[ovirt-users] async vm start (python)

[Giulio Casella]

Thanks Juan,
this clearify a lot of things. So starting a VM is always a synchronous 
task in the backend, isn't it?
But in some condition (heavy load of hypervisors) this task takes long 
time (up to 20/30 seconds), not really suitable for sync tasks.
Maybe I should submit a feature request...

Ciao,
gc


Il 14/10/2014 16:53, Juan Hernandez ha scritto:
> On 10/14/2014 01:04 PM, Giulio Casella wrote:
>> Hi everybody,
>> I'm trying to start a VM (using python sdk) asynchronously, but I obtain
>> synchronous behaviour.
>> The engine is RHEV-M version 3.4.1-0.31.el6ev.
>> Here a snippet of code:
>>
>> ---------------------------------------------------------
>> myvm = api.vms.get(name="VMNAME")
>> retval = myvm.start(params.Action(async=True))
>> print ParseHelper.toXml(retval)
>> ---------------------------------------------------------
>>
>> and this is what I get (retval):
>>
>> ---------------------------------------------------------
>> <action>
>>       <async>true</async>
>>       <vm href="/api/vms/5aa66e96-5fdd-4562-9c7d-ae6f88e6805d"
>> id="5aa66e96-5fdd-4562-9c7d-ae6f88e6805d">
>> [...cut..]
>>       </vm>
>>       <job href="/api/jobs/5c2326c7-f25c-432f-8848-c94e80dd173b"
>> id="5c2326c7-f25c-432f-8848-c94e80dd173b"/>
>>       <status>
>>           <state>complete</state>
>>       </status>
>> </action>
>> ---------------------------------------------------------
>>
>> status of task is always "complete" and the operation take some time,
>> few seconds to some tens of seconds (sync behaviour).
>>
>> Any ideas?
>>
>> Thanks in advance,
>> Giulio
>>
>
> The "async" parameter that you are passing to the REST API is only a
> hint. It means that *if* the action performed by the backend has
> associated async tasks then the REST API will not wait for them to
> finish. In this particular case, the action performed by the backend
> doesn't have async tasks, so the parameter is just ignored.
>

-- 
Giulio Casella                                    giulio at di.unimi.it
System and network manager
Computer Science Dept. - University of Milano