PC Operating Systems Hardware

1. PC Operating Systems Hardware Guide to Operating Systems Third Edition

2. Objectives After reading this chapter and completing the exercises you will be able to: • Explain operating system hardware components • design type, speed, cache, address bus, data bus, control bus, and CPU scheduling • Describe basic features and system architecture • Identify the basic features and characteristics of popular PC operating systems • Understand how hardware components interact with operating systems Guide to Operating Systems, Third Edition

3. Understanding CPUs • System architecture • number and type of CPUs in the hardware • communication routes – buses • The CPU • performs the computational and logic work • Most modern PCs have one such chip - single-processor computers • There are computers that have multiple CPUs • Two to 64 or more • multiprocessor computers Guide to Operating Systems, Third Edition

4. Understanding CPUs (continued) • CPU hardware elements: • Design type – Speed • Cache – Address bus • Data bus – Control bus • CPU Scheduling Guide to Operating Systems, Third Edition

5. Design Type • Two general CPU designs: • CISC (Complex Instruction Set Computer) • RISC (Reduced Instruction Set Computer) • Main difference • number of different instructions the chip can process • Instruction set • the list of commands the CPU can understand and carry out Guide to Operating Systems, Third Edition

6. Design Type (continued) • This type of processor is called a Complex Instruction Set Computer (CISC) CPU • The CISC CPU offers advantages and disadvantages • Advantage • need only general-purpose hardware to carry out commands Guide to Operating Systems, Third Edition

7. Design Type (continued) • Disadvantages • CISC design includes the complexity of hardware needed to perform many functions • the complexity of on-chip software needed to make the hardware do the right thing • the need to continually reprogram the on-chip hardware • complex operations that a CISC CPU carries out slow it down because all sorts of hardware on the chip must be set up to perform specific functions Guide to Operating Systems, Third Edition

8. Design Type (continued) • The RISC CPU design • requires very little setup because it has hardware on the chip that is specially designed and optimized to perform particular functions • pipelining - allows the processor to operate on one instruction at the same time it is fetching one or more subsequent instructions Guide to Operating Systems, Third Edition

9. Design Type (continued) • Explicitly Parallel Instruction Computing (EPIC) • joint project by Intel and Hewlett Packard • processor handles massive numbers of operations simultaneously • enables a single processor to execute as many as 20 operations at a time • Advantage • using three instructions per word, EPIC enables the processor to work much faster • instructions can be combined into instruction groups Guide to Operating Systems, Third Edition

10. Speed • Internal clock speed is the most obvious indicator • clock provides this to make sure that all the chips know what to expect at what time • tells you how many clock pulses, or ticks, are available per second • External clock speed • chips also must be able to communicate with the other chips in the computer • lower clock speed to communicate with the rest of the computer Guide to Operating Systems, Third Edition

11. Cache • Cache memory built into the CPU chip • extremely fast—it typically runs at the same speed as the processor—and therefore expensive • If processor needs a number stored in the cache memory on the CPU, it probably won’t have to wait to obtain that number • referred to as Level 1 (L1) cache Guide to Operating Systems, Third Edition

12. Cache (continued) • Some CPUs have one or two more levels of cache memory, which are typically on a separate chip • Level 2 (L2) cache • Level 3 (L2) cache • Cache controller • predicts what data will be needed, and makes that data available in cache before it is needed Guide to Operating Systems, Third Edition

13. Address Bus • Address bus • internal communications pathway It is instrumental in the transfer of data to and from computer memory • runs at the external clock speed of the CPU Guide to Operating Systems, Third Edition

14. Data Bus • Data bus • allows computer components to share information • number of bits indicates how many bits of data can be transferred from memory to the CPU, or vice versa, in one clock tick • external clock speed of 1 GHz will have 1 billion ticks per second to the external bus Guide to Operating Systems, Third Edition

15. Control Bus • The CPU is kept informed of the status of resources and devices connected to the computer • The most basic information is whether or not a particular resource is active and can be accessed • Memory read and write status is transported on this bus • Interrupt Requests (IRQs) are also transported on this bus Guide to Operating Systems, Third Edition

16. Control Bus (continued) • An IRQ • request to the processor for a current process, such as a read from a disk drive, to be interrupted by another process, such as a write into memory Guide to Operating Systems, Third Edition

17. CPU Scheduling • Determine which process to start given the multiple processes waiting to run • Allows for multithreading • Ability to run two or more processes at the same time Guide to Operating Systems, Third Edition

18. Popular PC Processors • These CPUs are: • Intel • Intel Itanium • AMD • Motorola • SPARC • Alpha Guide to Operating Systems, Third Edition

19. Intel • Most popular CPUs are designed by Intel • First in this line of processors was the 8088, the CPU found in the original IBM PC • Next Intel released the Multimedia Extension (MMX) • Pentium 4 is the presence of two math coprocessing units, called arithmetic logic units (ALUs) Guide to Operating Systems, Third Edition

20. Intel Itanium • The Intel Itanium processor is a significant departure from previous Intel processors in two aspects: • built on the RISC-based EPIC architecture and it is a 64-bit chip • intended for very large-scale operations that match powerful mainframes Guide to Operating Systems, Third Edition

21. AMD and Cyrix • Advanced Micro Devices, Inc. (AMD) and VIA Technologies (Cyrix) • compete with Intel Guide to Operating Systems, Third Edition

22. Motorola • Chips are typically found in Macintosh computers • Line of CISC CPUs is used in many older Macintosh computers, as well as in many UNIX computers Guide to Operating Systems, Third Edition

23. PowerPC • Developed jointly by IBM, Motorola, and Applet Computer • These are RISC chips known as the PowerPC line • Newest chip in the PowerPC line is the G5 (for 5th generation Guide to Operating Systems, Third Edition

24. SPARC • SPARC processor designed by Sun Microsystems • SPARC CPUs have gone through many incarnations • RISC processor is the most popular on the market today • The UltraSPARC III is the current version of the SPARC processor at this writing Guide to Operating Systems, Third Edition

25. Alpha • Originally designed by Digital Equipment Corporation (DEC) • Today, the Alpha CPU is found in high-end HP servers • 64-bit data bus and a 64-bit address bus • The internal clock speed can be as high as 1 GHz Guide to Operating Systems, Third Edition

26. Popular PC Operating Systems • Many operating systems available for today’s computers. • Following slides will briefly describe Guide to Operating Systems, Third Edition

27. MS-DOS and PC DOS • Microsoft’s original operating system • DOS is a 16-bit, single-tasking, single-user operating system Guide to Operating Systems, Third Edition

28. Windows 3.x • GUI interface to compete with the Apple Macintosh • Released in 1985 • Not well accepted until Windows 3.0 released • Windows 3.11 is also referred to as Windows for Workgroups (WFW • WFW is a peer-to-peer network operating system • each computer on a network can communicate with other computers on the same network Guide to Operating Systems, Third Edition

29. Windows 95 • True 32-bit operating system • Does not rely on MS-DOS to provide underlying functionality • Requires more CPU speed and memory Guide to Operating Systems, Third Edition

30. Windows 95 (continued) • More advanced functions: • A new GUI • Plug and Play • ActiveX and the Component Object Model (COM) capability • The Registry • Multitasking • Enhanced network capabilities Guide to Operating Systems, Third Edition

31. The Windows Desktop • Windows 95 introduces the GUI, now called the desktop, see Figure 2-3 • Backward compatibility to run old MS-DOS and Windows 3.x programs Guide to Operating Systems, Third Edition

32. Plug and Play • Plug and Play (PnP) • automatically detect newly installed hardware Guide to Operating Systems, Third Edition

33. ActiveX and the Component Object Model (COM) • ActiveX, along with its parent, the Component Object Model (COM) • standardized way for objects, such as programs, files, computers, printers, control panels, windows, and icons, to communicate with each other • The COM and ActiveX technologies enable an object to “sense” when it is interacting with other objects • Mouse, printer, desktop, trash can, or Start menu • The COM and ActiveX allow you to drag files from one place to another Guide to Operating Systems, Third Edition

34. The Registry • Database that stores information about hardware and software configurations • In Windows 95, the Registry is the only correct way to store configuration information Guide to Operating Systems, Third Edition

35. The Registry (continued) • The Registry is a hierarchical database that provides the following information: • Operating system configuration • Service and device driver information and configuration • Static tuning parameters • Software and application parameters • Hardware configuration • Performance information • Desktop configuration Guide to Operating Systems, Third Edition

36. Multitasking • Multitasking still performed on a cooperative basis for 16-bit applications, uses preemptive multitasking for 32-bit applications • Task supervisor • detects tasks that appear stuck Guide to Operating Systems, Third Edition

37. Enhanced Network and Internet Capabilities • The networking functionality was completely rewritten • Network drivers are part of the Windows operating system • Networking code is written as a 32-bit application • Integrated with the Internet • Extensive Internet support, in Web browsers, Web server software • Dial-Up Networking (DUN) • used to make connections to remote networks or computers Guide to Operating Systems, Third Edition

38. Windows 98/Me • Similar to Windows 95 • Many of the problems of Windows 95 are solved • Includes Registry checks and automatic Registry repair Guide to Operating Systems, Third Edition

39. Windows 98 • The backup mechanisms greatly enhanced • Changes from Windows 95 to Windows 98 are listed on page 66 • Universal Serial Bus (USB) • high-speed input/output port • Uses improved cooperative multitasking for 16-bit applications and preemptive multitasking for 32-bit applications Guide to Operating Systems, Third Edition

40. Windows 98 (continued) • ActiveX technology deployed as a standard feature in Windows 98Windows 98 can be updated over the Internet • Setting up dial-up connections and configuring the computer to use the Internet are simpler Guide to Operating Systems, Third Edition

41. Windows Millennium Edition (Me) • Windows Millennium Edition (Me) is the last in the 95/98 track • Windows Me was developed for home computer users • Infrared Data Association (IrDA) • support, and implements the enhanced PnP standard, called Universal Plug and Play (UPnP) • UPnP provides better discovery of new devices Guide to Operating Systems, Third Edition

42. Windows NT • Windows NT 3.1 was released in 1993 and version 3.5 was released in 1994 • Windows NT was an extension to IBM’s high-end operating system, OS/2 • intended to support a client/server networking environment • Windows NT has gone through many iterations • Windows NT prior to version 3.51 were not stable or reliable Guide to Operating Systems, Third Edition

43. Windows NT (continued) • Uses preemptive multitasking • Employs multithreading • ability to run two or more program code blocks as threads, at the same time • NT Workstation can use up to two CPUs • NT Server can use up to four CPUs • Symmetric multiprocessing (SMP) • All CPUs carry out actions at the same time Guide to Operating Systems, Third Edition

44. NT Server and NT Workstation • Windows NT Workstation is the operating system for a person who needs a high-end, stable, and secure graphical operating system • Windows NT Server is designed as a multi-user, server operating system for access over a network Guide to Operating Systems, Third Edition

45. NT Server and NT Workstation (continued) • The Registry plays an equally important role in Windows NT • Used as the central repository for configuration, hardware, software, and user information • Windows NT is designed as a multi-user system Guide to Operating Systems, Third Edition

46. Networking Support • Supports network connectivity protocols • IBM mainframes, UNIX computers, Macintosh computers, all Windows-based computers, Novell NetWare servers, etc Guide to Operating Systems, Third Edition

47. Security • A C2 rating means the Server network operating system provides security: • File and folder protection • User accounts and passwords • File, folder, and account auditing • File server access protection on a network • File server management controls Guide to Operating Systems, Third Edition

48. Security (continued) • The domain is an integral part • One primary domain controller (PDC) • The PDC is responsible for keeping usernames and passwords for all users • Remote Access Service (RAS) • user information in a PDC can be used to grant or deny various levels of network access Guide to Operating Systems, Third Edition

49. Windows 2000 • More robust operating system • Significant rewrite of the Windows NT kernel • Runs about 30% faster than Windows NT • More advanced networking support, such as Virtual Private Networks (VPNs) • A VPN is a private network that is like a tunnel through a larger network Guide to Operating Systems, Third Edition

50. Windows 2000 (continued) • Windows 2000 incorporates a wide range of new features, including: • Active Directory • Distributed network architecture • Kerberos security • IntelliMirror • Power Management • International Language Compatibility Guide to Operating Systems, Third Edition