> there are ten different backends to handle layering on Docker and that simple fact implies that none of them are good overlay2 is fast, it's in the mainline

> there are ten different backends to handle layering on Docker and that simple fact implies that none of them are good overlay2 is fast, it's in the mainline kernel, and it's now the default for new Docker installs. I expect all the devicemapper / aufs mess to be history soon.