Introduction to OS Introduction to OS & &

Computer organizationComputer organization

© Dr. Aiman Hanna© Dr. Aiman HannaDepartment of Computer Science Department of Computer Science

Concordia University Concordia University Montreal, CanadaMontreal, Canada

22

Introduction to OSIntroduction to OS What is an OS?What is an OS?

Software:Software:System softwareSystem softwareApplication softwareApplication software

33

ApplicationSoftware

SystemSoftware

Hardware

(a) End UserView

(b) ApplicationProgrammer

View

(c) OS ProgrammerView

ApplicationSoftware

ApplicationSoftware

SystemSoftware

SystemSoftware

Hardware Hardware

cutsave

printsend

malloc()fork()

open()read-disk

track-mousestart-printer

Software/HardwareSoftware/Hardware

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Different Software/Hardware Different Software/Hardware InterfacesInterfaces

Hardware Resources

Trusted OS(Abstract Resources)

Software-Hardware Interface

OS Interface

System Software(More Abstract Resources)

API

Application Software

Human-Computer Interface

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Introduction to OSIntroduction to OS Different Kinds of OSDifferent Kinds of OS

BatchBatchTimesharingTimesharingReal-timeReal-timeDedicated (Embedded)Dedicated (Embedded) Distributed Distributed Mobile Mobile ……etc.etc.

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Basic Functions of OSBasic Functions of OS Resource AbstractionResource Abstraction

Resource SharingResource Sharing

Resource Isolation Resource Isolation

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Advantages of SharingAdvantages of Sharing MultiprogrammingMultiprogramming

MultitaskingMultitasking

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Computer OrganizationComputer Organization Von Neumann Architecture Von Neumann Architecture

ALUALUControl UnitControl UnitI/O DevicesI/O Devices……..

99

Memory OrganizationMemory Organization IR, MDR, PC, …IR, MDR, PC, …

Fetch cycleFetch cycle

Interrupt cycleInterrupt cycle

1010

Where is this week coverage in Where is this week coverage in the textbook?the textbook?

Chapter 1:Chapter 1:Sections 1.1, 1.3, 1.4, 1.6, 1.7, 1.8, 1.9 , 1.11 & Sections 1.1, 1.3, 1.4, 1.6, 1.7, 1.8, 1.9 , 1.11 &

1.131.13

Permanently Skip: Sections 1.10 & 1.12Permanently Skip: Sections 1.10 & 1.12

Note: Parts of these permanently skipped sections will actually be Note: Parts of these permanently skipped sections will actually be discussed in class and during lab times; however, you can still skip discussed in class and during lab times; however, you can still skip them when reading/studying for the course. them when reading/studying for the course.