Intro

• Used to asynchronously decouple applications
• Supports multiple producers & consumers
• The consumer polls the queue for messages. Once a consumer processes a message, it deletes it from the queue using DeleteMessage API.
• Unlimited number of messages in queue
• Max 10 messages received per batch (configured using MaxNumberOfMessages parameter in the ReceiveMessage API)
• Max message size: 256 KB
• Default message retention: 4 days (max: 14 days)
• Consumers could be EC2 instances or Lambda functions
• Queue type cannot be changed once created

<aside> 💡 SQS cannot ingest data, it must be sent to the queue by the producer (use KDS or KDF instead)

</aside>

Queue Types

Standard Queue

• Unlimited throughput (publish any number of message per second into the queue)
• Low latency (<10 ms on publish and receive)
• Can have duplicate messages (at least once delivery)
• Can have out of order messages (best effort ordering)

FIFO Queue