Exam AWS Certified Developer - Associate DVA-C02 topic 1 question 290 discussion

Resources: HighPriorityEventSourceMapping: Type: AWS::Lambda::EventSourceMapping Properties: BatchSize: 10 MaximumConcurrency: 10 EventSourceArn: arn:aws:sqs:region:account-id:high-priority-queue FunctionName: myLambdaFunction LowPriorityEventSourceMapping: Type: AWS::Lambda::EventSourceMapping Properties: BatchSize: 10 MaximumConcurrency: 90 EventSourceArn: arn:aws:sqs:region:account-id:low-priority-queue FunctionName: myLambdaFunction

You can use the maximum concurrency setting to control scaling behavior for your SQS event sources. The maximum concurrency setting limits the number of concurrent instances of the function that an Amazon SQS event source can invoke. Maximum concurrency is an event source-level setting. If you have multiple Amazon SQS event sources mapped to one function, each event source can have a separate maximum concurrency setting. You can use maximum concurrency to prevent one queue from using all of the function's reserved concurrency or the rest of the account's concurrency quota. There is no charge for configuring maximum concurrency on an Amazon SQS event source.

C is the correct answer.

https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html#events-sqs-max-concurrency

Should be C

None of them seems to be guarantee the requirement. Set the reserved concurrency on the Lambda function to 100 to limit the total invocations across all triggers. Configure the event source mapping for the high priority queue to use a maximum concurrency that ensures its messages are processed first. This could be most of the reserved concurrency (but not all, to allow for some processing of the low priority queue). Configure the event source mapping for the low priority queue with a smaller maximum concurrency to ensure it doesn't starve the high priority queue of Lambda resources.