Abstract: A data storage virtualization subsystem (SVS) for providing storage to a host entity is disclosed. The SVS comprises a storage virtualization controller for connecting to the host entity, at least one physical storage device (PSD) pool, and at least one PSD is designated to be a pool spare PSD to the at least one PSD pool. The at least one PSD pool comprises at least one PSD to store user data or associated redundant information and is given a pool ID for identifying the PSD pool.

Abstract: The invention discloses a method and controller for processing data multiplication in a RAID system. Map tables are generated for all values in a field, respectively. The length of an XOR operation unit is chosen to be appropriate w bits (e.g., 32 bits or 64 bits). One or several XOR operation units form a multiplication unit of a data sector. When computing on-line, data in a disk drive of a disk array are performed with XOR operations in accordance with one of the map tables using an XOR operation unit as one unit while computing on the multiplication unit to obtain a product of multiplication. Making use of the RAID system established according to the disclosed method, only XOR operations are required to compute parity data or recover damaged user data. Moreover, several calculations can be performed simultaneously. Therefore, the efficiency of the RAID system can be effectively improved.

Abstract: A storage virtualization computer system. The storage virtualization computer system comprises a host entity for issuing an IO request, a SAS storage virtualization controller coupled to the host entity for executing IO operations in response to the IO request, and at least one physical storage device, each coupled to the storage virtualization controller through a SAS interconnect, for providing data storage space to the storage virtualization computer system through the SAS storage virtualization controller.

Abstract: A redundant external storage virtualization computer system. The redundant storage virtualization computer system includes a host entity for issuing an IO request, a redundant external SAS storage virtualization controller pair coupled to the host entity for performing an IO operation in response to the IO request issued by the host entity, and a plurality of physical storage devices for providing storage to the computer system. Each of the physical storage devices is coupled to the redundant storage virtualization controller pair through a SAS interconnect. The redundant storage virtualization controller pair includes a first and a second SAS storage virtualization controller both coupled to the host entity. In the redundant SAS storage virtualization controller pair, when the second storage virtualization controller is not on line, the first storage virtualization controller will take over the functionality originally performed by the second storage virtualization controller.

Abstract: A method for committing cached data to storage media including a host entity and a physical storage device (PSD), comprising: the host entity issuing a write IO request to the PSD being in write-back caching mode to write data from a host memory to the PSD; the host entity receiving a successful IO completion response associated with the write IO request from the PSD and recording an entry of the write IO request to a selected list; the host entity issuing a synchronized cache IO request to the PSD; the PSD responding a successful IO completion response of the synchronized cache IO request to the host entity; the host entity extracting the entry of the write IO request from the selected list before issuing the synchronized cache IO request; and the host entity engaging completion processing of write IO request corresponding to the entry of the write IO request extracted.

Abstract: A method for performing adaptive write caching in a storage virtualization subsystem is disclosed. The method comprising steps of: defining criteria associated with an operation state of the storage virtualization subsystem for performing write caching; analyzing the characteristics of a stream of at least one write IO request sent out by a host entity to make a determination of whether the stream meets the criteria; receiving a new write IO request by the subsystem from the host entity; and performing write caching to write data associated with the new write IO request to the PSD array according to the determination.

Abstract: A redundant controller storage virtualization subsystem performing host-side IO rerouting and dynamic logical media unit reassignment. In one embodiment, when a host IO request is received by a storage virtualization controller that is not a logical media unit owner of the logical media unit addressed by the IO request, the IO can be rerouted to the alternate storage virtualization controller, the logical media unit owner, to be executed. In another embodiment, the assignment of logical media unit owner can be dynamically reassigned to the receiving storage virtualization controller which was originally not the logical media unit owner such that the receiving storage virtualization controller becomes new logical media unit owner to execute the IO request. In a further embodiment, the dynamic logical media unit reassignment can be performed according to the operating condition(s) of the storage virtualization system so as to improve the performance of the storage virtualization system.

Abstract: A redundant controller storage virtualization subsystem performing host-side IO rerouting and dynamic logical media unit reassignment. In one embodiment, the assignment of logical media unit owner can be dynamically reassigned to the receiving storage virtualization controller which was originally not the logical media unit owner such that the receiving storage virtualization controller becomes new logical media unit owner to execute the IO request. In another embodiment, the dynamic logical media unit reassignment can be performed according to the operating condition(s) of the storage virtualization system so as to improve the performance of the storage virtualization system. In a further embodiment, the controller storage virtualization subsystem can perform host-side IO rerouting when the timing for performing dynamic logical media unit reassignment is not reached.

Abstract: A storage system and the cache device of the file system thereof are provided by the present invention. Each file system comprises at least one disk cache composed of a data cache unit used to temporarily store regular data and a plurality of dedicated cache units used to temporarily store special data, in order to avoid the loss of the special data owing to accessing the regular data when the storage system frequently accesses the data in the file system or accesses larger files thereof. The cache units mentioned above support a write-back caching function. When the host accesses the file data in a disk drive, the modified regular data and the metadata are stored in the corresponding cache units, and then the modified data is written into the disk drive by means of the cache units.

Abstract: A storage virtualization computer system. The storage virtualization computer system comprises a host entity for issuing an IO request, a storage virtualization controller coupled to the host entity for executing IO operations in response to the IO request, and a at least one physical storage device, each coupled to the storage virtualization controller through a point-to-point serial-signal interconnect, for providing storage to the storage virtualization computer system through the storage virtualization controller. As an example, the point-to-point serial-signal interconnect can be a Serial ATA IO device interconnect.

Abstract: A JBOD subsystem for providing storage to a host entity. The JBOD subsystem contains at least one external JBOD emulation controller coupled to the host entity for emulating IO operations in response to the IO requests and a set of at least one physical storage device coupled to the JBOD emulation controller for providing storage to the host entity through the JBOD emulation controller. The JBOD emulation controller defines at least one logical media unit (LMU) consisting of sections of the set of physical storage device (PSD) and communicates with the PSD through a point-to-point serial-signal interconnect. As an example, the point-to-point serial-signal interconnect can be a Serial ATA IO device interconnect.