[Ovirt-devel] Questions on the Server Suite UI

[Scott Seago]

Bryan Kearney wrote:
> Hugh O. Brock wrote:
>> On Mon, Nov 17, 2008 at 01:08:19PM -0500, Bryan Kearney wrote:
>>> Hugh O. Brock wrote:
>>>> On Mon, Nov 17, 2008 at 09:38:45AM -0500, Bryan Kearney wrote:
>>>>> Below are a couple of functional question on the UI having 
>>>>> installed it,  and reviewed version .6 of the docs. I realize the 
>>>>> answer may be "in an  upcoming release", but I wanted to at least 
>>>>> throw it out:
>>>> Hi Bryan, thanks for checking out oVirt!
>>>>
>>>>> 1) Can I set quotas at the VM pool level, or are they only 
>>>>> inherited  from the hardware pool?
>>>> Yes -- in fact the VM pool is the main carrier for quotas. The
>>>> hardware pool quota settings merely define a default for VM pools
>>>> created within a hardware pool. I recall a bug one or two releases ago
>>>> however where the "edit quota" link in the details pane for a VM pool
>>>> was either obscured or missing -- I think I even filed the BZ for
>>>> it. I thought it was fixed in the current release but maybe not. I'll
>>>> check on it.
>>>>
>>>>> 2) Are there plans to support moving vm pools between hardware pools?
>>>> I believe we had decided we didn't want to do this, simply because the
>>>> act of moving a VM pool to another hardware pool would imply
>>>> mass-migrating all the VMs there to a hardware pool where they would
>>>> not necessarily be able to run (the hardware pool defines hardware
>>>> compatibility -- e.g. Intel vs. AMD -- and migration boundaries). Can
>>>> you think of a use case we should to support here?
>>> The use case I was thinking was one of quota policy. I could see 
>>> using  high level hardware pools as a means to group VM pools with 
>>> the same  quota and SLA. If a groups is granted a higher or lower 
>>> Quota/SLA then I  would want to move the vm pool to a new hardware 
>>> pool.
>>>
>>
>> Interesting. The more I think about it the more I think we really need
>> to nest VM pools to handle it. Since the VM pool carries things like
>> quota and (eventually) SLA, what you really probably want is to allow
>> VM pools to have VM pool children that are subject to the SLA of the
>> parent... and you want to be able to move a child VM pool from one
>> parent to another. This keeps the hardware pool firmly in the
>> physical-topology-related domain of network and migration boundaries,
>> while tying VM pools more firmly to SLA and chargeback and so on.
>>
>> Scott, what do you think of this?
>
>
> Either that, or you take in a mix-in approach where quota and SLA is 
> provides as an attribute.. not as inheritance from its location in the 
> tree.
>
> -- bk 
Well that's sort of what we have. Quota only inherits from the parent if 
you don't provide one for the VM pool. Assuming we attach SLA to the 
quotas, this would probably be set up in a similar manner. Although 
you'd have additional flexibility with nested VM pools.

Scott