Re: [PATCH] Add delta metadata generator to createrepo

On Tue, Jul 23, 2013 at 04:15:23PM +0200, Zdenek Pavlas wrote:
> This adds the following options:
> 
> --deltamd <a persistent per-repository directory>
> --deltamd-types <list of mdtypes>
> --deltamd-sizes <list of delta thresholds>
> 
> We create up to N deltas for each mdtype where N is the number
> of values specified with --deltamd-sizes.  The same delta file
> may be used to update from more than one version.
> 
> We start with the most recent version and keep adding older ones
> until the estimated delta size hits the first threshold. A single
> combined delta is created.  We continue with the next threshold,
> again packing as much versions as possible.
> 
> The delta files contain literals (prefixed with +<size>/n)
> and old data references.  Since we don't reorder chunks the
> references are interpreted as "skip until the matching
> one is found".  This allows us to use prefixes and since
> all source versions are known we can use the shortest one,
> often just an empty string plus terminating newline.

Hmm, I'm don't think I get that. Do you have an example repository
with deltas somewhere?

Thanks,
  Michael.

-- 
Michael Schroeder                                   [email protected]
SUSE LINUX Products GmbH,  GF Jeff Hawn, HRB 16746 AG Nuernberg
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