Operating Systems Fundamentals Flashcards
What is an Operating System (OS)?
An OS manages hardware and software resources, acting as an intermediary between users and computer hardware.
What are the main objectives of an operating system?
Convenience
Efficiency
Ability to Evolve
What are the four key components of a computer system?
Hardware
Operating System
Application Programs
Users
What are the main stages in the evolution of operating systems?
Serial Processing
Simple Batch Systems
Multiprogrammed Batch Systems
Time-Sharing Systems
What is serial processing in operating systems?
A method where jobs are executed one after another without any overlapping.
What is the primary feature of a batch processing system?
Jobs are batched together and executed sequentially, often using a monitor to control the sequence.
What is multiprogramming in an OS?
A technique where multiple programs are kept in memory simultaneously to maximize CPU utilization.
What is time-sharing in an operating system?
An approach where CPU time is divided among multiple users, giving the illusion of simultaneous execution.
What is process management in an operating system?
Handling the creation, scheduling, and termination of processes.
What are the five states of a process in an OS?
New
Ready
Running
Waiting (Blocked)
Terminated
What is a Process Control Block (PCB)?
A data structure in the OS that contains process-related information such as process state, program counter, and memory management information.
What is context switching in an OS?
The process of saving the state of a running process and loading the state of another process.
What is the goal of CPU scheduling?
To maximize CPU utilization and system performance by selecting processes to execute.
Name three common CPU scheduling algorithms.
First Come, First Served (FCFS)
Shortest Job First (SJF)
Round Robin (RR)
What is the main drawback of FCFS scheduling?
It can cause a convoy effect, where short processes wait for long processes to complete.
What is the advantage of SJF scheduling?
It minimizes average waiting time, but predicting the next CPU burst is challenging.
What is the key feature of Round Robin scheduling?
Each process gets a fixed time slice (quantum) to execute, improving response time.
How does priority scheduling work?
Processes are executed based on priority, with higher-priority processes running first.
What is a deadlock in an operating system?
A situation where two or more processes are waiting for each other to release resources, resulting in a standstill.
How can deadlocks be prevented?
By ensuring that at least one of the necessary conditions (mutual exclusion, hold and wait, no preemption, circular wait) is not met.
What is the primary goal of memory management?
To allocate and manage the computer’s primary memory efficiently.
What is paging in memory management?
A technique where memory is divided into fixed-size pages to minimize fragmentation.
What is virtual memory?
A memory management technique that gives the illusion of a larger main memory by using disk space.
What is I/O management in an OS?
Managing input and output devices and the data transfer between them and the CPU.
What is the purpose of a device driver?
To provide an interface between the OS and hardware devices.
What is Direct Memory Access (DMA)?
A technique where data is transferred directly between I/O devices and memory without CPU intervention.
What is a system call?
A request from an application to the OS to perform low-level services.
What does file system management involve?
Organizing and storing files on storage devices while maintaining metadata and access control.
What is bootstrapping in an OS?
The process of loading the operating system into memory when the computer is powered on.
What is the kernel in an OS?
The core component that manages system resources and communication between hardware and software.
Why use an API wrapper instead of direct system calls?
For portability and easier access to system functionalities.
What are virtual machines (VMs)?
Software that emulates hardware to run multiple OS environments on one physical machine.
What are the two modes in dual-mode operation?
User Mode and Kernel Mode - to protect the OS from malicious or faulty programs.
What is IPC?
A set of techniques for exchanging data between processes.
Why is process synchronization important?
To ensure that processes sharing resources do not interfere with each other.
