题目：A Horizontal-Diagonal Parity Code to Optimize I/O Load Balancing in RAID-6
报告人：何绪斌 美国弗吉尼亚联邦大学
地点：东五楼二楼210学术报告厅
时间：7月6日上午9:00

报告摘要：
　　With higher reliability requirements in clusters and data centers, RAID-6 has gained popularity due to its capability to tolerate concurrent failures of any two disks, which has been shown to be of increasing importance in large scale storage systems. Among various implementations of erasure codes in RAID-6, a typical set of codes known as Maximum Distance Separable (MDS) codes aim to offer data protection against disk failures with optimal storage efficiency. However, because of the limitation of horizontal parity or diagonal/anti-diagonal parities used in MDS codes, storage systems based on RAID-6 suffers from unbalanced I/O and thus low performance and reliability.
　　To address this issue, in this talk, we propose a new parity called Horizontal-Diagonal Parity (HDP), which takes advantages of both horizontal and diagonal/anti-diagonal parities. The corresponding MDS code, called HDP code, distributes parity elements uniformly in each strip to balance the I/O workloads. HDP also achieves high reliability via speeding up the recovery under single or double disk failure. Our analysis shows that HDP provides balanced I/O and higher reliability compared to other popular MDS codes.

何绪斌 简介：
　　Dr. Xubin He is currently an Associate Professor with tenure of Electrical and Computer Engineering at Virginia Commonwealth University. Dr. He received his PhD in Electrical and Computer Engineering from University of Rhode Island, USA in 2002 and both his MS and BS degrees in Computer Science from Huazhong University of Science and Technology, China, in 1997 and 1995, respectively. Prior to join VCU, Dr. He was an associate professor (2007-2010) and assistant professor (2002-2007) at Tennessee Tech University (TTU). His research interests include computer architecture, reliable and high availability storage systems and distributed computing. He has published more than 70 refereed articles in prestigious journals such as IEEE Transactions on Parallel and Distributed Systems (TPDS), Journal of Parallel and Distributed Computing (JPDC), ACM Transactions on Storage (ToS), and IEEE Transactions on Dependable and Secure Computing (TDSC), and at various international conferences, including USENIX ATC, IEEE/IFIP DSN, IEEE IPDPS, MSST, ICPP, MASCOTS, LCN, etc. Dr. He is the guest editor of a special issue on parallel and distributed computing for the International Journal of High Performance Computing and Networking, of which he also serves as an editor on board. He is the general co-chair for IEEE NAS’2009, program co-chair for MSST’2010, IEEE NAS’2008 and SNAPI’2007. Dr. He has served as a panelist for NSF, various chair roles and committee members for many professional conferences in the field. Dr. He was a recipient of the Ralph E. Powe Junior Faculty Enhancement Award in 2004 and the TTU Chapter Sigma Xi Research Award in 2010 and 2005, and TTU ECE Most Outstanding Teaching Faculty Award in 2010. He holds one U.S. patent. He is a senior member of the IEEE and a member of the IEEE Computer Society. Dr. He has received funds from U.S. National Science Foundation (NSF) totaling approximately $1.3million during the past 5 years. Further information about him can be found at: http://www.people.vcu.edu/~xhe2/.