Operating System Foundations

Lecturer: Dr J.M. Bacon (jmb@cl.cam.ac.uk)

No. of lectures: 16

This course is a prerequisite for Distributed Systems, Introduction to Security and Computer Design.

Aims

The aims of this course are to introduce the basic principles of computer systems organisation and operation; to show how hardware is controlled by program at the hardware/software interface; to outline the basic OS resource management functions: memory, file, device (I/O) and process management; and to explore the need for, principles of and implementation of concurrency control.

Lectures

Part I. Computer organisation [4 lectures]

• Computer design; the hardware and its interfaces. Bus/memory/CPU organisation. Representation of numbers and characters; instruction sets and addressing. Operation of a simple computer; the fetch-execute cycle.

• Device management. I/O devices and interfaces; polling and interrupts. The general exception mechanism for interrupts, errors, system calls, memory management. Character and DMA interfaces.

Part II. Operating system structure and functions [6 lectures]

• Operating system evolution and structure.

• Process management. Creating virtual processor abstractions. Support for processes (or threads) in operating systems. CPU scheduling.

• Memory management. Processes in memory. Logical addresses. Segmented memory. Paged memory: concepts, internal fragmentation, page tables. Paged segments.

• File management. File concept. Directory and storage services. File names and meta-data. Directory name-space: hard and soft links. File operations. Access control. Existence and concurrency control.

Part III. Concurrency control [3-4 lectures]

• I/O management- aspects. Process-device synchronisation. Process - process mutual exclusion and synchronisation via I/O buffers.

• Multi-threaded processes. User threads and kernel threads.

• System structure and interprocess communication (IPC). Requirements for concurrency control; System structure; Shared memory mechanisms; Semaphores and their implementation; examples; No-shared-memory mechanisms.

• Composite concurrent operations. Problem of deadlock. Introduction to transaction concept.

Part IV. Case studies [2-3 lectures]

• Case studies. Aspects of Unix and Windows NT/2000 will be used throughout as examples and consolidated in summarising lectures if time allows.

Objectives

At the end of the course students should

• be prepared for hardware and architecture courses

• understand the interaction of software and hardware

• understand how memory, devices (I/O) and files are managed

• understand the concepts of process, thread and address space

• understand the need for and implementation of concurrency control

• understand the design of widely used operating systems at a high level of abstraction

Recommended books

For hardware/architecture please browse the books recommended for Part IA hardware courses and for Computer Design.

Bacon, J. (1997). Concurrent Systems. Addison-Wesley (2nd ed.).
Bacon, J. & Harris, T. (2003). Operating Systems: Distributed and concurrent software design. Addison-Wesley. (Will supersede Concurrent Systems.)
Tanenbaum, A.S. (1992). Modern Operating Systems. Prentice-Hall.
Silberschatz, A., Galvin, P.B. & Gagne, G. (2001). Operating System Concepts. Addison-Wesley (6th ed.).

For further detail on the case studies:

Bach, M.J. (1986). Design of the Unix Operating System. Prentice-Hall.
Leffler, S.J. et al. (1989). The Design of the 4.3BSD Unix Operating System. Addison-Wesley.
McKusick M.K. et al. (1996). The Design and Implementation of the 4.4BSD Unix Operating System. Addison-Wesley.
Soloman D.A. & Russinovich, M.E. (2000). Inside Micosoft Windows 2000. Microsoft Press. (3rd ed.)