Title
DLSpace: Optimizing SSD Lifetime via An Efficient Distributed Log Space Allocation Strategy.
Abstract
Due to limited numbers of program/erase cycles (i.e., P/Es) of NAND Flash, excessive out-of-place update and erase-before-write operations wear out these P/Es during garbage collections, which adversely shorten solid state disk (i.e., SSD) lifetime. The log space in NAND Flash space of an SSD performs as an updated page ′s buffer, which lowers garbage-collection frequency while reducing consumption of P/Es to extend SSD lifetime. In this article, we propose DLSpace, a novel distributed log space allocation strategy named distributed log space, which divides log space into block-level log space and page-level log space to significantly optimize SSD lifetime. DLSpace′s log page space is dedicated to data pages in a data block. Such log page space only buffers page-update operations in this data block; thereby the use of log blocks for postponing garbage collection delays. DLSpace is conducive to fully utilizing pages in data and log blocks to avoid erasures of blocks with free pages. Consequently, DLSpace decreases write amplification by reducing excessive valid page-rewrite and block-erase operations under random-write-intensive workloads. We carried out quantitative research on the extension of SSD lifetime by virtue of three metrics (i.e., write amplification, the number of block-erase operations, and the delay time before the first garbage collection occurring). Experimental results reveal that compared with the existing traditional allocation strategy for log space (i.e., TLSpace), DLSpace reduces write amplification and the number of erase operations by up to 55.2% and 64.1% to the most extent, respectively. DLSpace also extends TLSpace′s delay time of garbage collections by 73.3% to optimize SSD lifetime.
Year
DOI
Venue
2019
10.1145/3284749
ACM Trans. Embedded Comput. Syst.
Keywords
Field
DocType
Distributed log space, lifetime, solid state disk, traditional log space, write amplification
Garbage,Computer science,Parallel computing,Write amplification,Block (data storage),NAND gate,Space allocation,Garbage collection,Solid-state
Journal
Volume
Issue
ISSN
17
6
1539-9087
Citations 
PageRank 
References 
0
0.34
48
Authors
4
Name
Order
Citations
PageRank
Hui Sun11113.46
Jianzhong Huang28719.32
Xiao Qin31836125.69
Changsheng Xie436666.54