公开(公告)号：US20150039847A1

公开(公告)日：2015-02-05

申请号：US13955734

申请日：2013-07-31

Applicant: Dropbox, Inc.

Inventor： Kevin P. Modzelewski

IPC: G06F3/06

CPC classification number: G06F3/065 ,  G06F3/0604 ,  G06F3/067 ,  G06F11/2058 ,  G06F11/2094 ,  H04L67/1095

Abstract: The disclosed embodiments relate to a system for managing replicated copies of data items in a storage system. During operation, the system obtains a current configuration of the storage system, wherein the current configuration specifies locations of replicated copies of data items. Next, the system analyzes the current configuration to identify possible movements of copies of data items among locations in the storage system. The system then assigns utilities to the identified movements, wherein a utility assigned to a movement reflects a change in reliability resulting from the movement. Finally, the system selects a utility-maximizing set of movements and performs the utility-maximizing set of movements to improve the reliability of the storage system.

Abstract translation: 所公开的实施例涉及用于管理存储系统中数据项的复制副本的系统。 在操作期间，系统获得存储系统的当前配置，其中当前配置指定数据项的复制副本的位置。 接下来，系统分析当前配置以识别存储系统中的位置之间的数据项副本的可能移动。 系统然后将实用程序分配给所识别的运动，其中分配给运动的实用程序反映由运动导致的可靠性的变化。 最后，系统选择效用最大化的一组运动，并执行效用最大化的运动集合，以提高存储系统的可靠性。

公开(公告)号：US20160139980A1

公开(公告)日：2016-05-19

申请号：US14540610

申请日：2014-11-13

Applicant: Dropbox, Inc.

Inventor： James Cowling ,  Kevin P. Modzelewski ,  Venkata Harish Mallipeddi

IPC: G06F11/10 ,  H03M13/00 ,  H03M13/05

CPC classification number: G06F11/1048 ,  H03M13/1515

Abstract: A data storage system stores sets of data blocks in extents located on storage devices. During operation, the system performs an erasure-coding operation by obtaining a set of source extents, wherein each source extent is stored on a different machine in the data storage system. The system also selects a set of destination machines for storing destination extents, wherein each destination extent is stored on a different destination machine. Next, the system performs the erasure-coding operation by retrieving data from the set of source extents, performing the erasure-coding operation on the retrieved data to produce erasure-coded data, and then writing the erasure-coded data to the set of destination extents on the set of destination machines. Finally, after the erasure-coding operation is complete, the system commits results of the erasure-coding operation to enable the set of destination extents to be accessed in place of the set of source extents.

Abstract translation: 数据存储系统存储位于存储设备上的盘区中的数据块集合。 在操作期间，系统通过获得一组源盘区进行擦除编码操作，其中每个源盘区存储在数据存储系统中的不同机器上。 该系统还选择一组用于存储目的地盘区的目的地机器，其中每个目的地盘区存储在不同的目的地机器上。 接下来，系统通过从源区间集合中检索数据，对检索的数据执行擦除编码操作来执行擦除编码操作，以产生擦除编码数据，然后将擦除编码数据写入目的地集合 目标机器组上的范围。 最后，在擦除编码操作完成之后，系统执行擦除编码操作的结果，以使得能够访问目标盘区的集合来代替该源盘区的集合。

公开(公告)号：US09619322B2

公开(公告)日：2017-04-11

申请号：US14540610

申请日：2014-11-13

Applicant: Dropbox, Inc.

Inventor： James Cowling ,  Kevin P. Modzelewski ,  Venkata Harish Mallipeddi

IPC: H03M13/00 ,  G06F11/10 ,  H03M13/15

CPC classification number: G06F11/1048 ,  H03M13/1515

Abstract: A data storage system stores sets of data blocks in extents located on storage devices. During operation, the system performs an erasure-coding operation by obtaining a set of source extents, wherein each source extent is stored on a different machine in the data storage system. The system also selects a set of destination machines for storing destination extents, wherein each destination extent is stored on a different destination machine. Next, the system performs the erasure-coding operation by retrieving data from the set of source extents, performing the erasure-coding operation on the retrieved data to produce erasure-coded data, and then writing the erasure-coded data to the set of destination extents on the set of destination machines. Finally, after the erasure-coding operation is complete, the system commits results of the erasure-coding operation to enable the set of destination extents to be accessed in place of the set of source extents.

公开(公告)号：US20150149500A1

公开(公告)日：2015-05-28

申请号：US14091119

申请日：2013-11-26

Applicant: Dropbox, Inc.

Inventor： James Cowling ,  Kevin P. Modzelewski

IPC: G06F17/30

CPC classification number: G06F11/2094 ,  G06F17/30212 ,  G06F17/3033

Abstract: The disclosed embodiments relate to a data storage system that facilitates efficiently recovering from storage device failures. Upon receiving a request to retrieve a data block from the data storage system, the system uses a hash that identifies the data block to look up a bucket and an associated cell containing the data block. Note that the bucket aggregates a large number of data blocks and is located in the associated cell that comprises a set of object storage devices (OSDs). Within the cell, the system uses the bucket to look up an OSD that contains the bucket in a local bucket database (BDB) for the cell. Within the OSD, the system uses the bucket and the hash to look up an offset and a length for the data block in a write-ahead log that stores data blocks for the bucket. Finally, the system returns the data block from the determined offset.

Abstract translation: 所公开的实施例涉及有助于从存储设备故障有效地恢复的数据存储系统。 在接收到从数据存储系统检索数据块的请求时，系统使用标识数据块的散列来查找存储桶和包含该数据块的关联单元。 注意，桶聚合大量的数据块并且位于包括一组对象存储设备（OSD）的关联小区中）。 在单元格内，系统使用存储桶在单元的本地存储桶数据库（BDB）中查找包含存储桶的OSD。 在OSD中，系统使用存储桶和散列来在存储数据块的预写日志中查找数据块的偏移量和长度。 最后，系统从确定的偏移量返回数据块。

公开(公告)号：US09405643B2

公开(公告)日：2016-08-02

申请号：US14091119

申请日：2013-11-26

Applicant: Dropbox, Inc.

Inventor： James Cowling ,  Kevin P. Modzelewski

IPC: G06F17/30 ,  G06F11/20

CPC classification number: G06F11/2094 ,  G06F17/30212 ,  G06F17/3033

Abstract: The disclosed embodiments relate to a data storage system that facilitates efficiently recovering from storage device failures. Upon receiving a request to retrieve a data block from the data storage system, the system uses a hash that identifies the data block to look up a bucket and an associated cell containing the data block. Note that the bucket aggregates a large number of data blocks and is located in the associated cell that comprises a set of object storage devices (OSDs). Within the cell, the system uses the bucket to look up an OSD that contains the bucket in a local bucket database (BDB) for the cell. Within the OSD, the system uses the bucket and the hash to look up an offset and a length for the data block in a write-ahead log that stores data blocks for the bucket. Finally, the system returns the data block from the determined offset.

Abstract translation: 所公开的实施例涉及有助于从存储设备故障有效地恢复的数据存储系统。 在接收到从数据存储系统检索数据块的请求时，系统使用标识数据块的散列来查找存储桶和包含该数据块的关联单元。 注意，桶聚合大量的数据块并且位于包括一组对象存储设备（OSD）的关联小区中）。 在单元格内，系统使用存储桶在单元的本地存储桶数据库（BDB）中查找包含存储桶的OSD。 在OSD中，系统使用存储桶和散列来在存储数据块的预写日志中查找数据块的偏移量和长度。 最后，系统从确定的偏移量返回数据块。

公开(公告)号：US09037762B2

公开(公告)日：2015-05-19

申请号：US13955734

申请日：2013-07-31

Applicant: Dropbox, Inc.

Inventor： Kevin P. Modzelewski

IPC: G06F15/16 ,  G06F3/06 ,  G06F11/20

CPC classification number: G06F3/065 ,  G06F3/0604 ,  G06F3/067 ,  G06F11/2058 ,  G06F11/2094 ,  H04L67/1095

Abstract: The disclosed embodiments relate to a system for managing replicated copies of data items in a storage system. During operation, the system obtains a current configuration of the storage system, wherein the current configuration specifies locations of replicated copies of data items. Next, the system analyzes the current configuration to identify possible movements of copies of data items among locations in the storage system. The system then assigns utilities to the identified movements, wherein a utility assigned to a movement reflects a change in reliability resulting from the movement. Finally, the system selects a utility-maximizing set of movements and performs the utility-maximizing set of movements to improve the reliability of the storage system.

Abstract translation: 所公开的实施例涉及用于管理存储系统中数据项的复制副本的系统。 在操作期间，系统获得存储系统的当前配置，其中当前配置指定数据项的复制副本的位置。 接下来，系统分析当前配置以识别存储系统中的位置之间的数据项副本的可能移动。 系统然后将实用程序分配给所识别的运动，其中分配给运动的实用程序反映由运动导致的可靠性的变化。 最后，系统选择效用最大化的一组运动，并执行效用最大化的运动集合，以提高存储系统的可靠性。