> When you do it using fssconfig(8), you specify a backing store on the > same filesystem? No.
The file systems I snapshot are on a (slow) 4+1-disc level 5 RAIDframe on 3TB 7k2 SAS discs (via mpt) while the backing store is in /var, which is on a (fast) 1+1-disc level 1 RAIDframe on 146GB 15k SAS discs. The snapshots are normally held only for about half an hour, but they were sometimes accidently held for half a day or more, and the snapshotted file systems remained usable.
