Abstract: A method for streaming content striped in RAID 5 format from an array of disk drives to subscribers to minimize disruptive service from a disk drive failure. The method includes accessing content data on an extent-by-extent basis from a plurality of disk drives in an array and streams the content data to the subscribers on an extent-by-extent basis, sequentially, from the plurality of disk drives. Upon detection of an actual disk drive failure the method transitions to a stream regeneration mode of operation, which includes reading the content data substantially simultaneously from all extents in a parity group and regenerating a failed portion of the content data from a failed extent in the parity group corresponding to the failed disk drive. The content data in the parity group is streamed to the subscribers, extent-by-extent, immediately following the regenerating of the content data from the failed extent in the parity group.

Abstract: A queuing architecture and method for scheduling disk drive access requests in a video server. The queuing architecture employs at least two access request queues for each disk drive within a disk drive array, and a queue selector for selecting the first and second queues. The first queue is for disk access requests by steady-state users requesting new data streams who are currently viewing a program from the video server. The second queue is for all other types of disk access requests, including requests by new users, requests for loading content, disk maintenance, meta-data synchronizing, and the like. Steady-state disk access requests are serviced in order of ascending time deadlines. The queue selector gives highest priority to requests in the first queue, and requests from the second queue are serviced only upon a guarantee that all of the steady-state requests in the first queue will meet their time deadlines in the worst case access times for the disk drives.

Abstract: A queuing architecture and method for scheduling disk drive access requests in a video server. The queuing architecture employs a controlled admission policy that determines how a new user is assigned to a specific disk drive in a disk drive array.

Abstract: A method of data management for efficiently storing and retrieving data in response to user access requests.

Abstract: A storage server for efficiently retrieving data from a plurality of disks in response to user access requests. The server comprises a plurality of processors coupled to disjoint subsets of disks, and a custom non-blocking packet switch for routing data from the processors to users. By tightly coupling the processors to disks and employing an application-specific switch, congestion and disk scheduling bottlenecks are minimized. By making efficient use of bandwidth, the architecture is also capable of receiving real-time data streams from a remote source and distributing these data streams to requesting users. The architecture is particularly well suited to video-on-demand systems in which a video server stores a library of movies and users submit requests to view particular movies.

Abstract: A method of defining extent for storing a plurality data streams having different bit rates. The method calculates the size of the extent for a given data stream then periodically inserts at least one null packet into the extents to enable any bit rate to be able to be stored using a fixed extent size for the stream.

Abstract: A storage server for efficiently retrieving data from a plurality of disks in response to user access requests. The server comprises a plurality of processors coupled to disjoint subsets of disks, and a custom non-blocking packet switch for routing data from the processors to users. By tightly coupling the processors to disks and employing an application-specific switch, congestion and disk scheduling bottlenecks are minimized. By making efficient use of bandwidth, the architecture is also capable of receiving real-time data streams from a remote source and distributing these data streams to requesting users. The architecture is particularly well suited to video-on-demand systems in which a video server stores a library of movies and users submit requests to view particular movies.

Abstract: A method of defining extent for storing a plurality data streams having different bit rates. The method calculates the size of the extent for a given data stream then periodically inserts at least one null packet into the extents to enable any bit rate to be able to be stored using a fixed extent size for the stream.

Abstract: A queuing architecture and method for scheduling disk drive access requests in a video server. The queuing architecture employs at least two access request queues for each disk drive within a disk drive array. The first queue is for disk access requests by steady-state users who are currently viewing a program from the video server. The second queue is for all other types of access requests including disk access requests by users who wish to begin viewing a program, content loading, meta-data syncing and the like. The method maintains time deadlines for steady-state disk access requests and services these requests in order of ascending deadlines. Requests from the second queue are serviced only if it can be guaranteed that all of the steady-state requests in the first queue will meet their time deadlines in the worst case access time for the disk drive. By taking advantage of the variability of disk seek and transfer times, the method improves the effective disk bandwidth of the video server.

Abstract: An interactive information distribution system includes service provider equipment for generating an information stream that is coupled to an information channel and transmitted to subscriber equipment. The service provider also generates a command signal that is coupled to a command channel and transmitted to the subscriber equipment. The service provider also receives information manipulation requests from the subscriber via a back channel. A communication network supporting the information channel, command channel and back channel is coupled between the service provider equipment and the subscriber equipment.

Abstract: An interactive information distribution system includes service provider equipment for generating an information stream that is coupled to an information channel and transmitted to subscriber equipment. The service provider also generates a command signal that is coupled to a command channel and transmitted to the subscriber equipment. The service provider also receives information manipulation requests from the subscriber via a back channel. A communication network supporting the information channel, command channel and back channel is coupled between the service provider equipment and the subscriber equipment.

Abstract: A method of data management for efficiently storing and retrieving data in response to user access requests. The architecture comprises a plurality of disk drives over which data is distributed, and a plurality of processors, each of which is assigned to a subset of the disk drives in a modular fashion. The server architecture employs dynamic data management methods and load-balancing methods to assign user requests to processors. The modular server architecture, in combination with the dynamic data management and load balancing methods, provides both good performance (i.e., low expected-case access times and high disk bandwidth), and fault-tolerance. The architecture is particularly well suited to video-on-demand systems in which a video server stores a library of movies and users submit requests to view particular programs.

Abstract: A multiple user data storage, retrieval and distribution system containing a parallel processing computer system that forms a digital information server. The server contains a plurality of parallel processors each connected to a information storage device. The user data is stored in a distributed manner amongst the information storage devices. The distribution system dynamically allocates the users to the system based upon the user's requested operating mode. As such, during successive user service periods, all the users are supplied their requested data. The system also provides error detection and correction for the data requested by the users. Furthermore, additional data can be added to the information storage devices during each service period and select information storage devices can be recalibrated without affecting system operation.

Abstract: A method for allocating multiple users to a multiple user data distribution system. More specifically, a data retrieval method for dynamically allocating multiple users to a plurality of parallel processors each connected to an information storage device in a multiple user distribution system. The method allocates each user to at least one processor. The allocated processor represents a slot within a service period. The service period comprises a plurality of slots such that within a given slot an allocated user accesses a subset of information storage devices to supply data to the user. The users are dynamically allocated to the slots in a service period such that the specific time at which each user is serviced and the subset of information storage devices that services them varies from service period to service period. However, each user is serviced during each service period.

Abstract: An advanced massively parallel computer having a plurality of processor subsystems, where each processor subsystem is coupled to a secondary storage device (e.g., disk drive) through a secondary storage interface. The computer contains an input data bus for supplying data to the processor subsystem, an interprocessor communications bus for communicating data and instructions between processor subsystems, and an instruction bus for supplying instructions to the processor subsystems to facilitate data manipulation by each of the processor subsystems.

Abstract: A multiple user data storage, retrieval and distribution system containing a parallel processing computer system that forms a digital information server. The server contains a plurality of parallel processors each connected to a information storage device. The user data is stored in a distributed manner amongst the information storage devices. The distribution system dynamically allocates the users to the system based upon the user's requested operating mode. As such, during successive user service periods, all the users are supplied their requested data. The system also provides error detection and correction for the data requested by the users. Furthermore, additional data can be added to the information storage devices during each service period and select information storage devices can be recalibrated without affecting system operation.

Abstract: An apparatus and a method for combining the characteristics of both single instruction, multiple data stream (SIMD) and multiple instruction, multiple data stream (MIMD) computer architectures into a single parallel processing computer for performing multiple instruction stream processing. Such a parallel processing computer simultaneously performs both MIMD and SIMD operations on various processors within the computer. Additionally, at specified points during program execution, certain processors, i.e., a subset of all the processors, are synchronized. Once synchronized, the processors can exchange data. Moreover, the processors that do not take part in the synchronization continue executing instructions without interruption. The apparatus and method disclosed find applicability in video servers, medical imaging, special effects and animation and location based entertainment systems among other applications.

Abstract: A processor within a parallel processing computer having a plurality of processors, where each processor is directly connected to a local storage memory. Each processor contains a principal processing element (PPE), a memory controller, and a multiplexor. The PPE executes a series of program instructions including local storage memory access instructions that cause the PPE to produce a local storage memory access request for accessing information within the local storage memory. The memory controller is connected to the PPE and a plurality of information resources of the parallel processing computer.

Abstract: The processor section comprises a matrix-line layout of processor units; each processor unit combined with adjacent processor units in row and column direction by means of IPC buses, which are two-way buses. The control/memory section comprises arrays of control/memory units corresponding one-to-one to the processor units; each control/memory unit entering instructions and data simultaneously to the corresponding units in the processor section via optical channels to carry out arithmetic operations. By providing grid-like buses on the control/memory-unit arrays, and transferring instructions and data on the buses and sending them to the processor unit corresponding one-to-one to the control/memory unit to which data are transferred via optical channels, the transfer of instructions and data is carried out efficiently between processor units beyond the third closest ones.

Abstract: A parallel computing system comprising N blocks of processors, where N is an integer greater than 1. Each block of the N blocks of processors contains M processors, where M is an integer greater than 1. Each processor includes an arithmetic logic unit (ALU), a local memory and an input/output (I/O) interface. The computing system also contains a control means, connected to each of the M processors, for providing identical instructions to each of the M processors, and a host means, coupled to each of the control means within the N blocks of processors. The host means selectively organizes the control means of each of the N blocks of M processors into at least two groups of P blocks of M processors, P being an integer less than or equal to N. In operation, the host means causes the control means within each group of P blocks of M processors to provide each group of P blocks of M processors respectively different identical processor instructions.