[sheepdog] [PATCH RFC] add support of sheepdog backing store

[ronnie sahlberg]

On Thu, Sep 26, 2013 at 6:59 PM, Dan Mick <dan.mick at inktank.com> wrote:
>
>>> Some might say this had better to be a dynamic loadable
>>> library. Either is fine by me because it doesn't depend on any
>>> original C header files.
>>
>>
>> I'm ccing people who would be interested in modular backing
>> stores, Ronnie Sahlberg and Andy Grover. I think the sheepdog backing
>> store support doesn't have to be a module because it doesn't create
>> any new dependencies. Any comments?
>
>
> It seems that you've accomplished this by including structure and constant
> definitions (and presumably protocol-marshalling routines) in the tgt source
> file itself, which seems to me to be the wrong way to do it, but it does
> free you from requiring headers or libraries, so
> technically speaking, true.
>
> I wouldn't write the plugin this way (copying code), but that's me.


What Dan said!
Since you don't add any new dependencies it shouldn't matter if this
is built-in or a module.

However, you do this at the cost of having a full blown
re-implementation (or it is a copy?) of a sheepdog client in the
backing store file.
I assume there are client libraries for sheepdog available?

So I think from a maintenance viewpoint, it would probably be better
if you had the backend just be a thin layer that would call out to and
link to the sheepdog client library.
I.e. link to a sheedog library instead of reimplementing it in the backend.
And in that case then this should be a module.


regards
ronnie sahlberg