Abstract
With the rapid increasing capacity of flash memory, flash-aware indexing techniques are highly desirable for flash devices. The unique features of flash memory, such as the erase-before-write constraint and the asymmetric read/write cost, severely deteriorate the performance of the traditional B+-tree algorithm. In this paper, we propose an optimized indexing method, called lazy-update B+-tree, to overcome the limitations of flash memory. The basic idea is to defer the committing of update requests to the B+-tree by buffering them in a segment of main memory. They are later committed in groups so that the cost of each write operation can be amortized by a bunch of update requests. We identify a victim selection problem for the lazy-update B+-tree and develop two heuristic-based commit policies to address this problem. Simulation results show that the proposed lazy-update method, along with a well-designed commit policy, greatly improves the update performance of the traditional B+-tree while preserving the query efficiency.
Original language | English |
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Pages (from-to) | 509-522 |
Number of pages | 14 |
Journal | Journal of Computer Science and Technology |
Volume | 25 |
Issue number | 3 |
DOIs | |
Publication status | Published - May 2010 |
Scopus Subject Areas
- Software
- Theoretical Computer Science
- Hardware and Architecture
- Computer Science Applications
- Computational Theory and Mathematics
User-Defined Keywords
- B+-tree
- Flash memory
- Indexing
- Lazy update