On 5/23/2019 11:50 AM, Matt Riedemann wrote: > As an aside, I now realize we have a nasty performance regression since > Stein [1] when listing servers with details concerning this host_status > field. The code used to rely on this method [2] to cache the host status > information per host when iterating over a list of instances but now it > fetches it per host per instance in the view builder [3]. Granted by > default policy this would only affect performance for an admin, but if > I'm an admin listing 1000 servers across all tenants using "nova list > --all-tenants" (which is going to use a microversion high enough to hit > this) it could be a noticeable slow down compared to before Stein. I'll > open a bug. > > [1] https://review.opendev.org/#/c/584590/ > [2] > https://github.com/openstack/nova/blob/c7e9e667426a6d88d396a59cb40d30763a3265f9/nova/compute/api.py#L4926 > > [3] > https://github.com/openstack/nova/blob/c7e9e667426a6d88d396a59cb40d30763a3265f9/nova/api/openstack/compute/views/servers.py#L325 https://bugs.launchpad.net/nova/+bug/1830260 -- Thanks, Matt