[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Duplicity-talk] how much metadata does duplicity store between runs
From: |
Kenneth Loafman |
Subject: |
Re: [Duplicity-talk] how much metadata does duplicity store between runs |
Date: |
Sat, 28 Jun 2008 08:51:07 -0500 |
User-agent: |
Thunderbird 2.0.0.14 (X11/20080505) |
Sitaram Chamarty wrote:
> Hello all,
>
> I'm currently unable to install duplicity on my Mandriva system
> without jumping through quite a few hoops, so I thought I'd just ask
> instead of doing all that to find the answer to my question.
If the instructions are bad / not enough / wrong, please let me know.
> I know that librsync needs only a set of checksums for the old file,
> and the full new file. Since duplicity can work with almost any type
> of remote file system, I imagine it is not dependent on something
> running "on the other side" to generate those checksums (unlike plain
> rsync, for instance). Therefore I imagine that, when one run is done,
> it stores the checksums required for older versions locally, to be
> used as inputs for the next run.
That's what the signature files are about. Hashes are stored for each
block in a file. That way the incremental backup can store only changed
blocks.
> Is my understanding correct, and if so how much metadata (as a very
> rough fraction of the actual files being backed up) is stored. Very
> approximate numbers or guesses are also fine -- I'm mainly looking to
> see if I've understood this at all :-)
Well below 5% of the total backup would be metadata.
...Ken
signature.asc
Description: OpenPGP digital signature