RAID: Redundant Arrays of Independent Disks

Size: px
Start display at page:

Download "RAID: Redundant Arrays of Independent Disks"

Transcription

1 RAID: Redundant Arrays of Independent Disks Dependable Systems Dr.-Ing. Jan Richling Kommunikations- und Betriebssysteme TU Berlin Winter 2012/2013

2 RAID: Introduction Redundant array of inexpensive disks or: Redundant array of independent disks Redundancy by spreading data across several disks Tolerating disk failures Needs at least two disks I/O performance increased by parallel access Caution: Relation between disks and controllers Originally by Patterson et. al. 1988: 6 types Here: Original types and commonly used variations n always represents the number of disks necesssary to get n times the capacity of a single disk 8 2 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

3 RAID 0 (I) RAID 0 A D G B E H C F Disk 1 Disk 2 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

4 RAID 0 (II) Striped array with no fault-tolerance Requires n disks Advantages High performance (theoretically: n-times of single disk) Simple design Disadvantages No fault-tolerance Reliability lower than for single disk Failure of one disk leads to complete data loss Use cases Storing temporary data with need for very high bandwidth Video production Compilation of large software projects 8 4 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

5 RAID 1 (I) RAID 1 A B A B Disk 1 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

6 RAID 1 (II) Mirroring of data Requires 2n disks Advantages One write or two reads in parallel Increased read performance (similar RAID 0) Simple design Tolerates failure of one disk No reconstruction of data necessary Disadvantages High overhead (100%) Use cases Applications requiring very high reliability Usually used for smaller amount of data 8 6 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

7 RAID 2 (I) RAID 2 A E B F C G D H ECC A-D 1 ECC A-D 2 ECC A-D 3 ECC E-H 1 ECC E-H 2 ECC E-H 3 Disk 1 Disk 2 Disk 3 Disk 4 Disk 5 Disk 6 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

8 RAID 2 (II) Using hamming code ECC to spread data among disks Word-wise ECC Number of disks depends on code Advantages Design simpler than RAID 5 Correction of single disk failure High data rates Disadvantages High overhead (decreases with number of disks) High entry cost No commercial implementation Use cases Not used in industry 8 8 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

9 RAID 3 (I) RAID 3 bytewise parity generation A D B E C F Parity A-C Parity D-F Disk 1 Disk 2 Disk 3 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

10 RAID 3 (II) Stripe set with additional disk for bytewise parity Requires n + 1 disks Advantages High data rates Low overhead Disk failure has low impact on performance Disadvantages Complex design Transaction rate equals single disk Unequal distribution of accesses to disks (parity disk is accessed much more often) Use cases Applications requiring high reliability Rarely used today 8 10 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

11 RAID 4 (I) RAID 4 blockwise parity generation A D B E C F Parity A-C Parity D-F Disk 1 Disk 2 Disk 3 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

12 RAID 4 (II) Similar to RAID 3 but using blockwise parity instead of byteor wordwise Requires n + 1 disks Advantages Similar to RAID 3 Disadvantages Similar to RAID 3 Use cases Applications requiring high reliability Rarely used today 8 12 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

13 RAID 5 (I) RAID 5 blockwise parity generation A Parity D-F G B D Parity G-I C E H Parity A-C F I Disk 1 Disk 2 Disk 3 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

14 RAID 5 (II) Striping with distributed / interleaving parity Parity is spread over disks Requires n + 1 disks Advantages High data rates Low overhead Equally distributed accesses Disadvantages Disk failure has medium impact on performance Complex design Complex rebuild Use cases Applications requiring high reliability Most versatile RAID level Most often used today 8 14 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

15 RAID 6 (I) RAID 6 blockwise parity generation 1 blockwise parity generation 2 A Parity 2 C-D Parity 1 E-F B C Parity 2 E-F Parity 1 A-B D E Parity2 A-B Parity 1 C-D F Disk 1 Disk 2 Disk 3 Disk Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

16 RAID 6 (II) Similar to RAID 5 but using two different parity algorithms to generate two sets of parity blocks Parity is spread over disks Requires n + 2 disks Advantages Higher reliability than RAID 5 High data rates Low overhead Equally distributed accesses Disadvantages Lower write performance Higher overhead Complex design High controller overhead Use cases Applications requiring high reliability Starts replacing RAID 5 in a lot of applications 8 16 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

17 Variations and Other Aspects Nested RAID levels RAID 1+0 RAID 0+1 Implementation issues Hardware-RAID Software-RAID RAID-implementations found on some mainboards Performance considerations 8 17 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

18 RAID 1+0 (I) RAID 1+0 A C A C B D B D Disk 1 Disk 2 Disk 3 Disk 4 Mirror 1 Mirror Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

19 RAID 1+0 (II) Stripeset of mirrors Sometimes called RAID 10 Requires 2n disks Advantages Combination of advantages of RAID 1 (redundancy) and RAID 0 (performance) Simple design High data rates Disadvantages High overhead Use cases Applications requiring high performance and high reliability 8 19 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

20 RAID 0+1 (I) RAID 0+1 A C B D A C B D Disk 1 Disk 2 Disk 3 Disk 4 Stripe set 1 Stripe set Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

21 RAID 0+1 (II) Mirrored stripesets Sometimes called RAID 01 Requires 2n disks Advantages High performance Tolerates single disk failure (becomes RAID 0) Simple design Disadvantages High overhead Use cases Applications requiring high performance and some reliability 8 21 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

22 RAID 1+0 vs. RAID 0+1 In case of four disks, which one is better? Goal: High reliability Modelling using reliability block diagrams Assumption: All disks have the same reliability Calculation: Exercise! 8 22 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

23 Hardware-RAID vs. Software-RAID Hardware-RAID RAID algorithm is calculated by controller or external device Operating system sees a single disk device No impact on performance of main processor RAID array usually only usable with the original controller or compatible Hardware design optimized for RAID usage Usually operates on whole disks Software-RAID RAID algorithm executed by OS (or one of its drivers) using main processor Performance of main processor is affected by RAID RAID-drivers creates array out of several devices RAID array can be used with other controllers that use the same drive geometry as long as driver is compatible Hardware usually not optimized for RAID usage (number of disks per controller, disks sharing I/O-channel, ) Usually operates on partitions 8 23 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

24 Mainboard-RAIDs A lot of modern mainboards features RAID -controllers Usually not hardware-raid RAID-algorithms are executed on main processor by driver using specialized hardware Acceleration by specialized hardware depends on implementation Extreme cases are pure software (cheap) and pure hardware implementations (expensive) Caution: Array usually cannot be used by mainboards of other types 8 24 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

25 Performance Considerations (I) Performance of RAID depends on all components along the data path Disk Controller and the topology of disks (shared bus vs. point-to-point) Bus system of computer (topology, bandwidth) I/O-performance of system Performance depends on weakest part! Example for bad design: Four EIDE disks delivering 80 MB/each Overall throughput: 320 MB/s Each pair shares a 100 MB/s PATA channel Overall throughput: 200 MB/s Each PATA channel is connected to a PCI controller Overall throughput: 133 MB/s PCI bus limits theoretical peak throughput Reality: Much slower (overhead, other devices use PCI too, ) Only one third of disk bandwidth is usable in parallel operation 8 25 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

26 Performance Considerations (II) Example for good design: Four SATA disks delivering 80 MB/each Overall throughput: 320 MB/s Each device uses a 1.5 Gbs SATA 1 link Overall throughput: 600 MB/s Two devices share a PCI-e x1 controller Overall throughput: 500 MB/s In parallel operation total overall disk bandwidth can be used Software-RAID: Performance of main processor Trade-off between performance needed for RAID and rest of system Hardware-RAID: Is the interface fast enough for the maximum bandwidth of chosen RAID configuration? 8 26 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

27 Spare disks Problem: Most RAID implementation have very low reliability in degraded mode Fast repair is necessary (human activity) Hardware-RAID and some Software-RAIDs: Hot swap is possible But: Low MTTR leads to high cost Solution: Spare disks Additional disk(s) not being part of array In case of failure controller uses spare disk instead of failed disk and starts reconstruction of array Results in intact array Spare disk is replaced later But: Using RAID with higher fault tolerance is better due to critical phase while reconstructing E.g., RAID 5 + Spare vs. RAID Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

28 RAID and Reliability (I) Calculation based on reliability block diagram Assumption (fault model): Disk fault results in read error Controller recognizes read error and locates faulty disk RAID continues to work in degrated mode Problem In reality, disk faults often result in errors only while accessing the data Faults on seldom used parts of disk may exist for a long time not resulting in an error Result: Risk for data loss increases as the next error forces rebuilding of RAID and hidden fault results in the second error Solution: Disk scrubbing 8 28 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

29 Disk Scrubbing Idea: Access all sectors of all disks of the RAID system at regular intervals Implemented by forced rebuilding of array Detects hidden faults (they result in error while accessing a disk) Administrator replaces disk Reduces probability of double disk error Good practice: Once per month Linux Software-RAID: echo check > /sys/block/mdx/md/sync_action 8 29 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

30 RAID and Reliability (II) Reliability does not only depend on disks Other components are important too Controller Power supply Cabling Cooling Problem: Single point of failure Detection requires detailled knowledge on configuration Hidden interfaces have to be considered 8 30 Dr.-Ing. Jan Richling Dependable Systems Winter 2012/2013

Click on the diagram to see RAID 0 in action

Click on the diagram to see RAID 0 in action Click on the diagram to see RAID 0 in action RAID Level 0 requires a minimum of 2 drives to implement RAID 0 implements a striped disk array, the data is broken down into blocks and each block is written

More information

systems' resilience to disk failure through

systems' resilience to disk failure through BY Shashwath Veerappa Devaru CS615 Aspects of System Administration Using Multiple Hard Drives for Performance and Reliability RAID is the term used to describe a storage systems' resilience to disk failure

More information

Dependable Systems. 9. Redundant arrays of. Prof. Dr. Miroslaw Malek. Wintersemester 2004/05 www.informatik.hu-berlin.de/rok/zs

Dependable Systems. 9. Redundant arrays of. Prof. Dr. Miroslaw Malek. Wintersemester 2004/05 www.informatik.hu-berlin.de/rok/zs Dependable Systems 9. Redundant arrays of inexpensive disks (RAID) Prof. Dr. Miroslaw Malek Wintersemester 2004/05 www.informatik.hu-berlin.de/rok/zs Redundant Arrays of Inexpensive Disks (RAID) RAID is

More information

Lecture 36: Chapter 6

Lecture 36: Chapter 6 Lecture 36: Chapter 6 Today s topic RAID 1 RAID Redundant Array of Inexpensive (Independent) Disks Use multiple smaller disks (c.f. one large disk) Parallelism improves performance Plus extra disk(s) for

More information

Definition of RAID Levels

Definition of RAID Levels RAID The basic idea of RAID (Redundant Array of Independent Disks) is to combine multiple inexpensive disk drives into an array of disk drives to obtain performance, capacity and reliability that exceeds

More information

Module 6. RAID and Expansion Devices

Module 6. RAID and Expansion Devices Module 6 RAID and Expansion Devices Objectives 1. PC Hardware A.1.5 Compare and contrast RAID types B.1.8 Compare expansion devices 2 RAID 3 RAID 1. Redundant Array of Independent (or Inexpensive) Disks

More information

RAID Level Descriptions. RAID 0 (Striping)

RAID Level Descriptions. RAID 0 (Striping) RAID Level Descriptions RAID 0 (Striping) Offers low cost and maximum performance, but offers no fault tolerance; a single disk failure results in TOTAL data loss. Businesses use RAID 0 mainly for tasks

More information

Hard Disk Drives and RAID

Hard Disk Drives and RAID Hard Disk Drives and RAID Janaka Harambearachchi (Engineer/Systems Development) INTERFACES FOR HDD A computer interfaces is what allows a computer to send and retrieve information for storage devices such

More information

RAID Levels and Components Explained Page 1 of 23

RAID Levels and Components Explained Page 1 of 23 RAID Levels and Components Explained Page 1 of 23 What's RAID? The purpose of this document is to explain the many forms or RAID systems, and why they are useful, and their disadvantages. RAID - Redundant

More information

Input / Ouput devices. I/O Chapter 8. Goals & Constraints. Measures of Performance. Anatomy of a Disk Drive. Introduction - 8.1

Input / Ouput devices. I/O Chapter 8. Goals & Constraints. Measures of Performance. Anatomy of a Disk Drive. Introduction - 8.1 Introduction - 8.1 I/O Chapter 8 Disk Storage and Dependability 8.2 Buses and other connectors 8.4 I/O performance measures 8.6 Input / Ouput devices keyboard, mouse, printer, game controllers, hard drive,

More information

RAID. RAID 0 No redundancy ( AID?) Just stripe data over multiple disks But it does improve performance. Chapter 6 Storage and Other I/O Topics 29

RAID. RAID 0 No redundancy ( AID?) Just stripe data over multiple disks But it does improve performance. Chapter 6 Storage and Other I/O Topics 29 RAID Redundant Array of Inexpensive (Independent) Disks Use multiple smaller disks (c.f. one large disk) Parallelism improves performance Plus extra disk(s) for redundant data storage Provides fault tolerant

More information

Education. Servicing the IBM ServeRAID-8k Serial- Attached SCSI Controller. Study guide. XW5078 Release 1.00

Education. Servicing the IBM ServeRAID-8k Serial- Attached SCSI Controller. Study guide. XW5078 Release 1.00 Education Servicing the IBM ServeRAID-8k Serial- Attached SCSI Controller Study guide XW5078 Release 1.00 May 2006 Servicing the IBM ServeRAID-8k Serial- Attached SCSI (SAS) Controller Overview The ServeRAID

More information

Reliability and Fault Tolerance in Storage

Reliability and Fault Tolerance in Storage Reliability and Fault Tolerance in Storage Dalit Naor/ Dima Sotnikov IBM Haifa Research Storage Systems 1 Advanced Topics on Storage Systems - Spring 2014, Tel-Aviv University http://www.eng.tau.ac.il/semcom

More information

File System & Device Drive. Overview of Mass Storage Structure. Moving head Disk Mechanism. HDD Pictures 11/13/2014. CS341: Operating System

File System & Device Drive. Overview of Mass Storage Structure. Moving head Disk Mechanism. HDD Pictures 11/13/2014. CS341: Operating System CS341: Operating System Lect 36: 1 st Nov 2014 Dr. A. Sahu Dept of Comp. Sc. & Engg. Indian Institute of Technology Guwahati File System & Device Drive Mass Storage Disk Structure Disk Arm Scheduling RAID

More information

CS 6290 I/O and Storage. Milos Prvulovic

CS 6290 I/O and Storage. Milos Prvulovic CS 6290 I/O and Storage Milos Prvulovic Storage Systems I/O performance (bandwidth, latency) Bandwidth improving, but not as fast as CPU Latency improving very slowly Consequently, by Amdahl s Law: fraction

More information

ES-1 Elettronica dei Sistemi 1 Computer Architecture

ES-1 Elettronica dei Sistemi 1 Computer Architecture ES- Elettronica dei Sistemi Computer Architecture Lesson 7 Disk Arrays Network Attached Storage 4"» "» 8"» 525"» 35"» 25"» 8"» 3"» high bandwidth disk systems based on arrays of disks Decreasing Disk Diameters

More information

Guide to SATA Hard Disks Installation and RAID Configuration

Guide to SATA Hard Disks Installation and RAID Configuration Guide to SATA Hard Disks Installation and RAID Configuration 1. Guide to SATA Hard Disks Installation... 2 1.1 Serial ATA (SATA) Hard Disks Installation... 2 2. Guide to RAID Configurations... 3 2.1 Introduction

More information

IBM ^ xseries ServeRAID Technology

IBM ^ xseries ServeRAID Technology IBM ^ xseries ServeRAID Technology Reliability through RAID technology Executive Summary: t long ago, business-critical computing on industry-standard platforms was unheard of. Proprietary systems were

More information

SSDs and RAID: What s the right strategy. Paul Goodwin VP Product Development Avant Technology

SSDs and RAID: What s the right strategy. Paul Goodwin VP Product Development Avant Technology SSDs and RAID: What s the right strategy Paul Goodwin VP Product Development Avant Technology SSDs and RAID: What s the right strategy Flash Overview SSD Overview RAID overview Thoughts about Raid Strategies

More information

Chapter 6. 6.1 Introduction. Storage and Other I/O Topics. p. 570( 頁 585) Fig. 6.1. I/O devices can be characterized by. I/O bus connections

Chapter 6. 6.1 Introduction. Storage and Other I/O Topics. p. 570( 頁 585) Fig. 6.1. I/O devices can be characterized by. I/O bus connections Chapter 6 Storage and Other I/O Topics 6.1 Introduction I/O devices can be characterized by Behavior: input, output, storage Partner: human or machine Data rate: bytes/sec, transfers/sec I/O bus connections

More information

RAID: Redundant Arrays of Inexpensive Disks this discussion is based on the paper: on Management of Data (Chicago, IL), pp.109--116, 1988.

RAID: Redundant Arrays of Inexpensive Disks this discussion is based on the paper: on Management of Data (Chicago, IL), pp.109--116, 1988. : Redundant Arrays of Inexpensive Disks this discussion is based on the paper:» A Case for Redundant Arrays of Inexpensive Disks (),» David A Patterson, Garth Gibson, and Randy H Katz,» In Proceedings

More information

Guide to SATA Hard Disks Installation and RAID Configuration

Guide to SATA Hard Disks Installation and RAID Configuration Guide to SATA Hard Disks Installation and RAID Configuration 1. Guide to SATA Hard Disks Installation...2 1.1 Serial ATA (SATA) Hard Disks Installation...2 2. Guide to RAID Configurations...3 2.1 Introduction

More information

DELL RAID PRIMER DELL PERC RAID CONTROLLERS. Joe H. Trickey III. Dell Storage RAID Product Marketing. John Seward. Dell Storage RAID Engineering

DELL RAID PRIMER DELL PERC RAID CONTROLLERS. Joe H. Trickey III. Dell Storage RAID Product Marketing. John Seward. Dell Storage RAID Engineering DELL RAID PRIMER DELL PERC RAID CONTROLLERS Joe H. Trickey III Dell Storage RAID Product Marketing John Seward Dell Storage RAID Engineering http://www.dell.com/content/topics/topic.aspx/global/products/pvaul/top

More information

technology brief RAID Levels March 1997 Introduction Characteristics of RAID Levels

technology brief RAID Levels March 1997 Introduction Characteristics of RAID Levels technology brief RAID Levels March 1997 Introduction RAID is an acronym for Redundant Array of Independent Disks (originally Redundant Array of Inexpensive Disks) coined in a 1987 University of California

More information

Introduction to I/O and Disk Management

Introduction to I/O and Disk Management Introduction to I/O and Disk Management 1 Secondary Storage Management Disks just like memory, only different Why have disks? Memory is small. Disks are large. Short term storage for memory contents (e.g.,

More information

Using RAID6 for Advanced Data Protection

Using RAID6 for Advanced Data Protection Using RAI6 for Advanced ata Protection 2006 Infortrend Corporation. All rights reserved. Table of Contents The Challenge of Fault Tolerance... 3 A Compelling Technology: RAI6... 3 Parity... 4 Why Use RAI6...

More information

Operating Systems. RAID Redundant Array of Independent Disks. Submitted by Ankur Niyogi 2003EE20367

Operating Systems. RAID Redundant Array of Independent Disks. Submitted by Ankur Niyogi 2003EE20367 Operating Systems RAID Redundant Array of Independent Disks Submitted by Ankur Niyogi 2003EE20367 YOUR DATA IS LOST@#!! Do we have backups of all our data???? - The stuff we cannot afford to lose?? How

More information

RAID Technology Overview

RAID Technology Overview RAID Technology Overview HP Smart Array RAID Controllers HP Part Number: J6369-90050 Published: September 2007 Edition: 1 Copyright 2007 Hewlett-Packard Development Company L.P. Legal Notices Copyright

More information

Guide to SATA Hard Disks Installation and RAID Configuration

Guide to SATA Hard Disks Installation and RAID Configuration Guide to SATA Hard Disks Installation and RAID Configuration 1. Guide to SATA Hard Disks Installation...2 1.1 Serial ATA (SATA) Hard Disks Installation...2 2. Guide to RAID Confi gurations...3 2.1 Introduction

More information

Price/performance Modern Memory Hierarchy

Price/performance Modern Memory Hierarchy Lecture 21: Storage Administration Take QUIZ 15 over P&H 6.1-4, 6.8-9 before 11:59pm today Project: Cache Simulator, Due April 29, 2010 NEW OFFICE HOUR TIME: Tuesday 1-2, McKinley Last Time Exam discussion

More information

Data Storage - II: Efficient Usage & Errors

Data Storage - II: Efficient Usage & Errors Data Storage - II: Efficient Usage & Errors Week 10, Spring 2005 Updated by M. Naci Akkøk, 27.02.2004, 03.03.2005 based upon slides by Pål Halvorsen, 12.3.2002. Contains slides from: Hector Garcia-Molina

More information

SATA II 4 Port PCI RAID Card RC217 User Manual

SATA II 4 Port PCI RAID Card RC217 User Manual SATA II 4 Port PCI RAID Card RC217 SATA II 4 Port PCI RAID Card This Manual is for many Models of SATAII RAID5 HBA that uses Silicon Image SATA II SiI3124 chipset: 1) 32bit PCI bus host card 2) 64bit PCI-X

More information

PIONEER RESEARCH & DEVELOPMENT GROUP

PIONEER RESEARCH & DEVELOPMENT GROUP SURVEY ON RAID Aishwarya Airen 1, Aarsh Pandit 2, Anshul Sogani 3 1,2,3 A.I.T.R, Indore. Abstract RAID stands for Redundant Array of Independent Disk that is a concept which provides an efficient way for

More information

Storage node capacity in RAID0 is equal to the sum total capacity of all disks in the storage node.

Storage node capacity in RAID0 is equal to the sum total capacity of all disks in the storage node. RAID configurations defined 1/7 Storage Configuration: Disk RAID and Disk Management > RAID configurations defined Next RAID configurations defined The RAID configuration you choose depends upon how you

More information

4 Channel 6-Port SATA 6Gb/s PCIe RAID Host Card

4 Channel 6-Port SATA 6Gb/s PCIe RAID Host Card 4 Channel 6-Port SATA 6Gb/s PCIe RAID Host Card User Manual Model: UGT-ST644R All brand names and trademarks are properties of their respective owners www.vantecusa.com Contents: Chapter 1: Introduction...

More information

RAID OPTION ROM USER MANUAL. Version 1.6

RAID OPTION ROM USER MANUAL. Version 1.6 RAID OPTION ROM USER MANUAL Version 1.6 RAID Option ROM User Manual Copyright 2008 Advanced Micro Devices, Inc. All Rights Reserved. Copyright by Advanced Micro Devices, Inc. (AMD). No part of this manual

More information

RAID 0 (striping) RAID 1 (mirroring)

RAID 0 (striping) RAID 1 (mirroring) RAID 0 (striping) RAID 0 uses the read/write capabilities of two or more hard drives working together to maximize storage performance. Data in a RAID 0 volume is arranged into blocks that are spread across

More information

Guide to SATA Hard Disks Installation and RAID Configuration

Guide to SATA Hard Disks Installation and RAID Configuration Guide to SATA Hard Disks Installation and RAID Configuration 1. Guide to SATA Hard Disks Installation... 2 1.1 Serial ATA (SATA) Hard Disks Installation... 2 2. Guide to RAID Configurations... 3 2.1 Introduction

More information

RAID 5 rebuild performance in ProLiant

RAID 5 rebuild performance in ProLiant RAID 5 rebuild performance in ProLiant technology brief Abstract... 2 Overview of the RAID 5 rebuild process... 2 Estimating the mean-time-to-failure (MTTF)... 3 Factors affecting RAID 5 array rebuild

More information

Storage Technologies - 2

Storage Technologies - 2 Antoniu Pop 1 The University of Manchester COMP 25212 Storage Technologies - 2 Antoniu Pop antoniu.pop@manchester.ac.uk 16 April 2015 Antoniu Pop 2 The University of Manchester COMP 25212 Storage Technologies

More information

The PCIe solution from ExaSAN

The PCIe solution from ExaSAN The PCIe solution from ExaSAN An outlook on how PCIe can help with your media and entertainment video environment. Who we are? Since 1995 Accusys Storage Ltd. has created generations of cutting-edge and

More information

1 Storage Devices Summary

1 Storage Devices Summary Chapter 1 Storage Devices Summary Dependability is vital Suitable measures Latency how long to the first bit arrives Bandwidth/throughput how fast does stuff come through after the latency period Obvious

More information

PCIe SATA 6G Raid Card

PCIe SATA 6G Raid Card PCIe SATA 6G Raid Card User Manual Ver. 1.00 All brand names and trademarks are properties of their respective owners. Contents: Chapter 1: Introduction... 3 1.1 Product Introduction... 3 1.2 Features...

More information

CS161: Operating Systems

CS161: Operating Systems CS161: Operating Systems Matt Welsh mdw@eecs.harvard.edu Lecture 18: RAID April 19, 2007 2007 Matt Welsh Harvard University 1 RAID Redundant Arrays of Inexpensive Disks Invented in 1986-1987 by David Patterson

More information

RAID Basics Training Guide

RAID Basics Training Guide RAID Basics Training Guide Discover a Higher Level of Performance RAID matters. Rely on Intel RAID. Table of Contents 1. What is RAID? 2. RAID Levels RAID 0 RAID 1 RAID 5 RAID 6 RAID 10 RAID 0+1 RAID 1E

More information

CS420: Operating Systems

CS420: Operating Systems NK YORK COLLEGE OF PENNSYLVANIA HG OK 2 RAID YORK COLLEGE OF PENNSYLVAN James Moscola Department of Physical Sciences York College of Pennsylvania Based on Operating System Concepts, 9th Edition by Silberschatz,

More information

GENERAL INFORMATION COPYRIGHT... 3 NOTICES... 3 XD5 PRECAUTIONS... 3 INTRODUCTION... 4 FEATURES... 4 SYSTEM REQUIREMENT... 4

GENERAL INFORMATION COPYRIGHT... 3 NOTICES... 3 XD5 PRECAUTIONS... 3 INTRODUCTION... 4 FEATURES... 4 SYSTEM REQUIREMENT... 4 1 Table of Contents GENERAL INFORMATION COPYRIGHT... 3 NOTICES... 3 XD5 PRECAUTIONS... 3 INTRODUCTION... 4 FEATURES... 4 SYSTEM REQUIREMENT... 4 XD5 FAMILULARIZATION... 5 PACKAGE CONTENTS... 5 HARDWARE

More information

Redundant Array of Independent Disks (RAID)

Redundant Array of Independent Disks (RAID) For Data Centers Redundant Array of Independent Disks (RAID) Combine and control multiple storage devices for better performance and reliability Application note 2014 Samsung Electronics Co. 1. What is?

More information

RAID technology and IBM TotalStorage NAS products

RAID technology and IBM TotalStorage NAS products IBM TotalStorage Network Attached Storage October 2001 RAID technology and IBM TotalStorage NAS products By Janet Anglin and Chris Durham Storage Networking Architecture, SSG Page No.1 Contents 2 RAID

More information

Best Practices RAID Implementations for Snap Servers and JBOD Expansion

Best Practices RAID Implementations for Snap Servers and JBOD Expansion STORAGE SOLUTIONS WHITE PAPER Best Practices RAID Implementations for Snap Servers and JBOD Expansion Contents Introduction...1 Planning for the End Result...1 Availability Considerations...1 Drive Reliability...2

More information

An Introduction to RAID. Giovanni Stracquadanio stracquadanio@dmi.unict.it www.dmi.unict.it/~stracquadanio

An Introduction to RAID. Giovanni Stracquadanio stracquadanio@dmi.unict.it www.dmi.unict.it/~stracquadanio An Introduction to RAID Giovanni Stracquadanio stracquadanio@dmi.unict.it www.dmi.unict.it/~stracquadanio Outline A definition of RAID An ensemble of RAIDs JBOD RAID 0...5 Configuring and testing a Linux

More information

TECHNOLOGY BRIEF. Compaq RAID on a Chip Technology EXECUTIVE SUMMARY CONTENTS

TECHNOLOGY BRIEF. Compaq RAID on a Chip Technology EXECUTIVE SUMMARY CONTENTS TECHNOLOGY BRIEF August 1999 Compaq Computer Corporation Prepared by ISSD Technology Communications CONTENTS Executive Summary 1 Introduction 3 Subsystem Technology 3 Processor 3 SCSI Chip4 PCI Bridge

More information

Summer Student Project Report

Summer Student Project Report Summer Student Project Report Dimitris Kalimeris National and Kapodistrian University of Athens June September 2014 Abstract This report will outline two projects that were done as part of a three months

More information

Disk Array Data Organizations and RAID

Disk Array Data Organizations and RAID Guest Lecture for 15-440 Disk Array Data Organizations and RAID October 2010, Greg Ganger 1 Plan for today Why have multiple disks? Storage capacity, performance capacity, reliability Load distribution

More information

Version : 1.0. SR3620-2S-SB2 User Manual. SOHORAID Series

Version : 1.0. SR3620-2S-SB2 User Manual. SOHORAID Series Version : 1.0 SR3620-2S-SB2 User Manual SOHORAID Series Introduction About this Manual Thank you for using the product of RAIDON Technology Inc. This user manual will introduce the STARDOM SR3620-2S-SB2

More information

How to choose the right RAID for your Dedicated Server

How to choose the right RAID for your Dedicated Server Overview of RAID Let's first address, "What is RAID and what does RAID stand for?" RAID, an acronym for "Redundant Array of Independent Disks, is a storage technology that links or combines multiple hard

More information

Algorithms and Methods for Distributed Storage Networks 4: Volume Manager and RAID Christian Schindelhauer

Algorithms and Methods for Distributed Storage Networks 4: Volume Manager and RAID Christian Schindelhauer Algorithms and Methods for Distributed Storage Networks 4: Volume Manager and RAID Institut für Informatik Wintersemester 2007/08 RAID Redundant Array of Independent Disks Patterson, Gibson, Katz, A Case

More information

RAID. Contents. Definition and Use of the Different RAID Levels. The different RAID levels: Definition Cost / Efficiency Reliability Performance

RAID. Contents. Definition and Use of the Different RAID Levels. The different RAID levels: Definition Cost / Efficiency Reliability Performance RAID Definition and Use of the Different RAID Levels Contents The different RAID levels: Definition Cost / Efficiency Reliability Performance Further High Availability Aspects Performance Optimization

More information

The Bus (PCI and PCI-Express)

The Bus (PCI and PCI-Express) 4 Jan, 2008 The Bus (PCI and PCI-Express) The CPU, memory, disks, and all the other devices in a computer have to be able to communicate and exchange data. The technology that connects them is called the

More information

VERY IMPORTANT NOTE! - RAID

VERY IMPORTANT NOTE! - RAID Disk drives are an integral part of any computing system. Disk drives are usually where the operating system and all of an enterprise or individual s data are stored. They are also one of the weakest links

More information

Lenovo RAID Introduction Reference Information

Lenovo RAID Introduction Reference Information Lenovo RAID Introduction Reference Information Using a Redundant Array of Independent Disks (RAID) to store data remains one of the most common and cost-efficient methods to increase server's storage performance,

More information

ECE 5730 Memory Systems. Redundant Array of Inexpensive (Independent) Disks (RAID)

ECE 5730 Memory Systems. Redundant Array of Inexpensive (Independent) Disks (RAID) ECE 5730 Memory Systems Spring 2009 Redundant Array of Inexpensive (Independent) Disks (RAID) Lecture 24: 1 No office hours today Announcements Make-up class #2 Thursday, April 30, 6:00-7:15pm, PH 403

More information

COMP303 Computer Architecture Lecture 17. Storage

COMP303 Computer Architecture Lecture 17. Storage COMP303 Computer Architecture Lecture 17 Storage Review: Major Components of a Computer Processor Devices Control Memory Output Datapath Input Secondary Memory (Disk) Main Memory Cache Magnetic Disk Purpose

More information

Performance Report Modular RAID for PRIMERGY

Performance Report Modular RAID for PRIMERGY Performance Report Modular RAID for PRIMERGY Version 1.1 March 2008 Pages 15 Abstract This technical documentation is designed for persons, who deal with the selection of RAID technologies and RAID controllers

More information

RAID Manual. Edition. Trademarks V1.0 P/N: 91-187-CK8-A5-0E

RAID Manual. Edition. Trademarks V1.0 P/N: 91-187-CK8-A5-0E RAID Manual Edition V1.0 P/N: 91-187-CK8-A5-0E Trademarks All brand or product names mentioned are trademarks or registered trademarks of their respective holders. Contents NVIDIA RAID... 1 RAID Arrays...

More information

Data Storage - II: Efficient Usage & Errors. Contains slides from: Naci Akkök, Hector Garcia-Molina, Pål Halvorsen, Ketil Lund

Data Storage - II: Efficient Usage & Errors. Contains slides from: Naci Akkök, Hector Garcia-Molina, Pål Halvorsen, Ketil Lund Data Storage - II: Efficient Usage & Errors Contains slides from: Naci Akkök, Hector Garcia-Molina, Pål Halvorsen, Ketil Lund Overview Efficient storage usage Disk errors Error recovery INF3 7.3.26 Ellen

More information

Chapter 6 External Memory. Dr. Mohamed H. Al-Meer

Chapter 6 External Memory. Dr. Mohamed H. Al-Meer Chapter 6 External Memory Dr. Mohamed H. Al-Meer 6.1 Magnetic Disks Types of External Memory Magnetic Disks RAID Removable Optical CD ROM CD Recordable CD-R CD Re writable CD-RW DVD Magnetic Tape 2 Introduction

More information

RAID HARDWARE. On board SATA RAID controller. RAID drive caddy (hot swappable) SATA RAID controller card. Anne Watson 1

RAID HARDWARE. On board SATA RAID controller. RAID drive caddy (hot swappable) SATA RAID controller card. Anne Watson 1 RAID HARDWARE On board SATA RAID controller SATA RAID controller card RAID drive caddy (hot swappable) Anne Watson 1 RAID The word redundant means an unnecessary repetition. The word array means a lineup.

More information

Storage management: talk roadmap

Storage management: talk roadmap Storage management: talk roadmap! Why disk arrays? Failures Redundancy! RAID! Performance considerations normal and degraded modes! Disk array designs and implementations! Case study: HP AutoRAID 2000-03-StAndrews-arrays,

More information

CHAPTER 4 RAID. Section Goals. Upon completion of this section you should be able to:

CHAPTER 4 RAID. Section Goals. Upon completion of this section you should be able to: HPTER 4 RI s it was originally proposed, the acronym RI stood for Redundant rray of Inexpensive isks. However, it has since come to be known as Redundant rray of Independent isks. RI was originally described

More information

RAID User Guide. Edition. Trademarks V1.0 P/N: 91-187C51GME0-00

RAID User Guide. Edition. Trademarks V1.0 P/N: 91-187C51GME0-00 RAID User Guide Edition V1.0 P/N: 91-187C51GME0-00 Trademarks All brand or product names mentioned are trademarks or registered trademarks of their respective holders. Contents NVIDIA RAID...1 RAID Arrays...1

More information

RAID Overview: Identifying What RAID Levels Best Meet Customer Needs. Diamond Series RAID Storage Array

RAID Overview: Identifying What RAID Levels Best Meet Customer Needs. Diamond Series RAID Storage Array ATTO Technology, Inc. Corporate Headquarters 155 Crosspoint Parkway Amherst, NY 14068 Phone: 716-691-1999 Fax: 716-691-9353 www.attotech.com sales@attotech.com RAID Overview: Identifying What RAID Levels

More information

RAID Performance Analysis

RAID Performance Analysis RAID Performance Analysis We have six 500 GB disks with 8 ms average seek time. They rotate at 7200 RPM and have a transfer rate of 20 MB/sec. The minimum unit of transfer to each disk is a 512 byte sector.

More information

5-BAY RAID STATION. Manual

5-BAY RAID STATION. Manual 5-BAY RAID STATION Manual Content 1. Features 3 1.1 Overview 3 1.2 SATA features 3 1.3 USB features 4 2. Specifications 4 3. System requirements 4 4. The device at a glance 4 4.1 Rear panel 5 4.2 The LED

More information

Fault Tolerance & Reliability CDA 5140. Chapter 3 RAID & Sample Commercial FT Systems

Fault Tolerance & Reliability CDA 5140. Chapter 3 RAID & Sample Commercial FT Systems Fault Tolerance & Reliability CDA 5140 Chapter 3 RAID & Sample Commercial FT Systems - basic concept in these, as with codes, is redundancy to allow system to continue operation even if some components

More information

Computer Organization II. CMSC 3833 Lecture 61

Computer Organization II. CMSC 3833 Lecture 61 RAID, an acronym for Redundant Array of Independent Disks was invented to address problems of disk reliability, cost, and performance. In RAID, data is stored across many disks, with extra disks added

More information

Storage Devices for Database Systems

Storage Devices for Database Systems Storage Devices for Database Systems These slides are mostly taken verbatim, or with minor changes, from those prepared by Stephen Hegner (http://www.cs.umu.se/ hegner/) of Umeå University Storage Devices

More information

Intel ESB2 SATA RAID Setup Guidelines

Intel ESB2 SATA RAID Setup Guidelines Intel ESB2 SATA RAID Setup Guidelines Intel ESB2 SATA RAID Setup Guidelines After all the hardware has been installed, you must first configure Intel ESB2 SATA RAID Settings before you install the Windows

More information

NVIDIA RAID Installation Guide

NVIDIA RAID Installation Guide NVIDIA RAID Installation Guide 1. NVIDIA BIOS RAID Installation Guide.. 2 1.1 Introduction to RAID. 2 1.2 RAID Configurations Precautions.. 3 1.3 Create Disk Array. 4 2. NVIDIA Windows RAID Installation

More information

Solving Data Loss in Massive Storage Systems Jason Resch Cleversafe

Solving Data Loss in Massive Storage Systems Jason Resch Cleversafe Solving Data Loss in Massive Storage Systems Jason Resch Cleversafe 2010 Storage Developer Conference. Insert Your Company Name. All Rights Reserved. 1 In the beginning There was replication Long before

More information

ESATA PCI CARD. User s Manual

ESATA PCI CARD. User s Manual ESATA PCI CARD User s Manual Introduction... 3 System Requirements... 3 RAID Introduction... 3 BIOS Configuration Utility... 5 Configuring Arrays... 5 RAID Mode Definitions... 5 BIOS Configuration Utility...

More information

Intel Rapid Storage Technology

Intel Rapid Storage Technology Intel Rapid Storage Technology User Guide August 2011 Revision 1.0 1 Document Number: XXXXXX INFORMATION IN THIS DOCUMENT IS PROVIDED IN CONNECTION WITH INTEL PRODUCTS. NO LICENSE, EXPRESS OR IMPLIED,

More information

Disk Storage & Dependability

Disk Storage & Dependability Disk Storage & Dependability Computer Organization Architectures for Embedded Computing Wednesday 19 November 14 Many slides adapted from: Computer Organization and Design, Patterson & Hennessy 4th Edition,

More information

Today: Coda, xfs. Coda Overview

Today: Coda, xfs. Coda Overview Today: Coda, xfs Case Study: Coda File System Brief overview of other file systems xfs Log structured file systems HDFS Object Storage Systems CS677: Distributed OS Lecture 21, page 1 Coda Overview DFS

More information

Chapter 10: Mass-Storage Systems

Chapter 10: Mass-Storage Systems Chapter 10: Mass-Storage Systems Physical structure of secondary storage devices and its effects on the uses of the devices Performance characteristics of mass-storage devices Disk scheduling algorithms

More information

Improving Lustre OST Performance with ClusterStor GridRAID. John Fragalla Principal Architect High Performance Computing

Improving Lustre OST Performance with ClusterStor GridRAID. John Fragalla Principal Architect High Performance Computing Improving Lustre OST Performance with ClusterStor GridRAID John Fragalla Principal Architect High Performance Computing Legacy RAID 6 No Longer Sufficient 2013 RAID 6 data protection challenges Long rebuild

More information

4-PORT SATA III PCI EXPRESS CARD. User Manual DS

4-PORT SATA III PCI EXPRESS CARD. User Manual DS 4-PORT SATA III PCI EXPRESS CARD User Manual DS-30104-1 Chapter 1: Introduction 1.1 Product Introduction This board is a single-chip, PCI Express to four SATA Gen III 6Gb/s channels host controller that

More information

200 Chapter 7. (This observation is reinforced and elaborated in Exercises 7.5 and 7.6, and the reader is urged to work through them.

200 Chapter 7. (This observation is reinforced and elaborated in Exercises 7.5 and 7.6, and the reader is urged to work through them. 200 Chapter 7 (This observation is reinforced and elaborated in Exercises 7.5 and 7.6, and the reader is urged to work through them.) 7.2 RAID Disks are potential bottlenecks for system performance and

More information

3PAR Fast RAID: High Performance Without Compromise

3PAR Fast RAID: High Performance Without Compromise 3PAR Fast RAID: High Performance Without Compromise Karl L. Swartz Document Abstract: 3PAR Fast RAID allows the 3PAR InServ Storage Server to deliver higher performance with less hardware, reducing storage

More information

Getting Started With RAID

Getting Started With RAID Dell Systems Getting Started With RAID www.dell.com support.dell.com Notes, Notices, and Cautions NOTE: A NOTE indicates important information that helps you make better use of your computer. NOTICE: A

More information

Disks and RAID. Profs. Bracy and Van Renesse. based on slides by Prof. Sirer

Disks and RAID. Profs. Bracy and Van Renesse. based on slides by Prof. Sirer Disks and RAID Profs. Bracy and Van Renesse based on slides by Prof. Sirer 50 Years Old! 13th September 1956 The IBM RAMAC 350 Stored less than 5 MByte Reading from a Disk Must specify: cylinder # (distance

More information

Q & A From Hitachi Data Systems WebTech Presentation:

Q & A From Hitachi Data Systems WebTech Presentation: Q & A From Hitachi Data Systems WebTech Presentation: RAID Concepts 1. Is the chunk size the same for all Hitachi Data Systems storage systems, i.e., Adaptable Modular Systems, Network Storage Controller,

More information

RAID Made Easy By Jon L. Jacobi, PCWorld

RAID Made Easy By Jon L. Jacobi, PCWorld 9916 Brooklet Drive Houston, Texas 77099 Phone 832-327-0316 www.safinatechnolgies.com RAID Made Easy By Jon L. Jacobi, PCWorld What is RAID, why do you need it, and what are all those mode numbers that

More information

RAID Technology. RAID Overview

RAID Technology. RAID Overview Technology In the 1980s, hard-disk drive capacities were limited and large drives commanded a premium price. As an alternative to costly, high-capacity individual drives, storage system developers began

More information

Outline. Database Management and Tuning. Overview. Hardware Tuning. Johann Gamper. Unit 12

Outline. Database Management and Tuning. Overview. Hardware Tuning. Johann Gamper. Unit 12 Outline Database Management and Tuning Hardware Tuning Johann Gamper 1 Free University of Bozen-Bolzano Faculty of Computer Science IDSE Unit 12 2 3 Conclusion Acknowledgements: The slides are provided

More information

RAID. Storage-centric computing, cloud computing. Benefits:

RAID. Storage-centric computing, cloud computing. Benefits: RAID Storage-centric computing, cloud computing. Benefits: Improved reliability (via error correcting code, redundancy). Improved performance (via redundancy). Independent disks. RAID Level 0 Provides

More information

RAID 6 with HP Advanced Data Guarding technology:

RAID 6 with HP Advanced Data Guarding technology: RAID 6 with HP Advanced Data Guarding technology: a cost-effective, fault-tolerant solution technology brief Abstract... 2 Introduction... 2 Functions and limitations of RAID schemes... 3 Fault tolerance

More information

What is RAID? data reliability with performance

What is RAID? data reliability with performance What is RAID? RAID is the use of multiple disks and data distribution techniques to get better Resilience and/or Performance RAID stands for: Redundant Array of Inexpensive / Independent Disks RAID can

More information

HP dx5150 RAID Installation and Setup Guide Version 1.10. Document Part Number: 403571-001

HP dx5150 RAID Installation and Setup Guide Version 1.10. Document Part Number: 403571-001 HP dx5150 RAID Installation and Setup Guide Version 1.10 Document Part Number: 403571-001 July 2005 Copyright 2005 Hewlett-Packard Development Company, L.P. The information contained herein is subject

More information