Seagate Technology Incorporated

Kyumsung Lee

Steven Scott Williams

David W Claude

Benjamin J Scott

Stacey Secatch

Stephen H Perlmutter

Robert William Dixon

Andrew J Louder

Jeff Rogers

Apparatus and method for managing metadata in a data storage device, such as a solid-state drive (SSD). In some embodiments, a non-volatile memory (NVM) includes a population of semiconductor memory dies. The dies are connected a number of parallel channels such that less than all of the semiconductor dies are connected to each channel. A controller circuit apportions the semiconductor memory dies into a plurality of die sets, with each die set configured to store user data blocks associated with a different user. A separate set of map data is generated to describe user data blocks stored to each die set. The controller circuit stores the respective sets of map data in the associated die sets so that no die set stores map data associated with a different die set. The die sets may be arranged in accordance with the NVMe (Non-Volatile Memory Express) specification.

Segregating map data among different die sets in a non-volatile memory

A data storage device can be arranged with a semiconductor memory having a plurality of erasure blocks accessed by a controller to store data. An access count for each respective erasure block can be generated to allow a wear range for the semiconductor memory to be computed based on the respective access counts with the controller. A performance impact of the wear range is evaluated with the controller in order to intelligently alter a deterministic window of a first erasure block of the plurality of erasure blocks in response to the performance impact.

Data storage device with wear range optimization

A semiconductor data storage memory can receive data access commands into a queue in a first time sequence that correspond with the transfer of data between a host and portions of the memory. The memory may be divided into separate portions that each have a different owner and the access commands may be issued to each of the respective separate portions. The access commands can subsequently be executed in a different, second time sequence responsive to estimated completion times for each of the access commands based on measured completion times for previously serviced, similar commands to maintain a nominally consistent quality of service level for each of the respective owners.

Deterministic optimization via performance tracking in a data storage system

Apparatus and method for storing data in a non-volatile memory (NVM), such as a flash memory in a solid-state drive (SSD). In some embodiments, a distributed storage space of the NVM is defined to extend across a plural number of regions of the NVM. A non-standard parity data set is provided having a plural number of data elements greater than or equal to the plural number of regions in the storage space. The data set is written by storing a first portion of the data elements and a first parity value to the plural number of regions and a remaining portion of the data elements and a second parity value to a subset of the plural number of regions. The regions can comprise semiconductor dies in a flash memory, and the distributed storage space can be a garbage collection unit formed using one erasure block from each flash die.

Providing additional parity for non-standard sized parity data sets

Apparatus and method for managing entropy in a cryptographic processing system, such as but not limited to a solid-state drive (SSD). In some embodiments, a processing device is operated to transfer data between a host device and a non-volatile memory (NVM). In response to the detection of a power down event associated with the processing device, entropy associated with the power down event is collected and stored in a memory. Upon a subsequent reinitialization of the processing device, the entropy is conditioned and used as an input to a cryptographic function to subsequently transfer data between the host device and the NVM. In some embodiments, the entropy is obtained from the state of a hardware timer that provides a monotonically increasing count for timing control. In other embodiments, the entropy is obtained from a RAID buffer used to store data to a die set of the NVM.

Collection of uncorrelated entropy during a power down sequence

A data storage system can connect a plurality of remote hosts to a plurality of die sets resident in a semiconductor memory. Execution of at least one data access command addressed by a remote host of the plurality of remote hosts can occur prior to a power interruption event being detected for at least one die set of the plurality of die sets. User-generated data associated with the at least one data access command may then be flushed to a predetermined location responsive to an available resource budget associated with the power interruption event.

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Louisville, CO, United States of America

Kyumsung Lee