After trying out ZFS using a couple of flash drives, I have to say that I’m impressed... Other than the fact that you have to use the command-line for a few options, it’s most impressive. (And being a Unix geek, the command-line is about as scary as watching a clock tick.)

I found that it’s easy to take two flash drives, plug them into the computer, make them into one ZFS pool - like a JBOD if using RAID on a different kind of FS. Then when I plug a flash drive in, the drive doesn’t show up or mount until the second one is plugged in. While I imagine it’s easy to recover what data is in the disk that’s plugged in, it’s a neat way to keep the ignorant from reading the disk - both have to be plugged in for it to work enough for the computer illiterate to use. Sorta like having a key to unlock the door.

The advantages ZFS offers are hard to ignore - it’s an amazing FS to work with. The only question in my head is whether Leopard will see full ZFS functionality, or if we’ll have to wait until the next release of OS X. Snapshots are something that already has a working interface - Time Machine. ZFS has a lot of things that even mere mortals will want to have.

It also makes me wonder... what is happening in the world of Linux filesystems? JFS, ReiserFS, and XFS are all essentially in maintenance mode, Reiser4 looks to be stillborn. Ext4 adds extents, and fixes a few outstanding limitations with ext3 - very evolutionary, and an improvement, yes. But ext4 doesn’t get many oohs and aahs; it’s an extremely conservative improvement. There’s certainly nothing in ext4 to get all excited about.

ZFS is an FS to get excited about - which is part of the problem, actually... it throws out a number of core assumptions that filesystems have used for most of my lifetime. It would take a lot of work (not to mention licensing miracles) to see a kernelspace implementation of ZFS on Linux.

Assuming ZFS doesn’t make it into the kernel, I’ll just have to hope that FUSE reaches a point where the performance penalty of being in userspace is small enough that I don’t care. The advantages of ZFS are simply too good for me to ignore, and Linux isn’t providing anything comparable.