Amazon Elastic Container Service (ECS) Cluster Auto Scaling is now available. With ECS Cluster Auto Scaling, your ECS clusters running on EC2 can automatically scale as needed to meet the resource demands of all tasks and services in your cluster, including scaling to and from zero. Managed scaling with ECS Cluster Auto Scaling improves the reliability, scalability, and cost of running containerized workloads on ECS.
ECS Cluster Auto Scaling uses the new ECS Capacity Provider construct in ECS, also launching today, to manage Amazon EC2 Auto Scaling Groups (ASG) on your behalf. Previously, ECS did not have the ability to directly manage the scaling of an ASG. Instead, you had to set up scaling policies on your ASG manually outside of ECS, and the metrics available for scaling did not account for the desired task count, only the tasks already running. With ECS Cluster Auto Scaling, the scaling policy of your ASG is managed by ECS through an ECS Capacity Provider. You can configure the Capacity Provider to enable managed scaling of the ASG, reserve excess capacity in the ASG, and also to manage termination of instances in the ASG.