公开(公告)号：US20230315315A1

公开(公告)日：2023-10-05

申请号：US17708271

申请日：2022-03-30

Applicant: NetApp, Inc.

Inventor： Ritika ,  Jagadish Vasudeva ,  Vani Vully ,  Raj Kamal ,  Deepak Dangi ,  Parag Deshmukh

IPC: G06F3/06

CPC classification number: G06F3/064 ,  G06F3/0664 ,  G06F3/0659 ,  G06F3/0619 ,  G06F3/0689

Abstract: Systems and methods for reducing read application in a virtual storage system are provided. According to one embodiment, read amplification is reduced when AZCS compression is being utilized by avoiding restarting of a read process via a slow path via a RAID layer of the virtual storage system when a data block associated with a read request and obtained via a first fast path read has been found not to be compressed. Instead, a second fast path read may be performed to obtain the corresponding checksum. Alternatively, or additionally, heuristics may be used to predict the odds of the data block being compressed. For example, when information encoded within a PVBN of the data block that identifies the PVBN as being within a compressed AZCS zone has shown to be sufficiently/insufficiently predictive of the data block being compressed, then a flag may be set to enable/disable fast path reads.

公开(公告)号：US20140164825A1

公开(公告)日：2014-06-12

申请号：US14087319

申请日：2013-11-22

Applicant: NetApp, Inc.

Inventor： Tomislav Grcanac ,  Atul Goel ,  Jagadish Vasudeva ,  Gururaj Mj

IPC: G06F11/10

CPC classification number: G06F11/1088 ,  G06F11/1092 ,  G06F2211/104 ,  G06F2211/1088

Abstract: A data access request is received specifying a data block stored in a stripe of a parity group that includes a plurality of data storage devices to store data blocks and a parity storage device to store parity information for the data. The stripe includes a data block from each of the plurality of data storage devices and the stripe includes a parity block from the parity storage device. An error is detected in the data block specified by the data access request. The error is identified as a lost write error for the data block or a lost write error for the parity block. Identifying the error includes comparing a first storage device signature stored in a metadata field associated with the data block to a second storage device signature stored in a label block identifying a data storage device where the data block is stored.

Abstract translation: 接收指定存储在奇偶校验组的条带中的数据块的数据访问请求，所述奇偶校验组包括用于存储数据块的多个数据存储设备和用于存储数据的奇偶校验信息的奇偶校验存储设备。 条带包括来自多个数据存储设备中的每一个的数据块，并且条带包括来自奇偶校验存储设备的奇偶校验块。 在数据访问请求指定的数据块中检测到错误。 该错误被识别为数据块的丢失写入错误或奇偶校验块的丢失写入错误。 识别错误包括将存储在与数据块相关联的元数据字段中的第一存储设备签名与存储在标识存储数据块的数据存储设备的标签块中的第二存储设备签名进行比较。