Open Stack

John Griffith wrote:
> [...]
> Anyway, I'd like to get some feedback from the TC on all of this.
>  Whether it be an official agenda item for an upcoming meeting, or at
> the very least feedback to this email.  In my opinion this is very much
> a TC item and is exactly the sort of thing that the TC should be
> interested in.  I can certainly make decisions on my own based on
> feedback from the rest of the Cinder community and my own personal view,
> however I believe this has a broader impact. 

The TC is responsible for the "scope" of OpenStack and making sure we
spend our common resources where they are the most needed, so I think
it's relevant for us to at least give our opinion there.

There are IMHO two different issues here. The first is a technical
issue: what type of functionality you want your drivers to cover. In
Cinder, drivers should be a relatively thin indirection layer where you
implement the glue between the Cinder driver API on one side and what
the pure storage backend expects on the other. They are not really
supposed to be big or reimplement advanced scheduling features.
Accepting such monster drivers in mainline code changes the relative
weight of code areas in cinder and therefore makes it a costly
maintenance proposition for the project, with little on the benefits
side compared to growing that driver out of tree.

The second issue is more of a social issue: we want as much as possible
of the smart in Cinder being implemented in open source in OpenStack. If
vendors decide to implement the smart parts in closed source software
shipped in storage hardware gateways, they may win but OpenStack surely
loses.

I think it's a perfect example of where out-of-tree makes the most
sense: when the added value to the project is limited (or negative),
while the benefit for one vendor is enormous.

The other classic example of this is the Nova VMWare support... and it's
questionable as well on both counts. That said the dynamics are slightly
different there, VMWare being the legacy standard for old-style
datacenter virtualization, supporting it is a decent way to co-opt that
ecosystem and encourage migrating off it.

-- 
Thierry Carrez (ttx)