Patent ID: 7100076

Claim:
A method of transferring a transaction processing workload of a primary process pair, the primary process pair having access to a stable storage volume for storing data items and a sequential log for storing transaction processing updates to data items, the method comprising: establishing a backup process pair for the primary process pair; while processing the transaction workload of the primary processing pair, transferring information from the primary process pair to the backup process pair, such that the backup process pair can takeover the workload of the primary processing pair if the primary process pair is not available to process the workload; maintaining a lock table whose entries indicate data items of the storage volume that are locked by transactions of the transaction processing workload; upon updating a data item in stable storage, writing update records to a log on the stable storage volume, the update records in the log including lock information relating to the update record; upon a failure of the primary process pair, switching to the backup process pair for transaction processing of the workload of the primary process pair and locking the stable storage volume; reading the log in stable storage to obtain the lock information contained therein; reconstructing a lock table for the backup process pair from the lock information read from the log; releasing the lock on the stable storage volume so that processing of the transaction processing workload of the primary process pair is continued by the backup process pair; and continuing the processing of the transaction workload by the backup process pair using the reconstructed lock table.