Which action should be taken?
Configure a dead-letter queue to retry any throttled executions
Modify the memory settings on the Lambda function to allow for 500 parallel executions
Move the image-processing logic to AWS Step Functions
Set the reserved concurrency for the image-processing Lambda function to 500
Explanations:
A dead-letter queue (DLQ) is used for capturing failed invocations, not for handling throttling. It does not help ensure capacity for 500 parallel executions.
Modifying the memory settings can affect the performance and cost of individual Lambda executions, but it does not ensure that 500 simultaneous executions will be allowed. Lambda concurrency is not tied to memory settings.
AWS Step Functions are useful for orchestrating multiple Lambda functions and workflows, but they don’t inherently guarantee sufficient parallelism for Lambda executions. This option doesn’t directly solve the concurrency issue.
Setting reserved concurrency ensures that a fixed amount of Lambda capacity (in this case, 500) is always available for the image-processing function, regardless of other workloads. This directly addresses the administrator’s task.
I measure that the answer is:
Set the reserved concurrency for the image-processing Lambda function to 500