Efficient Implementation of RAID-5 Using Disk Based Read Modify Writes

Loading...
Thumbnail Image

View/Download File

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Efficient Implementation of RAID-5 Using Disk Based Read Modify Writes

Published Date

1997

Publisher

Type

Report

Abstract

Redundant Array of Inexpensive Disks (RAID) is often used to provide a fault tolerance capability for disk failures in database systems. An efficient implementation of small writes is the most important issue to achieve high throughput because most of writes in databases are small. The tradittional RAID implementation requires a RAID controller to construct parity blocks for writes (host based writes). An RAID implementation based on an exclusive-or (xor) engine in each disk may minimize link traffic and improve the response times for small writes. This is called disk based writes. However, many implementation issues have to resolved before the higher performance can be realized. We have observed that a straightforward implementation of disk based writes achieves only half of the potential throughput because of the interactions among commands. One of the implementation issues is to prevent a state of deadlock. A state of deadlock may occur when multiple disk based writes are executed simultaneously. The implementation issues addressed in this paper include how to prevent a state of deadlock, how to enhance cache replacement policy in disks, how to increase concurrency among disk basedd writes, and how to minimize the interactions of many commands. This paper investigates the effectiveness of disk based writes, and shows the performance comparison between a disk based write and a host based write in RAIDs. In a stress test, the aggregate throughput was increased, and the average command latency was reduced.

Keywords

Description

Related to

Replaces

License

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Suggested citation

Shim, Sangyup; Wang, Yuewei; Hsieh, Jenwei; Chang, Taisheng; Du, David H.C.. (1997). Efficient Implementation of RAID-5 Using Disk Based Read Modify Writes. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/215337.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.