Introduction to Operating Systems - What is an Operating System?
An operating system (OS) does not perform any useful functions, but it does offer an environment within the system in which programs can perform.
An operating system serves as a bridge between the user and the computer system. Without the presence of an Operating System, programs cannot operate. It is the only program on the computer; all other programs are application programs.
When resources are needed, an OS functions as a resource manager, allocating and coordinating resources to specified programs and users. Processors, memory, files, and I/O devices are examples of these resources. Linux, Windows, VMS, OS/400, AIX, and z/OS are some of the most prevalent operating systems. It is in charge of the execution of all types of programs in a computer system.
OS Points of View
The two perspectives of an OS are as follows:
User View: This is the current interface, which is intended for a single user. This allows a user to fully monopolize system resources. It is simple to use, but it performs poorly and wastes a lot of resources.
System View: The System View depicts an operating system as a resource allocator. The operating system (OS) efficiently manages resources, chooses between competing demands, controls application execution, and much more.
Operating System Features
The following are the functions of an operating system:
Starts up the computer.
Manages peripheral devices, does basic computer activities, and so forth…
Provides a graphical user interface.
System resource management that is effective.
Manipulates, stores retrieves and saves data as part of file management.
Error management is performed by it.
An operating system's services
The following are the functions of an operating system:
Primary Memory Management is a term that refers to the management of primary memory.
Processor Management: Determines when and for how long each process receives the CPU.
Storage Management: It manages hard disks and performs storage allocation.
Device Management: Controls the communication between devices via their drivers.
File Management: Manages and keeps track of the system's files and directories.
Unauthorized access is prevented.
Control over system performance: Improves response time and reduces call waits.
Job accounting Keeps track of how much time and resources tasks and users spend on them.
Aids for error detection: Error detection and debugging
Coordination between software and users: assigns and coordinates compilers, interpreters, and assemblers, among other things.
Operating System Characteristics
The following are characteristics of a good operating system:
Make computers more user-friendly.
Aids in the efficient utilization of resources.
It evolves, allowing new features to be added without disrupting existing services.
It should provide the highest possible throughput.
Operating System Characteristics
The following are some significant characteristics of an operating system:
Batch processing: Jobs are processed in batches.
Multitasking: Performing numerous tasks at the same time.
Multiprogramming: This technique runs multiple programs in parallel on the same CPU.
Distributive environment: A distributive environment is made up of multiple separate processors.
Interactivity: This allows a user to communicate with a computer system.
Real-time system: Real-time systems are dedicated embedded systems.
Spooling: It collects data from various I/O jobs and stores it in a buffer or on a disk.
What is the purpose of an operating system?
The two functions of an operating system are as follows:
- Manages system resources, users, and tasks by allocating processes and managing system resources.
- Creates a link between the computer hardware and the programmer, making program creation, coding, and debugging even easier.
The Evolution of Operating Systems
Operating Systems Types
The following are some examples of common operating systems:
- Batch Operating System: This system runs jobs in batches without the need for operator intervention.
- Time-sharing operating system: Multiple users share computer resources to ensure that they are used to their full potential.
- Distributed operating system: Controls multiple computers while making them appear to be one.
- Network operating system: A network operating system that connects machines with different operating systems over a shared network.
- Real-time operating system: For applications with strict reaction times or deadlines.
Scheduling Procedures
A process is a program that is run by an operating system. The process of scheduling a process into different states, such as ready, waiting, and running, is known as process scheduling. Preemptive and non-preemptive scheduling are the two types of scheduling.
Algorithms for Scheduling
Processes on the CPU are scheduled using a scheduling method. The following are some of the most often used process scheduling algorithms:
- Scheduling on a first-come, first-served basis (FCFS)
- SJN Scheduling (Shortest-Job-Next Scheduling)
- Prioritization of Tasks
- Remaining Time is the least amount of time.
- Round Robin (RR) Scheduling
- Scheduling Multiple-Level Queues
- Scheduling of Multilevel Feedback Queues
- 8. Highest Response Ratio
Benefits of Using an Operating System
The following are some of the benefits of using an operating system:
Aids in the improvement of system efficiency and the reduction of complexity.
Every component is self-contained and self-contained. As a result, one's failure has no bearing on the other.
It serves as a link between the hardware and software.
Access to hardware without the need to write huge applications.
People can simply exchange data with other users.
It is now easy to install programs.
Can be readily updated and changed regularly.
Many operating systems are open source, which means they are free to use.
Hardware complexity is hidden.
Allows for easier programming and multitasking.
Disadvantages of the operating system
The following are some of an OS's drawbacks:
Although some operating systems are free, some are not. Typically, operating systems with GUI capabilities and other built-in features are relatively costly.
The majority of the time, operating systems are vulnerable to virus attacks. A user may unintentionally download harmful software packages, which might slow down the OS's performance.
Because the language in which they are written isn't obvious and well defined, most operating systems are complex. This makes it harder for a user to find a solution to a problem.
If the operating system crashes, the entire system will crash.
Summary
An operating system (OS) does not perform any useful functions, but it does offer an environment within the system in which programs can perform valuable tasks. An operating system can be viewed from two perspectives: user and system. The technique of arranging a process into multiple phases is known as process scheduling. Processes on the CPU are scheduled using a scheduling method.
