1. B.Tech, CS 4th Sem , 2nd year
CS-405:Operating System
Rakhi Arora
Assistant Professor , Department of Computer Science &
Engineering
Unit-1
Topic: Operating System-Types(Part 1)
Lecture Number:3
Jan-July,2022
5. Types of Operating System
CS 405 5
SELO:1,8 <Reference:1>
There are following types of Operating system:-
• Batch Operating System
• Time-Sharing Operating Systems
• Multi-Programming Operating System
• Multiprocessor Systems
• Distributed Operating System
• Real Time Operating System
• Network Operating System
• Clustered Systems.
6. Batch Operating System
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SELO:1,8 <Reference:1>
• In a Batch Operating System, the similar jobs are grouped together into
batches with the help of some operator and these batches are executed one
by one.
8. Batch Operating System
CS 405 8
SELO:1,8 <Reference:1>
CPU
Operating
System
Job 1
Job 2
Job n
Batch 1
Batch 2
Batch n
9. Batch Operating System- Advantages
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SELO:1,8 <Reference:1>
The overall time taken by the system to execute all the programs will be
reduced.
The Batch Operating System can be shared between multiple users.
10. Batch Operating System- Disadvantages
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SELO:1,8 <Reference:1>
• Manual interventions are required between two batches.
• The CPU utilization is low because the time taken in loading and
unloading of batches is very high as compared to execution time.
• If a job gets to enter in an infinite loop, other jobs wait for unknown time.
• Batch systems are costly.
11. Time-Sharing Operating Systems
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SELO:1,8 <Reference:1>
•Multi Tasking System
•More than one processes are being executed at a particular time with the help
of the time-sharing concept.
•A time sharing system allows many users to share the computer resources
simultaneously.
12. Time-Sharing Operating Systems
CS 405 12
SELO:1,8 <Reference:1>
Ready Running
Waiting
New
Job
Job
Completed
I/O
Request
I/O
Completed
Job allocated to
CPU
Allotted time
Over
13. Time-Sharing Operating Systems-Advantages
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SELO:1,8 <Reference:1>
• Since equal time quantum is given to each process, so each process gets
equal opportunity to execute.
• It reduces CPU idle time
14. Time-Sharing Operating Systems-Disadvantages
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SELO:1,8 <Reference:1>
• Process having higher priority will not get the chance to be executed first
because the equal opportunity is given to each process.
15. Multi Programming Operating System
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SELO:1,8 <Reference:1>
•In this the operating system picks up and begins to execute one of the jobs
from memory.
•Once this job needs an I/O operation operating system switches to another job
(CPU and OS always busy).
•If several jobs are ready to run at the same time, then the system chooses
which one to run through the process of CPU Scheduling.
•In Non-multiprogrammed system, there are moments when CPU sits idle and
does not do any work.
•In Multiprogramming system, CPU will never be idle and keeps on
processing.
16. Multi Programming Operating System
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SELO:1,8 <Reference:1>
Operating System
Job 1
Job 2
Job 3
Job 4
Job 5
18. Multi Programming Operating System-Advantages
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SELO:1,8 <Reference:1>
Increase CPU utilization and it never gets idle.
Resources are utilized smartly.
Less response time.
19. Multi Programming Operating System-Disadvantages
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SELO:1,8 <Reference:1>
• CPU scheduling is needed.
• Memory management is required because all types of jobs are stored in
the main memory.
• It is highly complex and sophisticated.
20. Assignment
CS 405 20
1) State the history of operating system.
2) Explain why Windows operating system is one of the most popular
operating systems?
SELO:6
21. Student Effective Learning Outcomes
CS 405 21
1. Ability to solve problems through application of theoretical &
practical concept.
6. Ability to observe and develop sense making, logical skills for
abstract concepts.
8. Ability to understand subject related concepts clearly along with
contemporary issues
23. References
CS 405 23
1. Operating System Concepts” by Silberschatz and Peter Galvin.
2. Andrew S. Tanenbaum, “Modern Operating Systems”, 3/e, Prentice Hall