A few quick ZFS thoughts

by Erica Sadun

Jeremiah Foster has already posted that ZFS, the open-source 128-bit file system, is coming to Leopard. I just wanted to add that where ZFS totally rules is in handling multiple disks, creating virtual storage pools that span more than one physical device.

Other cool stuff includes "snapshots" that retain access to unchanged data for updated files and which create read-only restore points, "copy-on-write" that keeps the file system from overwriting live data, and dynamic striping, which boosts system throughput while distributing the write-load across storage devices. And that's not even mentioning OS-integrated check summing for data integrity.

I'm not sure that ZFS will entirely replace HFS+ any time soon, but it's nice to see that Apple is moving in the right direction. I haven't had a huge amount of exposure to ZFS, so if any of you Sun Microsystems-type folk want to chime in, please let us know your thoughts about the file system.


Joerg Moellenkamp
2006-12-20 23:03:13
I am a Sun Microsystems guy, a die-hard Solaris admin and a fanatic Mac User. And my personal opinion is, that ZFS brings the ease of handling a mac to the handling of its storage. No more symbolic link hacks when itunes and iphoto folder gets to big. I've summarized my thoughts in my own blog: http://www.c0t0d0s0.org/archives/2410-Why-ZFS.html
2006-12-28 02:50:18
ZFS has no Boot-Support, because it was designed for massive Data-Storage-Solutions. So currently it can't replace HFS+, but they work on that point.
2007-01-08 00:38:56

I am sorry to sound cynical, but here is a thought for what its worth.

First of all, I've read the ZFS last word PDF from Sun and it is magical. ZFS, if it does everything Sun says it can do, is a wicked breakthrough in file systems (the first in decades). However, what does this mean for companies who have invested tons of money into hardware RAID solutions? For example, Apples' XSAN products? Clearly, why would Apple want to bring the full capabilities of ZFS to Apple hardware when it might mean sales opportunity losses? So in other words, I can't help but wonder if Apple's port of ZFS will in some ways cripple the full capability of ZFS such that Apple can continue to sell hardware mass storage and RAID products requiring expensive hardware options such as fiber channel? Remember, in the ZFS last word PDF, the author states that ZFS will work great with CHEAP storage hardware. My goodness, now that the cat is out of the bag, won't there surely be anti-ZFS FUD spread by the likes of businesses that have legacy investments in storage technology?