IN-MEMORY HASH ENTRIES AND HASHES USED TO IMPROVE KEY SEARCH OPERATIONS FOR KEYS OF A KEY VALUE STORE

    公开(公告)号:US20230350810A1

    公开(公告)日:2023-11-02

    申请号:US17732098

    申请日:2022-04-28

    申请人: NetApp Inc.

    IPC分类号: G06F12/1018

    CPC分类号: G06F12/1018

    摘要: Techniques are provided for implementing a hash building process and an append hash building process. The hash building process builds in-memory hash entries for bins of keys stored within sorted logs of a log structured merge tree used to store keys of a key-value store. The in-memory hash entries can be used to identify the starting locations of bins of keys within the log structured merge tree so that a key within a bin can be searched for from the starting location of the bin as opposed to having to search the entire log structured merge tree. The append hash building process builds two hashes that can be used to more efficiently locate keys and/or ranges of keys within an unsorted append log that would otherwise require a time consuming binary search of the entire append log.

    Defragmentation for log structured merge tree to improve read and write amplification

    公开(公告)号:US11971859B2

    公开(公告)日:2024-04-30

    申请号:US17732046

    申请日:2022-04-28

    申请人: NetApp Inc.

    CPC分类号: G06F16/1748 G06F16/182

    摘要: Techniques are provided for implementing a defragmentation process during a merge operation performed by a re-compaction process upon a log structured merge tree. The log structured merge tree is used to store keys of key-value pairs within a key-value store. As the log structured merge tree fills with keys over time, the re-compaction process is performed to merge keys down to lower levels of the log structured merge tree to re-compact the keys. Re-compaction can result in fragmentation because there is a lack of spatial locality of where the re-compaction operations re-writes the keys within storage. Fragmentation increases read and write amplification when accessing the keys stored in different locations within the storage. Accordingly, the defragmentation process is performed during a last merge operation of the re-compaction process in order to store keys together within the storage, thus reducing read and write amplification when accessing the keys.

    Network storage failover systems and associated methods

    公开(公告)号:US11216350B2

    公开(公告)日:2022-01-04

    申请号:US16855853

    申请日:2020-04-22

    申请人: NETAPP, INC.

    摘要: Failover methods and systems for a networked storage environment are provided. A metadata data structure is generated, before starting a replay of entries at a log stored in a non-volatile memory of a second storage node, during a failover operation initiated in response to a failure at a first storage node. The second storage node operates as a partner node of the first storage node, and the metadata structure stores a metadata attribute of each log entry. Furthermore, the metadata attribute of each log entry is persistently stored. The persistently stored metadata attribute is used to respond to a read request received during the replay by the second storage node, while a write request metadata attribute of a write request is used for executing the write request received by the second storage node during the replay.

    Methods for copy-free data migration across filesystems and devices thereof

    公开(公告)号:US10324652B2

    公开(公告)日:2019-06-18

    申请号:US15631296

    申请日:2017-06-23

    申请人: NetApp, Inc.

    IPC分类号: G06F3/06 G06F11/20

    摘要: Methods, non-transitory computer readable media, and computing devices that facilitate copy-free data migrations across filesystems. In a first step with this technology, a first set of filesystem metadata associated with a first filesystem is received. At least a portion of the first set of filesystem metadata is retrieved from a first data structure associated with the first filesystem. The first set of filesystem metadata includes a first identifier and a physical location associated with user data. A second identifier, associated with a second filesystem having a different addressing scheme than the first filesystem, is generated from at least the first identifier. A second set of filesystem metadata including the second identifier and the physical location is stored such that at least the second identifier is stored in a second data structure associated with the second filesystem.

    DEFRAGMENTATION FOR LOG STRUCTURED MERGE TREE TO IMPROVE READ AND WRITE AMPLIFICATION

    公开(公告)号:US20240281411A1

    公开(公告)日:2024-08-22

    申请号:US18648989

    申请日:2024-04-29

    申请人: NetApp, Inc.

    IPC分类号: G06F16/174 G06F16/182

    CPC分类号: G06F16/1748 G06F16/182

    摘要: Techniques are provided for implementing a defragmentation process during a merge operation performed by a re-compaction process upon a log structured merge tree. The log structured merge tree is used to store keys of key-value pairs within a key-value store. As the log structured merge tree fills with keys over time, the re-compaction process is performed to merge keys down to lower levels of the log structured merge tree to re-compact the keys. Re-compaction can result in fragmentation because there is a lack of spatial locality of where the re-compaction operations re-writes the keys within storage. Fragmentation increases read and write amplification when accessing the keys stored in different locations within the storage. Accordingly, the defragmentation process is performed during a last merge operation of the re-compaction process in order to store keys together within the storage, thus reducing read and write amplification when accessing the keys.

    Network storage failover systems and associated methods

    公开(公告)号:US11269744B2

    公开(公告)日:2022-03-08

    申请号:US16855837

    申请日:2020-04-22

    申请人: NETAPP, INC.

    IPC分类号: G06F11/20 G06F11/14

    摘要: Failover methods and systems for a networked storage environment are provided. A filtering data structure and a metadata data structure are generated before starting a replay of a log stored in a non-volatile memory of a second storage node, during a failover operation initiated in response to a failure at a first storage node. The second storage node operates as a partner node of the first storage node to mirror at the log one or more write requests received by the first storage node prior to the failure, and data associated with the one or more write requests. The filtering data structure identifies each log entry and the metadata structure stores a metadata attribute of each log entry. The filtering data structure and the metadata structure are used for providing access to a logical storage object during the log replay from the second storage node.

    NETWORK STORAGE FAILOVER SYSTEMS AND ASSOCIATED METHODS

    公开(公告)号:US20210334182A1

    公开(公告)日:2021-10-28

    申请号:US16855853

    申请日:2020-04-22

    申请人: NETAPP, INC.

    摘要: Failover methods and systems for a networked storage environment are provided. A metadata data structure is generated, before starting a replay of entries at a log stored in a non-volatile memory of a second storage node, during a failover operation initiated in response to a failure at a first storage node. The second storage node operates as a partner node of the first storage node, and the metadata structure stores a metadata attribute of each log entry. Furthermore, the metadata attribute of each log entry is persistently stored. The persistently stored metadata attribute is used to respond to a read request received during the replay by the second storage node, while a write request metadata attribute of a write request is used for executing the write request received by the second storage node during the replay.

    NETWORK STORAGE FAILOVER SYSTEMS AND ASSOCIATED METHODS

    公开(公告)号:US20210334180A1

    公开(公告)日:2021-10-28

    申请号:US16855870

    申请日:2020-04-22

    申请人: NETAPP, INC.

    摘要: Failover methods and systems for a networked storage environment are provided. In one aspect, a read request associated with a first storage object is received, during a replay of entries of a log stored in a non-volatile memory of a second storage node for a failover operation initiated in response to a failure at a first storage node. The second storage node operates as a partner node of the first storage node. The read request is processed using a filtering data structure that is generated from the log prior to the replay and identifies each log entry. The read request is processed when the log does not have an entry associated with the read request, and when the filtering data structure includes an entry associated with the read request, the requested data is located at the non-volatile memory.