Transcript operating system - GH Raisoni Polytechnic, Nagpur

OPERATING SYSTEM(17512)
SESSION
:
COURSE
:
SEMESTER
:
SUBJECT CODE :
FACULTY
:
EMAIL
2015-16
COMPUTER TECHNOLOGY
FIFTH
17512
PANKAJ G. INGOLE
DEPARTMENT OF CM
GHRP, NAGPUR
: [email protected]
TEACHING AND EXAMINATION
SCHEME
Teaching Scheme
Examination Scheme
TH
TU
PR
PAPER
HRS
TH
PR
OR
TW
TOTA
L
03
----
02
03
100
----
----
25@
125
NOTE :
Two Class tests each of 25 Marks ( PTT – I & PTT – II )
Unit tests ( Chapter wise )
Assignments ( Chapter wise )
SYLLABUS
REFERENCE BOOK
Text book for Theory :
Operating System Concepts – Eighth Edition
Silberschatz and Galvin, Addison-Wesley Inc.
Reference book for Practical :
Unix Concepts and programming
Sumitabha Das, Tata McGraw Hill
UNIT I
CONTENTS
LECTURES
MARKS
Introduction:
Objectives:
•Distinguish between various generation
computer.
•Classify different types of operating system.
of
1.1 Operating System - Evaluation, Generations
1st, 2nd, 3rd
1.2 Different Types of Operating systems- Batch
operating system,
Multi Programmed, Multitasking,Time Shared OS.
Multiprocessor Systems, Distributed Systems,
Cluster Systems,
Real time systems.
4
12
LECTURE 1 & 2
UNIT 1
LECTURE I & 2 : CHAPTER I
TOPICS
Operating System – Evaluation
 Generations of operating System – 1st, 2nd,
3rd

What is OS ?
O
P
R
A
T
I
N
G
S
Y
S
T
E
M
How do I use them?
How do I manage them?
What is OS ?
Interface between humans & computers
Interface between software & hardware
An OS is a software (a very complex one!)
that makes the hardware usable by
humans/software
 Hardware provides “raw computing power”
 OS makes the computing power
conveniently available to users, by managing
the hardware carefully to achieve good
performance
 OS is a “Manager” of resources!



History of Computers
Before the 1500s, in Europe,
calculations were made with an
abacus
◦ Invented around 500BC,
available in many cultures
(China, Mesopotamia, Japan,
Greece, Rome, etc.)
 In 1642, Blaise Pascal (French
mathematician,
physicist,
philosopher)
invented
a
mechanical calculator called
the Pascaline
 None of these machines had
memory, and they required
human intervention at each
step

In 1822 Charles Babbage (English
mathematician,
philosopher),
sometimes called the “father of
computing” built the Difference
Engine
 Machine designed to automate
the computation (tabulation) of
polynomial functions (which are
known
to
be
good
approximations of many useful
functions)
◦ Based on the “method of
finite difference”
◦ Implements some storage
 In 1833 Babbage designed the
Analytical Engine, but he died
before he could build it
◦ It was built after his death,
powered by steam

Generation of Computers
First Generation (1946-59)
 Second Generation(1957-64)
 Third Generation(1965-70)
 Fourth Generation(1970-90)
 Fifth Generation(1990 till date)

First
Second
Generation Generation
Technology
Size
Vacuum
Tubes
Filled whole
buildings
Transistors
Filled half a
room
Third
Generation
Fourth
Generation
Integrated
Circuits(
multiple
transistors)
Microchips
( Billions of
transistors)
Smaller
Tiny-Palm Pilots is
as powerful as old
building sized
computer
Generation 1 : ENIAC
The ENIAC (Electronic Numerical Integrator and Computer) was
unveiled in 1946: the first all-electronic, general-purpose digital
computer
Generation 2 : IBM7094
Generation 3 : Integrated Circuits
Generation 4 : VLSI

Improvements to IC technology
made it possible to integrate more
and more transistors in a single chip
◦ SSI (Small Scale Integration): 10-100
◦ MSI (Medium Scale Integration): 1001,000
◦ LSI (Large Scale Integration): 1,00010,000
◦ VLSI (Very Large Scale Integration):
>10,000
Microprocessors
Generation 5?
The term “Generation 5” is used sometimes
to refer to all more or less “sci fi” future
developments
Voice recognition
Artificial intelligence
Quantum computing
Bio computing
Nano technology
Learning
Natural languages
LECTURE 3
UNIT 1
LECTURE 3 : CHAPTER I
TOPICS
Different types of operating systems

Batch Operating System

Multi programmed

Multitasking
Early Batch System
bring cards to 1401
read cards to tape
put tape on 7094 which does
computing
put tape on 1401 which prints output
Batch Operating System





In Batch processing same type of jobs batch
(BATCH- a set of jobs with similar needs)
together and execute at a time.
The OS was simple, its major task was to
transfer control from one job to the next.
The job was submitted to the computer
operator in form of punch cards. At some later
time the output appeared.
The OS was always resident in memory. (Ref.
Fig. next slide)
Common Input devices were card readers and
tape drives.
Common output devices were line printers,
tape drives, and card punches.
 Users did not interact directly with the
computer systems, but he prepared a job
(comprising of the program, the data, & some
control information).

OS
User
Program
Area
Multi programmed System





Multiprogramming is a technique to execute
number of programs simultaneously by a single
processor.
In Multiprogramming, number of processes
reside in main memory at a time.
The OS picks and begins to executes one of the
jobs in the main memory.
If any I/O wait happened in a process, then CPU
switches from that job to another job.
Hence CPU in not idle at any time.
OS
Job 1
Job 2
Job 3
•Figure dipicts the layout of
multiprogramming system.
• The main memory consists
of 5 jobs at a time, the CPU
executes one by one.
Advantages:
•Efficient memory utilization
Job 4
•Throughput increases
Job 5
•CPU is never idle,
performance increases.
so
Multitasking/Time Sharing System





Time sharing, or multitasking, is a logical
extension of multiprogramming.
Multiple jobs are executed by switching the
CPU between them.
In this, the CPU time is shared by different
processes, so it is called as “Time sharing
Systems”.
Time slice is defined by the OS, for sharing CPU
time between processes.
Examples: Multics, Unix, etc.,
LECTURE 4
UNIT 1
LECTURE 4 : CHAPTER I
TOPICS
Different types of operating systems
Multiprocessor System
Distributed System
Cluster Systems
Real Time Systems
Multiprocessor System
Multiprocessor systems with more than one
CPU in close communication.
 Tightly coupled system – processors share
memory and a clock; communication usually
takes place through the shared memory.
 Advantages of Multiprocessor system:
◦ Increased throughput
◦ Economical
◦ Increased reliability
 graceful degradation
 fail-soft systems


Symmetric multiprocessing (SMP)
◦ Each processor runs an identical copy of the
operating system.
◦ Many processes can run at once without
performance deterioration.
◦ Most modern operating systems support SMP

Asymmetric multiprocessing
◦ Each processor is assigned a specific task;
master processor schedules and allocates
work to slave processors.
◦ More common in extremely large systems
Symmetric Multiprocessing Architecture
Distributed System
Distribute the computation among several
physical processors.
 Loosely coupled system – each processor has
its own local memory; processors communicate
with
one
another
through
various
communications lines, such as high-speed buses
or telephone lines.
 Advantages of distributed systems.
◦ Resources Sharing
◦ Computation speed up – load sharing
◦ Reliability
◦ Communications

Cluster Systems

Like multiprocessor systems, but multiple
systems working together
◦ Usually sharing storage via a storage-area
network (SAN)
◦ Provides a high-availability service which
survives failures
 Asymmetric clustering has one machine
in hot-standby mode
 Symmetric clustering has multiple nodes
running applications, monitoring each other
Cluster Systems
Real Time Systems

A system is said to be Real Time if it is
required to complete it’s work & deliver it’s
services on time.
Example – Flight Control System
◦ All tasks in that system must execute on time.
 Non Example – PC system

Hard and Soft Real time system

Hard Real Time System
◦ Failure to meet deadlines is fatal
◦ Example : Flight Control System

Soft Real Time System
◦ Late completion of jobs is undesirable but not
fatal.
◦ System performance degrades as more & more
jobs miss deadlines
◦ Example : Live video streaming, Online
Databases
MSBTE Asked Questions
1. What is operating system? Explain the generations of
computer system. Sum-2011 (4M)
2. Explain in detail various generations of operating system.
Sum-2012 (8M),Win-2010(4M),Win-2014(4M)
3. Define operating system. State different types of operating
system. Win-2009 (4M), Sum- 2010(4M)
4. List any four functions of operating system. Sum2010(4M), Sum-2014(4M),Win-2014(4M)
5. Differentiate between multiprogramming and multitasking.
Sum-2009(4M), Sum-2010(4M), Win-2012(4M).
6. Describe real time system. State any two examples of its
applications. Sum-2009(4M), Win-2009(4M), Win2010(4M), Sum-20013(4M), Win-2013(4M), Sum2014(4M),Win-2014(4M)
7. Explain Batch processing operating system. Sum-2009(4M),
Sum-2013(4M),Win-2014(2M)
8. Explain Multiprocessor system concept. Win-2009(4M), Sum2011(4M), Sum-2014(4M),Win-2014(2M)
9. Explain Distributed system in detail. Sum-2010(4M), Sum2011(4M), Sum-2012(4M)
10. Describe Multiprogramming and Multitasking. WIn-2010(4M),
Sum-2014(4M)
11. Describe time sharing system along with example. Win2010(4M),Win-2013(4M)
12. Differentiate between time sharing system and real time system.
Sum-2011(4M)
13. What is Multitasking operating system? State advantages of
multitasking operating system. Win-2011(4M),Win-2013(4M)
14.What is meant by Clustered system? Sum-2012(4M).
15. List any four system components and explain any two. Win2013(4M)