Using a read scrub counter associated with a time tag to initiate a read scrub operation
AssigneeSanDisk Technologies LLC
InventorVarun Sharma
Life of this patent
Estimating the term…
Abstract
A read scrub management system of a data storage device maintains and updates information associated with one or more Cell Voltage threshold Distribution (CVD) time tags. Each time tag is associated with one or more memory blocks and includes information about operating parameters associated with the memory blocks. Each time tag also includes its own read scrub counter. The read scrub management system increments the read scrub counter associated with a particular time tag each time one or more memory blocks associated with the particular time tag are accessed. When the read scrub counter reaches or exceeds a threshold value, the read scrub management system initiates a read scrub operation on the memory block(s) associated with the particular time tag.
Claims20
A method, comprising:
- receiving a read request from a host device;
- identifying one or more memory blocks of one or more memory dies of a non-volatile storage device associated with the read request;
- identifying a time tag associated with the identified one or more memory blocks, the time tag being associated with one or more operating parameters and a read scrub counter;
- incrementing the read scrub counter associated with the time tag;
- determining whether the read scrub counter associated with the time tag exceeds a threshold value;
- and
- initiating a read scrub operation on the one or more memory blocks associated with the time tag based, at least in part, on determining the read scrub counter associated with the time tag exceeds the threshold value.
A non-volatile data storage device, comprising:
- a controller;
- and
- one or more memory dies associated with the controller, wherein the controller is operable to:
- receive a read request;
- identify a memory block of at least one memory die of the one or more memory dies associated with the read request;
- identify a particular time tag from a plurality of time tags associated with the memory block, each time tag of the plurality of time tags being associated with one or more operating parameters and a respective read scrub counter;
- increment the read scrub counter associated with the particular time tag;
- determine whether the read scrub counter associated with the particular time tag exceeds a threshold value;
- and
- initiate a read scrub operation on the memory block associated with the particular time tag based, at least in part, on a determination that the read scrub counter associated with the particular time tag exceeds the threshold value.
A non-volatile data storage device, comprising:
- control means;
- data storage means divided into a plurality of memory blocks;
- read parameter tracking means, the read parameter tracking means being associated with one or more operating parameters and including a counting means for counting a number of times a subset of memory blocks from the plurality of memory blocks have been accessed;
- and
- read scrub operation means, the read scrub operation means initiating a read scrub operation on a memory block of the plurality of memory blocks associated with the read parameter tracking means.
Dependencies are inferred from the claim text.