Operating Systems

What happens when a computer is turned on?
FACEPrep · 5 min read
While a computer has several programs running in it, what happens when a computer is turned on? When a computer is turned on, a specific program called an operating system is started. An operating system is responsible for the proper functioning of the computer.
Operating Systems | Process Management
FACEPrep · 5 min read
A program in execution is called a process which is managed by process management. For example, when a program is written in any of the programming languages like C, C++, Java and compiled, a binary code is created by the compiler. Here the original code and the Binary code come under programs. Whereas the procedure of running the binary code becomes a process in the process management.
Operating Systems | CPU Scheduling
FACEPrep · 5 min read
CPU Scheduling of processes or work is done to complete the work on time. This typical CPU scheduling process includes both the I/O time and CPU time. MS-DOS is an uniprogramming system in which time spent waiting for I/O is wasted where CPU is free during this time in CPU Scheduling process. Whereas in multiprogramming systems, when a process is waiting for I/O another process can use CPU during CPU Scheduling process. This can be possible only in CPU Scheduling process.
Operating Systems | Process Scheduler
FACEPrep · 5 min read
The process scheduler aim is to assign processes that are to be executed by the processor or processors over time. Process scheduler sees that execution is done in a way that it meets system objectives such as throughput, response time and processor efficiency. Process scheduler divides this scheduling activity into three separate functions in many systems named as long, medium, and short-term scheduling.
Operating Systems | FCFS Scheduling Program | Part 1
FACEPrep · 5 min read
In FCFS scheduling algorithm, the concept is to find the average waiting time and the average turn around time with the burst time of given n processes. First come, first served (FCFS), is also known as First in, first out (FIFO) which is the simplest scheduling algorithm. The FCFS algorithm's job is to simply queue the processes in the order that they actually arrive in the ready queue.
Operating Systems | FCFS Scheduling Program | Part 2
FACEPrep · 5 min read
FCFS Scheduling for the processes with same arrival time is discussed earlier in the Program for FCFS Scheduling|Part 1. In this part, FCFS Scheduling when the processes have different arrival times will be discussed. In FCFS Scheduling algorithm, the concept is to find the average waiting time and the average turn around time with their given burst times and arrival times of n processes. The FCFS scheduling algorithm's job is to simply queue the processes in the order that they actually arrive in the ready queue.
Operating Systems | SJF Scheduling Program(Non- preemptive)
FACEPrep · 5 min read
SJF is a Shortest job first or shortest job next scheduling algorithm that picks the waiting process which has the smallest execution time to be executed next. SJF scheduling algorithm is also called as a Greedy Algorithm. SJF Scheduling algorithm is a non-preemptive algorithm.
Operating Systems | Round Robin Scheduling Program
FACEPrep · 5 min read
Round Robin Scheduling algorithm is a CPU scheduling algorithm. Round Robin Scheduling is used as one of the most common technique as a core in CPU scheduling. In this Round Robin scheduling algorithm, each process will be assigned a fixed time slot in a cyclic way.
Operating Systems | Priority Scheduling Program
FACEPrep · 5 min read
Priority scheduling one of the most common scheduling algorithms used in batch systems. In this priority scheduling algorithm, Each process is assigned with a priority and the process with the highest priority is to be executed first and so on. Here processes with the same priority are to be executed on first come first served basis.
Operating Systems | Convoy Effect
FACEPrep · 5 min read
The phenomenon in which the whole Operating System slows down due to some of the few slow processes in the system is called Convoy Effect. This convoy effect is interrelated with the First Come First Serve (FCFS) algorithm.
Operating Systems | Process Synchronization
FACEPrep · 5 min read
Process Synchronization means sharing system resources by processes in a such a way that, Concurrent access to shared data is handled thereby minimizing the chance of inconsistent data. Maintaining data consistency demands mechanisms to ensure synchronized execution of cooperating processes.Process Synchronization was introduced to handle problems that arose while multiple process executions.
Operating Systems | Critical Section
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A way to avoid trouble concerning shared storage is to find the same way to prevent more than one process from reading and writing the shared data simultaneously. The part of the program where the shared memory is accessed is called the critical section.To prohibit race conditions and inconsistent results, one must recognize the codes in the critical sections in each process or thread.
Operating Systems | Inter Process Communication(IPC)
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Inter process communication(IPC) means the processes to communicate with each other while they are running. IPC allows processes to synchronize their action without sharing the same address space.
Operating Systems | Memory Management
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In this article we will discuss about memory management, logical address, physical address and swapping.
Operating Systems | System calls
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In this article we will discuss about system calls in detail.
Operating Systems | Peterson's Algorithm
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In this article we will discuss about peterson's algorithm.
Operating Systems | System design and Implementation
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In this article we will discuss about the system design and implementation.
Operating Systems | Operations on Files
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In this article we will discuss about various operations on the files in operating systems.
Operating Systems | Readers-Writers Problem
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In this article we will discuss about the reader's writer's problem.
Operating System | Banker's Algorithm
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In this article we will discuss about banker's algorithm
Operating Systems | Fragmentation and Compaction
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In this article we will discuss about external and internal fragmentation along with compaction.
Operating Systems | Evaluation of Scheduling algorithms
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In this article we will discuss about the evaluation of scheduling algorithms by analytic evaluation, simulations and implementation of algorithms.
Operating Systems | Concept of Directories
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In this article we will discuss about the concept of directories.
Operating Systems | Deadlock Introduction
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In this article we will discuss about deadlock, its representation, prerequisites and strategies.
Operating Systems | Deadlock Detection And Recovery
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In this article we will discuss about how to detect and recover from a deadlock.
Operating Systems | Deadlock Prevention And Avoidance
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In this article we will discuss about the prevention and avoidance of deadlocks
Operating Systems | Principles of security design
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In this article we will discuss about the principles of security design
Operating Systems | Spooling and Device Reservation
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In this article we will discuss about the concept called spooling and device reservation
Operating Systems | Concept of Threads
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In this article we will discuss about the concept of threads.
Operating Systems | User Level thread Vs Kernel Level thread
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In this article we will see discuss about the user level and kernel level threads.
Operating Systems | Multithreading models
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In this article we will discuss about the multithreading models called many to one, many to many, and one to one model.
Operating Systems | Partition allocations
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In this article we will discuss about the contiguous allocation scheme which has single and multiple partition allocations in it.
Operating Systems | Virtual memory
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In this article we will discuss about virtual memory.
Operating Systems | Trashing
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In this article we will discuss about the topic thrashing.
Operating Systems | Paging
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In this article we will discuss about paging concept.
Operating Systems | Segmentation
FACEPrep · 5 min read
In this article we will discuss about the concept of segmentation.
Operating Systems | Kernel Data Structure
FACEPrep · 5 min read
In this article we will discuss about the kernel data structure in detail.
Operating Systems | Page Replacement Algorithms
FACEPrep · 5 min read
In this article we will discuss about the page replacement algorithms namely OPT, FIFO, SC, NRU, LRU, etc
Operating Systems | Disk Space Management
FACEPrep · 5 min read
In this article we will discuss about the disk space management.
Operating Systems | Disk Scheduling Algorithms
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In this article we will discuss about the disk scheduling algorithms.
Operating Systems | Disk Errors and Bad blocks
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In this article we will discuss about disk errors and bad blocks.
Operating Systems | Concept of Files
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In this article we will discuss about files and its attributes.
Operating Systems | File Allocation Methods
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In this article we will discuss about three types of file allocation methods.
Operating Systems | Backup and Cache
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In this article we will discuss about backup and cache.
Operating Systems | Security and Protection
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In this article we will discuss about threats and attacks on the security.
Operating Systems | Protection Mechanisms
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In this article we will discuss about protection mechanisms like domain,access matrix and encryption.
Operating Systems | System Threats
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In this article we will discuss about system threats called computer worms and viruses.
Operating Systems | Producer-Consumer Problem
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In this article we will discuss about producer-consumer problem also known as bounded buffer problem.
Operating Systems | Dining Philosopher's Problem
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In this article we will discuss about the dining philosophers problem.
Operating Systems | Error Handling
FACEPrep · 5 min read
In this article we will discuss about error handling in kernel I/O Subsystem.