Posted On: Jul 12, 2017

Auto Scaling now supports a new type of scaling policy called target tracking scaling policies that you can use to set up dynamic scaling for your application in just a few simple steps. Adding Auto Scaling to your application is one way to maximize the benefits of AWS. Auto Scaling helps you build systems that respond to changes in demand by automatically launching or terminating Amazon EC2 instances based on conditions that you define. This dynamic scaling helps to improve application availability and reduce costs. For example, you can use Auto Scaling to automatically launch EC2 instances for your Auto Scaling group when demand increases to help maintain performance, and terminate instances when demand drops to save money.

With target tracking, you select a load metric for your application, such as “Average CPU Utilization” or the new “Request Count Per Target” metric from Application Load Balancer, set the target value, and Auto Scaling adjusts the number of EC2 instances in your Auto Scaling group as needed to maintain that target. It acts like a home thermostat, automatically adjusting the system to keep the environment at your desired temperature. For example, you can configure target tracking to keep CPU utilization for your fleet of web servers at 50%. From there, Auto Scaling launches or terminates EC2 instances as required to keep the average CPU utilization at 50%.

Auto Scaling is available at no additional charge. Target tracking scaling policies are currently available for Amazon EC2 in all regions. You can also use target tracking scaling policies with Application Auto Scaling for Amazon DynamoDB today, and with Application Auto Scaling for other AWS services in the coming months.

You can get started with target tracking scaling policies for Auto Scaling using the AWS Management Console, AWS Command Line Interface (CLI), or AWS SDK.

To learn more, see the following resources:
AWS Blog
• The "Target Tracking Scaling" section of the Auto Scaling User Guide
• The "Application Load Balancer Metrics” section of the Application Load Balancer Guide
• The “Auto Scaling for DynamoDB” section of the Amazon DynamoDB Developer Guide

Target Tracking for Auto Scaling