Patent attributes
Data objects are stored on storage devices, taking into account service level agreements or other quality of service parameters. In one aspect, data objects grouped into storage volumes. In addition, the storage devices are classified into different level storage tiers, where higher level storage tiers have higher performance and lower level storage tiers have lower performance. Ranks for the data objects are calculated, based on both a data usage pattern for the data object (e.g., recency and frequency) and on quality of service (QOS) parameters for the storage volume containing the data object. Examples of QOS parameters include service level agreements, priority, minimum and maximum input/output operations per second. The data objects are then stored on storage devices, based on the data objects' ranks and the storage devices' storage tiers.
