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ZFS Shows Up in New Leopard Build
Udo Schmitz writes "As a follow-up to rumours from May this year, World of Apple has a screenshot showing Sun's Zettabyte File System in "the most recent Build of Mac OS X 10.5 Leopard". Though I still wonder: If it is not meant to replace HFS+, could there be any other reasons to support ZFS?"
Isn't the term 'Zettabyte File System' actually inaccurate now? I thought they dropped that and ZFS now only remains as a pseudo initialism
I never get used to these constant resurrections
ZFS = snapshoots = Time Machine5 /4995/
http://arstechnica.com/staff/fatbits.ars/2006/8/1
A clicky to the Wiki article on ZFS.
"I use a Mac because I'm just better than you are."
I've never found plain-Jane posix permissions to be all that useful on anything other than the most basic of server environments. ...
What I'd really like to see is both that kind of functionality along with NTFS's really excellent ACL permission system implemented.
I wish you could read more about ZFS before suggesting how you could improve it by adding ACLs. It already supports them!
http://blogs.sun.com/marks/entry/zfs_acls
)9TSS
There are no tiger attacks in my area and it's all because this rock I'm holding keeps the tigers away.
A deadline scheduler (a-la ZFS) is wonderful when multitasking disk heavy apps. That does not happen too often on a laptop (or a desktop, for that matter), but I've had Windows (and on rare occasions, even Linux) work horribly under such load. ZFS' "worst case behaviour" is supposed to be significantly better than any other system in use today.
NTFS's ACL system is horrible. While it has a lot of descriptive power, it's a pain to manage, the result being that it is almost never used. The old Unix model, while simple, is easy to manage, and as a result is often set up reasonably. Novell's "Trustees" model works much better than either, but for some reason it wasn't adopted by others.
NTFS is slow and inefficient, fragments horribly, and lacks fundamental features such as proper symlinks (and only supports directory hardlinks). It has a reasonable journal implementation, and it supported large files before other systems did, but it's very outdated and does not compare favourably with any of the modern high performance file systems.
You both miss the point of HFS+ and ZFS. In Solaris ZFS has not replaced UFS. ZFS is an elegant way to manage large amounts of storage tied together with inexpensive and simple SATA drives. If you have one disk in your Mac, ZFS probably will not be your choice. HFS+ will work very well and be very easy to manage. A file server with 3 or 4 750 GB drives however, might be cut up so that part of the storage is mirrored for safety, limited for certain uses, and spanned over drives for size. For example, 3 750's could be divided into 1 TB unmirrored storage, 250 GB mirrored, a temp area of up to 100GB and the rest (650+ GB depending on temp are usage) held in reserve. In addition ZFS does quite a bit of error checking on the data to avoid any possible corruption during reads. However, it will never replace HFS+ on an iMac for your average user.
Leave the gun, take the cannoli -- Clemenza, The Godfather
Hard drives silently losing data is a problem solved by RAID.
_ data
That is profoundly wrong. Vanilla RAID will not discover and cannot automatically correct silent data loss. The reason is that RAID has no way of knowing which data is correct. For example, if two mirrored copies disagree on the contents of a block, the data is unrecoverable without manual intervention or external knowledge. Furthermore, in normal operation your RAID subsystem will simply read data from whichever drive is idle at the time the read request comes in; it does not ordinarily compare the two mirrors. The data will remain corrupted until the user notices a problem, at which point they have no practical recourse. Essentially the same problem occurs with parity RAID.
There is no dedicated hardware in your system that provides the end to end data integrity that ZFS does. I honestly suggest you learn more about it before airing your opinions. Here is a start:
http://blogs.sun.com/bonwick/entry/zfs_end_to_end
does some funky heuristic happen?
Yes, I used something similar to ZFS for mass document storage a few years back. You do a complex checksum on the block level. Any two blocks with the same sum are the same. Each unique block is only stored once, though multiple files might link to it. You're right the file system doesn't know why you are using the same blocks over and over, but it doesn't care.
if i've got a bunch of files that take up 700mb on a ZFS device and try to back up to a (Joliet) CD will i get a message telling me that the CD doesnt have room?
Assuming you have repetitive block, yes.
Over past months, I've read a lot of people commenting on ZFS who have no idea what it is. What it is, is the next generation of filesystems, not a "tweak" of current fs technology. It just happens to "look like" an ordinary POSIX fs, from a distance (if you ignore the administration/pool stuff...) But inside, it's something new under the Sun, folks.
RAID experts don't grok it, because it does things RAID can't do (end-to-end).
Devotees of ext2fs, reiserfs (yay!), NTFS (LOL!), or HFS+ don't grok it, because none of those filesystems do what ZFS does.
Read about it before you write it off as old wine in a new bottle. To ask the question, "Does OS X need a new filesystem?" is a perfect example of missing the point. Once you've looked at what ZFS really brings to the table, you'll see why it's an inevitable future, sooner or later, and you'll stop looking foolish.
Some links I posted this week:
- http://www.osnews.com/story.php/16739/Screenshot-Z FS-in-Leopard
- http://mac4ever.com/news/27485/zettabyte_sur_leopa rd/
(older rumour http://www.osnews.com/story.php?news_id=14473)
For OS X people wondering why the fuss about ZFS - summaries include: - http://www.sun.com/2004-0914/feature/ - http://www.sun.com/bigadmin/features/articles/zfs_ part1.scalable.html
"Why ZFS for home": - http://uadmin.blogspot.com/2006/05/why-zfs-for-hom e.html
"Here are ten reasons why you'll want to reformat all of your systems and use ZFS.": http://www.tech-recipes.com/rx/1446/zfs_ten_reason s_to_reformat_your_...
And some more technical explanations from Chief Engineer: - http://blogs.sun.com/bonwick/entry/zfs_end_to_end_ data
- http://blogs.sun.com/bonwick/entry/smokin_mirrors
you had me at #!