Operating System Roles: Referee and Resource Manager

This lecture discusses the operating system's role as a referee in managing resources and ensuring security. It begins by explaining the three main functions of an operating system: fault isolation, resource sharing, and communication. The instructor emphasizes the importance of fault isolation, which prevents programs from interfering with each other, thus maintaining system stability. The lecture illustrates how the operating system schedules resources and determines which program executes at any given time, ensuring fair resource distribution among multiple applications. The communication aspect is also highlighted, showcasing how the operating system facilitates interaction between programs through primitives like pipes and sockets. An illustrative example is provided, demonstrating how multiple instances of a program can run concurrently, leading to non-deterministic output due to the operating system's scheduling decisions. The lecture concludes with a discussion on how the operating system penalizes processes for illegal actions, such as memory access violations, which result in segmentation faults, thereby reinforcing the importance of the operating system's referee role.