Operating System Tutorial

What is Operating System Evolution of Operating System Types of Operating System Functions of Operating System What is Kernel and Types of Kernel Operating System Properties Operating System Services Components of Operating System Needs of the Operating System Linux Operating System Unix Operating System Ubuntu Operating System What is DOS Operating System Difference Between Multi-programming and Multitasking What is Thread and Types of Thread Process Management Process State What is Process Scheduler and Process Queue What is Context Switching What is CPU Scheduling Scheduling Algorithm FCFS (First-come-First-Serve) Scheduling SJF (Shortest Job First) Scheduling Round-Robin CPU Scheduling Priority Based Scheduling HRRN (Highest Response Ratio Next) Scheduling Process Synchronization Lock Variable Mechanism TSL Mechanism Turn Variable Mechanism Interested Variable Mechanism What is Producer-Consumer Problem What is Semaphore in Operating System Monitors in Operating System What is Deadlock Deadlock Avoidance Strategies for Handling Deadlock Deadlock Prevention Deadlock Detection and Recovery Resource Allocation Graph Banker’s Algorithm in Operating System Fixed Partitioning and Dynamic Partitioning Partitioning Algorithms What is Paging and Segmentation What is Demand Paging What is Virtual Memory Disk Scheduling Algorithms FCFS and SSTF Disk Scheduling Algorithm SCAN and C-SCAN Disk Scheduling Algorithm Look and C-Look Disk Scheduling Algorithm File in Operating System File Access Methods in Operating System File Allocation Method Directory Structure in Operating System Difference between C-LOOK and C-SCAN Difference between Rotational Latency and Disk Assess Time Trap vs Interrupt How to implement Monitors using Semaphores N-Step-SCAN Disk Scheduling Why is it critical for the Scheduler to distinguish between I/O-bound and CPU-bound programs Difference between C-SCAN and SSTF Difference between SCAN and FCFS Difference between Seek Time and Disk Access Time Difference between SSTF and LOOK

Operating System Services

The Operating System provides various types of services:  

  1. I/O operation
  2. Program execution
  3. File system manipulation
  4. Communication
  5. Error Handling
  6. Resource allocation
  7. Accounting
  8. Protection
Operating System Services

1. I/O Operation: - To execute a program, needs I/O, which consists of a file, or I/O device. Due to the protection and effectiveness, users are not able to manage the I/O device, so the operating system helps the user to perform I/O operations such as read and write operations in a file. The Operating system offers the facility to access the I/O device when needed.

2. Program execution: - Operating System is responsible for loading a program into memory and then executing that program. Operating System helps us to manage different tasks from user programs to the system programs such as file server, name server, printer spooler, etc. Each of these tasks is sum-up as a process. A process may consist of complete execution context like data to manipulate, OS resources in use, registers, code to execute, etc.

The operating system performs the following tasks for program management:

  • Executes the program.
  • Load the program into memory.
  • Operating system offers a procedure for process synchronization.
  • Operating system offers a procedure for deadlock handling.
  • Operating system offers a method for process communication.
  • Manages the program’s execution.

 3. File System Manipulation

A file is a collection of information. For long term storage computer stores, the file is placed on the disk, and disk is the secondary storage. For example - Magnetic disk, CD, DVD, Magnetic tape. Each storage media has different properties or capabilities such as capacity, speed, data access, and data transfer method.

For easy and effective usage, the File system is organized in the form of directories, and the directories contain files and other directions.

The operating system performs the following activities for File System Manipulation.

  • It offers an interface so that we can easily create and delete files.
  • It offers an interface to create and delete directories.
  • It offers an interface so that we can create a backup of the file.
  • With the help of the operating system, we can access the program for performing an operation on a file.

4. Communication

The Operating system offers the facility of communication. The Process requires information exchange with another process. For executing a process on the same computer or different computer systems, it communicates with the help of the operating system. Communication between the processes is done with the help of message passing and shared memory.

5. Error Handling

The Operating system provides the service of error handling. An error may arise anywhere, like in I/O devices, Memory, CPU, and in the user program. The Operating system takes appropriate action for each error to ensure consistency and correct computing.

6. Resource allocation

In a system, when multiple jobs are executing concurrently, then resource allocation must be needed for each job. Resources include main memory storage, file storage, CPU cycles, and I/O devices. The operating system handles every type of resource by using schedulers. With the help of CPU scheduling, the task of resource allocation can be performed.

7. Accounting

Accounting service of the operating system helps to keep track of the system usage means which users use the resources for how much time and what type of resources are used by the system.

8. Protection: - If the computer system has different users and permits the concurrent execution of the various processes, then it is must to protect the processes from one another’s activities.