公开(公告)号：US11588498B2

公开(公告)日：2023-02-21

申请号：US17472431

申请日：2021-09-10

Applicant: Kioxia Corporation

Inventor： Daisuke Yashima ,  Kohei Oikawa ,  Sho Kodama ,  Keiri Nakanishi ,  Masato Sumiyoshi ,  Youhei Fukazawa ,  Zheye Wang ,  Takashi Miura

IPC: H03M7/30 ,  G06F3/06 ,  G11C16/04

Abstract: According to one embodiment, a buffer stores first hash values and first complementary data. A first conversion unit converts consecutive characters in a second character string into second hash values and second complementary data. A search unit searches for consecutive first hash values from the buffer, and output a pointer. A selection unit selects consecutive first hash values and pieces of first complementary data from the buffer. A second conversion unit converts the consecutive first hash values into a third character string using the pieces of first complementary data. A comparison unit compares the second character string with the third character string to acquire a matching length. An output unit output the matching length with the pointer.

公开(公告)号：US20210294525A1

公开(公告)日：2021-09-23

申请号：US16942112

申请日：2020-07-29

Applicant: Kioxia Corporation

Inventor： Masato Sumiyoshi ,  Keiri Nakanishi ,  Takashi Miura ,  Kohei Oikawa ,  Daisuke Yashima ,  Sho Kodama ,  Youhei Fukazawa ,  Zheye Wang

IPC: G06F3/06 ,  H03M7/30

Abstract: A memory system including a storage device and a memory controller controlling the storage device and decoding an encoded data. The memory controller including: a history buffer storing a decoded data string; a history buffer read controller executing a read request to the history buffer; a decode executing section generating a first shaped data string based on the decoded data string read from the history buffer, generating a second shaped data string by refferring the first shaped data string before the first shaped data string being written back to the history buffer in response to the read request, and generating a decoded result using the first shaped data string and the second shaped data string.

公开(公告)号：US11909423B2

公开(公告)日：2024-02-20

申请号：US17693606

申请日：2022-03-14

Applicant: Kioxia Corporation

Inventor： Sho Kodama ,  Keiri Nakanishi ,  Daisuke Yashima

IPC: H03M7/30 ,  G06F3/06 ,  H03M7/40

CPC classification number: H03M7/3088 ,  G06F3/0608 ,  G06F3/0659 ,  G06F3/0679 ,  H03M7/40

Abstract: According to one embodiment, a compression circuit generates substrings from input data for (3+M) cycles, the input data being N bytes per cycle, a byte length of each substring being greater than or equal to (N×(1+M)+1); obtains a set of matches, each of the matches including at least one past input data which input past and corresponds to at least a part of each of the substrings; selects a subset of matches from the set of matches including the input data of one cycle; and outputs the subset of matches. M is zero or a natural number. N is a positive integer which is two or more.

公开(公告)号：US11777518B2

公开(公告)日：2023-10-03

申请号：US17653513

申请日：2022-03-04

Applicant: Kioxia Corporation

Inventor： Daisuke Yashima ,  Youhei Fukazawa ,  Sho Kodama ,  Keiri Nakanishi ,  Masato Sumiyoshi ,  Kohei Oikawa ,  Zheye Wang ,  Takashi Miura

IPC: H03M7/00 ,  H03M7/30

CPC classification number: H03M7/3088 ,  H03M7/6011

Abstract: According to one embodiment, a data compression device includes a dictionary match determination unit, an extended matching generator, a match selector and a match connector. The dictionary match determination unit searches for first past input data matching first new input data. The extended matching generator compares second past input data subsequent to the first past input data with second new input data subsequent to the first new input data. The match selector generates compressed data by replacing a part of the input data with match information output from the dictionary match determination unit or the extended matching generator. The match connector replaces a plurality of match information in the compressed data with single match information.

公开(公告)号：US20230289293A1

公开(公告)日：2023-09-14

申请号：US17940138

申请日：2022-09-08

Applicant: Kioxia Corporation

Inventor： Daisuke Yashima ,  Sho Kodama ,  Keiri Nakanishi ,  Masato Sumiyoshi ,  Youhei Fukazawa, ,  Zheye Wang ,  Kohei Oikawa ,  Takashi Miura

IPC: G06F12/0875

CPC classification number: G06F12/0875 ,  G06F2212/401 ,  G06F2212/1044

Abstract: According to one embodiment, a dictionary buffer stores dictionary data including a first substring and data before the first substring. A substring generator generates, from second input data, second substrings. A transformer transforms each of the second substrings into a hash value. A read processor reads the dictionary data, using a hash value transformed from a third substring among the second substrings. An acquisition unit compares a data string including the third substring and data before the third substring with the read dictionary data, and acquire first and second match lengths of the third and fourth substrings. A coded data generator generates coded data based on the acquired first and second match lengths.

公开(公告)号：US11714552B2

公开(公告)日：2023-08-01

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

CPC classification number: G06F3/0608 ,  G06F3/0625 ,  G06F3/0659 ,  G06F3/0679 ,  H03M7/3088

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：US11431995B2

公开(公告)日：2022-08-30

申请号：US17019941

申请日：2020-09-14

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 ,  H04N19/184

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：US11309909B2

公开(公告)日：2022-04-19

申请号：US17010013

申请日：2020-09-02

Applicant: Kioxia Corporation

Inventor： Youhei Fukazawa ,  Keiri Nakanishi ,  Sho Kodama ,  Masato Sumiyoshi ,  Kohei Oikawa ,  Daisuke Yashima ,  Takashi Miura ,  Zheye Wang

IPC: H03M7/00 ,  H03M7/40 ,  G06F40/126 ,  H03M7/30

Abstract: A compression device includes a dictionary based encoder, a second buffer, a comparator, and a compression data generator. The dictionary based encoder searches for second data at least partially matching first data from a first buffer, and acquires a first match position indicating a position of the second data in the first buffer and a match length indicating a matched length of the first and second data. The second buffer stores the previously acquired second match position with an index. The compression data generator generates first compressed data that includes the index assigned to the second match position in the second buffer and the match length when the first match position matches the second match position in the second buffer.

公开(公告)号：US12224778B2

公开(公告)日：2025-02-11

申请号：US18118732

申请日：2023-03-07

Applicant: Kioxia Corporation

Inventor： Keiri Nakanishi ,  Sho Kodama ,  Daisuke Yashima

IPC: H03M7/30 ,  H03M7/40 ,  G06F3/06

Abstract: According to one embodiment, a dictionary compressor for compressing input first data includes a buffer and a search unit. The buffer stores data input to the dictionary compressor prior to the first data. The search unit acquires, from the first data, partial data strings each having a first data length and having head positions in the first data, respectively, that are sequentially shifted by a second data length shorter than the first data length. The search unit performs search processes in parallel and acquires search results respectively corresponding to the search processes, the search processes searching the buffer to acquire respective match data strings that at least partially match the partial data strings, respectively.

公开(公告)号：US12212344B2

公开(公告)日：2025-01-28

申请号：US17941376

申请日：2022-09-09

Applicant: Kioxia Corporation

Inventor： Youhei Fukazawa ,  Keiri Nakanishi ,  Sho Kodama

IPC: H03M1/02 ,  H03M7/30 ,  H03M7/46

Abstract: According to one embodiment, an information processing apparatus includes a processor. The processor divides teacher data into character strings, calculates a score of each of the character strings based on at least an appearance frequency of each character string in the character strings, an appearance position of each of the character string in the character strings, and a length of each of the character strings, and determines a position of each of the character strings in a preset dictionary based on the score.