HYBRID TABLE IMPLEMENTATION BY USING BUFFER POOL AS PERMANENT IN-MEMORY STORAGE FOR MEMORY-RESIDENT DATA

• US 20140136510A1
• Filed: 11/13/2012
• Published: 05/15/2014
• Est. Priority Date: 11/13/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Parkkinen, Jarmo, Ruuth, Jarmo K., Soini, Petri U., Raatikka, Vilho T., Wolski, Antoni
• Granted Patent: US 10,114,908 B2
• Time in Patent Office: Days
• US Class Current: 707/711
• CPC Class Codes: G06F 16/119 Details of migration of file systems migration mechanisms in storage systems G06F3/0647
• CPC Class Codes: G06F 16/2272 Management thereof
• CPC Class Codes: G06F 16/901 Indexing; Data structures therefor; Storage structures for retrieval from the web G06F16/951

Abstract

Embodiments relate to a method, system, and computer program product for data management. An aspect includes a search index that is created for a database. The search index has a reference value of a first or a second type associating data to a storage location in a first memory or a second memory respectively. Responsive to a data retrieval request, data is accessed using the reference value from the first or the second memory. If there is a data migration between the first and second memory storage, the reference values are then recalculated and altered in the search index accordingly.

Claims

1. A data management method, comprising:

creating a search index for a database, said search index having a reference value of a first or a second type associating data to a storage location in a first memory or a second memory respectively;

responsive to a data retrieval request, accessing data using said reference value from said first or said second memory;

recalculating and altering said search index reference values based on data being migrated between said first and second memories.

2. The method of claim 1, wherein said first memory is in-memory storage and said second memory is disk memory storage.

3. The method of claim 2, further comprising using said reference value of said second type to access said particular data from a buffer pool if it is determined that said particular data is accessible from said buffer pool.

4. The method of claim 3, wherein said search index is a tree structured index.

5. The method of claim 4, wherein said tree has leaf nodes.

6. The method of claim 5, wherein said reference value of said first type is a page pointer to in-memory storage and said reference value of said second type is a page disk address.

7. The method of claim 6, wherein data access is provided using said page pointer or said page disk address according to said reference value provided.

8. The method of claim 5, wherein said leaf node indexing reference value for m-data in said permanent memory is a pointer to a page in said buffer and said leaf node indexing reference value for d-data is a disk address.

9. The method of claim 5, wherein said search index is a binary (B-tree) index structure.

10. The method of claim 6, wherein said index has a plurality of rows and columns and said rows have associated keys.

11. The method of claim 10, wherein said ordering of keys correspond to said ordering of rows.

12. The method of claim 8, wherein said migration from one component to another can be accomplished on a page replacement mechanism and said page is being generated by said buffer.

13. The method of claim 12, wherein said migration from one component to another can be accomplished on a least recently used basis.

14. The method of claim 8, wherein said migration from one component to another can be accomplished on an explicit basis.

15. A computer program product for data management, the computer program product comprising a computer readable storage medium having computer readable program code embodied therewith, said computer readable program code being executable by a computer to:

create a search index for a database, said search index having a reference value of a first or a second type associating data to a storage location in a first memory or a second memory respectively;

responsive to a data retrieval request, access data using said reference value from said first or said second memory;

recalculate and alter said search index reference values based on data being migrated between said first and second memories.

16. The computer program product of claim 15, wherein said index has a plurality or rows and columns and said index has associated keys corresponding to each row.

17. The computing program product of claim 16, wherein indexing granularity is a page and said index is enabled to have an additional on-page access.

18. The computer product of claim 17, wherein said first memory is in-memory storage and said second memory is disk memory storage.

19. The computer program product of claim 17, wherein said index is a sparse index and said d and m pages are identical in structure except for content.

20. A system comprising:

an in-memory storage;

a disk memory storage in processing communication said in-memory storage;

a buffer in processing communication with said in-memory and disk memory storage, said buffer including a buffer pool manager for handling buffer pool;

a database search engine having at least a processor for managing a data search index structure, said search index having reference values of a first or a second type such associating data to said in-memory and disk memory storage;

said reference value of first type being a page pointer to in-memory storage in said buffer pool and said reference value of second type being a page disk address to be processed by said buffer pool.