Title :
A study of background cleaning and data allocation for multi-channel SSDs
Author :
Ronghui Wang ; Ting Cao ; Ou Yang ; Nong Xiao ; Minxuan Zhang
Author_Institution :
Coll. of Comput., Nat. Univ. of Defense Technol., Changsha, China
Abstract :
Due to the idiosyncrasies of NAND flash memories, such as erase-before-write and bulk erase, SSDs employ an internal garbage collection process to recycle obsolete data to provide free spaces. To overlap the cleaning with I/O services in parallel units of multi-channel SSDs, a finer-granularity cleaning has been proposed, namely background cleaning. This method is not widely accepted for its reliability and wear-leveling problems. In this work, we study the background cleaning with different striping allocation policies, analyzing the SSD performance and write amplification with diverse cleaning units. Trace-driven simulations reveal that with certain striping allocation policies, finer-granularity cleaning can improve the SSD performance, as well as keep comparable cleaning efficiency, even without using the copy-back command.
Keywords :
NAND circuits; flash memories; storage management; I/O services; NAND flash memories; SSD performance; background cleaning; bulk erase; cleaning efficiency; copy-back command; data allocation; diverse cleaning units; erase-before-write; finer-granularity cleaning; internal garbage collection process; multichannel SSD; obsolete data recycle; parallel units; solid-state device; striping allocation policies; trace-driven simulations; write amplification; Cleaning; Flash memories; Hardware; Parallel processing; Performance evaluation; Resource management; Time factors; SSDs; allocation; background cleaning; multi-channel; write amplificatin;
Conference_Titel :
Instrumentation and Measurement, Sensor Network and Automation (IMSNA), 2013 2nd International Symposium on
Conference_Location :
Toronto, ON
DOI :
10.1109/IMSNA.2013.6743402
