> From: Joerg Schilling [mailto:joerg.schill...@fokus.fraunhofer.de] > > Are you sure that MS solved the problem of finding the most recent > superblock > in a COW filesystem and are you sure that MS solved how to make "cheap" > snapshots?
I didn't say anything about MS finding the most recent superblock. I don't even know if MS has any such concept in NTFS. I do know they can make "cheap" snapshots via VSS. It's only available in Servers, not desktops. When I build a Windows fileserver, I enable snapshots, taken regularly, and the behavior and end result is almost identical to ZFS and Netapp snapshots. The scheduled "snapshot" command completes essentially instantly, and then a read-only copy of everything from that moment of time is available for browsing and restore. There is a difference in how you access it ... In Netapp and ZFS, you browse to a special directory. In windows, you right-click something and go to "previous versions." There is also a difference in how old snapshots are handled. In netapp and ZFS, snapshots stay until they're deleted by automated scripts or admin intervention. If the disk fills up, the disk fills up. In MS, the oldest snapshot is automatically deleted when the disk fills up, so there's never a need to automatically or manually delete snapshots. You just leave snapshots laying around forever. _______________________________________________ opensolaris-discuss mailing list opensolaris-discuss@opensolaris.org
