When a Simple Queue Service message triggers a task that takes 5 minutes to complete,
which process below will result in successful processing of the message and remove it from
the queue while minimizing the chances of duplicate processing?
A.
Retrieve the message with an increased visibility timeout, delete the message from the
queue, process the message
B.
Retrieve the message with increased DelaySeconds, process the message, delete the
message from the queue
C.
Retrieve the message with an increased visibility timeout, process the message, delete
the message from the queue
D.
Retrieve the message with increased DelaySeconds, delete the message from the
queue, process the message
C
C
Answer = C
http://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-delay-queues.html
Delay queues are similar to visibility timeouts because both features make messages unavailable to consumers for a specific period of time. The difference between delay queues and visibility timeouts is that for delay queues a message is hidden when it’s first added to queue, whereas for visibility timeouts a message is hidden only after a message is retrieved from the queue. The following figure illustrates the relationship between delay queues and visibility timeouts.
C
Right Answer is C
Delay queues are similar to visibility timeouts because both features make messages unavailable to consumers for a specific period of time. The difference between delay queues and visibility timeouts is that for delay queues a message is hidden when it’s first added to queue, whereas for visibility timeouts a message is hidden only after a message is retrieved from the queue. The following figure illustrates the relationship between delay queues and visibility timeouts.
http://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-delay-queues.html