before embarking on major changes, to be safe, seems to make sense to snapshot the (root) partition first. but snapshots were designed to be quickly deleted, at the expense of inefficient writes meanwhile. if i want to keep the snapshot for awhile, i want to reverse that tradeoff, ie iiuc it will be far more efficient to make changes in the snapshot rather than in the origin. and to save a reboot, it might be nice to just pivot_root into the snapshot, though by the time one restarts services et al the reboot would be simpler. does this make sense? is there a better way? next3 looks promising except that i don't see it surfacing in 'official' channels tia, -g