gsnapshot around ?

[Eric Anderson]

On 12/05/06 16:08, Ivan Voras wrote:
> Eric Anderson wrote:
> 
>> I've been thinking a bit about this for a while.  It would be a great
>> tool to have, certainly.   Does anyone have any particular
>> implementation ideas?
> 
> It's actually not that hard to do. I really want the possibility to save
> snapshot data in a file (as opposed to dumping it to another GEOM
> device), and PJD had some file-muching kernel code so it's definitely
> doable right now.
> 
> I'm still waiting on a "hot-plug" insertion of GEOM classes in between
> two classes to make it really usable for the common man :)


I've been thinking about a layered approach, so the gsnapshot would 
create a 'layer', and all new writes would go to the layer.  Then, there 
would be another class, to stack layers (kind of like unionfs, except 
for block devices) - so when you wanted to view the data on a snapshot, 
you would stack the layers how you wanted, and then see the data.  Kind 
of like journaling, kind of like regular COW, etc, but a little more 
Unix-style-ish in the manner of a few building blocks that can be used 
in many ways, and stacked together to make something powerful.


Eric


-- 
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Eric Anderson        Sr. Systems Administrator        Centaur Technology
An undefined problem has an infinite number of solutions.
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