International Business Machines Corporation

Roger L Zheng

Matthew Albert Huras

Xun Xue

Serge Bourbonnais

Aamer U Sachedina

Keriley Kay Romanufa

Timothy Jon Vincent

Christian Zentgraf

James Liam Finnie

Stewart L Palmer

Sean W McKeough

Andrew David Buckler

David M Mooney

Austin D'costa

A method, system and computer program product is provided. The method includes identifying a large statement, writing the rows that are changed by the large statement into a set of files outside a database management system recovery log, and writing log records for the set of files to the database management system recovery log, such that the log records provide ordering of row changes made by the large statement. The log records include a log sequence number corresponding to a first row changed and a format and encoding used for the row changes. The method further includes streaming, by the one or more processors of the computer system, the set of files out-of-band by a replication capture process to a target database management system.

Replicating large statements with low latency

A system and method for managing shared resources is disclosed. The system includes a primary coherency processing unit which processes lock requests from a plurality of data processing hosts, the primary coherency processing unit also storing a first current lock state information for the plurality of data processing hosts, the first current lock state information including a plurality of locks held by the plurality of data processing hosts. The system further includes a standby coherency processing unit storing fewer locks than the primary coherency processing unit, the locks stored by the standby coherency processing unit being a subset of locks included in the first current lock state information, the standby coherency unit configured to perform a plurality of activities of the primary coherency processing unit using the subset of locks in response to a failure of the primary coherency processing unit.

Improving data availability during failure detection and recovery processing in a shared resource system

A system and method for managing deadlocks in a database management system (DBMS) for a demultiplexed database system. The DBMS supports applications that are capable of holding and retaining locks on database resources while disassociated from worker agents. The system and method includes an application scheduler for managing requests for access to the database, and a deadlock detector for identifying a deadlock. The application scheduler assigns one worker agent to an application requesting access to a database resource, assigns a flag to an application holding a lock on the database resource while disassociated from a worker agent, and in cooperation with the deadlock detector, resolves the deadlock between the application requesting access and the flagged application holding the lock.

System and method for deadlock management in database systems with demultiplexed connections

Growing community of inventors

Markham, Canada

Roger L Zheng