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Re: Do integrity checks by file comparison really work?

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Robert Wessel wrote:
> On Wed, 16 Jan 2013 11:38:54 +0100, Thomas B <thomasb@nospam.it>
> wrote:
>>
>> You wrote: "I've never seen an OS that would share file buffers between
>> two files like that", so I suppose this should be the same for files on
>> the same volume.
>
>
> Some OS's/filesystems can do a copy with the equivalent of a *nix hard
> link, and then do a copy-on-write procedure if the file is ever
> modified.  In that case you may have only a single copy of the file.
> It can't do that to you across volumes.

ZFS is a good example.  If you snapshot or clone a filesystem, no extra 
space is used until it (a clone) or the source are modified.

ZFS also checksums its data, so there is no need to use another tool to 
validate copes.

-- 
Ian Collins

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Thread

Do integrity checks by file comparison really work? Thomas B <thomasb@nospam.it> - 2013-01-08 13:04 +0100
  Re: Do integrity checks by file comparison really work? Robert Wessel <robertwessel2@yahoo.com> - 2013-01-13 05:04 -0600
    Re: Do integrity checks by file comparison really work? Mark F <mark53916@gmail.com> - 2013-01-13 09:26 -0500
      Re: Do integrity checks by file comparison really work? Mark F <mark53916@gmail.com> - 2013-01-13 09:40 -0500
    Re: Do integrity checks by file comparison really work? Thomas B <thomasb@nospam.it> - 2013-01-16 11:38 +0100
      Re: Do integrity checks by file comparison really work? Robert Wessel <robertwessel2@yahoo.com> - 2013-01-18 15:07 -0600
        Re: Do integrity checks by file comparison really work? Ian Collins <ian-news@hotmail.com> - 2013-01-19 17:12 +1300
          Re: Do integrity checks by file comparison really work? Robert Wessel <robertwessel2@yahoo.com> - 2013-01-18 22:37 -0600
            Re: Do integrity checks by file comparison really work? Ian Collins <ian-news@hotmail.com> - 2013-01-19 18:36 +1300
        Re: Do integrity checks by file comparison really work? Thomas B <thomasb@nospam.it> - 2013-01-19 14:06 +0100
          Re: Do integrity checks by file comparison really work? Robert Wessel <robertwessel2@yahoo.com> - 2013-01-21 03:40 -0600
            Re: Do integrity checks by file comparison really work? Thomas B <thomasb@nospam.it> - 2013-01-21 17:41 +0100
              Re: Do integrity checks by file comparison really work? Robert Wessel <robertwessel2@yahoo.com> - 2013-01-21 15:28 -0600
  Re: Do integrity checks by file comparison really work? Willem <willem@turtle.stack.nl> - 2013-01-14 18:23 +0000
    Re: Do integrity checks by file comparison really work? Thomas B <thomasb@nospam.it> - 2013-01-16 16:46 +0100
      Re: Do integrity checks by file comparison really work? Robert Wessel <robertwessel2@yahoo.com> - 2013-01-18 15:09 -0600

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