Abstract: A reader of a magnetic recording head includes a sensor stack, a first side shield and a second side shield disposed on opposite sides of the sensor stack in a cross-track dimension, and a bridge. The bridge is configured to align magnetic moments of the first side shield and the second side shield. The bridge is disposed above the sensor stack relative to a media-facing surface of the magnetic recording head and proximate to the first side shield and the second side shield.

Abstract: A hybrid storage device with three-level memory mapping is provided. An illustrative device comprises a primary storage device comprising a plurality of primary sub-blocks; a cache memory device comprising a plurality of cache sub-blocks implemented as a cache for the primary storage device; and a controller configured to map at least one portion of one or more primary sub-blocks of the primary storage device stored in the cache to a physical location in the cache memory device using at least one table identifying portions of the primary storage device that are cached in one or more of the cache sub-blocks of the cache memory device, wherein a size of the at least one table is independent of a capacity of the primary storage device.

Abstract: Apparatus and method for transferring data in a data storage system, such as but not limited to a hard disc drive (HDD). An optical link is provided between an analog front end (AFE) of a data storage device controller circuit (SOC) and a preamplifier/driver circuit (preamp) mounted to a rotary actuator to transfer an analog domain signal. A selected component is extracted from the signal using a modulation element such as a micro-resonance ring (MRR) or a Mach-Zehnder Interferometer Modulation (MZM) device. The extracted component is forwarded to a processing circuit to facilitate a transfer of data between a local memory and a non-volatile memory (NVM). The optical link includes a flexible portion in a flex circuit affixed to the rotary actuator and which supports the preamp. Multiplexed read, write, and power control signals are concurrently transmitted via the optical link. The link can concurrently service multiple head-disc assemblies (HDAs).

Abstract: The present disclosure includes embodiments of an electronic device having a housing that defines an interior gas space, and desiccant disposed therein. The desiccant includes one or more zeolite compositions to manage the relative humidity of the interior gas space.

Abstract: A method includes importing an object into a first data storage device, obtaining static metadata relating to the object, and obtaining dynamic metadata relating to the importation of the object. The static metadata and the dynamic metadata are hashed to create a block hash for the object and the importation of the object. The imported object and the block hash are stored in the first data storage device.

Abstract: Systems and methods are disclosed for data storage redeployment. For example, a controller of a data storage array can implement a process to determine when, or if, to redeploy a data storage device from a first data storage usage or tier having a first performance requirement to a second data storage usage or tier having a second performance requirement. In some embodiments, the first data storage tier performance requirement is for hot-data storage, and the second data storage tier performance requirement is for cold-data storage. Various criterion (e.g., a data storage device performance metric) threshold, such as a workload (e.g., LBAs written, LBAs read, or both) of the data storage device or bit error rate (BER), may be utilized in a redeployment determination.

Abstract: A data storage device can have one or more rotating data media with data tracks that are radially disposed from a central spindle. The data tracks may be logically divided into multiple regions while a write strategy is generated with a region module to set a sequence of different regions for future data writes. Receipt of a data write request to the data storage media from a host can prompt the region module to classify the data write request as a sequential or random write in order to intelligently select a region to satisfy the data write request based on the write strategy to maximize data writing consistency for data associated with the data write request.

Abstract: A data storage system can consist of a network controller connected to a data storage device and a remote host. An attack mitigation strategy may be generated with an attack module connected to the network controller in response to detected data storage conditions in the data storage device. The attack mitigation strategy can be executed with the attack module by sending separate first and second security queries to the data storage device over time. At least a powered move attack can then be identified based on the second security query.

Abstract: Cache coherency of a global address space of a cache can be maintained with one or more tier control units (TCUs). The global address space of the cache may be shared by multiple domains. Domains may include multiple controllers and a local interconnect operatively coupling the controllers to the cache. The local interconnect of each domain may maintain a cache coherency of a local address space of the cache shared by the controllers of the domain. The one or more TCUs may be operatively coupled to the local interconnects of the domains to maintain the cache coherency of the global address space.

Abstract: Features are detected from a sensor signal via a deep-learning network or other feature engineering methods in an edge processing node. Machine-learned metadata is created that describes the features, and a hash is created with the machine-learned metadata. The sensor signal is stored as a content object at the edge processing node, the object being keyed with the hash at, the edge processing node.

Abstract: A computation is divided into computation tasks that are sent to worker nodes and distributed results are received in response. A redundant subtask is sent to each of the worker nodes, the redundant subtask being a random linear combination of the computation tasks sent to others of the worker nodes. The worker nodes perform the redundant subtasks to produce redundant results. The redundant result of each worker node is combined with distributed results of others of the worker nodes to determine whether one or more of the worker nodes are acting maliciously. Optionally, the worker nodes can be initially evaluated for trustworthiness using a homomorphic hash function applied to an initial computation task and applied to results of the initial tasks. If the results of both hash functions match, then the worker nodes are considered trustworthy and can be used for subsequent computations with redundant subtasks as described above.

Abstract: Systems and processes are disclosed to preserve data integrity during a storage controller failure. In some examples, a storage controller of an active-active controller configuration can back-up data and corresponding cache elements to allow a surviving controller to construct a correct state of a failed controller's write cache. To accomplish this, the systems and processes can implement a relative time stamp for the cache elements that allow the backed-up data to be merged on a block-by-block basis.

Abstract: Systems and methods are disclosed for detecting shingled overwrite errors. When a read error is encountered when reading from shingled recording tracks, a processor may determine whether the read error is an error caused by shingled overwriting. The processor may determine whether the read error is caused by shingled overwriting by determining read signal quality of one or more sectors preceding the read error, such as based on a bit error count or bit error ratio (BER), and comparing the read signal quality to a threshold value. The processor may determine that the read error is caused by shingled overwriting when the read signal quality value is lower than the threshold.

Abstract: Systems and methods are disclosed for the intelligent scheduling of garbage collection operations on a solid state memory. In certain embodiments, a method may comprise initiating a garbage collection process for a solid state memory (SSM) having a multiple die architecture, determining an order of die access for the garbage collection process based on an activity table indicating a use of one or more die in the multiple die architecture, and performing the garbage collection process based on the determined order of die access. Garbage collection reads may be directed to idle die to avoid conflicts with die busy performing other operations, thereby improving system performance.

Abstract: Hard errors are determined for an unsuccessful decoding of codeword bits read from NAND memory cells via a read channel and input to a low-density parity check (LDPC) decoder. A bit error rate (BER) for the hard errors is estimated and BER for the read channel is estimated. Hard error regions are found using a single level cell (SLC) reading of the NAND memory cells. A log likelihood ratio (LLR) mapping of the codeword bits input to the LDPC decoder is changed based on the hard error regions, the hard error BER, and/or the read channel BER.

Abstract: Exemplary methods and apparatus may provide optical gates and optical switches using such optical gates. Each optical gate may include a semiconductor optical amplifier that is placed in a substrate. The semiconductor optical amplifier may be coupled to input and output couplers to receive and selectively output optical signals into and out of the substrate.

Abstract: A near-field transducer or heat sink is formed via a first process. The near-field transducer or heat sink is transfer-printed to a read/write head via a second process.

Abstract: A hard disk drive includes a base deck and a cover. The cover is coupled to the base deck to create an enclosure. The hard disk drive also includes tape that covers at least a portion of the cover and the base deck. The tape includes an adhesive layer, which includes an adhesive material and a moisture-absorbent material.

Abstract: A composite layout to store one or more extents of a data object in a first storage system and one or more extents of the data object in a second, different storage system. The first storage system may be configured for the efficient storage of small chunks of data such as, e.g., chunks of data small than the addressable block size of the storage devices used by the storage systems.

Abstract: A method includes providing a public encryption key and a seed to a party and receiving a first encrypted data set encrypted using the public encryption key and marked by the party with a first mark based on the seed. The method also includes aggregating the first encrypted data set into an aggregated data set at an aggregator and receiving an indication that a first operation associated with the party has been performed on the aggregated data set. In response to the receiving, updating the first encrypted data set of the aggregated data set by updating the first mark to a second mark according to the first operation, generating a verification encrypted data set according to at least the second mark and at least the corresponding first operation, verifying the aggregated data set by comparing the updated first encrypted data set and the verification encrypted data set.