Storage and File Structure. DBMS and Storage/File Structure. Storage Hierarchy

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Storage and File Structure. DBMS and Storage/File Structure. Storage Hierarchy"

Transcription

1 Storage and File Structure DBMS and Storage/File Structure Why do we need to know about storage/file structure Many database technologies are developed to utilize the storage architecture/hierarchy Data in the database needs to be organized and stored/retrieved efficiently Storage Hierarchy Volatile primary storage Cache Memory unit price Non-volatile Secondary storage Tertiary storage Flash Memory Magnetic Disk Optical Disk Magnetic Tape speed 1

2 Primary Storage (Volatile) Cache Speed: 7 to 20 ns (1 nanosecond = 10 9 seconds) Capacity: A typical PC level 2 cache 64KB-2 MB. Within processors, level 1 cache usually ranges in size from 8 KB to 64 KB. Main memory: Speed: 10s to 100s of nanoseconds; Capacity: Up to a few Gigabytes widely used currently per-byte costs have decreased roughly factor of 2 every 2 to 3 years) Secondary Storage (Non-volatile) Flash memory Speed: read speed similar to main memory, write is much slower Capacity: 32M to 512M currently Forms: SmartMedia, memory stick, secure digital, BIOS Cost: roughly same as main memory Magnetic-disk Capacities: up to roughly 100 GB currently Growing constantly and rapidly with technology improvements (factor of 2 to 3 every 2 years) Tertiary Storage (Non-volatile) Optical storage CD-ROM (640 MB) and DVD (4.7 to 17 GB) most popular forms CD-R, DVD-R, CD-RW, DVD-RW, and DVD-RAM Reads and writes are slower than with magnetic disk Juke-box systems, with large numbers of removable disks, a few drives, and a mechanism for automatic loading/unloading of disks available for storing large volumes of data 2

3 Tertiary Storage (Non-volatile) Tape storage non-volatile, used primarily for backup (to recover from disk failure), and for archival data sequential-access much slower than disk very high capacity (40 to 300 GB tapes available) Tape jukeboxes available for storing massive amounts of data hundreds of terabytes (1 terabyte = 10 9 bytes) to even a petabyte (1 petabyte = bytes) Between Memory and Disk The permanent residency of database is mostly on disk In database, cost is usually measured by the number of disk I/O But disks are too slow and we need memory to be the buffers but memory is volatile this introduced a number of issues Lets talk about disk 3

4 Disk Subsystem Disk interface standards families ATA(AT adaptor) range of standards SCSI(Small Computer System Interconnect) range of standards Several variants of each standard (different speeds and capabilities) Disk Speed Rotation time/latency milliseconds Data-transfer rate (4-8MB/sec) Seek time (milliseconds) Access time = seek time + latency Typical numbers: 16,000 tracks per platter sectors per track: bytes per sector 4-16KB per block 5,400-15,000 r p m RAID RAID: Redundant Arrays of Independent Disks high capacity and high speed by using multiple disks in parallel, and high reliability by storing data redundantly 4

5 Mean time to failure (MTTF) Average time the disk is expected to run continuously without any failure. Typically 3 to 5 years (1 year = 8,760 hours) MTTF = 30,000 to 1,200,000 hours for a new disk an MTTF of 1,200,000 hours for a new disk means that given 1000 relatively new disks, on an average one will fail every 1200 hours When number of disks increase, the chance of some disk failure increase proportionally Parallelism Two main goals of parallelism in a disk system: 1. Load balance multiple small accesses to increase throughput 2. Parallelize large accesses to reduce response time. Basic strategy: Stripping Redundancy store extra information that can be used to rebuild information lost in a disk failure Basic strategy: mirroring, parity Data Parity Mean time to data loss depends on mean time to failure, and mean time to repair E.g. MTTF of 100,000 hours, mean time to repair of 10 hours gives mean time to data loss of 500*10 6 hours (or 57,000 years) for a mirrored pair of disks (ignoring dependent failure modes) 5

6 RAID levels Choice of RAID Levels Level 1 provides much better write performance than level 5 Level 5 requires at least 2 block reads and 2 block writes to write a single block, whereas Level 1 only requires 2 block writes Level 1 preferred for high update environments such as log disks Level 1 had higher storage cost than level 5 disk drive capacities increasing rapidly (50%/year) whereas disk access times have decreased much less (x 3 in 10 years) I/O requirements have increased greatly, e.g. for Web servers When enough disks have been bought to satisfy required rate of I/O, they often have spare storage capacity so there is often no extra monetary cost for Level 1! Level 5 is preferred for applications with low update rate, and large amounts of data Level 1 is preferred for all other applications Buffer Management Database can not fit entirely in memory, needs memory as a buffer for speed reasons LRU is used in many OS Spatial and temporal locality due to loops Database has a more predictable behavior Example: join 6

7 DBMS Buffer Management Strategies Pinned block memory block that is not allowed to be written back to disk. Toss-immediate strategy frees the space occupied by a block as soon as the final tuple of that block has been processed Most recently used (MRU) strategy system must pin the block currently being processed. After the final tuple of that block has been processed, the block is unpinned, and it becomes the most recently used block. Statistical information based E.g., the data dictionary is frequently accessed. Heuristic: keep data-dictionary blocks in main memory buffer Buffer managers also support forced output of blocks for the purpose of recovery Exercises 7

Chapter 11: Storage and File Structure. Classification of Physical Storage Media

Chapter 11: Storage and File Structure. Classification of Physical Storage Media Chapter 11: Storage and File Structure! Overview of Physical Storage Media! Magnetic Disks! RAID! Tertiary Storage! Storage Access! File Organization! Organization of Records in Files! Data-Dictionary

More information

Chapter 11: Storage and File Structure

Chapter 11: Storage and File Structure Chapter 11: Storage and File Structure! Overview of Physical Storage Media! Magnetic Disks! RAID! Tertiary Storage! Storage Access! File Organization! Organization of Records in Files! Data-Dictionary

More information

Classification of Physical Storage Media. Chapter 11: Storage and File Structure. Physical Storage Media (Cont.) Physical Storage Media

Classification of Physical Storage Media. Chapter 11: Storage and File Structure. Physical Storage Media (Cont.) Physical Storage Media Chapter 11: Storage and File Structure Classification of Physical Storage Media! Overview of Physical Storage Media! Magnetic Disks! RAID! Tertiary Storage! Storage Access! File Organization! Organization

More information

6. Storage and File Structures

6. Storage and File Structures ECS-165A WQ 11 110 6. Storage and File Structures Goals Understand the basic concepts underlying different storage media, buffer management, files structures, and organization of records in files. Contents

More information

Storage and File Structure

Storage and File Structure Storage and File Structure Chapter 10: Storage and File Structure Overview of Physical Storage Media Magnetic Disks RAID Tertiary Storage Storage Access File Organization Organization of Records in Files

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

Chapter 11: Storage and File Structure

Chapter 11: Storage and File Structure Chapter 11: Storage and File Structure Rev. Aug 1, 2006 Database System Concepts, 5th Ed. See www.db-book.com for conditions on re-use Chapter 11: Storage and File Structure Overview of Physical Storage

More information

Chapter 10: Storage and File Structure

Chapter 10: Storage and File Structure Chapter 10: Storage and File Structure Overview of Physical Storage Media Magnetic Disks RAID Tertiary Storage Storage Access File Organization Organization of Records in Files Data-Dictionary Storage

More information

Chapter 8. Secondary Storage. McGraw-Hill/Irwin. Copyright 2008 by The McGraw-Hill Companies, Inc. All rights reserved.

Chapter 8. Secondary Storage. McGraw-Hill/Irwin. Copyright 2008 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 8 Secondary Storage McGraw-Hill/Irwin Copyright 2008 by The McGraw-Hill Companies, Inc. All rights reserved. Competencies (Page 1 of 2) Distinguish between primary and secondary storage Describe

More information

Computer Organization

Computer Organization Chapter 5 Computer Organization OBJECTIVES Distinguish between the three components of a computer hardware. List the functionality of each component. Understand memory addressing and calculate the number

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

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

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

Introduction Disks RAID Tertiary storage. Mass Storage. CMSC 412, University of Maryland. Guest lecturer: David Hovemeyer.

Introduction Disks RAID Tertiary storage. Mass Storage. CMSC 412, University of Maryland. Guest lecturer: David Hovemeyer. Guest lecturer: David Hovemeyer November 15, 2004 The memory hierarchy Red = Level Access time Capacity Features Registers nanoseconds 100s of bytes fixed Cache nanoseconds 1-2 MB fixed RAM nanoseconds

More information

Carnegie Mellon Univ. Dept. of Computer Science Database Applications. Overview. Faloutsos CMU SCS

Carnegie Mellon Univ. Dept. of Computer Science Database Applications. Overview. Faloutsos CMU SCS Faloutsos 15-415 Carnegie Mellon Univ. Dept. of Computer Science 15-415 - Database Applications Lecture #8 (R&G ch9) Storing Data: Disks and Files Faloutsos 15-415 #1 Overview Memory hierarchy RAID (briefly)

More information

CSCA0201 FUNDAMENTALS OF COMPUTING. Chapter 5 Storage Devices

CSCA0201 FUNDAMENTALS OF COMPUTING. Chapter 5 Storage Devices CSCA0201 FUNDAMENTALS OF COMPUTING Chapter 5 Storage Devices 1 1. Computer Data Storage 2. Types of Storage 3. Storage Device Features 4. Other Examples of Storage Device 2 Storage Devices A storage device

More information

Storing Data: Disks and Files

Storing Data: Disks and Files Storing : Disks and Files Chapter 7 base Management Systems, R. Ramakrishnan and J. Gehrke 1 Disks and Files DBMS stores information on ( hard ) disks. This has major implications for DBMS implementation!

More information

Backing storage and Memory Year 9 - ICT Notes

Backing storage and Memory Year 9 - ICT Notes Backing storage and Memory Year 9 - ICT Notes Storage and Memory Storage Also called as backing storage/secondary storage Examples of storage media are Hard disks Optical disks( CD, DVD, Blu-ray) Flash

More information

Storing Data: Disks and Files

Storing Data: Disks and Files Storing Data: Disks and Files [R&G] Chapter 9 CS 4320 1 Data on External Storage Disks: Can retrieve random page at fixed cost But reading several consecutive pages is much cheaper than reading them in

More information

Storing Data: Disks and Files

Storing Data: Disks and Files Storing Data: Disks and Files Chapter 7 Yea, from the table of my memory I ll wipe away all trivial fond records. -- Shakespeare, Hamlet Database Management Systems, R. Ramakrishnan and J. Gehrke 1 Disks

More information

Learning Objectives. Explain the difference between storage systems and memory. Name several general properties of storage systems.

Learning Objectives. Explain the difference between storage systems and memory. Name several general properties of storage systems. Chapter 4 Storage Learning Objectives Explain the difference between storage systems and memory. Name several general properties of storage systems. Identify the two primary types of magnetic disk systems

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

Physical Data Organization

Physical Data Organization Physical Data Organization Database design using logical model of the database - appropriate level for users to focus on - user independence from implementation details Performance - other major factor

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

Computer Peripherals

Computer Peripherals Computer Peripherals Reading: Chapter 10 (except 10.6) Peripherals Devices that are separate from the basic computer Not the CPU, memory, or power supply Classified as input, output, and storage Connect

More information

William Stallings Computer Organization and Architecture 7 th Edition. Chapter 6 External Memory

William Stallings Computer Organization and Architecture 7 th Edition. Chapter 6 External Memory William Stallings Computer Organization and Architecture 7 th Edition Chapter 6 External Memory Types of External Memory Magnetic Disk RAID Removable Optical CD-ROM CD-Recordable (CD-R) CD-R/W DVD Magnetic

More information

Physical Storage Media

Physical Storage Media Physical Storage Media These slides are a modified version of the slides of the book Database System Concepts, 5th Ed., McGraw-Hill, by Silberschatz, Korth and Sudarshan. Original slides are available

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

Storing Data: Disks and Files

Storing Data: Disks and Files Storing Data: Disks and Files (From Chapter 9 of textbook) Storing and Retrieving Data Database Management Systems need to: Store large volumes of data Store data reliably (so that data is not lost!) Retrieve

More information

Storing Data: Disks and Files

Storing Data: Disks and Files Storing Data: Disks and Files Chapter 9 Comp 521 Files and Databases Fall 2010 1 Disks and Files DBMS stores information on ( hard ) disks. This has major implications for DBMS design! READ: transfer data

More information

Storage Hierarchy. 10: Storage and File System Basics. Example. Secondary Storage. Tertiary Storage Devices. Typical PC

Storage Hierarchy. 10: Storage and File System Basics. Example. Secondary Storage. Tertiary Storage Devices. Typical PC Storage Hierarchy 10: Storage and File System Basics Last Modified: 6/15/2004 12:10:04 PM Faster, Smaller, More Expensive Registers L1 Cache L2 Cache DRAM Volatile DISK Non-Volatile TAPE Each level acts

More information

Storing Data: Disks and Files. Disks and Files. Why Not Store Everything in Main Memory? Chapter 7

Storing Data: Disks and Files. Disks and Files. Why Not Store Everything in Main Memory? Chapter 7 Storing : Disks and Files Chapter 7 Yea, from the table of my memory I ll wipe away all trivial fond records. -- Shakespeare, Hamlet base Management Systems 3ed, R. Ramakrishnan and J. Gehrke 1 Disks and

More information

administrivia using slides from here on out posted in advance as pdf on website exam back overall happy with results with some exceptions

administrivia using slides from here on out posted in advance as pdf on website exam back overall happy with results with some exceptions administrivia using slides from here on out posted in advance as pdf on website exam back overall happy with results with some exceptions short slides today gets to a good overview point probably a short

More information

High Performance Computer Architecture Prof. Ajit Pal Department of Computer Science and Engineering Indian Institute of Technology, Kharagpur

High Performance Computer Architecture Prof. Ajit Pal Department of Computer Science and Engineering Indian Institute of Technology, Kharagpur High Performance Computer Architecture Prof. Ajit Pal Department of Computer Science and Engineering Indian Institute of Technology, Kharagpur Lecture - 32 Storage Technology Hello and welcome to today

More information

Tech Application Chapter 3 STUDY GUIDE

Tech Application Chapter 3 STUDY GUIDE Name: Class: Date: Tech Application Chapter 3 STUDY GUIDE Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. This type of device retains data

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

Storage Devices. Backing storage is usually non-volatile, so it is generally used to store data for a long time.

Storage Devices. Backing storage is usually non-volatile, so it is generally used to store data for a long time. STORAGE DEVICES Main Memory Main memory (sometimes known as internal memory or primary memory) is another name for RAM (and ROM). The function of Main memory is to hold data and programs which are currently

More information

CS 464/564 Introduction to Database Management System Instructor: Abdullah Mueen

CS 464/564 Introduction to Database Management System Instructor: Abdullah Mueen CS 464/564 Introduction to Database Management System Instructor: Abdullah Mueen LECTURE 14: DATA STORAGE AND REPRESENTATION Data Storage Memory Hierarchy Disks Fields, Records, Blocks Variable-length

More information

Computer Storage. Computer Technology. (S1 Obj 2-3 and S3 Obj 1-1)

Computer Storage. Computer Technology. (S1 Obj 2-3 and S3 Obj 1-1) Computer Storage Computer Technology (S1 Obj 2-3 and S3 Obj 1-1) Storage The place in the computer where data is held while it is not needed for processing A storage device is device used to record (store)

More information

William Stallings Computer Organization and Architecture 8 th Edition. External Memory

William Stallings Computer Organization and Architecture 8 th Edition. External Memory William Stallings Computer Organization and Architecture 8 th Edition Chapter 6 External Memory Types of External Memory Magnetic Disk RAID Removable Optical CD-ROM CD-Recordable (CD-R) CD-R/W DVD Magnetic

More information

Storing Data: Disks and Files

Storing Data: Disks and Files Storing Data: Disks and Files Chapter 7 Instructor: Vladimir Zadorozhny vladimir@sis.pitt.edu Information Science Program School of Information Sciences, University of Pittsburgh 1 Disks and Files DBMS

More information

Chapter 08: The Memory System. Lesson 19: Secondary storage RAID

Chapter 08: The Memory System. Lesson 19: Secondary storage RAID Chapter 08: The Memory System Lesson 19: Secondary storage RAID 1 Objective Understand how a RAID (redundant array of independent disks) used for the databases on multiple disks Seven levels of RAID memory

More information

Outline. Principles of Database Management Systems. Memory Hierarchy: Capacities and access times. CPU vs. Disk Speed ... ...

Outline. Principles of Database Management Systems. Memory Hierarchy: Capacities and access times. CPU vs. Disk Speed ... ... Outline Principles of Database Management Systems Pekka Kilpeläinen (after Stanford CS245 slide originals by Hector Garcia-Molina, Jeff Ullman and Jennifer Widom) Hardware: Disks Access Times Example -

More information

Writing Assignment #2 due Today (5:00pm) - Post on your CSC101 webpage - Ask if you have questions! Lab #2 Today. Quiz #1 Tomorrow (Lectures 1-7)

Writing Assignment #2 due Today (5:00pm) - Post on your CSC101 webpage - Ask if you have questions! Lab #2 Today. Quiz #1 Tomorrow (Lectures 1-7) Overview of Computer Science CSC 101 Summer 2011 Main Memory vs. Auxiliary Storage Lecture 7 July 14, 2011 Announcements Writing Assignment #2 due Today (5:00pm) - Post on your CSC101 webpage - Ask if

More information

Secondary Storage. Any modern computer system will incorporate (at least) two levels of storage: magnetic disk/optical devices/tape systems

Secondary Storage. Any modern computer system will incorporate (at least) two levels of storage: magnetic disk/optical devices/tape systems 1 Any modern computer system will incorporate (at least) two levels of storage: primary storage: typical capacity cost per MB $3. typical access time burst transfer rate?? secondary storage: typical capacity

More information

Secondary Storage Devices 4

Secondary Storage Devices 4 4 Secondary Storage Devices Copyright 2004, Binnur Kurt Content Secondary storage devices Organization of disks Organizing tracks by sector Organizing tracks by blocks Non-data overhead The cost of a disk

More information

Mass-Storage Devices: Disks. CSCI 5103 Operating Systems. Basic Disk Functionality. Magnetic Disks

Mass-Storage Devices: Disks. CSCI 5103 Operating Systems. Basic Disk Functionality. Magnetic Disks Mass-Storage Devices: Disks CSCI 5103 Operating Systems Instructor: Abhishek Chandra Disk Structure and Attachment Disk Scheduling Disk Management RAID Structure Stable Storage 2 Magnetic Disks Most common

More information

Discovering Computers 2008. Chapter 7 Storage

Discovering Computers 2008. Chapter 7 Storage Discovering Computers 2008 Chapter 7 Storage Chapter 7 Objectives Differentiate between storage devices and storage media Describe the characteristics of magnetic disks Describe the characteristics of

More information

Storage. Block Diagram of the Computer System showing the Main & Backing Storage

Storage. Block Diagram of the Computer System showing the Main & Backing Storage Introduction Storage All computer systems need to store data. This is done: Temporarily while a program is running. This is stored in main memory. Long-term to preserve programs and data while not in use.

More information

Chapter 1 Computer System Overview

Chapter 1 Computer System Overview Operating Systems: Internals and Design Principles Chapter 1 Computer System Overview Eighth Edition By William Stallings Operating System Exploits the hardware resources of one or more processors Provides

More information

System Architecture. CS143: Disks and Files. Magnetic disk vs SSD. Structure of a Platter CPU. Disk Controller...

System Architecture. CS143: Disks and Files. Magnetic disk vs SSD. Structure of a Platter CPU. Disk Controller... System Architecture CS143: Disks and Files CPU Word (1B 64B) ~ 10 GB/sec Main Memory System Bus Disk Controller... Block (512B 50KB) ~ 100 MB/sec Disk 1 2 Magnetic disk vs SSD Magnetic Disk Stores data

More information

Chapter 2: Computer-System Structures. Computer System Operation Storage Structure Storage Hierarchy Hardware Protection General System Architecture

Chapter 2: Computer-System Structures. Computer System Operation Storage Structure Storage Hierarchy Hardware Protection General System Architecture Chapter 2: Computer-System Structures Computer System Operation Storage Structure Storage Hierarchy Hardware Protection General System Architecture Operating System Concepts 2.1 Computer-System Architecture

More information

Chapter 9: Peripheral Devices: Magnetic Disks

Chapter 9: Peripheral Devices: Magnetic Disks Chapter 9: Peripheral Devices: Magnetic Disks Basic Disk Operation Performance Parameters and History of Improvement Example disks RAID (Redundant Arrays of Inexpensive Disks) Improving Reliability Improving

More information

Chapter 2 Data Storage

Chapter 2 Data Storage Chapter 2 22 CHAPTER 2. DATA STORAGE 2.1. THE MEMORY HIERARCHY 23 26 CHAPTER 2. DATA STORAGE main memory, yet is essentially random-access, with relatively small differences Figure 2.4: A typical

More information

Storage Options for Document Management

Storage Options for Document Management Storage Options for Document Management Document management and imaging systems store large volumes of data, which must be maintained for long periods of time. Choosing storage is not simply a matter of

More information

Review. Storing Data: Disks and Files. Disks, Memory, and Files. Disks and Files. Costs too much. For ~$1000, PCConnection will sell you either

Review. Storing Data: Disks and Files. Disks, Memory, and Files. Disks and Files. Costs too much. For ~$1000, PCConnection will sell you either Review Storing : Disks and Files Lecture 3 (R&G Chapter 9) Aren t bases Great? Relational model SQL Yea, from the table of my memory I ll wipe away all trivial fond records. -- Shakespeare, Hamlet Disks,

More information

Operating Systems. Redundant Array of Inexpensive Disks (RAID) Thomas Ropars.

Operating Systems. Redundant Array of Inexpensive Disks (RAID) Thomas Ropars. 1 Operating Systems Redundant Array of Inexpensive Disks (RAID) Thomas Ropars thomas.ropars@imag.fr 2016 2 References The content of these lectures is inspired by: Operating Systems: Three Easy Pieces

More information

Mass Storage Structure

Mass Storage Structure Mass Storage Structure 12 CHAPTER Practice Exercises 12.1 The accelerating seek described in Exercise 12.3 is typical of hard-disk drives. By contrast, floppy disks (and many hard disks manufactured before

More information

SIT153 Introduction to Computation

SIT153 Introduction to Computation SIT153 Introduction to Computation Lecture 4-1 Computer Organisation I chapter 5 6 April 2016 Admin matters (1) for the next 2 weeks Study units: (4) Computer organisation (5) Networks Week Date Day Activity

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

Examine Your Strategy, Weigh Your Options in Choosing Removable Storage. Dave Holmstrom Associate Director of New Products Verbatim Corporation

Examine Your Strategy, Weigh Your Options in Choosing Removable Storage. Dave Holmstrom Associate Director of New Products Verbatim Corporation Examine Your Strategy, Weigh Your Options in Choosing Removable Storage Dave Holmstrom Associate Director of New Products Verbatim Corporation Evaluating Storage Solutions What type of data is being stored?

More information

Topics. Hamming Algorithm

Topics. Hamming Algorithm Topics Hamming algorithm Magnetic disks RAID Hamming Algorithm In a Hamming code r parity bits added to m-bit word Forms codeword with length (m + r) bits Bit numbering Starts at with leftmost (high-order)

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

Systems Infrastructure for Data Science. Web Science Group Uni Freiburg WS 2014/15

Systems Infrastructure for Data Science. Web Science Group Uni Freiburg WS 2014/15 Systems Infrastructure for Data Science Web Science Group Uni Freiburg WS 2014/15 Lecture I: Storage Storage Part I of this course Uni Freiburg, WS 2014/15 Systems Infrastructure for Data Science 3 The

More information

McGraw-Hill Technology Education McGraw-Hill Technology Education

McGraw-Hill Technology Education McGraw-Hill Technology Education McGraw-Hill Technology Education McGraw-Hill Technology Education Copyright 2006 by The McGraw-Hill Companies, Inc. All rights reserved. Copyright 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

More information

Chapter 8 Memory Units

Chapter 8 Memory Units Chapter 8 Memory Units Contents: I. Introduction Basic units of Measurement II. RAM,ROM,PROM,EPROM Storage versus Memory III. Auxiliary Storage Devices-Magnetic Tape, Hard Disk, Floppy Disk IV.Optical

More information

Memory Versus Storage How does volatility compare?

Memory Versus Storage How does volatility compare? Chapter 7 p. 7.2 Differentiate between and memory Identify various types of media and devices Explain how a floppy disk stores data Identify the advantages of using high-capacity disks Describe how a hard

More information

Outline. CS 245: Database System Principles. Notes 02: Hardware. Hardware DBMS ... ... Data Storage

Outline. CS 245: Database System Principles. Notes 02: Hardware. Hardware DBMS ... ... Data Storage CS 245: Database System Principles Notes 02: Hardware Hector Garcia-Molina Outline Hardware: Disks Access Times Solid State Drives Optimizations Other Topics: Storage costs Using secondary storage Disk

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

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

Storage. The text highlighted in green in these slides contain external hyperlinks. 1 / 14

Storage. The text highlighted in green in these slides contain external hyperlinks. 1 / 14 Storage Compared to the performance parameters of the other components we have been studying, storage systems are much slower devices. Typical access times to rotating disk storage devices are in the millisecond

More information

Operating System Concepts. Operating System 資 訊 工 程 學 系 袁 賢 銘 老 師

Operating System Concepts. Operating System 資 訊 工 程 學 系 袁 賢 銘 老 師 Lecture 6: Secondary Storage Systems Moving-head Disk Mechanism 6.2 Overview of Mass-Storage Structure Magnetic disks provide bulk of secondary storage of modern computers Drives rotate at 60 to 200 times

More information

Chapter 5 Objectives. Differentiate between storage devices and storage media

Chapter 5 Objectives. Differentiate between storage devices and storage media LECTURE 5: STORAGE Chapter 5 Objectives Differentiate between storage devices and storage media Describe the characteristics of magnetic disks Describe the characteristics of a hard disk Differentiate

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

TH3. Data storage. http://www.bbc.co.uk/schools/gcsebitesize/ict/

TH3. Data storage. http://www.bbc.co.uk/schools/gcsebitesize/ict/ TH3. Data storage http://www.bbc.co.uk/schools/gcsebitesize/ict/ A computer uses two types of storage. A main store consisting of ROM and RAM, and backing stores which can be internal, eg hard disk, or

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

Case for storage. Outline. Magnetic disks. CS2410: Computer Architecture. Storage systems. Sangyeun Cho

Case for storage. Outline. Magnetic disks. CS2410: Computer Architecture. Storage systems. Sangyeun Cho Case for storage CS24: Computer Architecture Storage systems Sangyeun Cho Computer Science Department Shift in focus from computation to communication & storage of information Eg, Cray Research/Thinking

More information

Unit Objectives. Input / Output Ports. Component 4: Introduction to Information and Computer Science. Unit 3: Computer Hardware & Architecture

Unit Objectives. Input / Output Ports. Component 4: Introduction to Information and Computer Science. Unit 3: Computer Hardware & Architecture Component 4: Introduction to Information and Computer Science Unit 3: Computer Hardware & Architecture Lecture 2 This material was developed by Oregon Health & Science University, funded by the Department

More information

Redundant Optical Storage System Using DVD-RAM Library

Redundant Optical Storage System Using DVD-RAM Library Redundant Optical Storage System Using DVD-RAM Library Takaya Tanabe, Makoto Takayanagi, Hidetoshi Tatemiti, Tetsuya Ura, and Manabu Yamamoto tanabe@ilab.ntt.co.jp NTT Integrated Information & Energy Systems

More information

Introduction To Computers: Hardware and Software

Introduction To Computers: Hardware and Software What Is Hardware? Introduction To Computers: Hardware and Software A computer is made up of hardware. Hardware is the physical components of a computer system e.g., a monitor, keyboard, mouse and the computer

More information

Sistemas Operativos: Input/Output Disks

Sistemas Operativos: Input/Output Disks Sistemas Operativos: Input/Output Disks Pedro F. Souto (pfs@fe.up.pt) April 28, 2012 Topics Magnetic Disks RAID Solid State Disks Topics Magnetic Disks RAID Solid State Disks Magnetic Disk Construction

More information

Redundant Array of Independent Disks (RAID) Technology Overview

Redundant Array of Independent Disks (RAID) Technology Overview Redundant Array of Independent Disks (RAID) Technology Overview What is RAID? The basic idea behind RAID is to combine multiple small, inexpensive disk drives into an array to accomplish performance or

More information

High Performance Computing. Course Notes 2007-2008. High Performance Storage

High Performance Computing. Course Notes 2007-2008. High Performance Storage High Performance Computing Course Notes 2007-2008 2008 High Performance Storage Storage devices Primary storage: register (1 CPU cycle, a few ns) Cache (10-200 cycles, 0.02-0.5us) Main memory Local main

More information

Secondary Storage The McGraw-Hill Companies, Inc. All rights reserved.

Secondary Storage The McGraw-Hill Companies, Inc. All rights reserved. Distinguish between primary and secondary storage. Discuss the important characteristics of secondary storage, including media, capacity, storage devices, and access speed. Describe hard disk platters,

More information

KEMENTERIAN PELAJARAN MALAYSIA COMPUTER PARTS & COMPONENTS INPUT DEVICES OUTPUT DEVICES STORAGE DEVICES PUSAT PERKEMBANGAN KURIKULUM

KEMENTERIAN PELAJARAN MALAYSIA COMPUTER PARTS & COMPONENTS INPUT DEVICES OUTPUT DEVICES STORAGE DEVICES PUSAT PERKEMBANGAN KURIKULUM KEMENTERIAN PELAJARAN MALAYSIA Self Access Learning Module ICT Literacy for Secondary School Programme Computer Hardware COMPUTER PARTS & COMPONENTS INPUT DEVICES OUTPUT DEVICES STORAGE DEVICES PUSAT PERKEMBANGAN

More information

COMPUTER HARDWARE. Input- Output and Communication Memory Systems

COMPUTER HARDWARE. Input- Output and Communication Memory Systems COMPUTER HARDWARE Input- Output and Communication Memory Systems Computer I/O I/O devices commonly found in Computer systems Keyboards Displays Printers Magnetic Drives Compact disk read only memory (CD-ROM)

More information

lesson 9 Types of Storage Devices

lesson 9 Types of Storage Devices lesson 9 Types of Storage Devices This lesson includes the following sections: Categorizing Storage Devices Magnetic Storage Devices Optical Storage Devices Categorizing Storage Devices Storage devices

More information

CPS104 Computer Organization and Programming Lecture 18: Input-Output. Robert Wagner

CPS104 Computer Organization and Programming Lecture 18: Input-Output. Robert Wagner CPS104 Computer Organization and Programming Lecture 18: Input-Output Robert Wagner cps 104 I/O.1 RW Fall 2000 Outline of Today s Lecture The I/O system Magnetic Disk Tape Buses DMA cps 104 I/O.2 RW Fall

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

Data Storage and Backup. Sanjay Goel School of Business University at Albany, SUNY

Data Storage and Backup. Sanjay Goel School of Business University at Albany, SUNY Data Storage and Backup Sanjay Goel School of Business University at Albany, SUNY Data Backup 2 Data Backup Why? Files can be accidentally deleted Mission-critical data can become corrupt. Natural disasters

More information

What is an Operating System?

What is an Operating System? Introduction What Operating Systems Do Computer-System Organization Computer-System Architecture Operating-System Structure Operating-System Operations Process Management Memory Management Storage Management

More information

Big Picture. IC220 Set #11: Storage and I/O I/O. Outline. Important but neglected

Big Picture. IC220 Set #11: Storage and I/O I/O. Outline. Important but neglected Big Picture Processor Interrupts IC220 Set #11: Storage and Cache Memory- bus Main memory 1 Graphics output Network 2 Outline Important but neglected The difficulties in assessing and designing systems

More information

Hardware: Input, Processing, and Output Devices

Hardware: Input, Processing, and Output Devices Hardware: Input, Processing, and Output Devices Computer Systems Hardware Components Execution of an Instruction Processing Characteristics and Functions Physical Characteristics of CPU Memory Characteristics

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

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

Hardware: Input, Processing, and Output Devices. A PC in Every Home. Assembling a Computer System

Hardware: Input, Processing, and Output Devices. A PC in Every Home. Assembling a Computer System C H A P T E R 3 Hardware: Input, Processing, and Output Devices A PC in Every Home February 3, 2000 Ford will make available to all 330,000 employees hourly and salaried an HP Pavilion PC, an HP DeskJet

More information

CSCA0102 IT & Business Applications. Foundation in Business Information Technology School of Engineering & Computing Sciences FTMS College Global

CSCA0102 IT & Business Applications. Foundation in Business Information Technology School of Engineering & Computing Sciences FTMS College Global CSCA0102 IT & Business Applications Foundation in Business Information Technology School of Engineering & Computing Sciences FTMS College Global Chapter 2 Data Storage Concepts System Unit The system unit

More information

HP Smart Array Controllers and basic RAID performance factors

HP Smart Array Controllers and basic RAID performance factors Technical white paper HP Smart Array Controllers and basic RAID performance factors Technology brief Table of contents Abstract 2 Benefits of drive arrays 2 Factors that affect performance 2 HP Smart Array

More information

lesson 1 An Overview of the Computer System

lesson 1 An Overview of the Computer System essential concepts lesson 1 An Overview of the Computer System This lesson includes the following sections: The Computer System Defined Hardware: The Nuts and Bolts of the Machine Software: Bringing the

More information

HARD DRIVE CHARACTERISTICS REFRESHER

HARD DRIVE CHARACTERISTICS REFRESHER The read/write head of a hard drive only detects changes in the magnetic polarity of the material passing beneath it, not the direction of the polarity. Writes are performed by sending current either one

More information