PUD-LRU: An Erase-Efficient Write Buffer Management Algorithm for Flash Memory SSD

Flash memory SSDs pose a well-known challenge, that is, the erase-before-write problem. Researchers try to solve this inherent problem from two different angles by either designing sophisticated Flash Translation Layer (FTL) schemes to postpone and minimize erasures or designing flash-aware buffer management algorithms to absorb unnecessary erasures. Our experimental results show that buffer management inside SSD is necessary and indispensable. Further, based on our observation that TPC and some server workloads have strong temporal locality, this paper proposes a new flash-aware writebuffer management algorithm, called PUD-aware LRU algorithm (PUD-LRU), based on the Predicted average Update Distance (PUD) as the key block replacement criterion on top of log-block FTL schemes. The main idea of PUD-LRU is to differentiate blocks and judiciously destage blocks based on their frequency and recency so as to avoid the unnecessary erasures due to repetitive updates. To take advantage of the ...

• Type: Conference
• Year: 2010
• Where: MASCOTS
• Authors: Jian Hu, Hong Jiang, Lei Tian, Lei Xu
• Keywords: Buffer Management, Buffer Management Algorithm, Ftl Scheme, MASCOTS 2010, Modeling And Simulation