[OpenAFS-devel] AFS + Object Storage

[Jeffrey Hutzelman]

On Wednesday, May 02, 2007 04:23:08 PM +0200 Hartmut Reuter 
<reuter@rzg.mpg.de> wrote:

> As I announced at the Hackathon-06 we are working on a combination of AFS
> and object storage. This project was created in 2005. It was a
> co-operation between Rainer Toebbicke from CERN, Andrei Maslennikov,
> Ludovico Giammarino, and Roberto Belloni from CASPUR, and me from RZG.
>
> The project has made good progress so that I would like to propose to put
> the source now into the OpenAFS CVS tree.
>
> Our source is based on the stable 1.4.4 release and can be found under
> /afs/ipp-garching.mpg.de/.cs/openafs/openafs-1.4.4-osd. For all files we
> changed we let the original version in place with a suffix ".orig".
>
> There is also a doc-subdirectory with two pdf-files: one is a description
> of what exists and the other one is a presentation I gave last week at
> the Spring HEPIX 2007 meeting in Hamburg.
>
> RZG is using this code already in production for normal AFS volumes, but
> has enabled the use of object storage only for a few selected volumes.
> The reason for not enabling object storage for all volumes is that we
> don't want to make massive use of features in OpenAFS which have not yet
> been approved by the OpenAFS commitees.
>
> There is still missing a lot, but on the other hand it's time to start
> beta-testing to find out all the nice bugs we have hidden under the
> surface!


I suspect this is going to be way too big a change for 1.4.x.  It might be 
reasonable to integrate this into 1.5, but you really want to prepare 
patches (using diff -ru) against the head.  Patches are much easier to read 
and review than is a modified source tree, and it is less likely that a 
gatekeeper will screw up when applying your patch than that he will do so 
when trying to manually port your changes, especially if they are large.

I'm sure I must have asked this during the hackathon, but does your work 
require the use of new RPC numbers or new values for other protocol fields? 
If so, you should send a request to registrar@central.org detailing what 
you need new values for, so that appropriate values can be assigned.  It's 
actually best if you do this early, to avoid situations where different 
people have used the same number for different purposes.  This is 
especially important because current OpenAFS source generally does not 
reflect all of the numbers that have been assigned.

In general, submitting patches to OpenAFS is not the way to modify the AFS 
wire protocol.  Instead, protocol changes should first be brought up on the 
afs3-standardization mailing list, which is the official forum for 
discussing changes to the AFS protocols.  Again, it is best to bring up 
proposed changes before getting too far with the implementation, to limit 
the amount of wasted effort if the mailing list has objections or 
suggestions for improvement.


-- Jeffrey T. Hutzelman (N3NHS) <jhutz+@cmu.edu>
   Sr. Research Systems Programmer
   School of Computer Science - Research Computing Facility
   Carnegie Mellon University - Pittsburgh, PA