Operating Systems Lecture Notes

A collection of flashcards covering key concepts, terminology, and definitions related to operating systems as discussed in the lecture.

Operating System (OS)

Software that manages a computer’s resources and provides an interface for users and applications.

KERNEL

The core part of the operating system that manages system resources and allows communication between hardware and software.

Virtualization

The creation of a virtual version of something, such as a virtual operating system or hardware platform.

Reliability

The ability of a system to consistently perform according to its specifications without failure.

Security Policy

A set of rules that define what is permitted in terms of system access and usage.

Application Programming Interface (API)

A set of function calls provided to applications for interacting with the operating system.

Hardware Abstraction Layer (HAL)

An interface that abstracts the hardware components from the operating system, allowing for easier application development.

Performance Metrics

Measurements used to evaluate the efficiency and effectiveness of an operating system, including response time and throughput.

Fairness

How resources are allocated among different applications or users to maintain efficiency.

Portability

The characteristic of an operating system that allows it to run on different hardware without modification.

OS can act as

Referee (manages resources, isolation, communication), illusionist (virtualization), glue (simplifies application design, simplifies hardware and application development)

Logical OS Structure

Applications: Quake, SQL Server, System Utils, Shells, Windowing & graphics

OS: networking, CPU Scheduling, virtual memory, access control. file system, process management, device drivers, hardware specific software

Hardware: disks, cache, physical memory, TLB, Hardware devices