The 05/07/11, Eric Blake wrote: > I was trying to model this after the virDomainSnapshot API, which has a > notion of current snapshot, but I guess I don't fully understand what > that API was implying by current domain snapshot. > > After looking more through the code, it looks like the idea was to > support the notion of a branching hierarchy of snapshots: > > A -> B -> D > \-> C -> E > > such that you can revert to the snapshot at point B, start the domain, > and create snapshot D; then stop the domain, revert to the snapshot at > point C, start the domain, and create snapshot E. Every time you start > the domain, you know from which state it was started, so the current > snapshot is the snapshot that would be the parent if you were to create > a snapshot right now. > > As long as you can create a branching hierarchy (that is, after creating > a snapshot, you can revert to its parent state, then make different > changes, and create a new snapshot), then there really is a need to know > which snapshot is current - listing all snapshots can show you the > parent(s) of each snapshot in that list, but can't tell you which > snapshot would be the parent of a new one created right now. May I ask what would happen if the user asks for deletion of A (as both base and snapshot)? Would it be possible? Would it be merged to both B and C? Using which filename? -- Nicolas Sebrecht -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list