Open Stack

Hi Joe,

Thanks for your reply, I'll try to further explain.


Le 03/03/2014 05:33, Joe Gordon a écrit :
> On Sun, Mar 2, 2014 at 11:32 AM, Dina Belova <dbelova at mirantis.com> wrote:
>> Hello, folks!
>>
>> I'd like to request Climate project review for incubation. Here is official
>> incubation application:
>>
>> https://wiki.openstack.org/wiki/Climate/Incubation
> I'm unclear on what Climate is trying to solve. I read the 'Detailed
> Description' from the link above, and it states Climate is trying to
> solve two uses cases (and the more generalized cases of those).
>
> 1) Compute host reservation (when user with admin privileges can
> reserve hardware resources that are dedicated to the sole use of a
> tenant)
> 2) Virtual machine (instance) reservation (when user may ask
> reservation service to provide him working VM not necessary now, but
> also in the future)
Climate is born from the idea of dedicating compute resources to a 
single tenant or user for a certain amount of time, which was not yet 
implemented in Nova: how as an user, can I ask Nova for one compute host 
with certain specs to be exclusively allocated to my needs, starting in 
2 days and being freed in 5 days ?

Albeit the exclusive resource lock can be managed on the Nova side, 
there is currently no possibilities to ensure resource planner.

Of course, and that’s why we think Climate can also stand by its own 
Program, resource reservation can be seen on a more general way : what 
about reserving an Heat stack with its volume and network nested resources ?

> You want to support being able to reserve an instance in the future.
> As a cloud operator how do I take advantage of that information? As a
> cloud consumer, what is the benefit? Today OpenStack supports both
> uses cases, except it can't request an Instance for the future.

Again, that’s not only reserving an instance, but rather a complex mix 
of resources. At the moment, we do provide way to reserve virtual 
instances by shelving/unshelving them at the lease start, but we also 
give possibility to provide dedicated compute hosts. Considering it, the 
logic of resource allocation and scheduling (take the word as resource 
planner, in order not to confuse with Nova’s scheduler concerns) and 
capacity planning is too big to fail under the Compute’s umbrella, as it 
has been agreed within the Summit talks and periodical threads.

 From the user standpoint, there are multiple ways to integrate with 
Climate in order to get Capacity Planning capabilities. As you perhaps 
noticed, the workflow for reserving resources is different from one 
plugin to another. Either we say the user has to explicitly request for 
dedicated resources (using Climate CLI, see dedicate compute hosts 
allocation), or we implicitly integrate resource allocation from the 
Nova API (see virtual instance API hook).

We truly accept our current implementation as a first prototype, where 
scheduling decisions can be improved (possibly thanks to some tight 
integration with a future external Scheduler aaS, hello Gantt), where 
also resource isolation and preemption must also be integrated with 
subprojects (we’re currently seeing how to provision Cinder volumes and 
Neutron routers and nets), but anyway we still think there is a (IMHO 
big) room for resource and capacity management on its own project.

Hoping it's clearer now,
-Sylvain