>> >> The problem with that argument is that 10.000 users on one vxfs or UFS >> filesystem is no problem at all, be it /var/mail or home directories. >> You don't even need a fast server for that. 10.000 zfs file systems is >> a problem. >> >> So, if it makes you happier, substitute mail with home directories. >> > > If you feel strongly, please pile onto CR 6557894 > http://bugs.opensolaris.org/view_bug.do?bug_id=6557894 > If we continue to talk about it on the alias, we will just end up > finding ways to solve the business problem using available > technologies.
If I need to count useage I can use du. But if you can implement space usage info on a per-uid basis you are not far from quota per uid... > > A single file system serving 10,000 home directories doesn't scale > either, unless the vast majority are unused -- in which case it is a > practical problem for much less than 10,000 home directories. > I think you will find that the people who scale out have a better > long-term strategy. We have a file system (vxfs) that is serving 30,000 home directories. Yes, most of those are unused, but we still have to have them as we don't know when the student will use it. If this where zfs we would have to create 30,000 filesystem. Every file system has a cost in RAM and in performance. So, in ufs or vxfs unused home directories costs close to nothing. In zfs they have a very real cost. > > The limitations of UFS do become apparent as you try to scale > to the size permitted with ZFS. For example, the largest UFS > file system supported is 16 TBytes, or 1/4 of a thumper. So if you > are telling me that you are serving 10,000 home directories in > a 16 TByte UFS file system with quotas (1.6 GBytes/user? I've > got 16 GBytes in my phone :-), then I will definitely buy you a > beer. And aspirin. I'll bring a calendar so we can measure the > fsck time when the log can't be replayed. Actually, you'd > probably run out of inodes long before you filled it up. I wonder > how long it would take to run quotacheck? But I digress. Let's > just agree that UFS won't scale well and the people who do > serve UFS as home directories for large populations tend to use > multiple file systems. We have 30,000 accounts on a 1TByte file system. If we need to we could make 16 1Tb file systems, no problem. But 30,000 file systems on one server? Maybe not so good... If we could lower the cost of a zfs file system to zero all would be good for my usages. The best thing to do is probably AFS on ZFS. AFS can handle many volumes (file systems) and ZFS is very good at the storage. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
