Google Inc.

Alfred Fuller

Rainer Hessmer

Vijay Kumar

Jianjun Chen

Steve Tsai

A method includes executing an initial instance of a change log process for a distributed system, each instance of the change log process configured to store a transaction history of transactions executed on the distributed system. The method also includes receiving transaction requests for executing corresponding transactions on the distributed system and determining a change log load based on the received transaction requests. The method includes executing at least one subsequent instance of the change log process when the change log load satisfied a threshold load. When multiple instances of the change log process are executing, the method includes ceasing execution of the at least one subsequent instance of the change log process and merging the transaction history of the initial instance of the change log process and the transaction history of the at least one subsequent instance of the change log process.

Real-time transactionally consistent change notifications

A method for database syncing is provided. The method includes receiving database change indicators indicating changes to a database. For each database change indicator, the method also includes determining whether the respective change to the database corresponds to a single change to a single version of the database, one of multiple changes to a common version of the database, or one of multiple changes to different versions of the database. The method further includes generating a change log compaction data structure comprising entries. Each entry includes an exact entry defining a corresponding single change to a corresponding single version of the database, a range entry defining corresponding multiple changes to a corresponding common version of the database, or an interval entry defining corresponding multiple changes to corresponding different versions of the database.

Database syncing

A method includes executing an initial instance of a change log process for a distributed system, each instance of the change log process configured to store, on memory hardware in communication with the data processing hardware, a transaction history of transactions executed on the distributed system. The method also includes receiving transaction requests for executing corresponding transactions on the distributed system and determining a change log load based on the received transaction requests. The method includes executing at least one subsequent instance of the change log process when the change log load satisfied a threshold load. When multiple instances of the change log process are executing, the method includes ceasing execution of the at least one subsequent instance of the change log process and merging the transaction history of the initial instance of the change log process and the transaction history of the at least one subsequent instance of the change log process.

Methods, systems, and apparatus are described for processing mutations for a remote database. In one aspect, a method includes receiving a log of database mutations from a client device, the log of database mutations indicating changes previously made to a client version of a database stored on the client device, and each database mutation specifying: an entity included in the database; an operation for the entity; and a client version number for the entity; identifying, in the log of database mutations, two or more database mutations that each specify a same client version number for a same entity; determining, based on a conflict resolution policy, that the two or more database mutations are eligible for collapsing; and collapsing the two or more database mutations into a single database mutation.

Growing community of inventors

San Carlos, CA, United States of America

Alfred Fuller