公开(公告)号：US20230359611A1

公开(公告)日：2023-11-09

申请号：US18354626

申请日：2023-07-18

Applicant: Dropbox, Inc.

Inventor： Preslav Le ,  Braden Walker ,  Leslie Tu ,  Tanay Lathia ,  Alexander Sosa ,  Lihao He

IPC: G06F16/23 ,  G06F16/22

CPC classification number: G06F16/2365 ,  G06F16/2272

Abstract: A consistency verification system that verifies data consistency in a content item management system. The system processes a write request. The write request includes a set of preconditions, a key, and data to write in a write operation. Processing the write request includes determining that the set of conditions are met, committing the write request at a commit time, and assigning a timestamp indicating the commit time to the write request. The system verifies data consistency associated with the write request. The verifying data consistency includes sending a replay request corresponding to the write request. The system determines whether results of the replay are consistent with results of the write request. Responsive to determining whether results of the replay are consistent with results of the write request, the system outputs information describing data inconsistency.

公开(公告)号：US11748333B2

公开(公告)日：2023-09-05

申请号：US17364606

申请日：2021-06-30

Applicant: Dropbox, Inc.

Inventor： Preslav Le ,  Braden Walker ,  Leslie Tu ,  Tanay Lathia ,  Alexander Sosa ,  Lihao He

IPC: G06F16/23 ,  G06F16/22

CPC classification number: G06F16/2365 ,  G06F16/2272

Abstract: A consistency verification system that verifies data consistency in a content item management system. The system maintains a plurality of verifiers for checking data consistency, each verifier comprising instructions for verifying consistency for a type of requests. The system may verify the original request by selecting a verifier from the plurality of verifiers based on a type of the original request. Using the selected verifier, the consistency verification system may send verification requests to the content item management system at a second timestamp that is a period of time after the original timestamp. The system may determine whether the second response is consistent with the first response. If the responses are not consistent, the system may output information describing data inconsistency. If the responses are consistent, the system may output results and perform further verifications to help ensure data accuracy.

公开(公告)号：US12050591B2

公开(公告)日：2024-07-30

申请号：US18354626

申请日：2023-07-18

Applicant: Dropbox, Inc.

Inventor： Preslav Le ,  Braden Walker ,  Leslie Tu ,  Tanay Lathia ,  Alexander Sosa ,  Lihao He

IPC: G06F16/23 ,  G06F16/22

CPC classification number: G06F16/2365 ,  G06F16/2272

Abstract: A consistency verification system that verifies data consistency in a content item management system. The system processes a write request. The write request includes a set of preconditions, a key, and data to write in a write operation. Processing the write request includes determining that the set of conditions are met, committing the write request at a commit time, and assigning a timestamp indicating the commit time to the write request. The system verifies data consistency associated with the write request. The verifying data consistency includes sending a replay request corresponding to the write request. The system determines whether results of the replay are consistent with results of the write request. Responsive to determining whether results of the replay are consistent with results of the write request, the system outputs information describing data inconsistency.

公开(公告)号：US20240111738A1

公开(公告)日：2024-04-04

申请号：US18540364

申请日：2023-12-14

Applicant: Dropbox, Inc.

Inventor： Anup Chenthamarakshan ,  Adam Faulkner ,  Ping Hu ,  Alexander Sosa

IPC: G06F16/215 ,  G06F16/22 ,  G06F16/23 ,  G06F16/28

CPC classification number: G06F16/215 ,  G06F16/22 ,  G06F16/2365 ,  G06F16/289 ,  H04L67/01

Abstract: An object management system (OMS) receives a plurality of objects to be stored. The OMS identifies a subset of objects associated with a same time period and a same namespace from the plurality of objects and generates a batch object comprising the subset of objects. The OMS issues a write request to store the batch object in an object storage system (OSS) and stores, for each object in the subset of objects, a data structure comprising an identifier of the batch object and a position of the object within the batch object. Upon receiving a read request for an object, the OMS determines, based on the data structure, whether the object is stored in the OSS and issues a read request to the OSS based on the identifier of the batch object and the position of the object within the batch, if the objects is stored in the OSS.

公开(公告)号：US20230004550A1

公开(公告)日：2023-01-05

申请号：US17364606

申请日：2021-06-30

Applicant: Dropbox, Inc.

Inventor： Preslav Le ,  Braden Walker ,  Leslie Tu ,  Tanay Lathia ,  Alexander Sosa ,  Lihao He

IPC: G06F16/23 ,  G06F16/22

Abstract: A consistency verification system that verifies data consistency in a content item management system. The system maintains a plurality of verifiers for checking data consistency, each verifier comprising instructions for verifying consistency for a type of requests. The system may verify the original request by selecting a verifier from the plurality of verifiers based on a type of the original request. Using the selected verifier, the consistency verification system may send verification requests to the content item management system at a second timestamp that is a period of time after the original timestamp. The system may determine whether the second response is consistent with the first response. If the responses are not consistent, the system may output information describing data inconsistency. If the responses are consistent, the system may output results and perform further verifications to help ensure data accuracy.

公开(公告)号：US11860836B2

公开(公告)日：2024-01-02

申请号：US17137092

申请日：2020-12-29

Applicant: Dropbox, Inc.

Inventor： Anup Chenthamarakshan ,  Adam Faulkner ,  Ping Hu ,  Alexander Sosa

IPC: G06F16/215 ,  G06F16/22 ,  G06F16/23 ,  G06F16/28 ,  H04L67/01

CPC classification number: G06F16/215 ,  G06F16/22 ,  G06F16/2365 ,  G06F16/289 ,  H04L67/01

Abstract: An object management system (OMS) receives a plurality of objects to be stored. The OMS identifies a subset of objects associated with a same time period and a same namespace from the plurality of objects and generates a batch object comprising the subset of objects. The OMS issues a write request to store the batch object in an object storage system (OSS) and stores, for each object in the subset of objects, a data structure comprising an identifier of the batch object and a position of the object within the batch object. Upon receiving a read request for an object, the OMS determines, based on the data structure, whether the object is stored in the OSS and issues a read request to the OSS based on the identifier of the batch object and the position of the object within the batch, if the objects is stored in the OSS.

公开(公告)号：US20220318227A1

公开(公告)日：2022-10-06

申请号：US17218103

申请日：2021-03-30

Applicant: Dropbox, Inc.

Inventor： Preslav Le ,  Daniel Adkins ,  Braden Walker ,  Robert Escriva ,  Tanay Lathia ,  Alexander Sosa

IPC: G06F16/23 ,  G06F16/22

Abstract: A content management system stores distributed data tables containing key-value pairs across a plurality of nodes and maintains a plurality of slices, with each slice corresponding to a contiguous key range across the data tables. The content management system may rebalance data among nodes by performing operations such as transferring, merging, or splitting slices. Each operation may be accomplished by performing multiple actions, and each action may cause change in states for slices. During an operation, slices may go through a series of state transitions. For each state transition, the content management system may record a timestamp when the state transition took place and the content management system may maintain a log that records timestamped state transitions associated with slices. The content management system may also perform various invariant checks and determine whether to reject or allow a state transition based on results of invariant checks.

公开(公告)号：US20220207005A1

公开(公告)日：2022-06-30

申请号：US17137092

申请日：2020-12-29

Applicant: Dropbox, Inc.

Inventor： Anup Chenthamarakshan ,  Adam Faulkner ,  Ping Hu ,  Alexander Sosa

IPC: G06F16/215 ,  G06F16/22 ,  G06F16/28 ,  G06F16/23

Abstract: An object management system (OMS) receives a plurality of objects to be stored. The OMS identifies a subset of objects associated with a same time period and a same namespace from the plurality of objects and generates a batch object comprising the subset of objects. The OMS issues a write request to store the batch object in an object storage system (OSS) and stores, for each object in the subset of objects, a data structure comprising an identifier of the batch object and a position of the object within the batch object. Upon receiving a read request for an object, the OMS determines, based on the data structure, whether the object is stored in the OSS and issues a read request to the OSS based on the identifier of the batch object and the position of the object within the batch, if the objects is stored in the OSS.