Peripherals No More


Speaker:      Prof. Sam H. Noh, Ulsan National Institute of Science and Technology 
Time:           10:00am-11:00am  Nov.26.2021 

Host:            Prof. Chundong Wang

Link:                 Zoom:      会议号:991 7084 1803      密码:064581



We are in the midst of a dramatic change in what computer systems look like. The traditional memory hierarchy has recently been challenged with the advent of SSDs and persistent memory (PM). In this talk, I will share experiences and results from work that our NECSST lab at UNIST have been conducting regarding these changes. Firstly, I will present the use of PM as a buffer cache and how the persistent characteristics of PM can be exploited to improve storage I/O performance. By harnessing this PM layer, legacy file systems and traditional storage devices can be supported, while still performing comparably with state-of-the-art PM based file systems. Then I will revisit RAID. Existing All-Flash-Array (AFA) storage systems are susceptible to garbage collection (GC) at SSD- and AFA software-level. We accordingly take a spatial separation approach that partitions SSDs into the front-end SSDs dedicated to serve write requests and the back-end SSDs where GC is performed. Our approach with extensive evaluations guarantees that the storage bandwidth always matches the full network performance without being interfered by AFA-level GC for various workloads.


Sam H.(Hyuk) Noh received the PhD degree from University of Maryland, College Park, MD, in 1993. After spending a year as a faculty at the George Washington University, he moved to Hongik University, Seoul, Korea where he was faculty until 2015. Then he joined Ulsan National Institute of Science and Technology (UNIST) where he is a Professor and the inaugural Dean of the Graduate School of Artificial Intelligence in the College of Information and Biotechnology. Prof. Noh has served as General Chair, Program Chair, and Program Committee Member on a number of technical conferences and workshops including USENIX ATC, USENIX FAST, ACM Eurosys, ACM SOSP, ACM ASPLOS, USENIX OSDI, and WWW, among others. He has also been serving as Editor-in-Chief of the ACM Transactions on Storage since the summer of 2016. His current research interests include OS issues pertaining to computer systems with a focus on the use of new memory technologies such as flash memory and persistent memory. He is a Fellow of the ACM, a Senior Member of the IEEE, and a member of USENIX.