OS Lecture 2 Types of Operating System

 Types Of Operating System



Video Link : click

(1). Types of Operating System

     1. Uni-programming OS
     2. Multi-programming OS
     3. Multi-Tasking OS
     4. Multi-User OS
     5. Multi-processing OS
     6. Embedded OS
     7. Real-Time OS
     8. Hand-held Device OS

 

1. Uni-programming OS : 

     OS allows only one process to reside in  main memory ( RAM ). Single process cannot keep CPU and I/O devices busy simultaneously. Not a good or better CPU utilization

2. Multi-programming OS :

     OS allows multiple process to reside in main memory. Better CPU utilization than Uni-programming. 
     

Degree of multiprogramming :

 Number of running programs ( processes ) in main memory. As the degree of multiprogramming increases , CPU utilization also increases up to a certain limit.


 multi-programming OS : Types 

    1. preEmptive - A process can be forcefully taken out of CPU.
    2. non-preEmptive - a process runs on CPU till its wish. either process terminates or goes for I/O operation


3. Multi-tasking OS  / ( Time-sharing OS):

     Extension of multi-programming OS in which processes execute in round-robin fashion.

4. Multi-User OS : 

     This OS allows multiple users to access single system simultaneously. windows is not multi-user OS where linux, unix is multi-users OS.

5. Multi-Process OS : 

     This OS is used in computer systems with multiple CPU's.
     Types : 
          1. Tightly coupled ( shared-memory )
          2. Loosely coupled ( Distributed System )

6. Embedded OS : 

     An OS for embedded computer systems
     Designed for a specific purpose, to increase functionality and reliability for achieving a specific task. User interaction with OS is Minimum

7. Real-Time OS : 

     Real time operating system (RTOS) are used in environments where a large number of events, mostly external to the computer system, must be accepted and processed in a short time or within certain deadlines.
example : OS used for rocket launching.
Every process have a deadline.
Types : 
     1. Hard RTOS : Strict about deadline
     2. Soft RTOS : some relaxation about deadline

8. Hand-held Device OS : 

     OS used in hand-held devices

     



Popular Posts

java:17: error: local variables referenced from a lambda expression must be final or effectively final count ++ ;

Image
 Modifying variables inside java lambdas. Integer list[] = {1,2,3,4,5,6,7,8}; int index = 0; Arrays.asList(list).forEach(e -> { System.out.println(e+" at index "+index); index++; }); Error : maze2.java:22: error: local variables referenced from a lambda expression must be final or effectively final System.out.println(e+" at index "+index); ^ maze2.java:23: error: local variables referenced from a lambda expression must be final or effectively final index++; ^ Solution : Integer list[] = {1,2,3,4,5,6,7,8}; int[] index = {0}; Arrays.asList(list).forEach(e -> { System.out.println(e+" at index "+index[0]); index[0]++; }); Output : 1 at index 0 2 at index 1 3 at index 2 4 at index 3 5 at index 4 6 at index 5 7 at index 6 8 at index 7
View post ��

Family Tree Project in Java

Image
Creating Family tree in java .  Trees are such an important structure in computer science. But what more important tree, than our family tree? ❤️   👨‍👩‍👧‍👦   ❤️    Made this simple program in java to implement family tree. Java File import java.util.*; class Person { String name; boolean married; String wife; int noOfChild; Person[] childs; public Person(String name){ this.name = name; } public Person(String name,boolean married,String wife,Person[] childs,int noOfChild) { this.name = name; this.married = married; this.wife = wife; this.childs = childs; this.noOfChild = noOfChild; } public Person(String name , boolean married,String wife) { this.name = name; this.married = married; this.wife = wife; } } class familyTree { static int population; static Scanner input = new Scanner...
View post ��

Creating basic tic tac toe android app using java

Image
 Marvel Tic Tac Toe Android Game ( Java ) In this blog I we will create basic android app. We will be coding in java.   package com.example.batvsiron ; import androidx.appcompat.app.AppCompatActivity ; import android.os.Bundle ; import android.util.Log ; import android.view.View ; import android.widget.Button ; import android.widget.GridLayout ; import android.widget.ImageView ; import android.widget.TextView ; import android.widget.Toast ; import java.util.Arrays ; public class MainActivity extends AppCompatActivity { int active = 0 ; public int [][] winningPosition = { { 0 , 1 , 2 } , { 3 , 4 , 5 } , { 6 , 7 , 8 } , { 0 , 3 , 6 } , { 1 , 4 , 7 } , { 2 , 5 , 8 } , { 0 , 4 , 8 } , { 2 , 4 , 6 } } ; public int [] moves = { 111 , 111 , 111 , 111 , 111 , 111 , 111 , 111 , 111 } ; public int checkWinning () { for ( int [] arr : winningPosition ) { ...
View post ��