[sheepdog] [RFC PATCH] farm: don't check of the existing object before slice_write

[MORITA Kazutaka]

At Fri, 19 Jul 2013 13:17:53 +0800,
Liu Yuan wrote:
> 
> On Fri, Jul 19, 2013 at 02:09:23PM +0900, MORITA Kazutaka wrote:
> > At Fri, 19 Jul 2013 13:02:54 +0800,
> > Liu Yuan wrote:
> > > 
> > > On Fri, Jul 19, 2013 at 01:33:16PM +0900, MORITA Kazutaka wrote:
> > > > Currently, we stores sliced objects for the farm store, so
> > > > sha1_file_exist() fails always.
> > > > 
> > > > Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
> > > > ---
> > > > 
> > > > Other approaches are:
> > > > 
> > > >  - Calculate the sha1 digest before slicing objects and store the
> > > >    value to the farm store so that sha1_file_exist() can check it.
> > > >
> > > >  - Make sheep return the hash value of the sliced data.
> > > > 
> > > > Any suggestions?
> > > 
> > > I don't understand this patch. Does it solve any exsiting problem?
> > > Why sha1_file_exist() will fail? Every object will have a unquie sha1 as
> > > before after stored into farm.
> > 
> > Farm stores only sliced objects, no?  sd_read_object_sha1() calculates
> > a sha1 digest against a whole object (not sliced data).
> > 
> 
> Ah, I see the point. For a quick thought, there won't be many objects with the
> same content in images, so removing pre-check looks fine.

Okay, then this patch can be applied without change?

Thanks,

Kazutaka