Open Stack

On 07/29/2016 02:29 PM, Jay Pipes wrote:
> On 07/28/2016 09:02 PM, Devananda van der Veen wrote:
>> On 07/28/2016 05:40 PM, Brad Morgan wrote:
>>> I'd like to solicit some advice about potentially implementing
>>> get_all_bw_counters() in the Ironic virt driver.
>>>
>>> https://github.com/openstack/nova/blob/master/nova/virt/driver.py#L438
>>> Example Implementation:
>>> https://github.com/openstack/nova/blob/master/nova/virt/xenapi/driver.py#L320
>>>
>>>
>>> I'm ignoring the obvious question about how this data will actually be
>>> collected/fetched as that's probably it's own topic (involving
>>> neutron), but I
>>> have a few questions about the Nova -> Ironic interaction:
>>>
>>> Nova
>>> * Is get_all_bw_counters() going to stick around for the foreseeable
>>> future? If
>>> not, what (if anything) is the replacement?
> 
> I don't think Nova should be in the business of monitoring *any*
> transient metrics at all.
> 
> There are many tools out there -- Nagios, collectd, HEKA, Snap, gnocchi,
> monasca just to name a few -- that can do this work.
> 
> What action is taken if some threshold is reached is entirely
> deployment-dependent and not something that Nova should care about. Nova
> should just expose an API for other services to use to control the guest
> instances under its management, nothing more.

More importantly... *only* xenapi driver implements this, and it's not
exposed over the API. In reality that part of the virt driver layer
should probably be removed.

Like jay said, there are better tools for collecting this than Nova.

	-Sean

-- 
Sean Dague
http://dague.net