Re: [linux-lvm] 'snapshot' target still experimental :-(

["Brian J. Murrell" <brian@interlinx.bc.ca>]

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On Wed, 2006-02-01 at 13:29 -0800, Dan Stromberg wrote:
> It just maintains a series of hardlink trees, so any time a file is
> deleted or added, the actual disk usage increase is only due to the
> changes.

Yes, this is quite a popular technique.  To be clear though, a change in
a file does not consume just the amount of the change in the file on the
backup target, but it consumes the entire size of the new file.  A
not-so-insignificant amount for very large files.  This is where a
(block level or filesystem level) snapshotting scheme would excel as it
would likely only consume an amount of space rounded up to the next
"unit" size more even for changes within a file.

Indeed (and to keep quite on topic), perhaps rather than hardlink trees,
LVM snapshots would be even more space efficient.  Maybe that is what
this thread has been about.  I just jumped in.  Apologies if it was.

b.

-- 
My other computer is your Microsoft Windows server.

Brian J. Murrell

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