On Fri, Oct 06, 2006 at 11:57:36AM -0700, Matthew Ahrens wrote: > [EMAIL PROTECTED] wrote: > >On Fri, Oct 06, 2006 at 01:14:23AM -0600, Chad Leigh -- Shire.Net LLC > >wrote: > >>But I would dearly like to have a versioning capability. > > > >Me too. > >Example (real life scenario): there is a samba server for about 200 > >concurrent connected users. They keep mainly doc/xls files on the > >server. From time to time they (somehow) currupt their files (they > >share the files so it is possible) so they are recovered from backup. > >Having versioning they could be said that if their main file is > >corrupted they can open previous version and keep working. > >ZFS snapshots is not solution in this case because we would have to > >create snapshots for 400 filesystems (yes, each user has its filesystem > >and I said that there are 200 concurrent connections but there much more > >accounts on the server) each hour or so. > > I completely disagree. In this scenario (and almost all others), use of > regular snapshots will solve the problem. 'zfs snapshot -r' is > extremely fast, and I'm working on some new features that will make > using snapshots for this even easier and better-performing. > > If you disagree, please tell us *why* you think snapshots don't solve > the problem.
Matt, think of night when some (maybe 5 %) people still work. Having snapshot I would still have to create snapshots for 400 filesystems each hour because I don't know which of them are working. And what about weekend ? Still 400 snaphosts each hour ? And 'zfs list' will list me 400*24*2=19200 lines ? And how about organizations which has thousends people and keep their files on one server ? Or ISP/free e-maila account providers who have millions ? Imagine just ordinary people who use ZFS in their homes and forgot creating snapshots ? Or they turn their computer on once and then don't turn it off: they work daily (and create snapshot an hour) and don't turn it off in the evening but leave it working and downloading some films and musics. Still one snapshot an hour ? How many snapshot's a day, a week a month ? Thousands ? And having ZFS which is _so_easy_ to use does managing so many snapshots is ZFS-like feature ? (ZFS-like = extremely easy). The way ZFS is working right now is that it cares about disks (checksumming), redundancy (raid*) and performance. Having versioning would let ZFS care about people mistakes. And people do mistakes. Yes, Matt, you are right that snapshots are a feature which might be used here but it is not the most convenient in such scenarios. Snapshots are probably much more useful then versioning in "predictable" scenarios: backup at night, software development (commit new version) etc. In highly unpredictable environment (many users working in _diferent_ hours in different part ot the world) you would have to create many thousands of snapshots. To deal with them might be painfull. Matt, I agree with you that having snapshots *solve* the problem with 400 filesystems because in SVM/UFS environemnt I _wouldn't_ have such solution. But I feel that versioning would be much more convenient here. Imagine that you are the admin of the server and ZFS has versioning: having a choice what would you choose in this case ? przemol _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
