Abstract: An integrated I/O controller in an integrated circuit is provided for centralized data management. The integrated circuit includes a host interface, a disk interface, and a mapping controller implemented in hardware to speed data processing and provide fault tolerance as exemplified with RAID configurations. The mapping controller provides block mapping across a plurality of peripherals or disk drives in a disk array. The integrated I/O controller can be utilized in storage area network systems and network area storage systems as well as other networking systems or devices.

Abstract: A multi-ported storage area network (SAN) controller system with command completion that utilizes optimal port selection. The system determines the optimal port for command completion based on criteria such as loop bandwidth utilization or port throughput maximization, and allows data and response information to occur via the optimal port regardless of the receiving port. This is accomplished through port aliasing (spoofing) of port identities, in which the receiving port identity is substituted into a sending port identity by a distributed control entity. In this way, any port within the SAN may return data or status to the originating host.

Abstract: A storage element pending command queue prioritization system using multiple pending queues each assigned to a particular RAID command type. Pending commands from each of the queues are organized in such a way that lower priority commands are guaranteed a fixed amount of storage element bandwidth. Storage element throughput is optimized by limiting higher priority commands to a maximum service level and processing lower priority requests with the added storage element bandwidth, allowing lower priority requests to exceed their minimum service levels.

Abstract: A method of efficiently preventing data loss, specifically a RAID 5 write hole, in data storage system by storing valid parity information at the storage controller level during data write operations. The method employs the use of redundant data structures that hold metadata specific to outstanding writes and parity information. The method uses the redundant data structures to recreate the write commands and data when a system failure occurs before the writes have completed.

Abstract: A networked storage system controller architecture is capable of n-way distributed data redundancy using dynamically first-time allocated mirrored caches. Each storage controller has a cache mirror partition that may be used to mirror data in any other storage controller's dirty cache. As a storage controller receives a write request for a given volume it determines the owning storage controller for that volume. If another storage controller owns the volume requested, the receiving storage controller forwards the request to the owning storage controller. If no mirror has been previously established, the forwarding storage controller becomes the mirror. Thus, as data is received from the host, the receiving storage controller stores the data into its mirrored cache partition and copies the data to the owning storage controller.

Abstract: An I/O controller having separate command and data paths, thereby eliminating the bandwidth used by the commands and thus increasing bandwidth available to the data buses. Additionally, the I/O controller uses multiple dedicated data paths, for example, dedicated distributed buses, and provides increased speed due to improved hardware integration. The I/O controller employs distributed processing methods that decouple the external microprocessor from much of the decision-making, thereby providing improved operating efficiency and thus more useable bandwidth at any given clock frequency. Accordingly, the I/O controller is capable of maximizing I/O operations (IOPS) on all I/O ports by functioning at the rate of I/O connections to hosts and storage elements without becoming a bottleneck.

Abstract: An integrated I/O controller in an integrated circuit is provided for centralized data management. The integrated circuit includes a host interface, a disk interface, and a mapping controller implemented in hardware to speed data processing and provide fault tolerance as exemplified with RAID configurations. The mapping controller provides block mapping across a plurality of peripherals or disk drives in a disk array. The integrated I/O controller can be utilized in storage area network systems and network area storage systems as well as other networking systems or devices.

Abstract: A RAID controller with decentralized transaction processor controllers and a decentralized cache allows for unlimited scalability in a networked storage system. Virtualization is provided through a map-and-forward function in which a virtual volume is mapped to its logical volumes at the controller level. Any controller in the system can map a request from any host port to any logical storage element. The network storage system provides a controller/virtualizer architecture for providing mirror consistency in a virtual storage environment in which different hosts may read or write to the same logical block address simultaneously. Each storage controller or virtualization engine controls access to a specific set of storage elements. One virtualizer engine is the coordinator, and monitors all write requests and looks for potential data conflicts. The coordinator alleviates conflicts by holding specific requests in a queue until execution of those request causes no data inconsistencies or cache incoherencies.

Abstract: A method of predictive baseline volume profile creation for new volumes in a networked storage system and a system for dynamically reevaluating system performance and needs to create an optimized and efficient use of system resources by changing volume profiles as necessary. The system gathers statistical data and analyzes the information through algorithms to arrive at an optimal configuration for volume clusters. Clusters are then reallocated and reassigned to match the ideal system configuration for that point in time.

Abstract: A system for mapping between logical addresses and storage units of a plurality of storage volumes which comprise a storage system. For each volume, logical addresses are mapped to storage units using a volume mapping table. Each volume mapping table is comprised of a plurality of segments. Each segment need not be contiguously allocated to another segment of the same table. Thus, each volume mapping table can be independently expanded or reduced without affecting other volume mapping tables. A hash function, a hash table, a segment table, and a redundancy group descriptor table may also be used to help manage the segments of the volume mapping tables.

Abstract: A method of managing bad blocks in a RAID storage system. The system restores physical storage media and stripe redundancy by reassigning sectors and creating a bad block tracking structure. The bad block tracking structure consists of a volume map, a redundancy group table, and a bad block table that stores a bad block list. Redundancy is achieved through RAID 1 or RAID 10 mirroring rather than through the parity restoration required by conventional systems. The tracking structure returns media error status data to the originating host on volume read commands. The structure accepts volume write data from the originating host and then deletes the bad block tracking structure.