4105 results about "Magnetic disks" patented technology

The present invention is a method for integrating a file system with a RAID array that exports precise information about the arrangement of data blocks in the RAID subsystem. The file system examines this information and uses it to optimize the location of blocks as they are written to the RAID system. Thus, the system uses explicit knowledge of the underlying RAID disk layout to schedule disk allocation. The present invention uses separate current-write location (CWL) pointers for each disk in the disk array where the pointers simply advance through the disks as writes occur. The algorithm used has two primary goals. The first goal is to keep the CWL pointers as close together as possible, thereby improving RAID efficiency by writing to multiple blocks in the stripe simultaneously. The second goal is to allocate adjacent blocks in a file on the same disk, thereby improving read back performance. The present invention satisfies the first goal by always writing on the disk with the lowest CWL pointer. For the second goal, a new disk is chosen only when the algorithm starts allocating space for a new file, or when it has allocated N blocks on the same disk for a single file. A sufficient number of blocks is defined as all the buffers in a chunk of N sequential buffers in a file. The result is that CWL pointers are never more than N blocks apart on different disks, and large files have N consecutive blocks on the same disk.

Truncation reduces the available striped data capacity of all flash channels to the capacity of the smallest flash channel. A solid-state disk (SSD) has a smart storage switch salvages flash storage removed from the striped data capacity by truncation. Extra storage beyond the striped data capacity is accessed as scattered data that is not striped. The size of the striped data capacity is reduced over time as more bad blocks appear. A first-level striping map stores striped and scattered capacities of all flash channels and maps scattered and striped data. Each flash channel has a Non-Volatile Memory Device (NVMD) with a lower-level controller that converts logical block addresses (LBA) to physical block addresses (PBA) that access flash memory in the NVMD. Wear-leveling and bad block remapping are preformed by each NVMD. Source and shadow flash blocks are recycled by the NVMD. Two levels of smart storage switches enable three-level controllers.

The present invention is directed to a device that can be placed between two adjacent vertebrae, and that is used to repair an injury or defect in the anulus of the intervertebral disk. The implant is characterized by having a flexible structure anchored to the vertebral bone, the flexible structure connected with a patch held in place over the injury or defect. The flexible structure has a hollow interior space which can sustain inside it a hydrogel cushion. The hydrogel cushion acts as a shock absorber for the spine, maintains height of the intervertebral disk space, and prevents further disk herniation due to the narrowing of the intervertebral disk space.

A method is disclosed for integrating a file system with a RAID array that exports precise information about the arrangement of data blocks in the RAID subsystem. The file system examines this information and uses it to optimize the location of blocks as they are written to the RAID system. Thus, the system uses explicit knowledge of the underlying RAID disk layout to schedule disk allocation. The method uses separate current-write location (CWL) pointers for each disk in the disk array where the pointers simply advance through the disks as writes occur. The algorithm used has two primary goals. The first goal is to keep the CWL pointers as close together as possible, thereby improving RAID efficiency by writing to multiple blocks in the stripe simultaneously. The second goal is to allocate adjacent blocks in a file on the same disk, thereby improving read back performance. The method satisfies the first goal by always writing on the disk with the lowest CWL pointer. For the second goal, a new disks chosen only when the algorithm starts allocating space for a new file, or when it has allocated N blocks on the same disk for a single file. A sufficient number of blocks is defined as all the buffers in a chunk of N sequential buffers in a file. The result is that CWL pointers are never more than N blocks apart on different disks, and large files have N consecutive blocks on the same disk.

A redundant array of independent disk (RAID) memory storage system comprising data storage blocks arranged in a first plurality of data rows and a second plurality of data columns, wherein parity data is stored in additionally defined parity blocks, and wherein numbers of data blocks in respective columns are different, to accommodate the additional diagonal parity data block that the geometry of the system requires. The system is suitable for an SSD array in which sequential disk readout is not required.

A portion of a storage controller's cache memory is used as a virtual solid state disk storage device to improve overall storage subsystem performance. In a first embodiment, the virtual solid state disk storage device is a single virtual disk drive for storing controller based information. In the first embodiment, the virtual solid state disk is reserved for use by the controller. In a second embodiment, a hybrid virtual LUN is configured as one or more virtual solid state disks in conjunction with one or more physical disks and managed using RAID levels 1-6. Since the hybrid virtual LUN is in the cache memory of the controller, data access times are reduced and throughput is increased by reduction of the RAID write penalty. The hybrid virtual LUN provides write performance that is typical of RAID 0. In a third embodiment, a high-speed virtual LUN is configured as a plurality of virtual solid state disks and managed as an entire virtual RAID LUN. Standard battery backup and redundant controller features of RAID controller technology ensure virtual solid state disk storage device non-volatility and redundancy in the event of controller failures.

A network-enabled audio device that provides a display device that allows the user to select playlists of music much like a jukebox is disclosed. The user can compose playlists from disk files, CD's, Internet streaming audio broadcasts, online music sites, and other audio sources. The user can also select a desired Web broadcast from a list of available Web broadcasts. In addition, the user can play standard audio CD's and MP3 encoded CD's and have access to local AM/FM stations. Further, the software, the user controls, and the display in the network-enabled audio device are operably configured and connected such that the user can listen to playlists that include CD's and other audio sources just as the user would choose a playlist in a jukebox. The user accesses a server site via a PC and the Internet. From the server site, the user obtains a list of the devices in his or her Internet Personal Audio Network (IPAN) and what songs are on those devices. The IPAN includes an IPAN server, an IPAN client, and IPAN software stored on the network-enabled audio device. Thus, the network-enabled audio device provides people who are or are not comfortable with computers a way of taking music from various sources and putting it into one place for listening pleasure. In one embodiment, the Personal Computer (PC) is used to compose the playlists, but the user is able to listen to playlists and other audio sources without using the PC.

A disk drive is disclosed comprising a disk for storing initial host requested (IHR) data requested by a host computer during a start-up process of the host computer, a head actuated radially over the disk, and a non-volatile semiconductor memory (NVSM) for caching at least part of the IHR data. The disk drive transmits the cached IHR data from the NVSM to the host computer during the start-up process thereby avoiding the delay associated with initializing the mechanics of the disk drive as well as conserving battery power for mobile applications.

An artificial spinal disk comprises a central capsule that is configured to slide laterally within the disk space with one or more of flexion, extension, and lateral bending of the spine so as to shift an instantaneous center of rotation of the artificial disk. In one embodiment, the invention comprises an artificial spinal disk comprising a first plate having an inwardly directed surface, a second plate having an inwardly directed surface facing generally toward the inwardly directed surface of the first plate, and a central capsule with outwardly directed opposed faces that slidably mate with the inwardly directed surfaces of the first and second plates.

An existing video game system is modified to include additional communication and storage capability via a modem and hard disk drive. In accordance with one embodiment of the present invention, the primary system security features are incorporated into a video game system expansion device having a hard disk drive. The security system does not rely on the relatively insecure video game system. The present exemplary embodiment focuses security control in a disk drive/mass media controlling engine which is physically disposed within the expansion device housing as close as possible to the hard disk drive and the downloaded video games and other data it is designed to protect. Security features are incorporated into, for example, a disk drive controlling processing engine to provide security features which extend far beyond simplistic password systems which have heretofore been utilized in conjunction with disk drive controllers. In accordance with an exemplary embodiment of the present invention, the disk controller also incorporates an encrypting engine which encrypts in accordance with a highly secure encrypting algorithm. A further level of security is provided in the illustrative embodiments by partitioning the hard drive into various partitions whose security/accessibility is tightly controlled. Each application program, e.g., a video game, has a predetermined number of private partitions, including a read only encrypted partition.

A hybrid drive controller maintains a deferred trim list that holds a subset of logical addresses of writes performed on magnetic disks. For example, if a write command is issued to an LBA space that overlaps a portion stored in flash memory and the write is to be performed on the magnetic disks, the trimming of the overlapping portion in the flash memory will be deferred. Instead of trimming, the logical addresses associated with the overlapping portion will be added to the deferred trim list and trimming of the logical addresses in the deferred trim list will be carried out at a later time, asynchronous to the write that caused them to be added to the list.

A magnetic disk including a substrate, a recording track section which is made of a magnetic member for recording and reproducing information magnetically and is provided on the substrate, and a guard band member which is provided between the recording track sections adjacent to each other so that they are substantially continued in a track direction and is harder than the magnetic member and is made of a non-magnetic material. Moreover, the magnetic member is not provided or magnetic members with a different thickness from the magnetic member forming the recording track section is provided on a lower area of the guard band member.

Systems and methods for tracking changes and performing backups to a storage device are provided. For virtual disks of a virtual machine, changes are tracked from outside the virtual machine in the kernel of a virtualization layer. The changes can be tracked in a lightweight fashion with a bitmap, with a finer granularity stored and tracked at intermittent intervals in persistent storage. Multiple backup applications can be allowed to accurately and efficiently backup a storage device. Each backup application can determine which block of the storage device has been updated since the last backup of a respective application. This change log is efficiently stored as a counter value for each block, where the counter is incremented when a backup is performed. The change log can be maintained with little impact on I/O by using a coarse bitmap to update the finer grained change log.

A near field transducer (NFT) for use in an energy assisted magnetic recording (EAMR) head and configured to direct energy to a recording media is disclosed. The NFT comprises a disk section; and a pin section extending towards an air bearing surface (ABS) from the disk section. The pin section has a proximal end adjoining the disk section and a distal end opposite to the proximal end and facing the ABS, wherein at least the distal end of the pin section has a non- rectangular cross section in a plane parallel to the ABS.

The invention provides a storage system, and a method for operating a storage system, that provides for relatively rapid and reliable takeover among a plurality of independent file servers. Each file server maintains a reliable communication path to the others. Each file server maintains its own state in reliable memory. Each file server regularly confirms the state of the other file servers. Each file server labels messages on the redundant communication paths, so as to allow other file servers to combine the redundant communication paths into a single ordered stream of messages. Each file server maintains its own state in its persistent memory and compares that state with the ordered stream of messages, so as to determine whether other file servers have progressed beyond the file server's own last known state. Each file server uses the shared resources (such as magnetic disks) themselves as part of the redundant communication paths, so as to prevent mutual attempts at takeover of resources when each file server believes the other to have failed. Each file server provides a status report to the others when recovering from an error, so as to prevent the possibility of multiple file servers each repeatedly failing and attempting to seize the resources of the others.

A disk drive includes a disk having a recording surface, a head stack assembly that includes a body portion, an actuator arm cantilevered from the body portion and a head gimbal assembly supported at the actuator arm. The head gimbal assembly includes a suspension having a first end and a second end, the first end being attached to the actuator arm, a slider coupled to the second end of the suspension, the slider comprising a transducer for reading from and writing to the recording surface. A gimbal is coupled to the second end of the suspension and to the slider. An array of diodes is attached to the suspension to protect the transducer from electrostatic discharge or electrical overstress events.

A system and method for dynamic data recovery is described. The system and method for dynamic data recovery operates on a computer storage system that includes a plurality of disk drives for storing parity groups. Each parity group includes storage blocks. Each of the storage blocks is stored on a separate disk drive such that no two storage blocks from a given parity set reside on the same disk drive. The computer storage system further includes a recovery module to dynamically recover data that is lost when at least a portion of one disk drive in the plurality of disk drives becomes unavailable. The recovery module is configured to produce a reconstructed block by using information in the remaining storage blocks of a parity set that corresponds to an unavailable storage block. The recovery module is further configured to split the parity group corresponding to an unavailable storage block into two parity groups if the parity group corresponding to the unavailable storage block spanned all of the drives in the plurality of disk drives.

An air bearing surface for read/write head of a magnetic disk drive is disclosed. The air bearing surface includes a trailing edge pad and a leading edge pad with trailing portions. A cavity is defined between the trailing edge pad and the trailing portions of the leading edge pad. A cavity patch is disposed within the cavity. The cavity patch can be disposed within the cavity towards one side of the read/write head.

An enhanced inductive coil design for use in data storage magnetic disk drives with areal density over 35 Gb/in², features a double wound twin coil that is able to achieve a yoke length of 15 μm or less by reducing the insulation spacing between the two coils. The coil further presents improved reliability by reducing the possibility of occurrence of electrical shorting. The coil is made by forming two interleafing conductors on the same layer with a demesne process. A tri-level process is implemented in the layout of the first conductor to ensure that the coil width and spacing are uniform and even, in order for the second conductor to be wound therebetween. A conformal dielectric layer of approximately 0.1 to 0.2 μm in thickness is deposited between the two conductors and serves as insulation. The two conductors are formed by a copper seed layer plating process that eliminates potential damage to the conductors during production.

A disk drive is disclosed that is responsive to standard disk-drive commands associated with disk-drive operations and to nonstandard disk-drive commands required for disk drive manufacture and quality testing. The disk drive includes a disk, a head actuated radially over the disk, and a disk control system. The disk control system responds to disk-drive commands and accesses data storage locations on the disk through the head. A serial ATA interface couples the disk control system to a host computer. The serial ATA interface is configured to transfer standard disk-drive commands from the host computer to the disk control system and is configured to not transfer nonstandard disk-drive commands from the host computer to the disk control system. The extracting means extracts a nonstandard disk-drive command that is embedded within a data block accessed using a standard disk-drive command and provides the extracted nonstandard disk-drive command to the disk control system.

A disk drive is disclosed comprising a voice coil motor (VCM) for rotating an actuator arm about a pivot in order to actuate a head over a disk. The disk is rotated by a spindle motor, and a feed-forward compensation value is computed that compensate for a non-centric alignment of the disk with respect to the spindle motor. During a calibration mode, the VCM is controlled to press the actuator arm against a crash stop, and the feed-forward compensation value is computed in response to a position error signal (PES). The PES is generated in response to embedded servo sectors recorded on the disk, wherein each embedded servo sector comprises a track address for coarse alignment and servo bursts for fine alignment.

A method and apparatus for emulating a magnetic tape storage device with a conventional, unmodified magnetic disk storage device. I/O output requests for the emulated magnetic tape storage device are intercepted to determine whether they involve a virtual tape resource that comprises a magnetic disk storage device. Tape requests to such a resource are converted into one or more conventional magnetic disk storage requests to effect an analogous operation.

A file system that balances the loading of filers and the capacity of drives that are associated with the filers is described. The file system includes a first disk drive that includes a first unused capacity and a second disk drive that includes a second unused capacity, wherein the second unused capacity is smaller than the first unused capacity. The file system further includes a first filer that is configured to fill requests from clients through access to at least the first disk drive. The file system further includes a second filer that is configured to fill requests from clients through access to at least the second disk drive. The second filer is configured to select an infrequently accessed file from the second disk drive and to push the infrequently accessed files to the first disk drive, thereby improving a balance of unused capacity between the first and second disk drives without substantially affecting a loading for each of the first and second filers.

A Pre-boot Execution Environment (PXE) boot extension is loaded upon system boot and is operable to store an iSCSI boot disk identifier identifying a remote disk drive to a shared memory location. As an operating system is loaded via iSCSI over a network connection to a remote disk, an operating system iSCSI driver is loaded. The operating system iSCSI driver reads the boot disk identifier stored in the shared memory location and uses the boot disk identifier to configure the operating system.

A method dramatically reduces the amount of data to be stored and transferred in a networked storage system. Preferably, the network storage system provides continued data protection through mirroring/replication, disk-to-disk backup, data archiving for future retrieval, and Information Lifecycle management (ILM). The idea is to leverage the parity computation that exists in RAID systems. By caching, transferring, and storing data parity or delta bytes of changes on a block as opposed to data block itself, substantial data reduction is possible without using sophisticated compression algorithms at the production side to minimize performance impacts upon production servers. Data can be computed using the parity/delta and previously existing data at mirror side, replication side, backup storage, or at retrieval time upon events such as failures or ILM operations.

The present invention may be embodied in a method of determining a repeatable runout (RRO) compensation value set for a data track on a magnetic disk in a disk drive. The track comprises a plurality of embedded sectors that define a circumferential path having RRO requiring compensation during data read and write operation. In the method, track following is performed along the track and a position error signal (PES) is determined for each servo sector. An RRO compensation value is iteratively learned for each servo sector using the previously learned value for the servo sector and using the PES for the servo sector and for adjacent servo sectors.

A system and method for enabling parallel replay of a backup memory log of client transaction request entries to a network storage appliance file system is provided. The backup memory is typically implemented as a non-volatile random access memory (NVRAM). An initiator establishes a swarm of messages with a plurality of transaction blocks pointing to logged request entries and related states associated therewith. The states represent the various phases of file system recovery and disk storage including a retrieval of disk information (data and meta-data), typically in the form of a LOAD, and a subsequent modify phase. The swarm is transferred to the file system for parallel disk information-retrieval in an interleaved process. Any transactions that cannot be performed due to a required prerequisite action (e.g. a prior file-create) are returned to the initiator for reloading once the prerequisite action has occurred.

A system of Flash EEprom memory chips with controlling circuits serves as non-volatile memory such as that provided by magnetic disk drives. Improvements include selective multiple sector erase, in which any combinations of Flash sectors may be erased together. Selective sectors among the selected combination may also be de-selected during the erase operation. Another improvement is the ability to remap and replace defective cells with substitute cells. The remapping is performed automatically as soon as a defective cell is detected. When the number of defects in a Flash sector becomes large, the whole sector is remapped. Yet another improvement is the use of a write cache to reduce the number of writes to the Flash EEprom memory, thereby minimizing the stress to the device from undergoing too many write/erase cycling.

A magnetoresistive element comprises an exchange coupling film having a under layer, an antiferromagnetic film and a ferromagnetic film, which are laminated in that order, the under layer including a metal having a face centered cubic crystal structure or hexagonal closest packing crystal structure which have a longer nearest neighbor atomic distance than that of the antiferromagnetic film. With this construction, it is possible to improve the exchange coupling field and to satisfy a stable output over a long period of time. A magnetoresistive element having a dual spin valve structure has a magnetization adjusting layer, which is antiferromagnetically connected to a pinned layer via an anti-parallel connection layer, to adjust the value of the product of the saturation magnetization of each of the magnetization adjusting layer and the pinned layer by the thickness thereof. Moreover, a magnetoresistance head use a giant magnetoresistance effect, and has at least one pair of pinned layer and free layer arranged via a non-magnetic spacer layer. The pinned layer has a pair of ferromagnetic layers which have different compositions and different coercive forces and which are antiferromagnetically connected to each other via a connection layer, so that the effective exchange coupling field of the pinned layer is 200 Oe or more.

A method is disclosed for installing a mailbox file associated with a disk storage medium of a disk drive. In accordance with exemplary embodiments of the present invention, a computer system includes a host computer, a disk drive host interface and a disk drive having a disk storage medium with a first range of disk drive host interface addressable locations. A disk drive access key is obtained from an access key server, the access key being generated by the access key server as a function of an identifying characteristic of the disk drive. A mailbox file is created in the first range of addressable locations using the access key obtained from the access key server. The disk drive is notified of a location of the mailbox file in the first range of addressable locations such that the disk drive can perform a function characterized by contents of the mailbox file.