AWS Certified SysOps Administrator – Associate (legacy) — Question 681

A company's data processing workflow uses AWS Lambda to interact with other AWS services, including AWS Step Functions, Amazon DynamoDB, and Amazon
S3. The Lambda functions make several API calls to these services as a part of the workflow. AWS CloudTrail has been enabled in the AWS Region and is logging to Amazon CloudWatch Logs. The Lambda functions are also logging to CloudWatch Logs.
A SysOps administrator notices that a specific Lambda function in the workflow is taking longer to run than it did last month. The SysOps administrator needs to determine the parts of the Lambda function that are experiencing higher-than-normal response times.
What solution will accomplish this?

Answer options

• A. Analyze logs in CloudWatch Logs for the timestamps at which the API calls are made while the Lambda function is running. Compare with the logs from the previous month.
• B. Enable AWS X-Ray for the function. Analyze the service map and traces to help identify the API calls with anomalous response times.
• C. Search CloudTrail logs for the calls from the Lambda function. Compare the observed and expected times of API calls relative to the time when the function starts.
• D. Use CloudWatch to monitor the Duration metric of function invocations for the Lambda function. Compare with the measurements from the previous month.

Correct answer: D

Explanation

Monitoring the Duration metric in Amazon CloudWatch provides direct visibility into the execution time of the Lambda function, allowing the administrator to compare current performance against historical data from the previous month. This metric helps confirm latency anomalies at the function level. Other options like CloudTrail or manual log analysis are less efficient for aggregate duration comparisons over time.