Abstract: A system is provided to support dynamically changeable virtual mapping schemes in a data processing system. The present invention separates processing of data unit requirements from the selection of which storage subsystems to use for storage by using a storage methodologies inventory. A stored data management subsystem contains one or more hosts. A plurality of data storage elements is functionally coupled to the one or more hosts. The plurality of data storage elements is organized using a plurality of layers of mapping tables. The plurality of layers of mapping tables provides unique identification of location of the data such that individual data entries in a mapping table is variable and self-defining with respect to the amount of data managed.

Abstract: A system is provided to support dynamically changeable virtual mapping schemes in a data processing system. The present invention separates processing of data unit requirements from the selection of which storage subsystems to use for storage by using a storage methodologies inventory. A stored data management subsystem contains one or more hosts. A plurality of data storage elements is functionally coupled to the one or more hosts. The plurality of data storage elements is organized using a plurality of layers of mapping tables. The plurality of layers of mapping tables provides unique identification of location of the data such that individual data entries in a mapping table is variable and self-defining with respect to the amount of data managed.

Abstract: A method and apparatus for managing power sequencing in a data storage system. The turn-on or spin-up sequence for the media drives in an array of media drives is selectively controlled such that the overall rush current is reduced. The individual drive components are characterized to determine a power profile for each such component. A closed-loop process is then used to manage and reduce peak power requirements when starting up or spinning up an array of media drives using the drive profiles. The media drives can also be organized as a plurality of sets of drives, and a power profile for each set of drives is used to manage and reduce peak power requirements.

Abstract: A method, computer program product, and data processing system for continuously writing new data to a redundant array of independent storage devices without interrupting the writing of new data to the array to reconstruct missing data from a failed device or failed media is disclosed. A fault-tolerance scheme using multiple independent parity values is used to record data to the array. In the event that one of the volumes in the array fails, the remaining volumes continue being written to, but with fewer data or parity values being employed. The failed volume can then be reconstructed following the completion of writing the media set currently being written.

Abstract: The present invention provides a flexible storage system through the use of portable, removable canisters holding multiple storage subsystems.

Abstract: A system and method are disclosed for providing an enhanced snapshot copy pointer. A data element is stored in a first storage subsystem in the data processing system. A first pointer is created in a pointer table in the first storage subsystem. The first pointer includes an address of the data element. A second pointer is created in the pointer table in the first storage subsystem. The second pointer includes an address of the first pointer.

Abstract: A system and method of recognizing resources of a computer comprising a system serial number and a broken hardware unit comprising a non-volatile memory unit and enablement definition data relating to functions of the broken hardware unit, wherein the method comprises starting the computer; entering a serial number in a read/write non-volatile memory field of the non-volatile memory unit; reading the read/write non-volatile memory field; and matching the serial number of the read/write non-volatile memory field with the system serial number. The method may further comprise detecting failure of the broken hardware unit after the starting of the computer. Preferably, a reading that the serial number of the read/write non-volatile memory field matches with the system serial number permits acceptance of the enablement definition data of the broken hardware unit.

Abstract: A method, system and program for generating parity in a data storage system are provided. The invention comprises organizing an incoming data block into a specified number of data stripes and cascading the data stripes into a parity creation mechanism. The parity creation mechanism creates a specified number of parity stripes based on the data stripes, wherein the number of parity stripes is independent of the size of the data block. The parity creation mechanism can operate offline to reconstruct lost data stripes and parity stripes without using critical system resources, wherein the number of devices required for stripe reconstruction is less than the combined number of data stripes and parity stripes.

Abstract: A mechanism is provided for storing self-defining data and mapping elements with either a fixed set of allowed structures or types or with the structures and types determined by rules. Recovery is enhanced by the use of backward and forward pointers between data and mapping elements for the data elements in the order written by the management algorithm. Recovery is also enhanced by the use of companion pointers with metadata. The companion pointers may include pointers to data or mapping elements that are part of the same structural grouping. The metadata may describe the structural grouping. The metadata may also include pointers to the previous and/or next versions of the same elements. Recovery of the data and/or mapping structures is achieved by the reverse application of the management algorithm.

Abstract: A system and method for configuring expandable buses wherein a host supports a plurality of expandable buses are provided. A plurality of devices are arranged to form a plurality of groups. Each group forms a chain of devices on an expandable bus. Each chain includes an input connector. The chains are configured such that connecting an expandable bus of the host to the input connector for a particular chain causes that particular chain to be directly connected to that particular expandable bus of the host. The absence of connecting any expandable bus of the host to the input connector for a particular chain causes that particular chain to be directly connected to a different chain so as to be indirectly connected to one of the expandable buses of the host. In another embodiment, the connections to an expandible bus of the host must be consistent with a predetermined connection logic.

Abstract: A data storage system for storing data for a host processor includes physical data storage devices each having data storage attributes and an outboard storage manager. The outboard storage manager is operable with the physical data storage devices for presenting to the host processor a virtual data storage image having a desired data storage attribute for a particular data storage application by organizing the physical data storage devices in an arrangement suitable for providing the desired data storage attribute irrespective of the data storage attributes of the physical data storage devices such that the combined physical data storage device arrangement emulates the virtual data storage image. The outboard storage manager is operable to transfer data between the host processor and the organized physical data storage device arrangement via the virtual data storage image.

Abstract: An automated storage system includes a media storage facility, which may take the form of an automated storage library or shelf system. The media storage facility includes a plurality of individual medium slots and a plurality of superset slots. The facility further includes at least one mechanism for accessing individual media and at least one mechanism for accessing supersets of media. Individual media located in a superset remain accessible on an individual basis in addition to being accessible as part of the corresponding superset.

Abstract: An independent distributed metadata system and method are provided. With the system and method, metadata, which is associated with data at one or more data source locations, may be distributed independently of the data and manipulated independently to generate various computing environments. For example, a user may obtain a copy of metadata and use this metadata, at a remote location from the data source location, to create a computing environment, such as a virtual server, web page or the like. The computing environment created by the user consists entirely of metadata and does not include the actual data to which the metadata is associated. In this way, different users may have independent copies of the metadata and use it to generate their own computing environments without having to have access to the actual data.

Abstract: A guide tab and a multiple member slide incorporating such guide tab are provided. The guide tab is coupled to one slide member of the slide. When actuated, the guide tab activates a latch allowing another slide member of the slide to decouple from the slide.

Abstract: A method for scaling resources according to workload among virtual servers running on a mainframe computer is provided. The invention comprises monitoring the number of service requests received by a cluster of virtual servers and determining if the service requests exceed a specified service limit for the servers. If the number of service requests exceeds the specified service limit, a new virtual server is automatically deployed by a software solution. This additional virtual server performs identical services as the other virtual servers in the cluster. This process is repeated until there are a sufficient number of servers to handle the workload. Service requests are then allocated among the cluster of virtual servers, until the number of requests falls below a certain threshold, at which point the extra servers are automatically deactivated.

Abstract: An apparatus and method for implementing structure level pointers in a data storage system are provided. With the apparatus and method, a compound pointer system is provided in which fixed level pointers are augmented with associated pointers to metadata describing lower level structures. The companion metadata describes these lower level structures in a manner independent of the actual data stored within the lower level structures. With such an enhanced compound pointer system, an instant copy mechanism can process the pointers to the underlying structures and take instant copies of much finer detail. This allows individual records of data to be represented by the pointer system without having the overhead of carrying a pointer to all the individual records. The instant copy mechanism not only copies the fixed level pointers, but resolves the companion pointers to individual subsets of a general granularity for the instances of the instant copy domains.

Abstract: A method, system and program for generating parity in a data storage system are provided. The invention comprises organizing an incoming data block into a specified number of data stripes and cascading the data stripes into a parity creation mechanism. The parity creation mechanism creates a specified number of parity stripes based on the data stripes, wherein the number of parity stripes is independent of the size of the data block. The parity creation mechanism can operate offline to reconstruct lost data stripes and parity stripes without using critical system resources, wherein the number of devices required for stripe reconstruction is less than the combined number of data stripes and parity stripes.

Abstract: A method and system for sharing data and interrogating data include establishing a level of trust between mutually mistrusting entities so that data may be shared therebetween based on the level of trust. The method and system include interrogating data provided from one of the entities to the other entity without the receiving entity having complete access to the data associated therewith.

Abstract: A drawer slide for coupling a drawer to a cabinet is provided. A drawer rail is C-shaped. An intermediate rail is partially housed within the drawer rail and includes a web and first and second legs which are connected to the web by two folds in the material used to form the intermediate rail. A flange extends from the first leg toward the second leg. Bearings housed in bearing cages placed between the rails allow sliding movement therebetween. A cabinet rail is partially housed within the intermediate rail and includes an upright wall and a flange extending away from the upright wall and toward the first leg. Ball and roller bearings housed in bearing cages couple the flanges. Grooves in the flanges are engaged by the ball bearings. Roller bearings housed in bearing cages couple the web of the intermediate rail and the flange of the cabinet rail, as well as the second leg of the intermediate rail and the upright wall of the cabinet rail.