From: Paul Sladen (vserver_at_paul.sladen.org)
Date: Sat 10 Aug 2002 - 12:55:00 BST
On Sat, 10 Aug 2002 ragnar_at_this.is wrote:
>
> Is there a file system that does transparent unify?
This means that when an application closes a file you'd have to compare it's
contents to every other file on the system to see if you could find one that
matched with the same length and contents; i.e. O(n^2)
The shotcut we're [ab]using here is that we know that:
/foo/some/lib.so
is much more /likely/ to have the same contents and length as:
/bar/some/lib.so
If you trying to add this sort of problem to a mid/low-level system such as
a filesystem then you are introducing *alot* of complexity into something
that you would much rather was reliable through simplicity. As with many
problem a codepath that is flat, or at least O(N) is much nicer to work with
than one that can potentially scale out of control.
If you *really* wanted to do it you could possibley do something by means of
a filesystem `proxy' so that you weren't touching known-good working code
and you could probably do this type of thing [mostly] in userspace, but IMHO
a cron job running once a day and comparing hashes is probably the best
trade-off.
-Paul
-- Nottingham, GB