Lecture # 7. Topics Storage Techniques of Bits Storage Techniques of Bits Mass Storage Mass Storage Disk System Performance Disk System Performance File.

Slides:



Advertisements
Similar presentations
A device that reads and writes data on a magnetic disk or tape. For writing, the surface of the disk or tape is moved past the read/write head. By discharging.
Advertisements

Storage Devices Primary storage: is the storage provided
Chapter 4 Storing Information in a Computer Peter Nortons Introduction to Computers.
10/5: Data storage concepts What is data storage? Types of storage –magnetic, optical, magneto-optical, solid state Storage characteristics Magnetic storage:
Peripheral Storage Devices
Chapter 4 – Page 1QM-130Dr. Sulaiman Al-Rafee Chapter 4 – Storage Chapter Summary Properties of Storage Systems Magnetic Disks Optical Disks Other types.
Computer Studies Today Chapter 18 1 »Two main types of secondary storage devices: –Magnetic storage devices –Optical storage devices.
Professor Michael J. Losacco CIS 1150 – Introduction to Computer Information Systems Secondary Storage Chapter 7.
Lesson 9 Types of Storage Devices.
Storage Devices.
Types Of Storage Device
Professor Michael J. Losacco CIS 1110 – Using Computers Storage Chapter 6.
Section 5a Types of Storage Devices.
Data Storage Lecture 3 CSCI 1405, CSCI 1301 Introduction to Computer Science Fall 2009.
Chapter 1 Data Storage. 2 Chapter 1: Data Storage 1.1 Bits and Their Storage 1.2 Main Memory 1.3 Mass Storage 1.4 Representing Information as Bit Patterns.
1 CS222: Principles of Database Management Fall 2010 Professor Chen Li Department of Computer Science University of California, Irvine Notes 01.
Storage Devices and Media
Storage device.
Computer SCIENCE Data Representation and Machine Concepts Section 1.3
Mass storage (secondary storage)
Bits and Data Storage. Basic Hardware Units of a Computer.
Storage.
Information Technology Storage Devices Prof. Adnan Khalid.
1 Part I: Machine Architecture 4 A major process in the development of a science is the construction of theories that are confirmed or rejected by experimentation.
Lecture on Electronic Memories. What Is Electronic Memory? Electronic device that stores digital information Types –Volatile v. non-volatile –Static v.
1 Secondary Storage Management Submitted by: Sathya Anandan(ID:123)
Storing Data: Electronic Filing Cabinets What You Will Learn Difference between memory and storage How storage media are categorized Measuring a storage.
STORAGE IN COMPUTER By- Upendra Sharma. STORAGE DEVICE We can use storage device to save data in computer. It is divided in two parts- 1. Primary memory.
Your Interactive Guide to the Digital World Discovering Computers 2012.
Pengantar Teknologi Informasi dan Ilmu Komputer Information Technology and Data Representation PTIIK- UB.
Components & Mechanism. People & Computers Hard Disk What purpose does it serve?
 Secondary storage (or external memory) - is not directly accessible by the CPU. Secondary storage does not loose the data when the device is powered.
Chapter 1: Data Storage.
TheTeacher Computing Data Storage Computing. TheTeacher Computing Primary Storage One of the fundamental properties of a computer is that it can store.
Overview of Physical Storage Media
Data Storage. 3 types of storage to remember ROM RAM Secondary or backing storage.
Storing data – Storage devices and media. What is a storage device?  A storage device is any device used in a computer to store information.  A storage.
2.1 Operating System Concepts Chapter 2: Computer-System Structures Computer System Operation Storage Structure Storage Hierarchy Hardware Protection General.
Chapter 1 Data Storage © 2007 Pearson Addison-Wesley. All rights reserved.
Storage Hardware Devices Presented by Hector Arreola Valentin Kifumbi Keely Ritchie-Boland.
Data Storage Introduction to computer, 2nd semester, 2010/2011 Mr.Nael Aburas Faculty of Information Technology Islamic.
Chapter 1 Data Storage © 2007 Pearson Addison-Wesley. All rights reserved.
Data Storage © 2007 Pearson Addison-Wesley. All rights reserved.
Storage of Data Instructions and data are held in main memory which is divided into millions of addressable storage.
Copyright © Curt Hill Disk Basics Structure and Characteristics of Secondary Storage.
By : Reem Hasayen. A storage device is a hardware device capable of storing information. There are two types of storage devices used in computers 1. Primary.
More on data storage and representation CSC 2001.
Data Storage © 2007 Pearson Addison-Wesley. All rights reserved.
Lecture 5: 9/10/2002CS149D Fall CS149D Elements of Computer Science Ayman Abdel-Hamid Department of Computer Science Old Dominion University Lecture.
Chapter 1 Data Storage © 2007 Pearson Addison-Wesley. All rights reserved.
Memory The term memory is referred to computer’s main memory, or RAM (Random Access Memory). RAM is the location where data and programs are stored (temporarily),
Section 13.2 – Secondary storage management. Index 13.2 Disks Mechanics of Disks The Disk Controller Disk Access Characteristics.
نظام المحاضرات الالكترونينظام المحاضرات الالكتروني Main Memory Read Only Memory (ROM)
Data Storage and Querying in Various Storage Devices.
Chapter 1: Data Storage.
Computer Science: An Overview Eleventh Edition
Chapter 2: Computer-System Structures
Backing Store.
Introduction to Computing
Chapter 1 Data Storage.
Secondary Storage Devices
Computer Application Waseem Gulsher
Lesson 9 Types of Storage Devices.
Networks & I/O Devices.
Storage and Multimedia
Presentation transcript:

Lecture # 7

Topics Storage Techniques of Bits Storage Techniques of Bits Mass Storage Mass Storage Disk System Performance Disk System Performance File File Storing Fractions Storing Fractions Data Compression Data Compression Communication Errors Communication Errors

Storage of Bits Gate: A device that computes a Boolean operation Gate: A device that computes a Boolean operation Often implemented as (small) electronic circuits in which voltage levels indicate 0s and 1s Often implemented as (small) electronic circuits in which voltage levels indicate 0s and 1s Provide the building blocks from which computers are constructed Provide the building blocks from which computers are constructed VLSI (Very Large Scale Integration) VLSI (Very Large Scale Integration)

Figure 1.2 A pictorial representation of AND, OR, XOR, and NOT gates as well as their input and output values

Mass Storage In computing, mass storage refers to the storage of large amounts of data in a persisting and machine-readable fashion. In computing, mass storage refers to the storage of large amounts of data in a persisting and machine-readable fashion. Storage media for mass storage include hard disks, floppy disks, flash memory, magnetic disks, Optical Disks (CDs, DVDs), magnetic tape etc Storage media for mass storage include hard disks, floppy disks, flash memory, magnetic disks, Optical Disks (CDs, DVDs), magnetic tape etc

Mass storage includes devices with removable and non-removable media. Mass storage includes devices with removable and non-removable media. It does not include random access memory (RAM), which is volatile in that it loses its contents after power loss. It does not include random access memory (RAM), which is volatile in that it loses its contents after power loss.

Advantage over RAM Less volatile Less volatile Large Storage Capacity Large Storage Capacity

Mass Storage On-line versus off-line On-line versus off-line Typically larger than main memory Typically larger than main memory Typically less volatile than main memory Typically less volatile than main memory Typically slower than main memory Typically slower than main memory

Mass Storage Systems Magnetic Systems Magnetic Systems Disk Disk Tape Tape Optical Systems Optical Systems CD CD DVD DVD Flash Drives Flash Drives

Magnetic Disk Thin disk with magnetic coating Thin disk with magnetic coating Read/ write Heads Read/ write Heads Head traverses circle called Track Head traverses circle called Track Tracks divided into Sectors Tracks divided into Sectors Information of Tracks and Sectors setup by formatting disk Information of Tracks and Sectors setup by formatting disk

Magnetic Disk Lower Capacity Systems e.g Floppy Disk Lower Capacity Systems e.g Floppy Disk High Capacity Systems e.g Hard Disk High Capacity Systems e.g Hard Disk Hard Disk contains 5-10 disks mounted on a spindle rigidly Hard Disk contains 5-10 disks mounted on a spindle rigidly To allow for Faster Speed the Head is floating above the surface To allow for Faster Speed the Head is floating above the surface Head Crash due to dust particles Head Crash due to dust particles

Disk System Performance Seek Time: Time required by the R/W head to move from one track to another Seek Time: Time required by the R/W head to move from one track to another Rotational Delay / Latency Time: Rotational Delay / Latency Time: Half the time required by the disk to make one complete rotation Half the time required by the disk to make one complete rotation Access Time: Seek Time + Rotational Delay Access Time: Seek Time + Rotational Delay Transfer Rate: rate at which data transferred to another disk Transfer Rate: rate at which data transferred to another disk

Figure 1.9 A magnetic disk storage system

Figure 1.10 Magnetic tape storage

Figure 1.11 CD storage

Files File: A unit of data stored in mass storage system File: A unit of data stored in mass storage system Fields and keyfields Fields and keyfields Physical record versus Logical record Physical record versus Logical record Buffer: A memory area used for the temporary storage of data (usually as a step in transferring the data) Buffer: A memory area used for the temporary storage of data (usually as a step in transferring the data)

Figure 1.12 Logical records versus physical records on a disk