I just pushed a 2.8GB Docker image to the AWS container repository ECR. However, the Management Console gives the size of the image as 1.2GB. Why is that? I assume ECR comes with some automated compression, right?
There are two sizes reported for Docker images: compressed size and actual size on disk. The compressed file is what is sent over the network, so that is what image registries like ECR report, since it is how much bandwidth will be used to download the image.