Abstract: Parity updates are performed in an efficient manner after data is modified on removable media in a RAID or RAIL array, within or outside the array, without requiring that all of the data on all of media in a parity group be read. Instead, a list is maintained identifying those blocks of data were which modified on the media. Only the corresponding blocks on the remaining media in the parity group are read to calculate the new parity. Alternatively, a list can be maintained identifying the bits which were changed on the media. Consequently, only the corresponding bits of the parity block(s) need be changed.

Abstract: A system for optimizing the position and use of cartridges of machine-readable data storage media in an automated super library. The invention is implemented in a super library that includes a main library bin with a plurality of cartridge slots, a picker, and multiple small libraries, where each small library has a small library bin with multiple slots, a picker, and at least one data drive. Mount queue times are estimated for each small library, and a main library picker is selectively operated to transfer cartridges between the small libraries based on the estimated mount queue times. This provides expedited access of the cartridges at the small libraries. The host processor maintains requests for such inter-library transfers in a main picker queue, for processing by the main picker. When each small library has a non-empty mount queue, the main picker processes small libraries' cartridge transfer requests by efficiently distributing cartridges along the small libraries.

Abstract: In an data storage system, a volume transform filter is employed in conjunction with a RAID array manager to maintain logical volumes entirely on corresponding physical data storage volumes while maintaining parity information on a dedicated parity storage volume. This is achieved by modifying data access commands received from a host such that forwarding the modified commands to the RAID array manager in effect "tricks" the RAID array manager into maintaining the logical volumes without striping. This system provides data allocation with standalone data and parity storage volumes, which are easily exportable for convenient use in data storage libraries.

Abstract: A system for enabling expanded instruction sets, applications, data and parameters to be downloaded from one processor to another so that processors ordinarily intended for specific tasks can run other tasks without having an expanded instruction set and application code specifically developed or always resident. In an exemplary embodiment, four types of extended commands are issued by the system processor to the peripheral processor in which a command table is built to point to interpretable images resident therein. The interpretable image is downloaded by a first command and contains the executable code and parameters needed to perform the downloaded task. A second command is issued to execute the interpretable image and may include additional data. A third command is provided to delete previously downloaded interpretable images, and a fourth command is provided to enable the system processor to query other processors for resident interpretable images.