Computer Engineering Department - MEFGI

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Operating System140702

Hemang KothariAssistant Professor

Computer Engineering Department MEFGI, Rajkot.

Email: hemang.kothari@marwadieducation.edu.in

Computer Engineering Department - MEFGI

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Teaching Scheme

• 140702 Operating System

• Theory - 4

• Practical - 2

• Credit - 6

• Final Exam - 70

• Term work -30

• Internal Practical - 50

• Total – 150 Marks

Reference Books:1. Modern Operating Systems -By Andrew S. Tanenbaum (PHI)2. Operating System – Internals & Design Principles -By William Stallings (PHI)3. Operating Systems By D.M.Dhamdhare (TMH)4. Unix System Concepts & Applications By Sumitabha Das (TMH)5. Unix Shell Programming By Yashwant Kanitkar

Computer Engineering Department - MEFGI

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Expectation

• Smiling Face

• Attendance

• Interactive Session

• Enjoy the joy of learning

Computer Engineering Department - MEFGI

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Methodology

• Why Need to learn

• What Definition, Meaning, is all about

• How Performance, Implementation, Simulation, Development

Do Not Worry, We have only 4 Assignment

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Operating System

• Introduction to our day to day life

• Introduction to system

• Component of System

• Working of system

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Ahh .. Lots of Work

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Solution

• Better Management of Resources.

• Enough Resources

• Time Scheduling

• Understand the priority of work

• Proper Planning

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Module 1: Input Output Management• Principles Of Input / Output H/W

• Principles Of Input / Output S/W

• Device Independent I/O Software Disks

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I / O Devices

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How OS will be friend ?????

• OS controls I/O devices => • Issue commands, • handles interrupts, • handles errors

• Provide easy to use interface to devices• Hopefully device independent

• First look at hardware, then software• Emphasize software• Software structured in layers• Look at disks

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Principles Of Input / Output H/W

• Two types of I/O devices- block, character• Block- can read blocks independently of one another• Hard disks, CD-ROMs, USB sticks• 512-32,768 bytes

• Character-accepts characters without regard to block structure• Printers, mice, network interfaces

• Not everything fits, e.g. clocks don’t fit• Division allows OS to deal with devices in device independent manner• File system deals with blocks

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Device Controllers

• I/O unit has 2 components-mechanical, electronic (controller)• Controller is a chip with a connector which plugs into cables to device• Disk• Disk might have 10,000 sectors of 512 bytes per track • Serial bit stream comes off drive• Has preamble, 4096 bits/sector, error correcting code• Preamble has sector number, cylinder number, sector size….

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Example System

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Mange More

Disks

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Continue .. Disk Controller• Controller assembles block from bit stream, does error correction,

puts into buffer in controller• Blocks are what are sent from a disk• The controller’s job is to convert the serial bit stream into a block of

bytes and perform any error correction necessary. The block of bytes is typically first assembled, bit by bit, in a buffer inside the controller. After its checksum has been verified and the block declared to be error free, it can then be copied to main memory.

Computer Engineering Department - MEFGI

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Actor(OS) and Supporting Actor(Controller)

How OS Deal with Controller ?

Don’t Worry , Next time we will study