Open Stack

On 07/18/2018 03:43 PM, melanie witt wrote:
> On Wed, 18 Jul 2018 15:14:55 -0500, Matt Riedemann wrote:
>> On 7/18/2018 1:13 PM, melanie witt wrote:
>>>> Can we get rid of multi-create?  It keeps causing complications, and
>>>> it already
>>>> has weird behaviour if you ask for min_count=X and max_count=Y and only X
>>>> instances can be scheduled.  (Currently it fails with NoValidHost, but
>>>> it should
>>>> arguably start up X instances.)
>>> We've discussed that before but I think users do use it and appreciate
>>> the ability to boot instances in batches (one request). The behavior you
>>> describe could be changed with a microversion, though I'm not sure if
>>> that would mean we have to preserve old behavior with the previous
>>> microversion.
>> Correct, we can't just remove it since that's a backward incompatible
>> microversion change. Plus, NFV people*love*  it.
>
> Sorry, I think I might have caused confusion with my question about a
> microversion. I was saying that to change the min_count=X and max_count=Y
> behavior of raising NoValidHost if X can be satisfied but Y can't, I thought we
> could change that in a microversion. And I wasn't sure if that would also mean
> we would have to keep the old behavior for previous microversions (and thus
> maintain both behaviors).

I understood you. :)

For the case where we could satisfy min_count but not max_count I think we 
*would* need to keep the existing kill-them-all behaviour for existing 
microversions since that's definitely an end-user-visible behaviour.

Chris