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Date: Sun, 24 Oct 2010 16:28:36 +0100
From: Bruce Cran <bruce@cran.org.uk>
To: Matthew Seaman <m.seaman@infracaninophile.co.uk>
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Cc: cronfy <cronfy@gmail.com>, freebsd-hackers@freebsd.org
Subject: Re: Slow disk access while rsync - what should I tune?
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On Sun, Oct 24, 2010 at 04:18:51PM +0100, Matthew Seaman wrote:
> 
> However, taking backups slowly makes it harder to ensure you have a
> consistent backup, so I recommend you investigate snapshotting the
> filesystem (well supported for UFS, trivially easy for ZFS) and then
> backup the snapshot as slowly as you like.

I'm not sure snapshots are so well supported for UFS.
>From sys/ufs/ffs/README.snapshot:

"As is detailed in the operational information below, snapshots are
definitely alpha-test code and are NOT yet ready for production use."

-- 
Bruce Cran