公开(公告)号：US11182287B2

公开(公告)日：2021-11-23

申请号：US16787133

申请日：2020-02-11

Applicant: Kioxia Corporation

Inventor： Yoko Masuo ,  Yosuke Mitsumasu ,  Kazuya Kitsunai

IPC: G06F12/02 ,  G06F3/06

Abstract: According to one embodiment, a memory system includes a nonvolatile memory and a controller. The nonvolatile memory includes a plurality of blocks. The controller controls an operation of writing data to the nonvolatile memory and an operation of reading data to the nonvolatile memory. The controller includes a first processor and a second processor. The first processor executes a first process of creating one or more free blocks by transferring valid data in N blocks (where N is a natural number greater than or equal to two) to blocks of number less than N. The second processor executes a second process of transferring valid data including data which needs refresh in M blocks (where M is a natural number greater than or equal to one) to blocks of number less than or equal to M.

公开(公告)号：US12197724B2

公开(公告)日：2025-01-14

申请号：US18175468

申请日：2023-02-27

Applicant: Kioxia Corporation

Inventor： Hiromi Hoshino ,  Yoko Masuo

IPC: G06F3/06

Abstract: A memory system connectable to a host includes a nonvolatile memory and a controller. The nonvolatile memory includes physical blocks. The controller is configured to assign each of a plurality of block groups, each block group including a predetermined number or more of the physical blocks, to one of categories. The controller assigns block groups having a total capacity equal to a fraction of the overprovisioning capacity that is equal to a first threshold value, to the first category, and block groups having a total capacity equal to a remaining part of the overprovisioning capacity to the third category. When an overprovisioning ratio falls below a second threshold value, the controller reassigns one or more block groups in the third category to the first category.

公开(公告)号：US11500584B2

公开(公告)日：2022-11-15

申请号：US17014832

申请日：2020-09-08

Applicant: Kioxia Corporation

Inventor： Yoko Masuo

IPC: G06F3/06 ,  G06F12/02

Abstract: According to one embodiment, a memory system includes a nonvolatile memory and a controller. The nonvolatile memory includes blocks. The controller controls the nonvolatile memory. The controller acquires a write amount to the nonvolatile memory in a first period. The controller calculates an estimated amount of writing to the nonvolatile memory in the first period. The controller changes, when the write amount is larger than the estimated amount by a first threshold value or more, one or more parameters used for writing of data to the nonvolatile memory.

公开(公告)号：US12086429B2

公开(公告)日：2024-09-10

申请号：US18120733

申请日：2023-03-13

Applicant: Kioxia Corporation

Inventor： Yoko Masuo

IPC: G06F3/06

CPC classification number: G06F3/0625 ,  G06F3/0634 ,  G06F3/064 ,  G06F3/0659 ,  G06F3/0679

Abstract: According to one embodiment, the controller periodically executes a first operation. The controller selects a first mode or a second mode in the first operation. In a case where the first mode is selected, the controller reads pieces of data that are stored in contiguous memory locations, respectively, that are included in a first physical page or a second physical page. The first physical page is included in a first physical block of a first die. The second physical page is included in a second physical block of a second die. In a case where the second mode is selected, the controller reads first data stored in one memory location of the first physical page and second data stored in one memory location of the second physical page.

公开(公告)号：US11853204B2

公开(公告)日：2023-12-26

申请号：US18064135

申请日：2022-12-09

Applicant: Kioxia Corporation

Inventor： Yoko Masuo ,  Yosuke Mitsumasu

IPC: G06F3/06 ,  G06F12/02 ,  G06F17/18

CPC classification number: G06F12/0253 ,  G06F3/0608 ,  G06F3/0658 ,  G06F3/0679 ,  G06F17/18

Abstract: According to one embodiment, a memory system includes a controller which controls garbage collection for preparing one or more free blocks by writing valid data read from N blocks to one or more blocks of less than the N. The controller calculates a performance ratio between writing of data in response to a request from a host device and writing of data for the garbage collection in accordance with a data writable capacity remaining in a nonvolatile memory, calculates an average performance ratio from calculated performance ratios of M generations including a calculated latest performance ratio, and adjusts a performance cycle of the garbage collection by applying one of the calculated latest performance ratio and the calculated average performance ratio.

公开(公告)号：US11526436B2

公开(公告)日：2022-12-13

申请号：US16937661

申请日：2020-07-24

Applicant: Kioxia Corporation

Inventor： Yoko Masuo ,  Yosuke Mitsumasu

IPC: G06F3/06 ,  G06F12/02 ,  G06F17/18

Abstract: According to one embodiment, a memory system includes a controller which controls garbage collection for preparing one or more free blocks by writing valid data read from N blocks to one or more blocks of less than the N. The controller calculates a performance ratio between writing of data in response to a request from a host device and writing of data for the garbage collection in accordance with a data writable capacity remaining in a nonvolatile memory, calculates an average performance ratio from calculated performance ratios of M generations including a calculated latest performance ratio, and adjusts a performance cycle of the garbage collection by applying one of the calculated latest performance ratio and the calculated average performance ratio.