An open-channel storage device being configured to be controlled by a host including a bad block manager, the open-channel storage device including a buffer memory and a nonvolatile memory device. An operation method of the open-channel storage device includes performing a normal operation under control of the host, detecting a sudden power-off immediately after a program failure associated with a first data block among a plurality of memory blocks included in the nonvolatile memory device while the normal operation is performed, dumping a plurality of user data stored in the buffer memory to a dump block among the plurality of memory blocks in response to the detected sudden power-off, detecting a power-on, and performing a data recovery operation on the plurality of user data stored in the dump block in response to the detected power-on.

In one embodiment, the method includes receiving, at a storage device, a request. The request includes a request message authentication code and write protect information. The write protect information includes at least one of start address information and length information. The start address information indicates a logical block address at which a memory area in a non-volatile memory of the storage device starts, and the length information indicates a length of the memory area. The method also includes generating, at the storage device, a message authentication code based on (1) at least one of the start address information and the length information, and (2) a key stored at the storage device; authenticating, at the storage device, the request based on the generated message authentication code and the request message authentication code; and processing, at the storage device, the request based on a result of the authenticating.

A storage device and a data accessing method are disclosed, wherein the storage device includes a memory circuit and a control circuit. The memory circuit includes a plurality of multi-level cells, and each of the multi-level cells is configured to store at least a first bit, a second bit and a third bit in at least a first page, a second page and a third page. The control circuit is configured to read the first bits according to a one-time reading operation related to the first bits, read the second bits according to M-times reading operations related to the second bits, and read the third bits according to N-times reading operations related to the third bits, wherein the difference between M and N is less than or equal to one.

Embodiments provide a scheme for parametric PV-level modeling and an optimal read threshold voltage estimation in a memory system. A controller performs read operations on cells using read threshold voltages; generates CMF samples based on the read operations; and receives first and second CDF values, which correspond to CMF samples, each CDF value representing a skew normal distribution. The controller estimates first and second probability distribution parameter sets corresponding to the first and second CDF values, respectively; determines first and second PDF values using the first and second probability distribution parameter sets, respectively; and estimates, as an optimal read threshold voltage, a read threshold voltage corresponding to a cross-point of the first and second PDF values.

A plurality of storage nodes within a single chassis is provided. The plurality of storage nodes is configured to communicate together as a storage cluster. The plurality of storage nodes has a non-volatile solid-state storage for user data storage. The plurality of storage nodes is configured to distribute the user data and metadata associated with the user data throughout the plurality of storage nodes, with erasure coding of the user data. The plurality of storage nodes is configured to recover from failure of two of the plurality of storage nodes by applying the erasure coding to the user data from a remainder of the plurality of storage nodes. The plurality of storage nodes is configured to detect an error and engage in an error recovery via one of a processor of one of the plurality of storage nodes, a processor of the non-volatile solid state storage, or the flash memory.

Systems and methods for read level tracking and optimization are described. Pages from a wordline of a flash memory device read and the raw page data read from the wordline may be buffered in a first set of buffers. The raw page data for each of the pages may be provided to a decoder for decoding and the decoded page data for each of the pages buffered in a second set of buffers. First bin identifiers may be identified for memory cells of the wordline based on the raw page data and second bin identifiers may be identified for the memory cells of the wordline based on the decoded page data. Cell-level statistics may be accumulated based on the first bin identifiers and the second bin identifiers, and a gradient may be determined for respective read levels based on decoding results for each of the pages and the cell-level statistics. Settings for the read levels may be configured in the flash memory device based on the determined gradients.

Apparatus and methods are provided for operating a non-volatile memory module. In an example, a method can include filling a first plurality of pages of a first non-volatile memory with first data from a first data lane that includes a first volatile memory device, and filling a second plurality of pages of the first non-volatile memory device with second data from a second data lane that includes a second volatile memory device. In certain examples, the first plurality of pages does not include data from the second data lane.

In one embodiment, an apparatus comprises a storage device comprising a NAND flash memory. The storage device is to receive a write request from a computing host, the write request to specify data to be written to the NAND flash memory; perform a number of program loops to program the data into a plurality of cells of the NAND flash memory, wherein a program loop comprises application of a program voltage to a wordline of the memory to change the threshold voltage of at least one cell of the plurality of cells; and wherein the number of program loops is to be determined prior to receipt of the write request and based on a distribution of threshold voltages of the cells or determined based on tracking a number of program errors for only a portion of the plurality of cells.

Memory devices, systems including memory devices, and methods of operating memory devices are described, in which a memory device may select an option for a host device to access a memory array including a first portion configured to store user data and a second portion configured to store different data based on whether an ECC function of the memory device is enabled or disabled—e.g., storing ECC data when the ECC function is enabled, storing additional user data, metadata, or both when the ECC function is disabled. The host device may disable the ECC function and transmit an input to the memory device as to how to access the memory array. The memory device, based on the input, may select the option for the host device to access the memory array and communicate with the host device in accordance with the selected option.

In described examples, a memory system is accessed by reading a data line and error detection bits for the data line from a first memory. The data line and the error detection bits from the first memory are decoded to determine if an error is present in the data line from the first memory. A copy of the data line and the error detection bits are stored in a second memory. The copy of the data line and error detection bits are read from the second memory. The copy of the data line and error detection bits are decoded to determine if an error is present in the copy of the data line from the second memory.