A Debian Virtual machine runs as a Guest VirtualBox VM. It's filesystem is EXT3. The host system loses power and after booting up the host system and guest VM, I find that the VM's filesystem has been rolled back to a previous state, losing changes made to the filesystem some time before losing power. The operations that were rolled back had been fully completed before the loss of power (files fully copied, file handles closed, etc.), but it's possible and even likely that other write operations were occuring on the VM at the point of the crash.

So I am trying to figure out if it's the filesystem recovery process that rolls back filesystem operations after encountering corruption post power loss, or is it possibly related to VirtualBox and the way it ignores flush requests for performance gains by default (discussed here)

Are there any other factors that would result in the filesystem being rolled back after losing power?