I haven't used AUFS or overlay(fs), only devicemapper (thin provisioning) and Btrfs. Btrfs is faster than devicemapper, but even creating and removing container

I haven't used AUFS or overlay(fs), only devicemapper (thin provisioning) and Btrfs. Btrfs is faster than devicemapper, but even creating and removing containers seems slower than it ought to be considering how little delta there is. The create/remove time with 'btrfs sub crea/del' is much faster than docker create or remove (container), so I'm not really sure where the delays are.