I'm working on an release of our cloud infrastructure platform using Sheepdog to provide drive storage instead of LVM LVs + iscsi as at present. Part of our system is a drive clone facility, which makes a new drive as a clone of the (current state of) an existing drive. We want to (continue to) expose a simple concept of a drive to users, rather than distinct drive and snapshot objects, with snapshots having a subset of the facilities of drives. I have done a preliminary implementation of this as - qemu-img snapshot the source vdi - find the snapshot id of this snapshot with collie vdi list - qemu-img create a new vdi using the newly-created snapshot as a base - collie vdi delete the temporary snapshot of the source vdi It all seems to work quite nicely, but I wonder whether there are any potential issues with creating lots of very ephemeral snapshots like this? The vdi IDs will obvious get fairly large, but that is presumably not a disaster in itself, unless there are also internal resources being used very inefficiently by a pattern like this? Cheers, Chris. |