DP-300 Practice Question: Monitor, configure, and optimize database resources
You administer an Azure SQL Database that uses the General Purpose tier. Users report that queries are slow during peak hours. You need to identify if the slow performance is due to log write latency. Which metric should you examine in Azure Monitor?
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
✓
Log write latency
The correct metric to examine is Log write latency (option D), as it directly measures the time taken to write to the transaction log, which can indicate slow performance due to log write latency. Option A (Log IO percent) measures the percentage of log throughput used, not latency. Option B (Transaction log usage) measures log file space used, not performance. Option C (Average IO latency) includes both data and log I/O, so it is not specific to log writes.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Log IO percent
Why it's wrong here
Log IO percent measures the percentage of log throughput consumed against the provisioned limit, indicating log write saturation rather than latency. It is tempting because it is a log-specific metric, and it would be the right choice if the question asked whether the log write rate is approaching its throughput ceiling.
- ✗
Transaction log usage
Why it's wrong here
Transaction log usage reports the percentage of log space consumed, which reflects capacity rather than write latency. It is tempting because it is the only metric named for the transaction log, and it would be correct if the question asked whether the log is filling up or nearing its size limit.
- ✗
Average IO latency
Why it's wrong here
Average IO latency aggregates both data and log file I/O, so it cannot isolate log write latency. It is tempting because latency is exactly the symptom described, and it would be correct if the question asked for overall storage latency affecting the database rather than specifically the transaction log.
- ✓
Log write latency
Why this is correct
Log write latency directly measures the time taken to write transaction log records to durable storage, which is the precise bottleneck causing slow queries during peak hours in the General Purpose tier. Examining this metric in Azure Monitor isolates whether log throughput, not CPU or data I/O, constrains performance.
Go deeper
Related to this question
Learn chapter
Overview of Azure Data Platform Options
Key term
Azure SQL Performance Tuning
Azure SQL Performance Tuning is the process of optimizing the speed and efficiency of queries and database operations in Microsoft Azure SQL Database or SQL Managed Instance to reduce latency and improve throughput.
About these practice questions
This DP-300 question is part of Courseiva's 574-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DP-300 practice question is part of Courseiva's free Microsoft 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 DP-300 exam.