I've been having issues with slow IO on some of my containers, and I'm using AUFS. What is the cause of the slowdown with AUFS? Why do they not use Overlay2 as default if AUFS has such a major issue?
AUFS is the only fs that was broadly distributed until recently. Now, it's been removed in the latest linux distributions because it's too buggy and unstable.
Overlay was started and quickly abandoned. Only to be replaced by overlay2 that is work in progress and not wildly available yet.