Google Cloud Professional Cloud Developer — Question 282

You maintain a popular mobile game deployed on Google Cloud services that include Firebase, Firestore, and Cloud Functions. Recently, the game experienced a surge in usage, and the application encountered HTTP 429 RESOURCE_EXHAUSTED errors when accessing the Firestore API. The application has now stabilized. You want to quickly fix this issue because your company has a marketing campaign next week and you expect another surge in usage. What should you do?

Answer options

• A. Request a quota increase, and modify the application code to retry the Firestore API call with fixed backoff.
• B. Request a quota increase, and modify the application code to retry the Firestore API call with exponential backoff.
• C. Optimize database queries to reduce read/write operations, and modify the application code to retry the Firestore API call with fixed backoff.
• D. Optimize database queries to reduce read/write operations, and modify the application code to retry the Firestore API call with exponential backoff.

Correct answer: D

Explanation

Option D is correct because optimizing database queries can help reduce the load on Firestore, while using exponential backoff for retries is more effective in handling transient errors like RESOURCE_EXHAUSTED. Options A and C do not utilize exponential backoff, which is essential for efficiently managing retries during high-traffic situations. Option B lacks the optimization of database queries, which is crucial for preventing future quota issues.