Abstract: Methods and systems are described comprising a plurality of nodes each comprising at least one processor and at least one storage device providing storage for the system along with an interconnect configured to establish connections between pairs of nodes. The nodes may be configured (e.g. programmed) to determine from a file identifier that identifies a particular file that a node desires to access, which of the plurality of nodes stores the desired file. The interconnect may then establish a connection between the node and the node storing the file to permit the node desiring access to access the file (e.g., read or write the file). Further, the system comprising the plurality of nodes (e.g., a cluster computing architecture) may be balanced or nearly balanced.

Abstract: In a digital data processing system having a memory component, a structure and method for managing available memory resources. Free pointers to respective free memory blocks are stored in memory blocks maintained as a linked list. In a system having a hierarchically-organized memory component, a small number of the free pointers are maintained at a relatively higher performance level of the memory and the balance of the free pointers are maintained at a relatively lower performance level of the memory.

Abstract: A method of managing segments in a distributed-file system implemented by a plurality of file servers includes determining a segment of the distributed-file system controlled by a first file server for which control is to be migrated, selecting a second file server, that is different from the first file server, to take control of the segment, and moving control of the segment from the first file server to the second file server.

Abstract: A data storage system receives sets of the revisions such that each set of revisions changes the dataset from one consistent state to another. Each set of revisions is processed in a write-selected phase followed by a read-selected phase. In the write-selected phase, the revisions in each set are written to a buffer and processed to produce a directory of the set of revisions. In the read-selected phase, the revisions are read from the buffer and integrated into the dataset. When one set of revisions is in the read-selected phase, the next set of revisions is in the write-selected phase.

Abstract: In a digital data processing system having a memory component, a structure and method for managing available memory resources. Free pointers to respective free memory blocks are stored in memory blocks maintained as a linked list. In a system having a hierarchically-organized memory component, a small number of the free pointers are maintained at a relatively higher performance level of the memory and the balance of the free pointers are maintained at a relatively lower performance level of the memory.

Abstract: To accelerate searching of large file system directories, hashing information for a selected directory is compiled and retained in random access memory prior to a need for access to the directory to satisfy a file access request from an application. No change in the on-disk file system representation is required, nor is there any need for nonvolatile storage of the hashing information. If memory is scarce, the hashing information can be incomplete yet give hints for searching the most-recently-accessed directory entries. In a preferred implementation, the hashing information for a directory includes a hash table for searching for names of objects such as files, subdirectories or links in the directory, and a hash table for searching for free space in the directory.