Computer Science and Engineering, Department of


Date of this Version

Summer 2014


As modern storage systems have grown in size and complexity, RAID-6 is poised to replace RAID-5 as the dominant form of RAID architectures due to its ability to protect against double disk failures. Many excellent erasure codes specially designed for RAID-6 have emerged in recent years. However, all of them have limitations. In this paper, we present a class of near perfect erasure codes for RAID-6, called the Ultimate codes. These codes encode, update and decode either optimally or nearly optimally, regardless of what the code length is. This implies that utilizing these codes we can build highly efficient and scalable RAID-6 systems. The performance analysis shows that the Ultimate codes outperform all the existing representative RAID-6 codes in encoding and decoding. Because of these unique advantages of the Ultimate codes, we anticipate them to become a preferred choice of the RAID-6 implementers.