公开(公告)号：US09892153B2

公开(公告)日：2018-02-13

申请号：US14578093

申请日：2014-12-19

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Yunrui Li ,  Mahesh Baburao Girkar ,  Hongyi Yao

IPC: G06F7/00 ,  G06F17/30 ,  G06F11/14 ,  G06F11/07 ,  G06F11/20

CPC classification number: G06F17/30368 ,  G06F3/06 ,  G06F3/0619 ,  G06F3/065 ,  G06F3/0689 ,  G06F11/0751 ,  G06F11/1435 ,  G06F11/1451 ,  G06F11/1471 ,  G06F11/2094 ,  G06F17/30356 ,  G06F17/30575 ,  G06F2201/80 ,  G06F2201/84

Abstract: Techniques are described that determine occurrences of lost write by comparing version identifiers of corresponding replica data blocks and checkpoints of data files that include the data blocks. A method determines lost writes that may have occurred among a first set of data blocks and a second set of data blocks. Each data block in the first set of data blocks corresponds to a respective data block in the second set that is a version of data blocks in the first set. The data blocks in the first set and the second set are associated with version identifiers. The second set of data blocks is associated with a second checkpoint for which any version of a data block in the second set associated a version identifier below the second checkpoint has been acknowledged to a database server as having been written to persistent storage. The method proceed to determining the lost writes by determining that a data block in the first set and a data block in the second set satisfy criteria, such as the version identifier of the first data block is between the version identifier of the second data block and the second checkpoint.