Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 807 discussion

eserved concurrency — It guarantees the maximum number of concurrent instances for the function which can be invoked. When a function has being with a reserved concurrency configuration then no other lambda function within the same AWS account and region can use that concurrency. There is no charge for configuring reserved concurrency for a function. Provisioned concurrency — This concurrency initializes a requested number of execution environments so that they are prepared to respond immediately to your function’s invocations. Note that configuring provisioned concurrency incurs charges to your AWS account.

Also Lambda provisioned concurrency incure additionnal Account charges (https://docs.aws.amazon.com/lambda/latest/dg/provisioned-concurrency.html), it's the best option because it is stated: - The company wants to reduce the compute costs and to maintain service latency for its customers. So maintaining service latency while reducing compute cost is requested. That being said, Lambda optimization is not a trivial task, that's why one should rely on AWS Compute Optimizer recommendations to analyze usage and find the best fit. Please read following for more insights: https://aws.amazon.com/blogs/compute/optimizing-aws-lambda-cost-and-performance-using-aws-compute-optimizer/

Increase the memory according to AWS Compute Optimizer recommendations --> so we can lower the duration of lambda function to reduce the cost. The ans must be between B & D

Provisioned Concurrency keeps the Lambda functions initialized and ready to process incoming events, reducing the cold start latency associated with spinning up new execution environments.

D is correct

When a large number of messages are in the SQS queue, Lambda scales out, adding additional functions to process the messages. The scale out can consume the concurrency quota in the account. To prevent this from happening, you can set reserved concurrency for individual Lambda functions. This ensures that the specified Lambda function can always scale to that much concurrency, but it also cannot exceed this number. https://docs.aws.amazon.com/lambda/latest/operatorguide/computing-power.html

When a large number of messages are in the SQS queue, Lambda scales out, adding additional functions to process the messages. The scale out can consume the concurrency quota in the account. To prevent this from happening, you can set reserved concurrency for individual Lambda functions. This ensures that the specified Lambda function can always scale to that much concurrency, but it also cannot exceed this number. https://docs.aws.amazon.com/lambda/latest/operatorguide/computing-power.html

To reduce compute costs and maintain service latency for customers while using AWS Lambda functions for processing CPU-intensive tasks, you can consider the following strategies: Optimize Lambda Function Configuration: Adjust the memory allocation for Lambda functions to better match the CPU requirements of your workload. Higher memory configurations provide more CPU power. Tune the timeout settings to match the expected processing time of your workload. This prevents unnecessary over-provisioning and reduces costs. Fine-tune the concurrency settings to control the number of concurrent executions based on your workload's characteristics. Use Provisioned Concurrency: AWS Lambda's provisioned concurrency feature allows you to preallocate a number of execution environments to handle incoming requests instantly. This can help reduce cold starts and maintain consistent performance, especially during peak events.

Reserved concurrency its no charges reduce the computation cost, "latency for its customer" then I'll go for A