Hard Disks and I/O Polytechnic University CS2214 11/25/03.

Slides:



Advertisements
Similar presentations
IT253: Computer Organization
Advertisements

Hard Drives Storing Information 1 Byte at a Time.
CPE 442 io.1 Introduction To Computer Architecture CpE 442 I/O Systems.
OPERATING SYSTEMS CS3530 Summer 2014 OPERATING SYSTEMS CS3530 Summer 2014 Input/Output System Chapter 9.
Computer Hardware Preview the exam questions. RAM SECONDARY STORAGE CPU.
CS4432: Database Systems II Data Storage - Lecture 2 (Sections 13.1 – 13.3) Elke A. Rundensteiner.
04/18/2007CSCI 315 Operating Systems Design1 Mass Storage Structure Notice: The slides for this lecture have been largely based on those accompanying the.
13.2 Disks Mechanics of Disks Presented by Chao-Hsin Shih Feb 21, 2011.
1  1998 Morgan Kaufmann Publishers Chapter 8 Storage, Networks and Other Peripherals.
1  1998 Morgan Kaufmann Publishers Chapter 8 Interfacing Processors and Peripherals.
1 Lecture 26: Storage Systems Topics: Storage Systems (Chapter 6), other innovations Final exam stats:  Highest: 95  Mean: 70, Median: 73  Toughest.
1 Storage Hierarchy Cache Main Memory Virtual Memory File System Tertiary Storage Programs DBMS Capacity & Cost Secondary Storage.
CS4432: Database Systems II Lecture 2 Timothy Sutherland.
CPSC 231 Secondary storage (D.H.)1 Learning Objectives Understanding disk organization. Sectors, clusters and extents. Fragmentation. Disk access time.
Hard Drive / Hard Disk Functions of hard disk
Hard Drive (HDD): Device located in a computer tower/case that stores and retrieves program files and data files; also known as the C:drive. Computer.
By: Akram Ali. What Are Hard Drive Disks?  Hard Drives are the main storage device for all the data on your computer  It is where you store all your.
CS4432: Database Systems II Data Storage (Better Block Organization) 1.
Hard Drives “ Hard disks store digital information in a relatively permanent form.” --howstuffworks.com.
Hard Drives Non-Volatile Storage. Hard Drives Hard Drives (HD) The primary storage device in a computer system.
HARD DISK. Unutrasnjost  The best way to understand how a hard disk works is to take a look inside. (Note that OPENING A HARD DISK RUINS IT, so this.
How Hard Disks Work. Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes. They.
I/O – Chapter 8 Introduction Disk Storage and Dependability – 8.2 Buses and other connectors – 8.4 I/O performance measures – 8.6.
CS 111 – Aug – 1.3 –Information arranged in memory –Types of memory –Disk properties Commitment for next day: –Read pp , In other.
Hard Drives Ryan2005. What it Does Stores info magnetically hard “platter” holds info.
Components & Mechanism. People & Computers Hard Disk What purpose does it serve?
Disks Chapter 5 Thursday, April 5, Today’s Schedule Input/Output – Disks (Chapter 5.4)  Magnetic vs. Optical Disks  RAID levels and functions.
STORAGE DEVICES Presentation By: Saurabh Mishra. A data storage device is a device for recording (storing) information (data). CD, Hard Disk and Flash.
Binary and Hard Disk Aslin Izmitli PEOPLE Program.
GENERAL INFORMATION Invented in 1950's on mainframe computers with 20 inches diameter with only few megabytes of data. Originally called 'Fixed Disc'
I/O and Disk Scheduling CS Spring Overview Review of I/O Techniques I/O Buffering Disk Geometry Disk Scheduling Algorithms RAID.
Describing Storage Devices  Storage terms  Media is the material storing data  Storage devices manage the media  Magnetic devices use a magnet  Optical.
I/O Computer Organization II 1 Introduction I/O devices can be characterized by – Behavior: input, output, storage – Partner: human or machine – Data rate:
August 1, 2001Systems Architecture II1 Systems Architecture II (CS ) Lecture 9: I/O Devices and Communication Buses * Jeremy R. Johnson Wednesday,
© 2005 Pearson Addison-Wesley. All rights reserved Figure 2.1 This chapter focuses on key hardware layer components.
Programming for GCSE Topic 5.1: Memory and Storage T eaching L ondon C omputing William Marsh School of Electronic Engineering and Computer Science Queen.
Storage Hardware Devices Presented by Hector Arreola Valentin Kifumbi Keely Ritchie-Boland.
DMBS Internals I. What Should a DBMS Do? Store large amounts of data Process queries efficiently Allow multiple users to access the database concurrently.
Lecture 40: Review Session #2 Reminders –Final exam, Thursday 3:10pm Sloan 150 –Course evaluation (Blue Course Evaluation) Access through.
Computer Architecture CST 250
CS2100 Computer Organisation Input/Output – Own reading only (AY2015/6) Semester 1 Adapted from David Patternson’s lecture slides:
Auxiliary Memory Magnetic Disk:
Csci 136 Computer Architecture II – IO and Storage Systems Xiuzhen Cheng
Disk Basics CS Introduction to Operating Systems.
CS 101 – Sept. 28 Main vs. secondary memory Examples of secondary storage –Disk (direct access) Various types Disk geometry –Flash memory (random access)
Operating Systems (CS 340 D) Princess Nora University Faculty of Computer & Information Systems Computer science Department.
Operating Systems (CS 340 D) Princess Nora University Faculty of Computer & Information Systems Computer science Department.
DMBS Internals I. What Should a DBMS Do? Store large amounts of data Process queries efficiently Allow multiple users to access the database concurrently.
Disk Average Seek Time. Multi-platter Disk platter Disk read/write arm read/write head.
Section 13.2 – Secondary storage management. Index 13.2 Disks Mechanics of Disks The Disk Controller Disk Access Characteristics.
Magnetic Disk Rotational latency Example Find the average rotational latency if the disk rotates at 20,000 rpm.
CPSC 231 Secondary storage (D.H.)1 Learning Objectives Understanding disk organization. Sectors, clusters and extents. Fragmentation. Disk access time.
10/15: Lecture Topics Input/Output –Types of I/O Devices –How devices communicate with the rest of the system communicating with the processor communicating.
1 Lecture 16: Data Storage Wednesday, November 6, 2006.
1 Components of the Virtual Memory System  Arrows indicate what happens on a lw virtual address data physical address TLB page table memory cache disk.
Computer Maintenance Hard Drives
TYPES OF MEMORY.
Chapter 10: Mass-Storage Systems
Computer Components.
Sarah Diesburg Operating Systems CS 3430
Backing Store.
Hard Drives.
Computer hardware f1031 – computer hardware.
Disks and Files DBMS stores information on (“hard”) disks.
Lecture 11: DMBS Internals
Introduction I/O devices can be characterized by I/O bus connections
Operating Systems (CS 340 D)
Input-output I/O is very much architecture/system dependent
Chapter 11: Mass-Storage Systems
Networks & I/O Devices.
Presentation transcript:

Hard Disks and I/O Polytechnic University CS /25/03

Input/Output

I/O contd. I/O bandwidth measurements How much data can be moved through system in a given time? E.g. supercomputer applications How many I/O operations can we do per unit of time? E.g. National Income Tax Service

I/O Characteristics Behavior Input (read once) Output (write only, cannot be read) Storage (can be reread and usually rewritten) Partner Human or machine or other end? Data Rate Peak rate at which data can be transferred between I/O device and main memory or processor.

I/O Characteristics Contd. DeviceBehaviorPartnerData Rate (KB/sec) KeyboardInputHuman.01 Line Printer OutputHuman1.00 ModemInput/ Output Machine Magnetic Disk StorageMachine2, ,000

Common Hard Disk Parameters Data rate - Number of bytes per second that a drive can deliver to the CPU. Seek time - Amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Capacity - Number of bytes disk can hold

Inside A Hard Disk Sealed aluminum box with controller electronics attached to one side. Electronics control the read/write mechanism and the motor that spins the platters. Electronics are all contained on a small board that detaches from rest of the drive.

Inside A Hard Disk Contd. The platters spin at 3,600 or 7,200 rpm when the drive is operating. These platters are manufactured to amazing tolerances and are mirror- smooth. The arm that holds the read/write heads is controlled by the mechanism in the upper-left corner, and is able to move the heads from the hub to the edge of the drive. The arm and its movement mechanism are extremely light and fast.

Inside A Hard Disk Contd.

Hard Disk Access Times Seek time Rotational time Transfer time Controller time

Problem What is the average time to read or write 512 byte sector for a disk rotating at 5400 RPM? Average seek time is 12ms, transfer rate is 5MB/sec and controller overhead is 2ms. Average disk access time = T seek +T Rotational + T Transfer + T Controller =12ms + 5.6ms+.5KB/5MB/sec +2ms = = 19.7 ms.

Hard Disk Animation Animation