公开(公告)号：US12235817B2

公开(公告)日：2025-02-25

申请号：US18475695

申请日：2023-09-27

Applicant: Lemon Inc. ,  Beijing Volcano Engine Technology Co., Ltd.

Inventor： Jiaxin Ou ,  Jingwei Zhang ,  Hao Wang ,  Hui Zhang ,  Ming Zhao ,  Yi Wang ,  Zhengyu Yang

IPC: G06F16/22 ,  G06F16/2455

Abstract: Systems and methods are provided for improved point querying of a database. The index values are separated from data and retained in cache memory to allow access without requiring a disk input/output (I/O) operation and thereby having less latency resulting from such disk I/O operations. The index values can be compressed using an algorithm such as Crit-Bit-Trie to allow storage of the index values in limited cache memory space. The index values can be selected for storage according to a least recently used approach when cache memory is insufficient to store all index values to maintain a hit rate for the cached portion and reduce the disk I/O operations.

公开(公告)号：US20240020167A1

公开(公告)日：2024-01-18

申请号：US18475763

申请日：2023-09-27

Applicant: Lemon Inc. ,  Beijing Volcano Engine Technology Co., Ltd.

Inventor： Jiaxin Ou ,  Hao Wang ,  Ming Zhao ,  Yi Wang ,  Zhengyu Yang

IPC: G06F9/50 ,  G06F11/14 ,  G06F16/18

CPC classification number: G06F9/5038 ,  G06F9/505 ,  G06F11/1435 ,  G06F16/1847

Abstract: By splitting data within a large LSM tree structure into smaller tree structures to reduce a number of layers in such a structure, write amplification factor (WAF) is efficiently reduced. By further classifying and labeling each I/O based on type, a lower-level filesystem is able to prioritize scheduling between different types of I/O to thereby facilitate stable latency for individual conjunction within the filesystem layer and for individual I/O operations.

公开(公告)号：US20240070135A1

公开(公告)日：2024-02-29

申请号：US18475695

申请日：2023-09-27

Applicant: Lemon Inc. ,  Beijing Volcano Engine Technology Co., Ltd.

Inventor： Jiaxin Ou ,  Jingwei Zhang ,  Hao Wang ,  Hui Zhang ,  Ming Zhao ,  Yi Wang ,  Zhengyu Yang

IPC: G06F16/22 ,  G06F16/2455

CPC classification number: G06F16/2228 ,  G06F16/2219 ,  G06F16/24552

Abstract: Systems and methods are provided for improved point querying of a database. The index values are separated from data and retained in cache memory to allow access without requiring a disk input/output (I/O) operation and thereby having less latency resulting from such disk I/O operations. The index values can be compressed using an algorithm such as Crit-Bit-Trie to allow storage of the index values in limited cache memory space. The index values can be selected for storage according to a least recently used approach when cache memory is insufficient to store all index values to maintain a hit rate for the cached portion and reduce the disk I/O operations.

公开(公告)号：US20240086362A1

公开(公告)日：2024-03-14

申请号：US18475725

申请日：2023-09-27

Applicant: Lemon Inc. ,  Beijing Volcano Engine Technology Co., Ltd.

Inventor： Hao Wang ,  Jiaxin Ou ,  Sheng Qiu ,  Yi Wang ,  Zhengyu Yang ,  Yizheng Jiao ,  Jingwei Zhang ,  Jianyang Hu ,  Yang Liu ,  Ming Zhao ,  Hui Zhang ,  Kuankuan Guo ,  Huan Sun ,  Yinlin Zhang

IPC: G06F16/13

CPC classification number: G06F16/134

Abstract: A key-value store and a file system are integrated together to provide improved operations. The key-value store can include a log engine, a hash engine, a sorting engine, and a garbage collection manager. The features of the key-value store can be configured to reduce the number of I/O operations involving the file system, thereby improving read efficiency, reducing write latency, and reducing write amplification issues inherent in the combined key-value store and file system.

公开(公告)号：US20240028566A1

公开(公告)日：2024-01-25

申请号：US18475746

申请日：2023-09-27

Applicant: Lemon Inc. ,  Beijing Volcano Engine Technology Co., Ltd.

Inventor： Sheng Qiu ,  Hao Wang ,  Zhengyu Yang ,  Yizheng Jiao ,  Jianyang Hu ,  Yang Liu ,  Jiaxin Ou ,  Huan Sun ,  Yinlin Zhang

IPC: G06F16/18 ,  G06F16/178 ,  G06F11/14

CPC classification number: G06F16/1815 ,  G06F16/178 ,  G06F16/1847 ,  G06F11/1407

Abstract: A file system particular for use with key-value stores is provided. The file system can operate in a user space instead of a kernel space. The file system can be an append-only file system. The file system can support use of solid state drives (SSDs) for storage, including zoned SSDs. The file system can include a file manager, a metadata manager, a task scheduler, a space allocator, and a collaborator for collaborating with a key-value store.

公开(公告)号：US20240020231A1

公开(公告)日：2024-01-18

申请号：US18475664

申请日：2023-09-27

Applicant: Lemon Inc. ,  Beijing Volcano Engine Technology Co., Ltd.

Inventor： Jiaxin Ou ,  Yi Wang ,  Jingwei Zhang ,  Zhengyu Yang

IPC: G06F12/02

CPC classification number: G06F12/0253 ,  G06F2212/7205

Abstract: Methods and systems for garbage collection and compaction for key-value engines in a data storage and communication system. The method includes determining disk capacity usage of the key-value engine and adjusting a garbage collection percentage threshold and a number of garbage collection threads based on whether the disk capacity usage of the key-value engine meets and/or exceeds predetermined disk capacity usage thresholds. The method may further include performing a periodic compaction process to consolidate one or more expired pages of one or more applications on a log-structured merge (LSM) tree by merging one or more layers into a last layer of the one or more expired pages to reduce data handling during an occurrence of the garbage collection.