--- features: - | A new setting ``OPENSTACK_USE_SIMPLE_TENANT_USAGE`` was introduced as a replacement of ``SimpleTenantUsage`` in the deprecated ``OPENSTACK_NOVA_EXTENSIONS_BLACKLIST`` setting. This new setting controls whether ``SimpleTenantUsage`` nova API is used in the usage overview. According to feedbacks to the horizon team, the usage of ``SimpleTenantUsage`` can cause performance issues in the nova API in larger deployments. Try to set this to ``False`` for such cases. upgrade: - | Considering the deprecation of ``OPENSTACK_NOVA_EXTENSIONS_BLACKLIST``, set a new setting ``OPENSTACK_USE_SIMPLE_TENANT_USAGE`` to ``False`` if you specify ``SimpleTenantUsage`` in ``OPENSTACK_USE_SIMPLE_TENANT_USAGE``