[one-users] Resource Allocation Policy

[Ruben S. Montero]

Hi,
The ability to specify a default rank is in our roadmap [1], although
this one did not make it for release 3.0.
Basically, the scheduler works as follows.

1.- Builds a list of suitable hosts for a VM (checking REQUIREMENTS,
and the dynamic capacity of the host)

2.- Applies scheduling policies, that assigns each host a priority for
the VM (currently only a rank policy is implemented)

3.- Sorts the prioritized list of hosts.

So if there is no rank each hosts gets 0, the array is sorted (sort
from STL algorithm) and the first one is picked.  The standard says
that elements that would compare equal to each other are not
guaranteed to keep their original relative order.

I would say that in most cases it should be the first host with enough
capacity, but it depends on the output of sort.

Cheers

Ruben


[1] http://dev.opennebula.org/issues/360

On Wed, Jun 22, 2011 at 2:45 PM, fanttazio <fanttazio at gmail.com> wrote:
>
> Hi Vivek,
>
> I read the Doc. but my question is if I do not have any REQUIREMENT attribute and RANK expression in VM template and I have for example three identical hosts in everything how ONE chooses a host for VM?
>
> Regards
> Fanttazio
> On Wed, Jun 22, 2011 at 10:37 AM, Vivek Shrivastava <shrivastava.vivex at gmail.com> wrote:
>>
>> Hi fanttazio,
>>
>> Please go through :-- http://opennebula.org/documentation:rel2.2:schg
>>
>>
>> On Tue, Jun 21, 2011 at 7:15 PM, fanttazio <fanttazio at gmail.com> wrote:
>>>
>>> If in VM's template there is no requirement specification and there are more than one host to run the VM in them, on what basis ONE chooses a host to deploy the VM on that? what is the default policy for resource allocation?
>>> _______________________________________________
>>> Users mailing list
>>> Users at lists.opennebula.org
>>> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>>>
>>
>>
>>
>> --
>> Regards,
>>
>> Vivek Shrivastava,
>>
>
>
> _______________________________________________
> Users mailing list
> Users at lists.opennebula.org
> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>



--
Dr. Ruben Santiago Montero
Associate Professor (Profesor Titular), Complutense University of Madrid

URL: http://dsa-research.org/doku.php?id=people:ruben
Weblog: http://blog.dsa-research.org/?author=7