AWS DevOps Engineer Professional Practice Test

For optimizing Lambda function performance, what setting should you monitor?

1. Memory allocated

2. Storage used

3. Execution role policies

4. Scheduled events

The correct answer is: Memory allocated

Monitoring the memory allocated to a Lambda function is crucial for optimizing its performance. AWS Lambda allows you to allocate memory to your function, ranging from 128 MB to 10,240 MB. This setting directly impacts both the function’s performance and the cost associated with running it. When you increase the memory allocated to a Lambda function, you indirectly increase the CPU power allocated to the function as well, since CPU allocation is proportional to the amount of memory specified. Therefore, if a function is CPU-bound or experiencing latency issues, increasing the memory may result in improved execution times and overall performance. Moreover, Lambda has a billing model based on the amount of memory allocated and the time it takes to execute the function. If a function consumes less memory than allocated, it may lead to unnecessary costs. Thus, balancing performance with efficient memory usage is critical for cost optimization. Other options do not have the same direct impact on the performance of the Lambda function. For instance, while storage used could be relevant in some contexts, it does not directly influence the execution speed or performance of the Lambda function. Execution role policies mainly govern permissions and access control, rather than performance. Scheduled events are related to how and when the function is triggered, but they do not affect the function