Open Stack

Belmiro/Surya,

I'm trying to follow up on something Belmiro mentioned at the summit 
before I forget about it.

CERN sets this value low:

https://docs.openstack.org/nova/latest/configuration/config.html#scheduler.max_placement_results

And as a result, when disabling nova-computes during maintenance, you 
can fail during scheduling because placement only returns resource 
providers for disabled computes.

I believe Dan and I kicked around some ideas on how we could deal with 
this, like either via a periodic in the compute service or when the 
compute service is disabled in the API, we would set the 'reserved' 
inventory value equal to the total to take those computes out of 
scheduling. I think Belmiro said this is what CERN is doing today as a 
workaround?

For the latter solution, I don't know if we'd proxy that change directly 
from nova-api to placement, or make an RPC cast/call to nova-compute to 
do it, but that's an implementation detail.

I mostly just want to make sure we get a bug reported for this so we 
don't lose track of it. Can one of you open a bug with your scenario and 
current workaround?

-- 

Thanks,

Matt