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On 10/27/2014 06:18 PM, Jesse Cook wrote:
> In the glance mini-summit there was a request for some documentation on
> the architecture ideas I was discussing relating to: 1) removing data
> consistency as a concern for glance 2) bootstraping vs baking VMs
>
> Here's a rough draft: https://gist.github.com/CrashenX/8fc6d42ffc154ae0682b

Hi Jesse!

A few questions for you, since I wasn't at the mini-summit and I think 
don't have a lot of the context necessary here...

1) In the High-Level Architecture diagram, I see Glance Middleware 
components calling to a "Router" component. Could you elaborate what 
this Router component is, in relation to what components currently exist 
in Glance and Nova? For instance, is the Router kind of like the 
existing Glance Registry component? Or is it something more like the 
nova.image.download modules in Nova? Or something entirely different?

2) The Glance Middleware. Do you mean WSGI middleware here? Or are you 
referring to something more like the existing nova.image.api module that 
serves as a shim over the Glance server communication?

3) Images in Glance are already immutable, once the image bytes are 
actually uploaded to a backend block store. What conceptual differences 
are you introducing with the idea of object immutability?

4) How does the glance_store library play into your ideas, if at all?

5) How does the existing "image locations" collection in the Glance v2 
API work with your ideas? With an image uploaded to multiple locations 
(in Swift, Ceph clusters, wherever...), is the Router object in your 
architecture the thing that determines affinity for the best 
storage-locality to pull data from?

All the best,
-jay