[Users] scheduling storage migration

[Itamar Heim]

On 04/06/2014 06:16 PM, Gilad Chaplik wrote:
> ----- Original Message -----
>> From: "Itamar Heim" <iheim at redhat.com>
>> To: "Jorick Astrego" <j.astrego at netbulae.eu>
>> Cc: "users" <users at ovirt.org>
>> Sent: Friday, April 4, 2014 3:52:01 PM
>> Subject: Re: [Users] scheduling storage migration
>>
>> On 04/04/2014 03:34 PM, Jorick Astrego wrote:
>>>
>>> On Fri, 2014-04-04 at 15:02 +0300, Itamar Heim wrote:
>>>> On 04/04/2014 10:51 AM, Jorick Astrego wrote:
>>>>> Hi,
>>>>>
>>>>> I don't know if it's possible yet but can we schedule the (live) storage
>>>>> migration?
>>>>>
>>>>> It would be awesome to have for example some VM data on SSD storage that
>>>>> migrates to HDD storage when the VM is shutdown. Or have VM's with high
>>>>> IO load during specific times migrate to a high IO storage domain during
>>>>> these hours.
>>>>
>>>> if the VM is down, you can move it, not (live) storage migration.
>>>>>
>>>>> I realize it will generate extra load while migrating but this can be
>>>>> planned for. Maybe the guys from glusterfs could enable storage
>>>>> migration on their side so the migration can execute on the storage
>>>>> server triggered by ovirt, that would be even better performance wise.
>>>>
>>>> in any case, you can script anything with the API...
>>>>
>>>
>>> I was being lazy... So I can use the
>>> http://www.ovirt.org/Features/oVirtSchedulerAPI for this? Or do I have
>>> to hack around with the engine api. I will spend some time diving into it.
>>
>> you can use the scheduler api, but I don't remember it having an event
>> for OnVmStop.
>> you can also use it for a periodic "balancing" call, but for that, you
>> can also just use cron.
>> in either case you will need to do the relevant api calls for moving the
>> disks around. i'd go with the cron approach.
>
> What about a vdsm hook?

you can't move things around not via engine or you will lose the sync 
between them