Operating System Changes and Structure

An operating system structure that combines elements of both monolithic and layered systems, often found in modern operating systems like Mac OS X.

The ability of an operating system to execute multiple tasks concurrently, switching between them rapidly to create the illusion of simultaneous execution.

A type of process synchronization mechanism that uses a lock to protect critical sections of code, ensuring only one thread can access them at a time.

Using multiple processors or cores to execute a single task concurrently, dividing the work among available processors for faster execution.

A memory allocation technique used in the Linux kernel for managing small memory blocks, offering efficiency and speed advantages.

A type of memory allocation technique in Linux for handling small memory blocks, focusing on simplicity and efficiency in memory-constrained environments.

An operating system that is specifically designed to handle real-time tasks with strict timing requirements, often used in systems like industrial control.

A storage device that uses flash memory for data storage, offering faster read and write speeds compared to traditional hard disk drives.

A method of transferring data directly between a peripheral device and memory, bypassing the CPU for faster I/O operations.

A technique used to handle I/O requests by interrupting the CPU after each byte of data transfer, suitable for small data transfers but inefficient for large data volumes.

A type of system architecture where multiple components can communicate directly with each other without having to share a single bus, improving efficiency and parallelism.

A common structure found in computers where various components like CPU, memory, and I/O devices interact with each other through a set of connections.

A type of solid-state storage that is popular in cameras, PDAs, robots, and increasingly in general-purpose computers. It is slower than DRAM but doesn't require power to retain data.

A type of non-volatile memory that uses DRAM with battery backup. It offers the speed of DRAM and retains data even when the system is off (as long as the battery lasts).

A component that manages the flow of data between the CPU and I/O devices. Each controller handles specific device types.

A software component that interacts with the device controller and provides a uniform interface to the operating system. It allows the operating system to communicate with various devices.

A small, fast memory that temporarily stores frequently accessed data. It sits between the CPU and main memory, speeding up data retrieval.

A process that involves loading the appropriate registers within the device controller to initiate an I/O operation. The controller then interprets the registers to determine the action to be taken.

The transfer of data between a peripheral device and its local buffer storage. It is controlled by the device controller.

The part of the operating system responsible for managing I/O devices. It ensures the reliability and performance of the system, adapting to the varying nature of different devices.

An operating system design where the CPU is never idle, switching between tasks constantly. It's like a lawyer working on multiple cases at once, always busy.

A type of operating system that allows users to interact with the computer system while it's running, giving the illusion of individual dedicated access. It works like a shared computer system.

An interactive computer system enables bi-directional communication between the user and the system, allowing for direct interaction and prompt feedback.

A process is a running program in memory. It usually runs for a short time before it either finishes or requires I/O operations.

I/O refers to input and output operations, where data is taken into (input) or sent out from (output) the computer system.

Interactive I/O involves user interaction with the system, typically through input devices like keyboards, mice, or touch screens and output displayed on the screen.

CPU scheduling is a technique used in operating systems to manage the allocation of the CPU among multiple processes competing for its resources.

A computer system with multiple interconnected computers that work together to provide a single, unified computing environment.

Multiprogramming is a technique where multiple programs reside in memory and are executed concurrently using CPU scheduling. It allows for efficient utilization of the CPU's time.

A program or a set of programs that manages the computer's hardware resources and provides a platform for other programs to run.

The ability of an operating system to execute multiple programs or tasks concurrently, switching between them rapidly to create the illusion of simultaneous execution.

A collection of jobs (programs and data) waiting to be allocated memory and executed by the operating system.

The process of switching the CPU's attention between different jobs in memory, allowing multiple jobs to share the CPU and run concurrently.

An important aspect of multiprogramming where the operating system manages and allocates memory space to different jobs, ensuring they have enough space to execute.

A type of operating system structure where all system components are organized in a single, monolithic code base, including kernel and application software.

A type of operating system structure where the system components are organized in layers, with each layer providing services to the layer above it and using services from the layer below it.

A special mode of operation where the operating system has full control of the computer's hardware and resources, allowing it to manage tasks and provide services to user processes. Kernel mode is also known as supervisor mode, system mode, or privileged mode.

A mode of operation where user programs execute, with limited access to the system's hardware and resources. User mode execution is restricted to ensure the operating system's stability and security.

A bit within the computer's hardware that determines the current mode of operation – either kernel or user mode. This bit is used to manage access to system resources and prevent unauthorized actions.

A mechanism where a user program requests a specific service from the operating system. This involves a transition from user mode to kernel mode so the operating system can handle the request securely.

The process of switching between kernel and user mode, typically triggered by system calls or interrupts. This switch is essential for managing the interaction between user programs and the operating system.