US 9,436,752 B2 · High availability via data services

Abstract

Application-level replication, the synchronization of data updates within a cluster of application servers, may be provided by having application servers themselves synchronize all updates to multiple redundant databases, precluding the need for database-level replication. This may be accomplished by first sending a set of database modifications requested by the transaction to a first database. Then a message may be placed in one or more message queues, the message indicating the objects inserted, updated, or deleted in the transaction. Then a commit command may be sent to the first database. The set of database modifications and a commit command may then be sent to a second database. This allows for transparent synchronization of the databases and quick recovery from a database failure, while imposing little performance or network overhead.

Claims10

Dependent claims

A method for failover from a failure of an application server during a transaction, the method comprising:

determining, using one or more processors, whether a message has been in a message queue for a predefined period of time;
discarding the message when a transaction ID for the message is not included in a transaction ID table in a first database and the message has been in the message queue for a predefined period of time;
replaying a set of database modifications to a second database when a transaction ID for the message is included in the transaction ID table in the first database but not in a transaction ID table in the second database;
determining whether the failure of the application server was detected during transmission of a cache synchronization message to a second application server or to a recovery server;
and
subsequent to detecting the failure of the application server during transmission of a cache synchronization message to the second application server or to the recovery server, transmitting the cache synchronization message to the second application server to update a cache of the second application server.

3 more elements

A system for failover from a failure of an application server during a transaction, the system comprising:

one or more processors;
and
a memory storing instructions that when executed by the one or more processors cause the system to:
detect a failure of an application server;
determine whether a message has been in a message queue for a predefined period of time;
discard the message when a transaction ID for the message is not included in a transaction ID table in a first database and the message has been in the message queue for a predefined period of time;
replay a set of database modifications to a second database when a transaction ID for said message is included in the transaction ID table in the first database but not in a transaction ID table in the second database;
determine whether the failure of the application server was detected during transmission of a cache synchronization message to a second application server or to a recovery server;
and
subsequent to detecting the failure of the application server during transmission of the cache synchronization message to the second application server or to the recovery server, transmitting the cache synchronization message to the second application server to update a cache of the second application server.

7 more elements

Dependencies are inferred from the claim text.

High availability via data services

Life of this patent

High availability via data services

Life of this patent

Abstract

Claims10