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Cc: freebsd-fs@freebsd.org
Subject: Re: snapshot implementation
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On Wed, 23 Dec 2009 10:41:34 -0600 (CST), Bob Friesenhahn
<bfriesen@simple.dallas.tx.us> wrote:
> 
> I don't know anything about snapshots in UFS, but snapshots in ZFS are 
> certainly remarkably different.  ZFS uses copy-on-write (COW) whenever 
> a data block is updated


UFS snapshot also uses copy on write mechanism. So it's not so different
from ZFS snapshot.

patpro