tailieunhanh - Ebook Operating systems - Internals and designprinciples (9/E): Part 2

Part 2 book “Operating systems - Internals and designprinciples” has contents: I/O management and disk scheduling, file management, embedded operating systems, virtual machines, operating system securit, cloud and IoT operating systems. | Part 5 Input/Output and Files Chapter I/O Management and Disk Scheduling I/O Devices Organization of the I/O Function The Evolution of the I/O Function Direct Memory Access Operating System Design Issues Design Objectives Logical Structure of the I/O Function I/O Buffering Single Buffer Double Buffer Circular Buffer The Utility of Buffering Disk Scheduling Disk Performance Parameters Disk Scheduling Policies RAID RAID Level 0 RAID Level 1 RAID Level 2 RAID Level 3 RAID Level 4 RAID Level 5 RAID Level 6 Disk Cache Design Considerations Performance Considerations UNIX SVR4 I/O Buffer Cache Character Queue Unbuffered I/O UNIX Devices Linux I/O Disk Scheduling Linux Page Cache Windows I/O Basic I/O Facilities Asynchronous and Synchronous I/O Software RAID Volume Shadow Copies Volume Encryption Summary Key Terms, Review Questions, and Problems 505 505 5/9/17 4:32 PM 506   Chapter 11 / I/O Management and Disk Scheduling Learning Objectives 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. • Understand the performance issues involved in magnetic disk access. • Explain the concept of RAID and describe the various levels. • Understand the performance implications of disk cache. • Describe the I/O mechanisms in UNIX, Linux, and Windows. Perhaps the messiest aspect of operating system design is input/output. Because there is such a wide variety of devices and applications of those devices, it is difficult to develop a general, consistent solution. We begin with a brief discussion of I/O devices and the organization of the I/O function. These topics, which generally come within the .