公开(公告)号：US20220353519A1

公开(公告)日：2022-11-03

申请号：US17868597

申请日：2022-07-19

Applicant: Kioxia Corporation

Inventor： Daisuke YASHIMA ,  Masato SUMIYOSHI ,  Keiri NAKANISHI ,  Takashi MIURA ,  Kohei OIKAWA ,  Sho KODAMA ,  Youhei FUKAZAWA ,  Zheye WANG

IPC: H04N19/423 ,  H04N19/146 ,  H04N19/13

Abstract: According to one embodiment, a memory system includes a frequency value update unit, a first intra-group rearranging unit, a second intra-group rearranging unit, and a routing unit. The frequency value update unit adds a first value to each of one or more first frequency values that are associated with one or more first symbols, respectively, in one or more entries in a table. The first intra-group rearranging unit rearranges first entries, which belong to a first group, using frequency values in the first entries. The second intra-group rearranging unit rearranges second entries, which belong to a second group lower than the first group, using frequency values. The routing unit rearranges at least one of the first entries and at least one of the second entries.

公开(公告)号：US20220269416A1

公开(公告)日：2022-08-25

申请号：US17304025

申请日：2021-06-14

Applicant: Kioxia Corporation

Inventor： Sho KODAMA ,  Keiri NAKANISHI ,  Masato SUMIYOSHI ,  Zheye WANG ,  Kohei OIKAWA ,  Youhei FUKAZAWA ,  Daisuke YASHIMA ,  Takashi MIURA

IPC: G06F3/06 ,  H03M7/30

Abstract: According to one embodiment, a memory system includes a compressor configured to output second data obtained by compressing input first data and a non-volatile memory to which third data based on the second data output from the compressor is written. The compressor includes a dictionary coding unit configured to perform dictionary coding on the first data, an entropy coding unit configured to perform entropy coding on the result of the dictionary coding, a first calculation unit configured to calculate compression efficiencies of the dictionary coding and the entropy coding, and a first control unit configured to control an operation of at least one of the dictionary coding unit and the entropy coding unit based on the compression efficiencies and a power reduction level.

公开(公告)号：US20220187994A1

公开(公告)日：2022-06-16

申请号：US17471107

申请日：2021-09-09

Applicant: Kioxia Corporation

Inventor： Youhei FUKAZAWA ,  Kohei OIKAWA ,  Sho KODAMA ,  Keiri NAKANISHI ,  Takashi MIURA ,  Daisuke YASHIMA ,  Masato SUMIYOSHI ,  Zheye WANG

IPC: G06F3/06 ,  H03M7/30

Abstract: According to one embodiment, a compression device includes a first storage unit, a second storage unit, a calculation unit, and a comparison unit. The first storage unit stores addresses associated with hash values, respectively. The second storage unit includes storage areas specified by the addresses, respectively. The calculation unit determines a hash function to be used for first data in accordance with at least a part of the first data, and calculates a hash value using the hash function and at least a part of second data included in the first data. The comparison unit acquires third data from a storage area in the second storage unit specified by a first address, and compares the second data with the third data. The first address is stored in the first storage unit and is associated with the hash value.

公开(公告)号：US20220171724A1

公开(公告)日：2022-06-02

申请号：US17345651

申请日：2021-06-11

Applicant: Kioxia Corporation

Inventor： Keiri NAKANISHI ,  Kazuhiro HIWADA ,  Youhei FUKAZAWA

IPC: G06F13/18 ,  G06F13/16 ,  G06F9/54

Abstract: According to one embodiment, a memory system includes a first compression unit, a second compression unit, a non-volatile memory, a first decoding unit, a conversion unit and an output unit. The first compression unit is configured to output second data obtained by compressing first data. The second compression unit is configured to output third data obtained by compressing the second data. Fourth data based on the third data is written to the non-volatile memory. The first decoding unit is configured to decode the third data based on the fourth data to the second data. The conversion unit is configured to acquire fifth data by converting a format of the second data. The output unit is configured to output the fifth data to a host.