Generating a checkpoint image for use with an in-memory database
AssigneeInternational Business Machines Corporation
InventorVilho T. Raatikka
Life of this patent
Estimating the term…
Abstract
Additional information is provided in a checkpoint image such that direct pointers can be included in the checkpoint image. Thus, an in-memory database management system can be restored from the checkpoint image in the event of a failure without causing any significant performance drawbacks to the database management system.
Claims10
An apparatus for generating a checkpoint image of an in-memory database system, the apparatus comprising:
- a computer comprising a processor;
- and
- instructions which are executable, using the processor of the computer, to perform:
- identifying one or more storage pages which have been modified but not incorporated into a previous checkpoint image;
- for each identified storage page, identifying a direct memory reference and its offset which correspond to a secondary storage location;
- for each identified storage page, identifying one or more leaf nodes of a primary index and a secondary index and a memory address of each database table row identified in each of the identified leaf nodes;
- for each of the identified memory addresses of each database table row, identifying a relation identifier of a database table of each of the database rows;
- and
- writing the identified direct memory references, the offsets, a relation identifier directory, and the identified leaf nodes of the primary and secondary indexes to a checkpoint image.
A computer program for generating a checkpoint image of an in-memory database system, the computer program embodied on a non-transitory computer-readable storage medium and comprising computer program code operable, when loaded into a computer system and executed, to perform:
- identifying one or more storage pages which have been modified but not incorporated into a previous checkpoint image;
- for each identified storage page, identifying a direct memory reference and its offset which correspond to a secondary storage location;
- for each identified storage page, identifying one or more leaf nodes of a primary index and a secondary index and a memory address of each database table row identified in each of the identified leaf nodes;
- for each of the identified memory addresses of each database table row, identifying a relation identifier of a database table of each of the database rows;
- and
- writing the identified direct memory references, the offsets, a relation identifier directory, and the identified leaf nodes of the primary and secondary indexes to a checkpoint image.
Dependencies are inferred from the claim text.