Described are techniques for use in determining a dynamic mirror service policy (DMSP) for a plurality of mirror devices. The DMSP determines which of the plurality of mirror devices services I/O operations associated with a logical volume (LV), such as a read operation, at a particular point in time. The particular DMSP may subsequently be recalculated using device statistics from a different time interval. Part of determining a DMSP includes using device statistics to determine the activity level of each LV. The activity levels of multiple LVs may be combined to determine the activity level associated with a particular mirror device. A mirror device is selected if it has the minimum activity of all the plurality of mirror devices. Seek minimization processing is performed to minimize the distance between LVs stored on a single mirror device. Parameters used in connection with determining a DMSP may be stored in a configuration file and may be dynamically modified. Techniques described may also be used in an embodiment having a static MSP.

A computer-implemented method for automatically configuring a data-storage system includes receiving a specification of mass-storage elements to be incorporated into the data-storage system and identifying installed resources of the data-storage system that are available for sharing among the mass-storage elements. The mass-storage elements are then mapped to a subset of the installed resources. This subset is selected to equalize the additional load on the installed resources that arise as a result of incorporating the additional mass-storage elements into the data-storage system.

A database system for storing table data as divided in a plurality of storages has a processing request acceptance section and an execution section which, at the time of rebalancing already stored data in response to addition of a storage, can execute inquiry operations concurrently. The system determines data to be moved from existing storages to the additional storage. When search, update and delete processing requests are issued during execution of the rebalance operation of copying the data to the additional storage and deleting the original data, both the DBMS acceptance section and DBMS executor section execute the operation corresponding to the requests. When an insert processing request is issued, the system determines a data insert destination on the basis of contents of a step of dividing the data from the existing storages to the additional storage.

A system and method for enhancing read performance of at least one storage array using a spare storage array of coupled spare drives, wherein the at least one storage array includes coupled drives configured to store data according to a redundant storage methodology. Data is copied from at least one logical disk of data from the at least one storage array onto the spare storage array and read from the least busy array of the at least one storage array or the spare storage array.

A storage system comprises a plurality of storage arrays configurable into a plurality of storage device groups, a plurality of controllers selectively coupled to ones of the storage arrays, a network fabric arranged as a linkage of multiple sets of associated controllers and storage devices, and a processor. The processor is capable of associating the plurality of storage device groups among controllers based on a distribution of performance demand according to controller processor utilization of the individual storage device groups and bandwidth utilization pro-ratable among storage device groups within a set.