Hey all, I will start the answers :) At OVH, our hard limit is around 1500 hypervisors on a region. It also depends a lot on number of instances (and neutron ports). The effects if we try to go above this number: - load on control plane (db/rabbit) is increasing a lot - "burst" load is hard to manage (e.g. restart of all neutron agent or nova computes is putting a high pressure on control plane) - and of course, failure domain is bigger Note that we dont use cells. We are deploying multiple regions, but this is painful to manage / understand for our clients. We are looking for a solution to unify the regions, but we did not find anything which could fit our needs for now. Cheers, -- Arnaud Morin On 28.01.21 - 14:24, Thierry Carrez wrote:
Hi everyone,
As part of the Large Scale SIG[1] activities, I'd like to quickly poll our community on the following question:
How many compute nodes do you feel comfortable fitting in a single-cluster deployment of OpenStack, before you need to scale it out to multiple regions/cells/.. ?
Obviously this depends on a lot of deployment-dependent factors (type of activity, choice of networking...) so don't overthink it: a rough number is fine :)
[1] https://wiki.openstack.org/wiki/Large_Scale_SIG
Thanks in advance,
-- Thierry Carrez (ttx)