In AWS SQS, what functionality does long polling provide?

Long polling in AWS Simple Queue Service (SQS) is designed to enhance the way message retrieval operates. When a receive message call is made using long polling, the request can wait for a specified duration (up to 20 seconds) for messages to become available in the queue before returning a response. This contrasts with short polling, where the call returns immediately, regardless of whether messages are present.

The advantage of long polling is that it reduces the number of empty responses and unnecessary API requests when the queue is empty. This functionality not only improves efficiency but also leads to lower costs since you avoid the charges associated with multiple requests when a queue happens to be empty. By waiting until messages are available before responding, long polling provides a more effective solution for ensuring that messages are processed promptly without overwhelming the system with calls when there are no messages to retrieve.

The other options do not align with long polling functionalities. Immediate message delivery implies a continuous flow of messages, which is not a characteristic of long polling; it rather waits for messages. Faster message processing is not guaranteed through long polling alone; it simply changes the timing of when a call is made. Lastly, reduction in message size isn’t related to the polling mechanism, as long polling does not affect