Phase-change memory (PCM) is a promising candidate as a storage medium to resolve the performance gap between
main memory and storage in battery-powered mobile computing systems. However, it is more expensive than flash memory, and thus
introduces a more serious storage capacity issue for low-cost solutions. This issue is further exacerbated by the fact that existing file
systems are usually designed to trade space utilization for performance over block-oriented storage devices. In this work, we propose
a multi-grained block management strategy to improve the space utilization of file systems over PCM-based storage systems. By
utilizing the byte-addressability and fast read/write feature of PCM, a methodology is proposed to dynamically allocate multiple sizes of
blocks to fit the size of each file, so as to resolve the space fragmentation issue with minimized space and management overheads. The
space utilization of file systems is analyzed with consideration of block sizes. A series of experiments was conducted to evaluate the
efficacy of the proposed strategy, and the results show that the proposed strategy can significantly improve the space utilization of file
systems.
關聯:
IEEE Transactions on Computers 65(6), pp.1831-1845
