Micro-benchmarking Flash Memory File-System Wear Leveling and Garbage Collection: A Focus on Initial State Impact

NAND flash memories are currently the de facto secondary storage technology in the embedded system domain thanks to their benefits mainly in terms of energy consumption, I/O performance, and data storage density. This Non-Volatile Memory (NVM) technology has even made substantial strides into enterprise storage systems. However, flash memories have particular constraints that are mainly the limited lifetime, the erase-before-write rule, and the write/erase operation granularity asymmetry. Those peculiarities are either handled in hardware, throughout a specific controller, or in software, with the help of a dedicated Flash File System (FFS). This paper presents a comprehensive study on the impact of different FFS implementations of wear leveling and garbage collection on flash memory performance and lifetime according to different initial states. This study is an attempt to push state-of-the-art work on FFSs by adding some flash memory specific features micro-benchmarking techniques.