Operating systems, control systems and translation

Learning objectives

Describe how an operating system hides hardware complexity from users and programs, and outline its functions: memory management, file systems, device management, process scheduling, security, accounting, the graphical user interface, virtualization and networking

Compare first-come first-served, round-robin, priority and multilevel queue scheduling, and work out the order in which a given set of processes would run and wait under each

Evaluate polling against interrupt handling for keyboards and mice, network traffic, disk input and output, and embedded and real-time systems, considering how often events occur, processor overhead, battery or mains power, predictability, latency and security

(HL) Explain how the operating system shares processor time, memory and devices between tasks running at the same time, and how contention for resources can produce deadlock

(HL) Describe the sensors, controller, control algorithm, actuators, transducers and feedback of a control system, distinguish open-loop from closed-loop control, and explain its use in thermostats, lifts, washing machines, traffic signals, irrigation, home security, automatic doors and autonomous vehicles

(HL) Evaluate compilers and interpreters on how and when errors are reported, translation time, execution speed and portability, and explain how bytecode interpreters and just-in-time compilation combine the two for rapid development, performance-critical and cross-platform work