Google Cloud Professional Cloud Database Engineer — Question 40

Your team recently released a new version of a highly consumed application to accommodate additional user traffic. Shortly after the release, you received an alert from your production monitoring team that there is consistently high replication lag between your primary instance and the read replicas of your Cloud SQL for MySQL instances. You need to resolve the replication lag. What should you do?

Answer options

• A. Identify and optimize slow running queries, or set parallel replication flags.
• B. Stop all running queries, and re-create the replicas.
• C. Edit the primary instance to upgrade to a larger disk, and increase vCPU count.
• D. Edit the primary instance to add additional memory.

Correct answer: A

Explanation

The correct answer is A because optimizing slow queries can directly enhance the performance of the primary instance, reducing replication lag. Stopping all queries and recreating replicas (B) is a drastic measure that may not address the root cause of the lag. Upgrading disk size and vCPU count (C) or adding memory (D) may improve performance but do not specifically target the issues causing the replication lag.