Tim Connors wrote:
Do you use snapshots? Extensively?
Yes. The ZFS box (5.11 snv_111b i86pc i386 i86pc Solaris) is basically doing the same job as rsnapshot, except using daily rsync+zfs instead of daily rsync+hard links. Also noteworth -- until it ran out of disk, nobody had gotten around to expiring out old snapshots, so there were a LOT of them (probably around 1000 per backup). That would certainly increase the time to remove a single snapshot significantly, and AFAICT when you tell it to remove >1 snapshot it does so by removing them one at a time still.
Perhaps continual use of snapshots greatly fragments the pool.
NFI. I will happily concede that my ancedote is not a very reliable datapoint, but I'm gonna keep using ext until cmason rubber stamps btrfs as being 100% a-OK for production use.