I have run containers on bare metal and in Amazon. Performance can be noticeably slower in Amazon on machines with similar specifications. A detailed explanation why is in this informative video by Bryan Cantrill https://www.youtube.com/watch?v=coFIEH3vXPw. It is a talk about how layering containers on top of virtual machines is a recipe for poor performance and wasted resource utilization. He equates it to developers “being given fire, then proceeding to put the fire out.”