AWS Certified Developer – Associate (DVA-C02) — Question 243

A company deploys a photo-processing application to an Amazon EC2 instance. The application needs to process each photo in less than 5 seconds. If processing takes longer than 5 seconds, the company’s development team must receive a notification.

How can a developer implement the required time measurement and notification with the LEAST operational overhead?

Answer options

• A. Create an Amazon CloudWatch custom metric. Each time a photo is processed, publish the processing time as a metric value. Create a CloudWatch alarm that is based on a static threshold of 5 seconds. Notify the development team by using an Amazon Simple Notification Service (Amazon SNS) topic.
• B. Create an Amazon Simple Queue Service (Amazon SQS) queue. Each time a photo is processed, publish the processing time to the queue. Create an application to consume from the queue and to determine whether any values are more than 5 seconds. Notify the development team by using an Amazon Simple Notification Service (Amazon SNS) topic.
• C. Create an Amazon CloudWatch custom metric. Each time a photo is processed, publish the processing time as a metric value. Create a CloudWatch alarm that enters ALARM state if the average of values is greater than 5 seconds. Notify the development team by sending an Amazon Simple Email Service (Amazon SES) message.
• D. Create an Amazon Kinesis data stream. Each time a photo is processed, publish the processing time to the data stream. Create an Amazon CloudWatch alarm that enters ALARM state if any values are more than 5 seconds. Notify the development team by using an Amazon Simple Notification Service (Amazon SNS) topic.

Correct answer: A

Explanation

Option A is correct because it directly publishes the processing time as a CloudWatch metric and uses a simple alarm to notify the development team when the threshold is crossed, minimizing operational overhead. Options B and D introduce unnecessary complexity with SQS and Kinesis, respectively, which require additional infrastructure and management. Option C uses an average metric instead of individual processing times, which may not accurately reflect the requirement for immediate notifications.