Abstract: A system and method is described that allows random write operations regions utilizing shingled magnetic recording. The method includes receiving a request to re-write a logical block address (LBA) with new data, wherein the LBA is mapped to a physical block address (PBA) on a storage medium. The method further includes determining whether the data is eligible for a write-in place update wherein the data is written to an area of the I-region that has previously been written with shingled data tracks, wherein the eligibility determination is based on a mapping list of LBAs to PBAs. The method also includes writing the new data to the area of the I-region determined to be eligible for a write-in place update, wherein writing the new data further includes writing management information to the I-region that identifies a starting LBA of the write-in place update, and a length of the write-in place update.

Abstract: A system and method is described that allows random write operations regions utilizing shingled magnetic recording. The method includes receiving a request to re-write a logical block address (LBA) with new data, wherein the LBA is mapped to a physical block address (PBA) on a storage medium. The method further includes determining whether the data is eligible for a write-in place update wherein the data is written to an area of the I-region that has previously been written with shingled data tracks, wherein the eligibility determination is based on a mapping list of LBAs to PBAs. The method also includes writing the new data to the area of the I-region determined to be eligible for a write-in place update, wherein writing the new data further includes writing management information to the I-region that identifies a starting LBA of the write-in place update, and a length of the write-in place update.

Abstract: A hard disk drive (HDD) provides for the logical removal of defective physical heads. The HDD includes one or more disks organized into a plurality of regions, each region having a plurality of physical block addresses (PBAs). A number of physical heads are used to read and write information to the disks. A controller is configured to translate logical block addresses (LBAs) received from an external system to PBAs used to access the one or more disks, wherein the controller is configured to logically remove a defective physical head from service by dynamically re-assigning LBAs to each of the plurality of regions while preventing LBAs from being assigned to regions associated with the defective physical head.

Abstract: While executing a command that accesses a sector on a disk-shaped recording medium placed in a data recording device, an address of a sector where it is difficult to read data is recorded in a memory. After that, a determination is made as to whether or not the data recording device is executing a command. If it is judged that the data recording device is not executing a command, the address of the sector is read from the memory, and then a bad sector is searched for by detecting whether or not it is difficult to read data from each of surrounding sectors adjacent to the sector, the address of which has been read.

Abstract: To avoid degradation of performance of a storage apparatus even when access biased to writing or reading of data is performed in a buffer memory that adopts a dual ring buffer system as a data structure. A sector buffer for caching an access request is provided in a DRAM of the storage apparatus. The sector buffer has a first ring buffer (BUF_W) that temporarily holds an external write request for a recording medium in advance of its process to the recording medium, and a second ring buffer (BUF_R) that retains data read from the recording medium according to an external read request for the recording medium. An MPU of the storage apparatus shifts a BPAGE of the BUF_R or BUF_W according to external access patterns to the recording medium to thereby change the buffer sizes of the BUF_R and BUF_W.

Abstract: While executing a command that accesses a sector on a disk-shaped recording medium placed in a data recording device, an address of a sector where it is difficult to read data is recorded in a memory. After that, a determination is made as to whether or not the data recording device is executing a command. If it is judged that the data recording device is not executing a command, the address of the sector is read from the memory, and then a bad sector is searched for by detecting whether or not it is difficult to read data from each of surrounding sectors adjacent to the sector, the address of which has been read.

Abstract: A disk drive apparatus and control method thereof that enable the latency that may occur in a multi-drive environment to be prevented, and performance to be improved. A microprogram is provided that includes a queue handler that stores commands issued by the host in a queue area, performs reordering and determines the command to be executed, and requests execution of the determined command; an interface handler that executes interface-side processing, including data transfer between the host and the drive apparatus by means of a command for which execution has been requested; and a drive handler that executes drive-side processing by means of a command for which execution has been requested, and requests the drive apparatus to perform read/write operations relating to command execution; interface-side processing and drive-side processing are separated with regard to command processing, and interface-side processing does not affect the start of drive-side processing.

Abstract: The present invention provides, at a lower cost, a highly reliable data reading method and data reading apparatus that can improve backward sequential reading performance. The disk drive is provided with a magnetic disk and a control section having an HDC, a RAM, an MPU controlling the operation of the entire HDD, including control of the HDC, a ROM, and an I/F for connecting to an external host device. The control section executes a backward reading detection step that detects backward reading, a step of receiving a command that reads a block of a first length from a first LBA, a step that reads a block of the first length from the first LBA when backward reading is detected, and a step that pre-fetches a second block from a second LBA smaller than the first LBA; when backward reading is detected, upon completion of the reading of data from the disk, the reading of data predicted to be requested by the next command begins immediately.

Abstract: The present invention provides, at a lower cost, a highly reliable data reading method and data reading apparatus that can improve backward sequential reading performance. The disk drive is provided with a magnetic disk and a control section having an HDC, a RAM, an MPU controlling the operation of the entire HDD, including control of the HDC, a ROM, and an I/F for connecting to an external host device. The control section executes a backward reading detection step that detects backward reading, a step of receiving a command that reads a block of a first length from a first LBA, a step that reads a block of the first length from the first LBA when backward reading is detected, and a step that pre-fetches a second block from a second LBA smaller than the first LBA; when backward reading is detected, upon completion of the reading of data from the disk, the reading of data predicted to be requested by the next command begins immediately.

Abstract: The present invention provides, at a lower cost, a highly reliable data reading method and data reading apparatus that can improve backward sequential reading performance. The disk drive is provided with a magnetic disk and a control section having an HDC, a RAM, an MPU controlling the operation of the entire HDD, including control of the HDC, a ROM, and an I/F for connecting to an external host device. The control section executes a backward reading detection step that detects backward reading, a step of receiving a command that reads a block of a first length from a first LBA, a step that reads a block of the first length from the first LBA when backward reading is detected, and a step that pre-fetches a second block from a second LBA smaller than the first LBA; when backward reading is detected, upon completion of the reading of data from the disk, the reading of data predicted to be requested by the next command begins immediately.