant for subscription lag; publish_latency is about publishing, not consumption.
What should I do if I get this PDE question wrong?
Identify which PDE 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 PDE 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 PDE exam.
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