Computer Architecture Supporting Operating Systems
Learn about the computer architecture that supports operating systems, including its components and functionalities.
Why Start With Architecture? Operating system functionality fundamentally depends upon the architectural features of the computer Architectural support can greatly simplify – or complicate – OS tasks Early PC operating systems (DOS, MacOS) lacked virtual memory in part because the architecture did not support it
More Generally: Hardware Interrupts External Event has happened – like device I/O OS needs to check it out. Process stops what it’s doing, invokes OS, which handles the interrupt.
Computer architecture so far Single program working with local memory What do we have to add to support a modern operating system? Isolation between processes System abstraction – Hide details about underlying hardware Resource management – CPU, memory, disk, network, ...
OS reacts to changes in hardware, and can motivate changes. What the OS can do is dictated in part by the architecture. Architectural support can greatly simplify or complicate the OS. Memory management: OS coordinates allocation of memory and …
Other process problems include infinite loop, processes modifying each other or the operating system Dual-mode operation allows OS to protect itself and other system components
Operating System Architectures: Past, Present, Future Learning objectives: Explain how OS functionality is orthogonal to where you place services relative to processor modes. Describe some alternative ways to structure the operating system. Pontificate about the future of …
CS 537 Lecture 2 Computer Architecture and Operating Systems Michael Swift OS Tasks What is the role of the OS regarding hardware? What does the OS need from hardware to perform this role? Computer Hardware Organization
What is an Operating System? “The one program running at all times on the computer” is the kernel. Everything else is either a system program (ships with the operating system) or an application program. A process is a program in execution. It is a unit of work within the system. Program is a passive entity, process is an active entity.
Hardware supports a scheme that allows us to tell apart the trusted programmer (operating system designer) from untrusted programmers (regular users). Most architectures support at least two modes of operation: kernel mode and user mode