Short Polling vs Long Polling
Short Polling and Long Polling are two methods that affect how the Consumer polls messages from an Amazon SQS queue. Short Polling is the default behavior, where the service returns immediately with up to the maximum number of messages requested if they are available. Messages may not necessarily be returned in the order they were sent, and empty responses might be returned if no messages are available when the request is made. Long Polling, on the other hand, allows the service to wait and return a response only when a message becomes available or the provided wait time has elapsed, reducing the number of empty responses and improving message processing efficiency. Long Polling saves costs by reducing the number of requests made, reducing the amount of resources consumed, and facilitating better scaling of the SQS service.
A Complete Guide: Short Polling vs Long Polling in Amazon SQS
Short Polling vs Long Polling:
The topic discusses the two types of message sampling methods in Amazon's Simple Queue Service (SQS): short polling and long polling. It’s crucial to comprehend these methods as an AWS Solution Architect as they greatly affect the system's efficiency and cost.
Short Polling:
Short Polling is a default method that Amazon SQS uses to return messages from a queue. However, the response of short polling might only contain a subset of the available messages due to the randomized sampling of a subset of the queue's servers.
Long Polling:
Contrarily, Long Polling is a method that does not return a response until a message is available in the queue, or the long poll times out. It helps in reducing the number of empty responses and thus minimizing cost.
Working:
With Short Polling, SQS samples a few servers (not all), and if no messages are found, it returns an empty response right away.
On the other hand, in Long Polling, SQS waits for messages to be available instead of immediately returning no messages.
Exam Tips:
When answering questions related to Short Polling vs Long Polling in an exam, remember:
1. Short Polling is the default method, provides quicker but potentially incomplete responses.
2. Long Polling is cost-effective as it reduces empty responses, but might have a delay as it waits for a message.
3. Short Polling might be preferable when promptness is more important than receiving all messages in a single request. Conversely, use Long Polling when it's crucial not to miss any messages and saving cost is a priority.
4. Understand how to enable long polling on a queue as it's not set up by default. You can set the 'Receive Message Wait Time' to a number greater than 0 to enable long polling.
AWS Certified Solutions Architect - Amazon SQS Example Questions
Test your knowledge of Amazon Simple Storage Service (S3)
Question 1
Your application experiences frequent fluctuations in the rate of incoming messages. Which Amazon SQS polling type would provide more predictable throughput?
Question 2
You are receiving a lot of empty responses while polling an Amazon SQS queue. Which type of polling should you consider switching to?
Question 3
Your company needs to process messages as fast as possible with the lowest latency. Which type of Amazon SQS polling should you implement?
Go Premium
AWS Certified Solutions Architect - Associate Preparation Package (2024)
- 2203 Superior-grade AWS Certified Solutions Architect - Associate practice questions.
- Accelerated Mastery: Deep dive into critical topics to fast-track your mastery.
- Unlock Effortless AWS Certified Solutions Architect preparation: 5 full exams.
- 100% Satisfaction Guaranteed: Full refund with no questions if unsatisfied.
- Bonus: If you upgrade now you get upgraded access to all courses
- Risk-Free Decision: Start with a 7-day free trial - get premium features at no cost!