Just as a quick note here, our Lambda function timeout has to be lower than the queue’s visibility timeout in order to create the event mapping from SQS to Lambda.
Standard queues provide at-least-once delivery, which means that each message is delivered at least once.
By grouping messages into batches, you can reduce your Amazon SQS costs.
Instead of trying to process failing messages until they expire, it is better to move them to a dead-letter queue after a few processing attempts.
Typical latencies for SendMessage, ReceiveMessage, and DeleteMessage API requests are in the tens or low hundreds of milliseconds.
Amazon SQS long polling results in higher performance at reduced cost in the majority of use cases.
The AmazonSQSBufferedAsyncClient for Java provides an implementation of the AmazonSQSAsyncClient interface and adds several important features: Prefetching of messages into a local buffer that allows your application to immediately process messages from Amazon SQS without waiting for the messages to be retrieved
This attribute specifies the limit on bytes that an Amazon SQS message can contain. Set this limit to a value between 1,024 bytes (1 KB), and 262,144 bytes (256 KB)
However, there is a 120,000 limit for the number of inflight messages for a standard queue
At-Least-Once Delivery – A message is delivered at least once, but occasionally more than one copy of a message is delivered.
For example, if the latency from an Amazon EC2-based client to Amazon SQS in the same region averages 20 ms, the maximum throughput from a single thread over a single connection averages 50 TPS.
For example, by default, instances of the AWS SDK for Java AmazonSQSClient class maintain at most 50 connections to Amazon SQS.
Batching performs more work during each round trip to the service (for example, when you send multiple messages with a single SendMessageBatch request).
Because ReceiveMessage can process 10 messages at a time, there is no ReceiveMessageBatch action.
Because each round trip carries more work, batch requests make more efficient use of threads and connections, improving throughput.
You can use batched Amazon SQS actions to send, receive, or delete up to 10 messages at a time. Because Amazon SQS charges by the request, batching can substantially reduce your costs.
delay queue allows the user to set a default delay on a queue such that delivery of all messages enqueued is postponed for that time duration
Each message receives a system-assigned message ID that SQS returns to with the SendMessage response.
Consumer should delete the message within the Visibility timeout. If the consumer fails to delete the message before the visibility timeout expires, the message is visible again for other consumers.
Pricing adds insult to the injury of performance in these services.
If we wanted to scale this application to 1 million messages a second,
the SQS request rate alone would cost $1,584 per hour. Note that this
does not account for the Lambda execution costs. T