Cloned from launchpad blueprint https://blueprints.launchpad.net/nova/+spec/refresh-quotas-usage. Description: For some reasons*, the quotas usage can be out of sync. When a quota is wrongfully reached, a user cannot launch new VMs anymore. This "refresh" feature allows operators to quickly unblock users without manually running queries against the database or temporarily increase the quota. [*] It seems that there are several root causes and there is no procedure to reproduce bugs. Although these root causes will eventually be identified, we cannot guarantee that some bugs will not occur again. Specification URL (additional information): https://review.openstack.org/#/c/161782