> There is no 40 filesystem limit. You most likely had a pre-existing > file/directory in testpool of the same name of the filesystem > you tried to create.
I'm absolutely sure that I didn't. This was a freshly created pool. Having said that, I recreated the pool just now and tried again and it worked fine. I'll let you know if I manage to repeat the previous problem. > So this really depends on why and when you're unmounting > filesystems. I suspect it won't matter much since you > won't be unmounting/remounting your filesystems. I was thinking of reboot times, but I've just tried with 1000 filesystems and it seemed to be much quicker than when I mounted them one-by-one. Presumably there's a lot of optimisation that can be done when all filesystems in a pool are mounted simultaneously. I've noticed another possible issue - each mount consumes about 45KB of memory - not an issue with tens or hundreds of filesystems, but going back to the 10,000 user scenario this would be 450MB of memory. I know that memory is cheap, but it's still a pretty noticeable amount. > >Others have already been through the problems with standard > >tools such as 'df' becoming less useful. > > Is there a specific problem you had in mind regarding 'df;? The fact that you get 10,000 lines of output from df certainly makes it less useful. Some awkward users, and we have plenty of them, might complain (possibly with some justification) that they would prefer that other users not be able to see their quota and disk usage. And I've found another problem. We use NFS, and currently it's pretty straightforward to mount thing:/export/home on another box. With 10,000 filesystems it's not so straightforward - especially since the current structure (which it would be annoying to change) is /export/home/XX/username (where XX is a 2 digit number). The ability to mount a tree of ZFS filesystems in one go would be useful. I know the reasons for not doing this on traditional filesystems - does they apply to ZFS too? > I wouldn't give up that easily... looks like 1 filesystem per > user, and 1 quota per filesystem does exactly what you want I'm not giving up! My thought is that ZFS presents a *huge* change, and retaining 'legacy' quotas as an optional mechanism would help to ease people into it by allowing them to change a bit more gradually. In our case - we have an upgrade of a 10,000 user system scheduled for later this summer - I think the differences are too great. If we were able to start with one filesystem and then slice pieces off it as we gain more confidence we'd probably use zfs. As it is I think we'll try zfs on smaller systems first and maybe think again next summer. Thanks for your help. Steve. This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
