Compressing packages with bzip2 instead gzip?

Phillip Susi psusi at
Wed Jan 18 16:49:07 GMT 2006

Aigars Mahinovs wrote:
> And what happend to user-changed files, for example, config files?
> zsync would recompress the deb, try to get the diff from the server
> and fail, because the server would not have the changeset that would
> apply to that _modified_ deb. And the zsync would have to download the
> whole .deb anyway.

No, it would zsync the config file inside the deb, so it would update 
the user's config file with the deltas from the server.  As I understand 
it, the beauty of rsync/zsync is that it does not rely on the server 
generating a diff between two files, so the server and client don't both 
have to have exact copies of the old file, and they can still sync up.

Even if the client has to download a complete fresh copy of the config 
file, so what?  Most of the space savings will be in the binaries.

> I cann't think of a solution to this that would not require a way for
> client to get a single specific file of a .deb from the server. And at
> that point we are basically rsyncing a part of the filesystem tree
> with the server and storing the result in a .deb.

That's the idea; you rsync the uncompressed files inside the deb, not 
the deb itself.  That way you don't get bloated diffs due to small 
changes in the uncompressed files resulting in large changes in the 
compressed data.  Also the client doesn't have to still have the old deb 
in his apt cache.

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