Open Stack

On 02/24/2015 09:37 AM, Chris Dent wrote:
> On Tue, 24 Feb 2015, Sean Dague wrote:
>
>> That also provides a very concrete answer to "will people show up".
>> Because if they do, and we get this horizontal refactoring happening,
>> then we get to the point of being able to change release cadences
>> faster. If they don't, we remain with the existing system. Vs changing
>> the system and hoping someone is going to run in and backfill the 
>> breaks.
>
> Isn't this the way of the world? People only put halon in the
> machine room after the fire.
>
> I agree that "people showing up" is a real concern, but I also think
> that we shy away too much from the productive energy of stuff
> breaking. It's the breakage that shows where stuff isn't good
> enough.
>
> [Flavio said]:
>> To this I'd also add that bug fixing is way easier when you have
>> aligned releases for projects that are expected to be deployed
>> together. It's easier to know what the impact of a change/bug is
>> throughout the infrastructure.
>
> Can't this be interpreted as an excuse for making software which
> does not have a low surface area and a good API?
>
> (Note I'm taking a relatively unrealistic position for sake of
> conversation.)
I'm not so sure about that. IMO, much of this goes back to the question 
of whether OpenStack services are APIs or implementations. This was 
debated with much heat at the Diablo summit (Hi Jay). I frequently have 
conversations where there is an issue about release X vs Y when it is 
really about api versions. Even if we say that we are about 
implementations as well as apis, we can start to organize our processes 
and code as if we were just apis. If each service had a well-defined, 
versioned, discoverable, well-tested api, then projects could follow 
their own release schedule, relying on distros or integrators to put the 
pieces together and verify the quality of the whole stack to the users. 
Such entities could still collaborate on that task, and still identify 
longer release cycles, using "stable branches". The upstream project 
could still test the latest released versions together. Some of these 
steps are now being taken to resolve gate issues and horizontal resource 
issues. Doing this would vastly increase agility but with some costs:

1. The upstream project would likely have to give up on the worthy goal 
of providing an actual deployable stack that could be used as an 
alternative to AWS, etc. That saddens me, but for various reasons, 
including that we do no scale/performance testing on the upstream code, 
we are not achieving that goal anyway. The big tent proposals are also a 
move away from that goal.

2. We would have to give up on incompatible api changes. But with the 
replacement of nova v3 with microversions we are already doing that. 
Massive adoption with release agility is simply incompatible with 
allowing incompatible api changes.

Most of this is just echoing what Jay said. I think this is the way any 
SOA would be designed. If we did this, and projects released frequently, 
would there be a reason for any one to be chasing master?

  -David