Chapter 11 - I/O management and disk scheduling. After studying this chapter, you should be able to: Summarize key categories of I/O devices on computers, discuss the organization of the I/O function, explain some of the key issues in the design of OS support for I/O, analyze the performance implications of various I/O buffering alternatives,. | Chapter 11 I/O Management and Disk Scheduling Dave Bremer Otago Polytechnic, NZ ©2008, Prentice Hall Operating Systems: Internals and Design Principles, 6/E William Stallings These slides are intended to help a teacher develop a presentation. This PowerPoint covers the entire chapter and includes too many slides for a single delivery. Professors are encouraged to adapt this presentation in ways which are best suited for their students and environment. 1 Roadmap I/O Devices Organization of the I/O Function Operating System Design Issues I/O Buffering Disk Scheduling Raid Disk Cache UNIX SVR4 I/O LINUX I/O Windows I/O Beginning with a brief discussion of I/O devices and the organization of the I/O functions. Next examine operating system design issues, including design objectives, and the way in which the I/O function can be structured. Then I/O buffering is examined; The next sections of the chapter are devoted to magnetic disk I/O. We begin by developing a model of disk I/O . | Chapter 11 I/O Management and Disk Scheduling Dave Bremer Otago Polytechnic, NZ ©2008, Prentice Hall Operating Systems: Internals and Design Principles, 6/E William Stallings These slides are intended to help a teacher develop a presentation. This PowerPoint covers the entire chapter and includes too many slides for a single delivery. Professors are encouraged to adapt this presentation in ways which are best suited for their students and environment. 1 Roadmap I/O Devices Organization of the I/O Function Operating System Design Issues I/O Buffering Disk Scheduling Raid Disk Cache UNIX SVR4 I/O LINUX I/O Windows I/O Beginning with a brief discussion of I/O devices and the organization of the I/O functions. Next examine operating system design issues, including design objectives, and the way in which the I/O function can be structured. Then I/O buffering is examined; The next sections of the chapter are devoted to magnetic disk I/O. We begin by developing a model of disk I/O performance and then examine several techniques that can be used to enhance performance. 2 Categories of I/O Devices Difficult area of OS design Difficult to develop a consistent solution due to a wide variety of devices and applications Three Categories: Human readable Machine readable Communications 3 Human readable Devices used to communicate with the user Printers and terminals Video display Keyboard Mouse etc Suitable for communicating with the computer user. Examples include printers and terminals, the latter consisting of video display, keyboard, and perhaps other devices such as a mouse. 4 Machine readable Used to communicate with electronic equipment Disk drives USB keys Sensors Controllers Actuators Suitable for communicating with electronic equipment. Examples are disk drives, USB keys, sensors, controllers, and actuators. 5 Communication Used to communicate with remote devices Digital line drivers Modems Suitable for communicating with remote devices. Examples are digital line .
