Serverless & Lambda

Câu 1. A developer needs to run a short-lived data transformation function that executes for less than 10 seconds and is triggered by S3 object uploads. Which compute service is the MOST cost-effective?

Câu 2. A Lambda function processes API requests and experiences high latency on the first invocation after a period of inactivity. The function initializes a database connection pool during startup. How can the team reduce this cold start latency?

Câu 3. A Lambda function processes messages from an SQS queue. Occasionally, a message causes the function to fail repeatedly. The team wants to prevent the poison message from blocking the queue while preserving it for later analysis. What should they configure?

Câu 4. A company runs a Lambda function that processes 10 million invocations per month, each running for 200ms with 512 MB memory. The traffic pattern is unpredictable with bursts. Which approach optimizes cost while maintaining performance?

Câu 5. A Lambda function needs to process files up to 6 GB in size from S3. The function currently fails because the /tmp directory runs out of space. What is the recommended solution?

Câu 6. A company is building a REST API that will be consumed by a mobile application. The API needs request validation, throttling, and API key management. Which AWS service should they use?

Câu 7. A company has a REST API on API Gateway that receives thousands of identical GET requests per second for the same resource. The backend Lambda function returns the same response for a given request. How can they reduce Lambda invocations and improve response time?

Câu 8. A startup is building a simple CRUD API backed by Lambda functions. They need the lowest possible latency and cost, and do not require API key management or request validation. Which API Gateway type should they choose?

Câu 9. A company needs to orchestrate a multi-step order processing workflow that includes payment validation, inventory check, and shipping. If any step fails, the entire transaction must be rolled back. Which AWS service is best suited for this?

Câu 10. A data pipeline processes millions of small records daily using Step Functions. Each record requires a simple transformation Lambda invocation. The current Standard Workflow costs are high due to the per-state-transition pricing. How can the team reduce costs?

Câu 11. A Step Functions workflow needs to process 10,000 items from an S3 file in parallel, with each item processed by a Lambda function. The team wants to limit concurrency to 100 simultaneous Lambda invocations. Which Step Functions feature should they use?

Câu 12. A Lambda function behind API Gateway needs to return responses within 3 seconds. The function calls three independent downstream microservices, each taking 2 seconds. How should the developer optimize the function to meet the latency requirement?

Câu 13. A company wants to trigger a Step Functions workflow every day at 8:00 AM UTC to generate a daily report. The trigger must be fully serverless with no infrastructure to manage. Which solution should they use?

Câu 14. A company exposes a public API through API Gateway that is experiencing abuse from certain IP addresses causing high Lambda costs. They need to block specific IPs and rate-limit requests by source IP. What is the MOST effective solution?

Câu 15. A company wants to build a serverless web application with a React frontend and Lambda backend. They need to host the static frontend assets with low latency globally. What is the recommended architecture?

Câu 16. A Lambda function writes processed results to a DynamoDB table. The team wants to ensure that if the Lambda invocation is retried due to a transient error, duplicate records are not created in DynamoDB. How should they implement this?

Câu 17. A development team needs to coordinate a workflow where a Lambda function processes an image, then another Lambda function generates a thumbnail, and finally a third Lambda function updates a database. Which service provides visual workflow orchestration with built-in error handling?

Câu 18. A company has an API Gateway REST API that proxies requests to a backend running on EC2 instances. They want to reduce API Gateway costs while keeping the same functionality. What should they evaluate?

Câu 19. A microservices architecture uses EventBridge for inter-service communication. The team needs to ensure that events are delivered to the target even if the target service is temporarily unavailable. Which EventBridge feature provides this reliability?

Câu 20. A company uses Lambda functions extensively and notices that some functions have high memory allocation but low actual memory usage, while others run out of memory. They want to automatically right-size all Lambda functions. Which AWS tool should they use?