Recommended EC2 instance configurations for fast docker builds

We’re running docker builds on dedicated machines in our AWS cluster. What are the recommended instance configurations for maximizing docker build speed? I see here that Root volume type is relevant (ours is currently set to “Container default”) and here that a recommended instance is m5d.2xlarge? Any ideas / experience here? Seems like docker builds don’t speed up with additional CPU cores, but potentially would with additional network bandwidth + IO?