Amazon EC2 Container Service (Amazon ECS) can now automatically scale container-based applications by dynamically growing and shrinking the number of tasks run by an Amazon ECS service.
Now, you can automatically scale an Amazon ECS service based on any Amazon CloudWatch metric. For example, you can use CloudWatch metrics published by Amazon ECS, such as each service’s average CPU and memory usage. You can also use CloudWatch metrics published by other services or use custom metrics that are specific to your application. For example, a web service could increase the number of tasks based on Elastic Load Balancing metrics like SurgeQueueLength, while a batch job could increase the number of tasks based on Amazon SQS metrics like ApproximateNumberOfMessagesVisible.