Re: RBD layering design draft

[Dan Mick <dan.mick@inktank.com>]

On 06/18/2012 11:01 AM, Sage Weil wrote:
> On Mon, 18 Jun 2012, Josh Durgin wrote:
>>>>      $ rbd copyup pool2/child1
>>>
>>> Does "copyup" make sense to everyone? Every time you say it, my brain
>>> needs to flip the image inside the other way around -- I naturally
>>> imagine a tree with the parent at the top, and children and
>>> grandchildren down from it, but then I can't call that operation
>>> "copyup" without wrecking my mental image.
>>>
>>> I also can't seem to google good evidence that the term would be in
>>> widespread use in the enterprisey block storage world, outside of the
>>> unionfs world.. What do people call the un-dedupping, un-thinning of
>>> copy-on-write thin provisioning?
>>>
>>> "unshare"?
>>
>> I'm not sure what best term is, but there's probably something better than
>> copyup.
>
> "flatten"?  My mental model is stuck on the "layering" analogy, where the
> child is a copy-on-write layer on top of a read-only parent.
>
> Someday we may want to support the ability to add a parent to an existing
> image and do a sort of "dedup", so having an opposite for whatever term we
> pick would be a bonus.

"disown" and "adopt"?  :)  (actually I started as a joke, but really I 
kinda like that; fits with the parent-child name)