• Journal of Digital Contents Society
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• v.14 no.1
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• pp.15-23
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• 2013

In response to the demands of large-scale data processing with low-power and new application, a storage system using SSD (Solid State Disk/Drive) with fast input-output performance instead of hard disc has appeared as storage device. Studies on methods to overcome specific problems of SSD such as various processing data units, out-place-update and limited delete count have been actively conducted. However, declining performance and stability have not been resolved yet when storing case specific data with small scale that causes frequent random write in hard disc or SSD. This thesis suggests a system structure that stores index requesting frequent random write in NVRAM capable of byte access by using characteristics such as byte unit fast read / write of NVRAM, non-volatile and smaller size of actual changed data size in index page than block size.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1696-1704
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• 2008

The conventional hard disk has been the dominant database storage system for over 25 years. Recently, hybrid systems which incorporate the advantages of flash memory into the conventional hard disks are considered to be the next dominant storage systems. Their features are satisfying the requirements like enhanced data I/O, energy consumption and reduced boot time, and they are sufficient to hybrid storage systems as major database storages. However, we need to improve traditional index management schemes based on B-Tree due to the relatively slow characteristics of hard disk operations, as compared to flashmemory. In order to achieve this goal, we propose a new index management scheme called FNC-Tree. FNC-Tree-based index management enhanced search and update performance by caching data objects in unused free area of flash leaf nodes to reduce slow hard disk I/Os in index access processes. Based on the results of the performance evaluation, we conclude that our scheme outperforms the traditional index management schemes.