[OpenAFS-devel] Patches for Openafs compression support

[Mitch Collinsworth]

On Wed, 5 Jan 2005, Jeffrey Hutzelman wrote:

>> Do we want to implement compression as seperate calls for every thing
>> that we want to compress or should we be able to switch it on/off
>> like encryption?
>
> Actually, what I'd like to see is an extension to the dump file format to 
> allow for compressed dumps.  In this model, "new" volservers would 
> automatically generate compressed dumps if the feature was enabled, and would 
> always be able to accept either kind of dump.  No new RPC's would be added 
> (*), and no changes to any clients would be required.  The compressed part of 
> the dump should begin with the vnodes, leaving the dump and volume headers 
> uncompressed for tools which expect to be able to parse these.

Thank you!  This is what I'm concerned about.  Our tools to backup AFS
using Amanda parse the dump file format in order to generate an index
of files.  If the volume headers are kept uncompressed then this should
not be a problem.

Of course the other solution would be an interface that does the dump
file parsing and presents a consistent API for external tools to use.
Then we wouldn't need to be on guard against file format changes.  :-)

-Mitch