Sandisk Technologies Inc.

Smart Storage Systems, Inc.

Western Digital Technologies, Inc.

Sandisk Enterprise IP LLC

James M Higgins

Robert W Ellis

Mark Joseph Dancho

James Fitzpatrick

Ryan R Jones

Steven Theodore Sprouse

Bernardo Rub

Jingfeng Yuan

Jeff Whaley

Aaron Keith Olbrich

Navneeth Kankani

Reed P Tidwell

Neil Richard Darragh

Jacob Schmier

Satish Babu Vasudeva

James M Kresse

Jonathan Q Tu

Yongke Sun

Alexander Kwok-Tung Mak

Vidyabhushan Mohan

David George Dreyer

Lisha Wang

Rodney Brittner

Lanlan Gu

Sheunghee Park

Mervyn Wongso

Mark David Myran

Li Li

Scott Creasman

Theron Wayne Virgin

John G Hodgdon

Neil R Darragh

Aspects of the disclosure are directed to a storage device including a memory and a controller. In some examples, the controller is configured to measure an error rate of one or more blocks of the memory. In some examples, the controller is further configured to estimate, based at least in part on the error rate, a time shift indicative of a duration of time for which the storage device was powered off. In some examples, the controller is further configured to set a read level for multiple blocks of the memory, wherein the read level is determined based at least in part on the time shift.

Data retention management after power off

The subject technology performs the following in a storage system including memory dies, where each memory die includes its own temperature sensor. The subject technology determines a temperature of each of the memory dies based on a temperature reading from each memory die's temperature sensor. The subject technology determines whether data is hot data or cold data, where hot data is more likely to be changed after it is written than cold data. In response to determining that the data is hot data, the subject technology stores the data in a memory die with a relatively higher temperature than another one of the memory dies. Further, in response to determining that the data is cold data, the subject technology stores the data in a memory die with a relatively cooler temperature than another one of the memory dies.

Data storage system and method based on data temperature

In a memory system having a storage controller and a plurality of distinct sets of non-volatile memory devices, each respective channel controller of a plurality of channel controllers, each channel controller corresponding to a distinct set of the plurality of distinct sets of non-volatile memory devices, determines a backlog of the respective channel controller in accordance with pending commands in one or more command queues, receives power credits allocated by the storage controller, based at least in part on the backlog of the respective channel controller, and while executing commands in the one or more command queues, limits execution of said commands in accordance with the received power credits. For example, limiting execution includes deferring execution of a respective command in accordance with a determination that executing the respective command would require power credits in excess of power credits available in the respective channel controller.

Distributed power management for non-volatile memory controllers

Storage system and method for die-based data retention recycling

A storage control system, and a method of operation thereof, including: a recycle write queue for providing a recycle write; a host write queue for providing a host write; and a scheduler, coupled to the recycle write queue and the host write queue, for scheduling the recycle write and the host write for writing to a memory device.

Storage control system with data management mechanism and method of operation thereof

In a memory system having a storage controller and a plurality of distinct sets of non-volatile memory devices, each respective channel controller of a plurality of channel controllers, each channel controller corresponding to a distinct set of the plurality of distinct sets of non-volatile memory devices, receives power credits allocated by the storage controller, including an average power credit and a peak power credit; and while executing commands in the one or more command queues, limits execution of said commands in accordance with the received average power credit and the received peak power credit. In some embodiments, a total number of average power credits allocated by the storage controller is variable and a total number of peak power credits allocated by the storage controller is fixed.

Distributed power management for non-volatile memory controllers using average and peak power credits allocated to memory channels

The various implementations described herein include systems, methods, and/or devices used to selectively throttle host reads in memory devices. The method includes: (1) identifying a storage location in the non-volatile memory system with high read disturbs vulnerable to reliability issues, (2) determining if the identified storage location is being throttled for host reads, (3) in accordance with a determination that the identified storage location does not satisfy the predefined read throttling criteria, initiate execution of a read operation, otherwise, enqueue read commands for deferred execution.

Selectively throttling host reads for read disturbs in non-volatile memory system

The present disclosure generally relates to solid state storage device and techniques for conserving storage capacity associated therewith. Several embodiments are presented, including a data storage device, data storage controller, and methods for using the same are provided in the subject disclosure. A data storage device includes: a plurality of memory devices, a controller coupled to the plurality of memory devices and configured to program data to and read data from the plurality of memory devices, a memory including a logical-to-physical address translation map configured to enable the controller to determine a physical location of stored data in the plurality of memory devices, where the logical-to-physical address translation map contains at least one entry that merges at least two addresses that map, respectively, to at least two physical locations in the plurality of memory devices, where the controller is configured to encode each merged entry with an error-correcting code.

Scaling large drives using enhanced DRAM ECC

The various implementations described herein include systems, methods and/or devices used for garbage collection in memory system. The method includes: (1) determining occurrences of triggering events including data reclamation events, urgent data integrity recycling events, and scheduled data integrity recycling events, and (2) recycling, in response to each of a plurality of triggering events, data in a predefined quantity of memory units from a source memory portion to a target memory portion of the memory system. A respective data reclamation event corresponds to the occurrence of host data write operations in accordance with a target reclamation to host write ratio. A respective urgent data integrity recycling event occurs when a memory portion satisfies predefined urgent read disturb criteria. A respective scheduled data integrity recycling event occurs at a rate corresponding to a projected quantity of memory units to be recycled by the memory system over a period of time.

Method and system for blending data reclamation and data integrity garbage collection

A storage system and method for die-based data retention recycling are provided. In one embodiment, a storage system comprises a controller and a plurality of memory dies. Each of the plurality of memory dies comprises its own temperature sensor, wherein at least one of the memory dies is characterized by a relatively lower endurance than at least one other of the memory dies, and wherein the at least one of the memory dies with the relatively lower endurance is positioned farther away from the controller than the at least one other of the memory dies.

The embodiments described herein are used to allocate memory in a storage system. The method includes, at a memory controller in the storage system, determining a current memory allocation for a set of memory devices, wherein the set of memory devices is formatted with a ratio of first storage density designated portions to second storage density designated portions in accordance with the current memory allocation. The method further includes detecting satisfaction of one or more memory reallocation trigger conditions. The method further includes, in response to detecting satisfaction of one or more memory reallocation trigger conditions, modifying the ratio of the first storage density designated portions to the second storage density designated portions in the set of memory devices to generate a second memory allocation for the set of memory devices.

Methods and systems for flash buffer sizing

A memory controller configures a plurality of word lines associated with a respective block of a 3D memory device in a first configuration, where the first configuration includes a set of configuration parameters for each word line of the plurality of word lines determined at least in part on the vertical positions of each word line relative to a substrate of the 3D memory device and, while the plurality of word lines are configured in the first configuration, writes data to and reads data from the respective block. For the respective block, the memory controller: adjusts a first parameter in the respective set of configuration parameters corresponding to a respective word line of the plurality of word lines in response to detecting a first trigger condition as to the respective word line and, after adjusting the first parameter, writes data to and reads data from the respective word line.

Method and system for dynamic word line based configuration of a three-dimensional memory device

Methods, systems and/or devices are used for limiting write command execution in a storage device comprising a set of non-volatile memory devices. In one aspect, the method includes (1) accessing in a holding queue host-specified write commands specified by a host system, each of the host-specified write commands specifying a number of pages to be written to the set of non-volatile memory devices; (2) in accordance with a determination that throttling is enabled: (3) determining a limit number of pages for a current throttle period in accordance with a throttle rate, the throttle rate being a maximum write rate for executing host-specified write commands; and (4) during the current throttle period, moving from the holding queue to a pending queue, for execution by the set of non-volatile memory devices, host-specified write commands whose total specified number of pages does not exceed the limit number of pages.

Method and system for limiting write command execution

In a non-volatile memory system, a fast bulk secure erase method for erasing data includes, in response to a secure erase command: applying charge to a portion of non-volatile memory in the non-volatile memory system, and performing an erase operation sufficient to remove charge from the portion of non-volatile memory to below an erase threshold. The applied charge is sufficient to program memory cells in the portion of non-volatile memory to above a pre-erase program threshold.

Secure erase of non-volatile memory

A method of operation of a data storage system includes: monitoring a data interface bus, the monitoring by a non-volatile memory controller; activating a zero bit counter for detecting a ratio of 1's to 0's on the data interface bus; and adjusting a threshold voltage (V), based on the ratio of the 1's to the 0's from the zero bit counter, by the non-volatile memory controller.

Growing community of inventors

Chandler, AZ, United States of America

James M Higgins