SQS

Question 1

____ is a web service that gives you access to message queues that can be used to store messages while waiting for a computer to process them.

Answer 1

SQS

Question 2

____ is a distributed queue system that enables web service apps to quickly and reliably queue messages that one component in the app generates to be consumed by another component.

Answer 2

SQS

Question 3

A _____ is a temp repo for messages that are awaiting processing.

Answer 3

queue

Question 4

Using _____, you can decouple the components of an app so they run independently, easing message management between components.

Answer 4

SQS

Question 5

Any component of a _____ app can store messages in the queue.

Answer 5

distributed

Question 6

Messages can contain up to ____kb of text in any format.

Answer 6

256kb

Question 7

Any component can later retrieve the messages programatically using the ___ ___.

Answer 7

SQS API

Question 8

The _____ acts as a buffer between the component producing and saving data, and the component resolving the data for processing.

Answer 8

queue

Question 9

The queue resolves issues that arise if the producer is producing work faster than the consumer can procesws it, or if the producer or consumer are only intermittently conencted to the network.

T or F

Answer 9

True

Question 10

SQS offers _____ as the default queue type.

Answer 10

standard.

Question 11

a ___ queue lets you have a nearly-unlimited number of transactions per second.

Answer 11

standard

Question 12

____ queues guarantee that a message is delivered at least once.

Answer 12

standard

Question 13

occasionally, (because of the highly distributed architecture that allows high throughput), more than one copy of a message might be delieverd out of order.

T or F

Answer 13

True

Question 14

___ queues provide best effort ordering which ensures that messages are generally delivered in the same order they are sent.

Answer 14

standard

Question 15

The ____ queue complements the standard queue.

Answer 15

FIFIO

Question 16

The most important features of this queue type are ____ delivery and exactly once processing: The order in which messages are sent and received is strictly preserved and a message is delivered once and remains available until a consumer processes and deletes it; duplicates are not introduced into the queue.

Answer 16

FIFO (first in first out)

Question 17

FIFO queues also support message groups that alloow ____ transactions per second (TPS), but have all the capabilities of standard queues.

Answer 17

300

Question 18

___ is pull based, not pushed based.

Answer 18

SQS

Question 19

SQS messagesa re ____kb in size

Answer 19

256

Question 20

sqs messages can be kept in the queue from ___ min to ___ days

Answer 20

1, 14

Question 21

SQS default retention period is ____ days

Answer 21

4

Question 22

____ guarantees your messages will be processed at least once.

Answer 22

SQS

Question 23

The ______ timeout is the amount of time that the message is invisible in the SQS queue after a reader picks up that message.

Answer 23

visibility

Question 24

Provided the job is processed before the visibility timeout expires, the message will then be ___ from the queue.

Answer 24

deleted

Question 25

If the job is not processed within that time, the message will become visible again and another _____will process it. This could result in the same message being delievered twice.

Answer 25

reader

Question 26

default visibility timeout is ____ seconds

Answer 26

30

Question 27

increase the visibility timeout if your task takes longer than ____ seconds

Answer 27

30

Question 28

max visibility timeout is ____ hours

Answer 28

12

Question 29

SQS ____ polling is a way to retrieve messages from your SQS queues

Answer 29

long

Question 30

While the regular ____ polling returns immediately (even if the message queue being polled is empty), long polling doesn’t return a response until a message arrives in the message queue, or the long poll times out.

as such, long polling can save you money.

Answer 30

short

Question 31

____ allows you to decouple the components of an app, so that they are independent

Answer 31

SQS

Question 32

SQS ____ queues - postpone delivery of new messages

Answer 32

delay

Question 33

messages sent to the _____ queue remain invissible to consumers for the duration of the delay period

Answer 33

delay

Question 34

default delay is ___seconds, max is ____

Answer 34

0, 900

Question 35

T or F

for standard SQS queues, changing the settings to postpone the dellivery of new messages doesn’t affect the delay of the messages already in the queue, only new messages

Answer 35

T

Question 36

for FIFO queues, changing the setting to postpone the delivery of new messages affects the delay of messages already in teh queue

Answer 36

yes

Question 37

what should you use delay queue?

Answer 37

• large distributed apps which may need to introduce a delay in processing
• you need to apply a delay to an entire queue of messages
• adding a delay of a few seconds, to allow for updates to your sales and stock control databases before sending a notification to a customer confirming an online transaction

Question 38

Best practices for managing large SQS messages using S3

• for large SQ messages - ___kb - ___GB in size
• uses ___ to store the messages
• use amazon SQ ___ ___ ____ ___ ___ to manage them
• you’ll also need the aws ___ for java - provides an API for S3 bucket and object operations

Answer 38

256kb-2gb

s3

extended client library for java

sdk

Question 39

SQS extended client library for java allows you to:

• specify that messages are always stored in s3 or only messages > 256kb
• send a message which references a message object stored in s3
• get a message object from s3
• delete a message object from s3

Answer 39

yes

Question 40

sqs delay queues and managing large messages

cannot use:

aws cli, aws management console, sqs console, sqs api

Answer 40

yes