SNS

AWS SNS Throttling Limits

In Amazon Simple Notification Service (SNS), throttling refers to the restriction on the rate at which you can publish or deliver messages. Throttling limits ensure that the service operates efficiently and prevents excessive resource consumption, which could lead to outages or performance degradation.

SNS Throttling Limits Overview

Here are the primary throttling limits in AWS SNS:

1. Publish Rate (Message Publishing)

• The rate at which you can publish messages to SNS topics depends on your AWS account and the region you’re using.
• The default limit for publishing messages to SNS topics is:
  • 3000 messages per second per topic for standard SNS topics.
  • 10 messages per second per topic for FIFO SNS topics.
• Increase limit: If you need a higher rate, you can request a limit increase by contacting AWS Support.

2. Delivery Rate (Message Delivery)

• SNS sends messages to the endpoints (like SQS, Lambda, HTTPS, Email, etc.). The delivery rate can be throttled depending on the endpoint type:
  • SQS Endpoint: By default, SNS can send up to 30,000 messages per second to SQS queues.
  • HTTP/HTTPS Endpoint: SNS throttles HTTP/HTTPS deliveries to 10 requests per second by default (but this can be increased).
  • Lambda: The rate at which messages are sent to AWS Lambda functions is throttled to 1000 requests per second per AWS account.
  • Email and SMS: There are SMS sending limits and rate-limits for email through SES that may influence SNS message delivery.

3. Subscription Rate (Subscription Management)

• Adding/Removing Subscriptions: You can add or remove up to 50 subscriptions per second to/from a topic without hitting throttling limits.
• If you need to manage more subscriptions at a higher rate, you can request a limit increase from AWS.