Abstract: A storage system generates a low-density parity check (LDPC) code from a plurality of subcodes. The storage system stores each subcode in a different page of a word line in the memory. The subcode can be stored in one plane in the memory or across multiple planes. When the subcodes are stored across multiple planes, they can be stored in a checkboard pattern.

Abstract: Apparatus, media, methods, and systems for data storage systems and methods for optimized scheduling of background management operations. A data storage system may comprise a controller. The controller is configured to determine a timeout value of an adaptive timeout parameter of the data storage system. The controller is configured to determine whether a first host operation is received. The controller is configured to, when the first host operation is not received, determine whether the timeout value satisfies a threshold value. The controller is configured to, when the timeout value satisfies the threshold value, cause one or more background management operations to be executed at the data storage system.

Abstract: A storage device includes a controller that can dynamically adjust the zone active limit (ZAL) for a zoned namespace (ZNS). Rather than assuming a worst-case scenario for the ZNS, the ZAL can be dynamically adjusted, even after providing the ZAL to a host device. In so doing, device behavior changes due to factors such as temperature, failed or flipped bit count, and device cycling can be considered as impacting the ZAL. The ZAL can then be adjusted over time, and the new ZAL can be communicated to the host device. As such, rather than a fixed, worst-case ZAL, the host device will receive updated ZAL values over time as the device performs.

Abstract: Read reference levels are calibrated by calibrating integration times. An integration time is the length of time for which the charge on a sense node is allowed to change while the memory cell is being sensed. Calibrating the integration time is much faster than calibrating the reference voltage itself. This is due, in part, to reducing the number of different reference voltages that need to be applied during calibration. Calibrating the integration time may use different test integration times for a given read reference voltage, thereby reducing the number of read reference voltages. Hence, calibrating the integration time(s) is very efficient timewise. Also, power consumption may be reduced.

Abstract: The present disclosure generally relate to dynamically changing predictive latency related attributes to increase the deterministic window (DTWIN) of operation. The host device workload characteristics as well as the memory device's current condition provide valuable information for the duration of the DTWIN. If the memory device is near the end of life, then the DTWIN duration will be smaller. Additionally, if the workload from the host device is heavy, then the DTWIN duration will also be smaller. Rather than utilizing a fixed DTWIN duration based upon worst case scenarios for host device workload and memory device condition, dynamically adjusting the DTWIN duration based upon the workload and condition will provide a DTWIN duration that can gradually decrease over time from a much longer DTWIN duration than is currently available.

Abstract: A storage apparatus includes non-volatile memory cells formed on a memory die, each memory cell configured to hold bits of data, and a control circuit. The control circuit is configured to calculate parity data for data to be stored in the memory cells and program the memory cells to first distributions. The control circuit is also configured to read memory cells in the first distributions, recover the data from results of reading the memory cells in the first distributions combined with the parity data, and further program the memory cells from the first distributions to second distributions to store the data. To improve the accuracy of recovering the encoded foggy phase data, techniques are presented to calibrate the voltage levels used in sensing the foggy state distributions.

Abstract: A control circuit on a control die compensates for interference caused by adjacent memory cells on target memory cells on a memory die. The compensation may be based on the data states of the adjacent memory cells. Data latches may be used to store data states of the memory cells. However, reading the target memory cells can over-write the data states of the adjacent memory cells in the data latches. The control die may store data state information for the adjacent memory cells prior to sensing the target memory cells (e.g., prior to a decoding error of a codeword in the target cells). Saving the data state information on the control die reduces storage requirements of the memory die and alleviates the need to sense the adjacent memory cells again if decoding the codeword in the target memory cells fails.

Abstract: An adaptive-feedback-based read-look-ahead management system and method are provided. In one embodiment, a method for stream management is presented that is performed in a storage system. The method comprises performing a read look ahead operation for each of a plurality of streams; determining a success rate of the read look ahead operation of each of the plurality of streams; and allocating more of the memory for a stream that has a success rate above a threshold than for a stream that has a success rate below the threshold. Other embodiments are provided.

Abstract: A storage apparatus includes non-volatile memory cells formed on a memory die, each memory cell configured to hold bits of data, and a control circuit formed on the memory die. The control circuit is configured to calculate parity data for data to be stored in the memory cells and program the memory cells to first distributions. The control circuit is also configured to read memory cells in the first distributions, recover the data from results of reading the memory cells in the first distributions combined with the parity data, and further program the memory cells from the first distributions to second distributions to store the data. In some cases, the recovered data may have a high bit error rate. To handle higher bit error rates, the use of soft bit data is incorporated into an encoded foggy-fine scheme.

Abstract: The present disclosure generally relates to scheduling zone-append commands for a zoned namespace (ZNS). Rather than taking zone-append commands in order or randomly, the zone-append commands can be scheduled in the most efficient manner consistent with the open zones of the ZNS. A zone priority is determined based upon the length of time that a zone has been open together with the zone status. Generally, the older the zone and/or the more full that a zone is increases the priority. Once the zone priority is established, the zone-append commands are scheduled to ensure the zone-append commands for the high priority zones are processed first so that the open zone can be filled prior to closing.

Abstract: The present disclosure generally relates to data storage devices, such as solid state drives (SSDs). A read threshold calibration operation is utilized to generate a calibrated read threshold for one or more voltage states of a cell of a MLC memory. A single-level cell (SLC) read is then executed to sense the ratio of bit values at the read thresholds of the voltage states, where SLC read refers to reading at a single read threshold, rather than to the cell type. The sensing results in a binary page with certain statistics of 1's and 0's. The ratio of 1's (or 0's) in the binary page is used to determine a deviation from the expected ratio, where the deviation is used to adjust the calibrated read threshold to match the voltage states of the MLC memory.

Abstract: Technology for two-sided adjacent memory cell interference mitigation in a non-volatile storage system is disclosed. During reading of target memory cells, the storage system applies a suitable magnitude read pass voltage to a first unselected word line adjacent to a target word line to compensate for interference from adjacent cells on the first unselected word line while applying a suitable magnitude read reference voltage to the target word line to compensate for interference from adjacent cells on a second unselected word line on the other side of the target word line. The read pass voltage may compensate for interference due to charge being added to when programming cells on the first unselected word line after programming the target cells. The read reference voltage may compensate for interference due to charge movement near the target cells that results from charge stored in the cells on the second unselected word line.

Abstract: Methods and apparatus for managing and optimizing data storage devices that include non-volatile memory (NVM) are described. One such method involves deriving a hint for one or more logical block addresses (LBAs) of a storage device based on information received from a host device and/or physical characteristics of the storage device, such as LBAs that are invalidated together; grouping the LBAs into one or more clusters of LBAs based on the derived hint and a statistical analysis of the physical characteristics of the storage devices; allocating available physical block addresses (PBAs) in the storage device to one of the LBAs based on the one or more clusters of LBAs to achieve optimization of a data storage device.

Abstract: Systems and methods for compacting and anonymizing telemetry data in a storage system. A controller of a storage device may generate telemetry data based on collected features indicative of the performance of the storage device. The controller may store the telemetry data in the telemetry memory of the storage device. The controller may then transform the telemetry data into transformed telemetry data based on a dimension reduction algorithm, and transmit the transformed telemetry data to the host device.

Abstract: Recurrent Neural Networks (RNNs) wherein a non-volatile memory (NVM) array provides a memory bank for the RNN. The RNN may be a Neural Turning Machine (NTM) and the memory bank may be an NTM matrix stored in the NVM array. In some examples, an NTM controller sets the size of the NTM matrix based on a storage access granularity of the NVM array. For instance, if the NVM reads and writes data in flash memory unit (FMUs), the NTM controller sets the size of the NTM matrix to correspond to the size of an integer number of FMUs. In some examples, the NVM array includes on-chip NTM circuitry configured to perform at least some NTM read head and write head operations. Threshold-based processing is described that can reduce an amount of NTM data read from the NVM array. In other examples, volatile memory is employed rather than an NVM array.

Abstract: A control circuit on a control die compensates for interference caused by adjacent memory cells on target memory cells on a memory die. The compensation may be based on the data states of the adjacent memory cells. Data latches may be used to store data states of the memory cells. However, reading the target memory cells can over-write the data states of the adjacent memory cells in the data latches. The control die may store data state information for the adjacent memory cells prior to sensing the target memory cells (e.g., prior to a decoding error of a codeword in the target cells). Saving the data state information on the control die reduces storage requirements of the memory die and alleviates the need to sense the adjacent memory cells again if decoding the codeword in the target memory cells fails.

Abstract: A method and apparatus for calibrating read threshold for cells of a target wordline (WL) that may be conducted on a die, in a controller connected to a memory die, or both. Voltage values of one or more adjacent WL cells are read, and based on the voltage values of the adjacent cells, cells of the target WL are grouped. A read threshold calibration is carried out on each group. The calibration thresholds are then used for read operations on the cells of each distinct group of the target WL.

Abstract: A memory includes, in one embodiment, one or more storage elements; read/write circuitry; and compressed bit circuitry. The read/write circuitry is configured to read a set of hard bits from the one or more storage elements, and sense a set of soft bits while reading the set of hard bits from the one or more storage elements, the set of soft bits having a first fixed size, and the set of soft bits indicating a reliability of the set of hard bits. The compressed soft bit circuitry is configured to generate, with a fixed size soft bit lossy compression algorithm, a fixed size compressed soft bits by compressing the set of soft bits, the fixed size compressed soft bits having a second fixed size that is smaller than the first fixed size, and output the fixed size compressed soft bits to a memory-to-controller bus.

Abstract: An adaptive-feedback-based read-look-ahead management system and method are provided. In one embodiment, a method for stream management is presented that is performed in a storage system. The method comprises performing a read look ahead operation for each of a plurality of streams; determining a success rate of the read look ahead operation of each of the plurality of streams; and allocating more of the memory for a stream that has a success rate above a threshold than for a stream that has a success rate below the threshold. Other embodiments are provided.

Abstract: Embodiments of the present disclosure generally relate to storage devices, such as SSDs. A data storage device comprises an encrypted interface, one or more flash memory devices, and a controller configured to receive one or more workloads of data through the encrypted interface. Upon a threshold being met, the controller performs a diagnosis of one or more operating parameters of the one or more workloads of data. Based on the diagnosis, the data storage device is optimized by recalibrating one or more of: a partitioning of bits per cell of the one or more flash memory devices, one or more flash management parameters of the data storage device, and a programming rate of the storage device.