RAID is a storing technology that is very often used in nowadays systems and in general this storing volume provides more data security, availability and performance to the existing system. Being an important component of the system, the data storage volume and its performance affect directly the performance of the entire system. This is the motivation why it is convenient for us to improve as ...

Yoshitake Shinkai, Tetsutaro Maruyama, Naomi Yoshizawa Fujitsu Laboratories LTD. Kawasaki, Japan {shinkai, tetutaro, yszw}@flab.fujitsu.co.jp tel +81-44-754-2850 fax +81-44-754-2851 Abstract In this paper, we present a new software RAID technology called file RAID targeted at cluster environments where nodes share files through SAN (Storage Area Network). In it the file system manages separate ...

Many real-world applications like Video-On-Demand (VOD) and Web servers require prompt responses to access requests. However, with an explosive increase of data volume and the emerging of faster disks with higher power requirements, energy consumption of disk based storage systems has become a salient issue. To achieve energy-conservation and prompt responses simultaneously, in this paper we pr...

In this paper, we describe a design of a novel architecture for RAID that uses an SSD as a large cache to conserve energy. This approach stems from the fact that short term footprints are small enough to be efficiently managed within an SSD. More specifically, in this study, we consider two simple approaches to reduce the energy consumed in RAID. First, when a read happens in RAID, a copy of th...

RAID systems are widely deployed, both as standalone storage solutions and as the building blocks of modern virtualised storage platforms. An accurate model of RAID system performance is therefore critical to understanding storage system performance. To this end, this paper presents a queueing network-based model of RAID systems comprised of zoned disks and operating at RAID level 0-1 or 5. The...

{In this paper, we propose a highly reliable RAID architecture called a Dual-Crosshatch Disk Array. It uses the proposed interleaved 2d-parity scheme, a low overhead triple-erasure correcting parity organization. It is a hybrid approach of RAID-4 and RAID-5 with one dedicated parity group and another parity group using block interleaved data and parity. The results obtained from simulations ind...

Sector-Disk (SD) codes are erasure codes that address the mixed failure mode of current RAID systems. Rather than dedicate entire disks to erasure coding, as done in RAID-5, RAID-6 and Reed-Solomon coding, an SD code dedicates entire disks, plus individual sectors to erasure coding. The code then tolerates combinations of disk and sector errors, rather than solely disk errors. It has been an op...

This paper covers the fundamentals of I/O topics and an overview of RAID levels commonly found in an RDBMS environment. This paper will cover both the performance and fault tolerant properties of those RAID levels. By understanding the base concepts of I/O performance and technology used in your system you will be better able to size and configure your system. By understanding the various RAID ...

Of 8 patients with the short PR interval, normal QRS complex syndrome studied recently, 3 reported here displayed gaps in anterograde conduction. Atrial premature beats at decreasing coupling intervals conducted with minimal AH prolongation until a zone within the cardiac cycle was reached where conduction failed at a supra-Hisian level. Conduction resumed at earlier atrial coupling intervals a...