On 4/19/2019 4:38 PM, melanie witt wrote:
I agree it sounds like your overcommit settings are not being honored. Placement will filter hosts taking overcommit into account, and if it doesn't have the values you set, then it will return more hosts than the RamFilter would filter, causing the difference in behavior.
To debug this further, you need to start looking at what values placement has for the allocation ratios. You can do this by installing the osc-placement plugin [1] for the openstackclient. Once installed, you can do 'openstack resource provider inventory list <compute host UUID>' to see what allocation ratios are being used on a given compute host. If they're not 1.0, that would explain why it's returning too many hosts. If that's the case, next step would be trying to figure out why the values you're setting in nova.conf on the compute host (I assume you made sure to restart nova-compute after setting) are not being transferred to placement like they should be.
Some more background on how placement is involved here: https://docs.openstack.org/nova/latest/admin/configuration/schedulers.html#a... https://specs.openstack.org/openstack/nova-specs/specs/stein/implemented/ini... -- Thanks, Matt