Abstract: Methods, apparatuses and storage medium associated with ISA bridging with callback, are disclosed. In various embodiments, at least one computer-readable storage medium may include instructions configured to enable a target device with a target ISA, in response to execution of the instructions, to provide an ISA bridging layer to the target device to facilitate a library service to callback a callback function of an application. The library service may be implemented for the target ISA, and the application may be implemented at least partially for a source ISA that may be different from the target ISA. The ISA bridging layer may include a source ISA emulator and a library emulator configured to cooperate to enable the application to call the library service, and the library service to callback the callback function, across the two instruction set architectures. Other embodiments may be disclosed or claimed.

Abstract: Methods, apparatuses and storage medium associated with ISA bridging with callback, are disclosed. In various embodiments, at least one computer-readable storage medium may include instructions configured to enable a target device with a target ISA, in response to execution of the instructions, to provide an ISA bridging layer to the target device to facilitate a library service to callback a callback function of an application. The library service may be implemented for the target ISA, and the application may be implemented at least partially for a source ISA that may be different from the target ISA. The ISA bridging layer may include a source ISA emulator and a library emulator configured to cooperate to enable the application to call the library service, and the library service to callback the callback function, across the two instruction set architectures. Other embodiments may be disclosed or claimed.

Abstract: Monitoring an activity profile for a given row of a database and determining a target database for a given row based on the activity profile of the given row. Identifying any row related to the given row and moving the given row and any row related to the given row into the target database while preserving referential integrity.

Abstract: An intelligent router routes a user request to a storage server that is capable of handling that request natively, without emulation. The request is routed automatically, without any instruction or interaction on the part of the user. The intelligent router includes a storage tank-like computing environment and a set of intelligent routers. The set of intelligent routers appears as a single entity to users by presenting a single network IP address. When the intelligent router receives a request, it examines the protocol type and routes the request to one of the appropriate storage tank clients. The intelligent router does not change the contents of the request message, and thus the storage tank system do not become aware of the existence of the intelligent router. Consequently, any return messages do not need to go through the intelligent router, unless desired.

Abstract: Monitoring an activity profile for a given row of a database and determining a target database for a given row based on the activity profile of the given row. Identifying any row related to the given row and moving the given row and any row related to the given row into the target database while preserving referential integrity.

Abstract: A method for managing data is provided which includes monitoring an activity profile for a given row of a database and determining a target database for a given row based on the activity profile of the given row. The method further includes identifying any row related to the given row and moving the given row and any row related to the given row into the target database while preserving referential integrity.

Abstract: A method and apparatus for visualizing hierarchy data with angular chart are provided wherein the hierarchy data comprises a plurality of levels. The method comprises determining at least one of the plurality levels of the hierarchy data as base levels; visualizing data units in the base levels with the angular chart, wherein each slice of the angular chart corresponds to the data unit in the hierarchy data; and in response to user's operation on the slice of the angular chart, visualizing data units in at least next level of the data unit corresponding to the selected slice. The data units in each level of the hierarchy data can be visualized hierarchically and clearly, even if the hierarchy data has numerous levels and/or data units.

Abstract: A cost-adaptive cache including the ability to dynamically maximize performance in a caching system by preferentially caching data according to the cost of replacing data. The cost adaptive cache includes a partitioned real cache, wherein data is stored in each of the real cache partitions according to its replacement cost. Also, the cost-adaptive cache includes a partitioned phantom cache to provide a directory of information pertaining to blocks of data which do not qualify for inclusion in the real cache. The partitions in the phantom cache correspond to the partitions in the real cache. Moreover, the cost-adaptive cache maximizes performance in a system by preferentially caching data that is more costly to replace. In one embodiment of the system, the cost of replacing a block of data is estimated by the previous cost incurred to fetch that block of data.

Abstract: Stored data can be recovered from a disk array having at least 2n+1 physical disks that are capable of storing n physical disks worth of data when any two disks fail, or when more than two dependent disks fail. Data is stored in data stripes that are divided into n substantially equal-sized strips and are distributed across the n disks. Each data stripe has a corresponding parity strip that is generated by including the data strips in the data stripe only once when the parity strip is generated. The data strips of each data stripe, the copy of each such data strip and the corresponding parity strip are distributed across the disks in such a manner that the data strips of each data stripe, the copy of each such data strip and the corresponding parity strip are each on a respectively different disk of the disk array.

Abstract: A method for reorganizing data in a storage device for improved performance is provided where the device stores data as data units each associated with a sequential address. The method for reorganizing data includes allocating a reorganization region capable of storing N units and grouping the data units into a plurality of extents each having a generally large number of units. The method further includes sorting the extents based on the frequency of request of the units in the extents and copying N most frequently requested units from the sorted extents into the reorganization region while preserving the order of the sorted extents and the order of the sequential addresses of the units in each extent. The method also includes servicing requests for data using data in the reorganization region.

Abstract: A method, apparatus, and article of manufacture provide the ability to maintain cache in a clustered environment. The cache is maintained in both a primary and secondary node. When data is requested, a symbolic list in a cache directory is examined to determine which node's cache contains the requested data. If the symbolic list indicates data is not currently in cache of any node, any node may be used as the secondary node. However, if an original primary node maintains the data in cache, the original primary node is selected as the secondary node. Once a new write I/O operation is performed, the symbolic list is updated to provide. To install a new node, after applying for cluster admission, symbolic information and a modified track list is requested. The modified track list is merged with new symbolic entries and the new node then broadcasts its availability to the cluster.

Abstract: A data storage system and method for reorganizing data to improve the effectiveness of data prefetching and reduce the data seek distance. A data reorganization region is allocated in which data is reorganized to service future requests for data. Sequences of data units that have been repeatedly requested are determined from a request stream, preferably using a graph where each vertex of the graph represents a requested data unit and each edge represents that a destination unit is requested shortly after a source unit the frequency of this occurrence. The most frequently requested data units are also determined from the request stream. The determined data is copied into the reorganization region and reorganized according to the determined sequences and most frequently requested units. The reorganized data might then be used to service future requests for data.

Abstract: The present invention discloses a method, apparatus, and article of manufacture for implementing a locking structure for supporting parity protection in a RAID clustered environment. When updating parity, the parity is locked so that other nodes cannot access or modify the parity. Accordingly, the parity is locked, read, generated, written, and unlocked by a node. An enhanced protocal may combine the lock and read functions and the write and unlock functions. Further, the SCSI RESERVE and RELEASE commands may be utlized to lock/unlock the parity data. By locking the parity in this maner, overhead is mininized and does not increase as the number of nodes increases.

Abstract: A computer-implemented method for clustering related data pages in close physical proximity to each other on a magnetic disk drive or other storage device. The method includes identifying relationships between the pages, with the relationships being established not simply by time of page access, but rather by user access patterns. The pages are clustered based on the relationships. To undertake the clustering, the pages and references can be represented and analyzed as respective vertices and edges in edge graphs.

Abstract: An intelligent router routes a user request to a storage server that is capable of handling that request natively, without emulation. The request is routed automatically, without any instruction or interaction on the part of the user. The intelligent router includes a storage tank-like computing environment and a set of intelligent routers. The set of intelligent routers appears as a single entity to users by presenting a single network IP address. When the intelligent router receives a request, it examines the protocol type and routes the request to one of the appropriate storage tank clients. The intelligent router does not change the contents of the request message, and thus the storage tank system do not become aware of the existence of the intelligent router. Consequently, any return messages do not need to go through the intelligent router, unless desired.

Abstract: A data storage system and method for reorganizing data to improve the effectiveness of data prefetching and reduce the data seek distance. A data reorganization region is allocated in which data is reorganized to service future requests for data. Sequences of data units that have been repeatedly requested are determined from a request stream, preferably using a graph where each vertex of the graph represents a requested data unit and each edge represents that a destination unit is requested shortly after a source unit the frequency of this occurrence. The most frequently requested data units are also determined from the request stream. The determined data is copied into the reorganization region and reorganized according to the determined sequences and most frequently requested units. The reorganized data might then be used to service future requests for data.

Abstract: A method of writing to cache in a clustered environment. A first node in a storage cluster receives a request to write data from a user application. The first node determines if the data is owned by a remote node. If the data is owned by a remote node, the data in the remote node may be invalidated, if necessary. Such invalidation may not be necessary if a global cache directory is utilized. Thereafter, the data is written in a cache of the first node. Additionally, the data is written in a cache of a partner node of the first node. Confirmation of the cache write in the partner node is then received in the first node.

Abstract: The present invention is system and method for determining information that is to be prefetched in a multi-stream environment which can detect sequential streams from among the aggregate reference stream and yet requires relatively little memory to operate, which is uniquely adapted for use in a multi-stream environment, in which multiple data accessing streams are performing sequential accesses to information independently of each other. A reference address referencing stored information is received. A matching run is found. A count corresponding to the run is updated. If the count exceeds a predetermined threshold, an amount of information to prefetch is determined. If a predetermined fraction of the determined amount of information to prefetch must still be retrieved, the determined amount of information is retrieved. A matching run may be found by searching a stack comprising a plurality of entries to find an entry corresponding to the reference address.

Abstract: A hot pluggable system includes an interlock between a component fail detect module and a component lock mechanism, such that the component is locked in place when it operates properly and is automatically released to permit a person to remove the component from the system when the component fails. In this way, the risk of human errors in removing the wrong component is reduced.

Abstract: A method, apparatus, article of manufacture, and a memory structure for an internode network. Nodes are active-active using commodity hardware so that the system can perform I/O together between any number of nodes, and data can be located on any given node. A single modified image is configured to maintain recent and updated data. At least one failure can occur (and be corrected) in the nodes before data is written to disk. A history of access points is kept in a cache directory, and it is assumed that the nodes most frequently accessed in the past are likely to be the most frequently accessed in the near future. One or more embodiments of the invention move this data to where it will likely be needed. This means that data is delivered to hosts quickly, as is required in high volume enterprise web environments. The symbolic list in the cache directory provides a history of the nodes that have previously performed I/O operations.