[Sheepdog] [PATCH] sheep: use hash value for vdi attribute object id

[MORITA Kazutaka]

At Wed, 3 Aug 2011 13:50:32 +0100,
Chris Webb wrote:
> 
> MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp> writes:
> 
> > Sheepdog also uses a hash value of the vdi name to look up vdi
> > objects, so it is already difficult to implement vdi rename simply,
> > but I think it is not impossible.  For example, if we log all the vdi
> > rename operations, we can traverse the renamed vdi name and get the
> > correct hash value based on the old vdi name.
> 
> Or perhaps make the vdi 'name' an internal uniquely allocated 'id' value and
> the displayed name be an attribute of the vdi? (This is what I'm already
> doing with sheepdog in our system, as I want to be able to guarantee unique
> 'names'.)

Let me clarify some points.

In this approach, when we rename a vdi, we specify the vdi 'id' and
change the attribute of the vdi, yes?

What is specified in the qemu command line option as a Sheepdog volume
name?  Is it vdi 'name' (an attribute of the vdi) or vdi 'id' (the 32
bit integer)?


Thanks,

Kazutaka