When a Lambda function processes messages from an SQS queue but fails to handle certain messages properly, the same messages may be returned to the queue and retried repeatedly. In some cases, especially if the Lambda is also writing messages back to the same or a chained queue, this can create a recursive invocation loop. This loop results in high invocation counts, prolonged execution, and unnecessary costs, particularly if retries continue without a termination strategy.
Billed based on the number of invocations and duration of execution time in milliseconds, rounded up to the nearest 1ms. Repeated or unintended invocations directly increase cost.
