Application Services Flashcards
Is SQS pull-based or push-based?
Pull-based
What’s the maximum size of an SQS message?
256Kb
How much time does a message can be kept in a queue in SQS?
From 1 minute to 14 days (4 days by default)
What’s the visibility timeout in SQS?
Visibility timeout is the amount of time that the message is invisible in the SQS queue after a reader picks up that message. If the job is not processed within that time, the message will become visible again and another reader will process it. This could result in the same message being delivered twice.
What does SQS guaranty?
SQS guarantees that your message will be processed at least once.
What does the WaitTimeSeconds attribute mean in SQS?
WaitTimeSeconds = 0 => Short polling
When the consumer instance polls for new work, the SQS service will allow waiting a certain time for one or more messages to be available before closing the connection.
By default, Amazon SQS uses short polling. Short polling occurs when the WaitTimeSeconds parameter of a ReceiveMessage request is set to 0.
What is the maximum “VisibiltyTimeout” of an SQS message in a FIFO queue?
12 hours (do not confuse it with how the message can remain in the queue, which is 14 days)
In SWF, what does a “domain” refer to?
A collection of related workflows
Auditing user access/API calls etc across the entire AWS estate can be achieved by using ________.
CloudTrail
Amazon SWF ensures that a task is assigned only once and is never duplicated. True or False.
True
What does Amazon SES stand for?
Simple Email Service
What does Amazon SWF stand for?
Simple Work Flow
SWF actors
Starters, Deciders and Workers
Kinesis services
Streams
Firehose
Analytics
Kinesis Streams terminology
Shards, Consumers, Data retention…
