Methods of data leveling in a virtualized storage system are described. In one implementation, the method comprises detecting an event that changes the eligible storage capacity of a storage system, and, in response to the event: determining a disk critical ratio for each disk in a group of disks in the storage system; determining an RSS critical ratio for a plurality of RSSs in the storage system; and moving data in the storage system in accordance with at least one of the RSS critical ratio and the disk critical ratio.