On Sun, Dec 16, 2007 at 02:17:33PM -0800, Andrew Lentvorski wrote:
Second, ZFS has lots of on-disk checking with copy-on-write semantics. This means that your old data is never lost by a write, and your new data relies on a read and whether the checksum validates to establish that the transaction is done.
This aspect of ZFS sounds very nice. Reiser4 was trying to do something similar, but never really did anything useful with it. We could hope that a write followed by a read of the same data would actually read it from disk, but I'm guessing it doesn't unless you explicitly flush out the cache.
Eventually, ZFS (or something like it) will win.
Hopefully sooner rather than eventually :-). It is kind of understandable why filesystem technology changes so slowly, given how critical it is to the operation of the OS. I mean Vista still has an essentially offline defragmenter (with a hidden UI, just to make it annoying). At least Apple managed to get online defragmentation into their OS. It seems that most systems out there are running filesystems still basically derived from FFS. Other than ZFS, the alternatives don't really _do_ anything different, at least as far as functionality. I appreciate the effort SGI has put into xfsdump, and that is why I'm using XFS on my machines. Dave -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
