TECHNIQUES TO ENHANCE DATABASE PERFORMANCE

• US 20090254594A1
• Filed: 04/02/2008
• Published: 10/08/2009
• Est. Priority Date: 04/02/2008
• Status: Abandoned Application

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Burchall, Laurion D.
• Application Number:
  US12/060,872
• Publication Number:
  US 20090254594A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/1724 Details of de-fragmentation performed by the file system saving storage space on storage systems G06F3/0608; management of blocks in storage devices G06F3/064
• CPC Class Codes: G06F 16/2453 Query optimisation

Abstract

Techniques to enhance database performance are described. An apparatus may comprise an enhanced DBMS arranged to manage storage operations for tree data structures in a storage component. The enhanced DBMS may comprise a defragment detector module operative to identify a tree data structure as having a sequential data retrieval pattern. The enhanced DBMS may also comprise a defragment decision module communicatively coupled to the defragment detector module, the defragment decision module operative to determine whether to defragment the tree data structure, and output a defragment signal. The enhanced DBMS may further comprise a defragment manager module communicatively coupled to the defragment decision module, the defragment manager module operative to defragment the tree data structure in accordance with the defragment signal to reduce input/output operations for the storage component. Other embodiments are described and claimed.

Claims

1. A method, comprising:

identifying a tree data structure as having a sequential data retrieval pattern;

determining whether to defragment the tree data structure; and

defragmenting the tree data structure to reduce input/output operations for a storage component.

2. The method of claim 1, comprising determining whether to defragment the tree data structure based on a space usage density value or an extent reduction value.

3. The method of claim 1, comprising determining whether to defragment the tree data structure by comparing a space usage density value for the tree data structure with a defined threshold value.

4. The method of claim 1, comprising generating a space usage density value for the tree data structure by comparing a number of extents of contiguous pages in use by the tree data structure with a number of pages in the extents that are not currently in use by the tree data structure.

5. The method of claim 1, comprising determining whether to generate a space usage density value based on a page removal rate value representing a rate pages are removed from the tree data structure.

6. The method of claim 1, comprising determining whether to defragment the tree data structure by comparing an extent reduction value for the tree data structure with a defined threshold value.

7. The method of claim 1, comprising defragmenting the tree data structure using a left full merge, a left partial merge, or a move page merge.

8. The method of claim 1, comprising storing a tree data structure identifier and a location identifier for a defragmentation state machine on a periodic basis to restart defragmentation operations when interrupted.

9. The method of claim 1, comprising modifying a defragmentation rate for the tree data structure based on an instantaneous load for the storage component.

10. An article comprising a storage medium containing instructions that if executed enable a system to:

identify a tree data structure as having a sequential data retrieval pattern;

determine whether to defragment the tree data structure; and

defragment the tree data structure to reduce input/output operations for a storage component.

11. The article of claim 10, further comprising instructions that if executed enable the system to determine whether to defragment the tree data structure by comparing a space usage density value for the tree data structure with a defined threshold value.

12. The article of claim 10, further comprising instructions that if executed enable the system to determine whether to defragment the tree data structure by comparing an extent reduction value for the tree data structure with a defined threshold value.

13. The article of claim 10, further comprising instructions that if executed enable the system to store a tree data structure identifier and a location identifier for a defragmentation state machine on a periodic basis to restart defragmentation operations when interrupted.

14. The article of claim 10, further comprising instructions that if executed enable the system to modify a defragmentation rate for the tree data structure based on an instantaneous load for the storage component.

15. An apparatus, comprising:

an enhanced DBMS operative to manage storage operations for tree data structures in a storage component, the enhanced DBMS comprising;

a defragment detector module operative to identify a tree data structure as having a sequential data retrieval pattern;

a defragment decision module communicatively coupled to the defragment detector module, the defragment decision module operative to determine whether to defragment the tree data structure, and output a defragment signal; and

a defragment manager module communicatively coupled to the defragment decision module, the defragment manager module operative to defragment the tree data structure in accordance with the defragment signal to reduce input/output operations for the storage component.

16. The apparatus of claim 15, the defragment decision module operative to determine whether to defragment the tree data structure by comparing a space usage density value for the tree data structure with a defined threshold value.

17. The apparatus of claim 15, the defragment decision module operative to determine whether to defragment the tree data structure by comparing an extent reduction value for the tree data structure with a defined threshold value.

18. The apparatus of claim 15, the defragment manager module operative to store a tree data structure identifier and a location identifier for a defragmentation state machine on a periodic basis to restart defragmentation operations when interrupted.

19. The apparatus of claim 15, the defragment manager module operative to store a tree data structure identifier and a location identifier for a defragmentation state machine on a periodic basis, stop defragmentation operations at a defragment execution point prior to completely defragmenting the tree data structure, and restart the defragmentation operations using the tree data structure identifier and the location identifier for the defragmentation state machine at the defragment execution point.

20. The apparatus of claim 15, the defragment manager module operative to modify a defragmentation rate for the tree data structure based on an instantaneous load for the storage component.