Computer Engineering Commons^™

Towards Design And Analysis For High-Performance And Reliable Ssds, Qianbin Xia

Theses and Dissertations

NAND Flash-based Solid State Disks have many attractive technical merits, such as low power consumption, light weight, shock resistance, sustainability of hotter operation regimes, and extraordinarily high performance for random read access, which makes SSDs immensely popular and be widely employed in different types of environments including portable devices, personal computers, large data centers, and distributed data systems.

However, current SSDs still suffer from several critical inherent limitations, such as the inability of in-place-update, asymmetric read and write performance, slow garbage collection processes, limited endurance, and degraded write performance with the adoption of MLC and TLC techniques. To alleviate these …

Cloud Computing, Contractibility, And Network Architecture, Christopher S. Yoo

All Faculty Scholarship

The emergence of the cloud is heightening the demands on the network in terms of bandwidth, ubiquity, reliability, latency, and route control. Unfortunately, the current architecture was not designed to offer full support for all of these services or to permit money to flow through it. Instead of modifying or adding specific services, the architecture could redesigned to make Internet services contractible by making the relevant information associated with these services both observable and verifiable. Indeed, several on-going research programs are exploring such strategies, including the NSF’s NEBULA, eXpressive Internet Architecture (XIA), ChoiceNet, and the IEEE’s Intercloud projects.

Ultimate Codes: Near-Optimal Mds Array Codes For Raid-6, Zhijie Huang, Hong Jiang, Chong Wang, Ke Zhou, Yuhong Zhao

CSE Technical Reports

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 …

S-Code: Lowest Density Mds Array Codes For Raid-6, Zhijie Huang, Hong Jiang, Ke Zhou, Yuhong Zhao, Chong Wang

CSE Technical Reports

RAID, a storage architecture designed to exploit I/O parallelism and provide data reliability, has been deployed widely in computing systems as a storage building block. In large scale storage systems, in particular, RAID-6 is gradually replacing RAID-5 as the dominant form of disk arrays due to its capability of tolerating concurrent failures of any two disks. MDS (maximum distance separable) array codes are the most popular erasure codes that can be used for implementing RAID-6, since they enable optimal storage efficiency and efficient encoding and decoding algorithms. In this paper, we propose a new class of MDS array codes called …

Cloud Computing: Architectural And Policy Implications, Christopher S. Yoo

All Faculty Scholarship

Cloud computing has emerged as perhaps the hottest development in information technology. Despite all of the attention that it has garnered, existing analyses focus almost exclusively on the issues that surround data privacy without exploring cloud computing’s architectural and policy implications. This article offers an initial exploratory analysis in that direction. It begins by introducing key cloud computing concepts, such as service-oriented architectures, thin clients, and virtualization, and discusses the leading delivery models and deployment strategies that are being pursued by cloud computing providers. It next analyzes the economics of cloud computing in terms of reducing costs, transforming capital expenditures …

The Changing Patterns Of Internet Usage, Christopher S. Yoo

All Faculty Scholarship

The Internet unquestionably represents one of the most important technological developments in recent history. It has revolutionized the way people communicate with one another and obtain information and created an unimaginable variety of commercial and leisure activities. Interestingly, many members of the engineering community often observe that the current network is ill-suited to handle the demands that end users are placing on it. Indeed, engineering researchers often describe the network as ossified and impervious to significant architectural change. As a result, both the U.S. and the European Commission are sponsoring “clean slate” projects to study how the Internet might be …