tailieunhanh - Lecture Operating system concepts - Chapter 3: Operating-system structures

Chapter 3 is concerned with the operating-system interfaces that users (or at least programmers) actually see: system calls. The treatment is somewhat vague since more detail requires picking a specific system to discuss. This chapter is best supplemented with exactly this detail for the specific system the students have at hand. Ideally they should study the system calls and write some programs making system calls. This chapter also ties together several important concepts including layered design, virtual machines, Java and the Java virtual machine, system design and implementation, system generation, and the policy/mechanism difference. | Chapter 3: Operating-System Structures I System Components I Operating System Services I System Calls I System Programs I System Structure I Virtual Machines I System Design and Implementation I System Generation Operating System Concepts Silberschatz, Galvin and Gagne 2002 Common System Components I Process Management I Main Memory Management I File Management I I/O System Management I Secondary Management I Networking I Protection System I Command-Interpreter System Operating System Concepts Silberschatz, Galvin and Gagne 2002 Process Management I A process is a program in execution. A process needs certain resources, including CPU time, memory, files, and I/O devices, to accomplish its task. I The operating system is responsible for the following activities in connection with process management. ✦ Process creation and deletion. ✦ process suspension and resumption. ✦ Provision of mechanisms for: ✔ process synchronization ✔ process communication Operating System Concepts Silberschatz, Galvin and Gagne 2002 Main-Memory Management I Memory is a large array of words or bytes, each with its own address. It is a repository of quickly accessible data shared by the CPU and I/O devices. I Main memory is a volatile storage device. It loses its contents in the case of system failure. I The operating system is responsible for the following activities in connections with memory management: ✦ Keep track of which parts of memory are currently being used and by whom. ✦ Decide which processes to load when memory space becomes available. ✦ Allocate and deallocate memory space as needed. Operating System Concepts Silberschatz, Galvin and Gagne 2002 File Management I A file is a collection of related information defined by its creator. Commonly, files represent programs (both source and object forms) and data. I The operating system is responsible for the following activities in connections with file management: ✦ File creation and .