Google runs things internally as fat binaries inside cgroups, which is a Linux kernel feature that implements resource limits like "only give this thing 2GB of

Google runs things internally as fat binaries inside cgroups, which is a Linux kernel feature that implements resource limits like "only give this thing 2GB of memory" Docker combines cgroups with a layered filesystem and a tarfile to copy everything around in. It's the total package that is meaningful; the article argues against just one aspect and thus fails to cover the whole picture.