Guide to Operating Systems, 5th Edition PDF

Guide to Operating Systems, 5th Edition Unit 1 Operating Systems Fundamentals Objectives Overview © Cengage Learning 2017  Operating Systems An operating system (OS) is a set of programs containing instructions that work together to...

Guide to Operating Systems, 5th Edition Unit 1 Operating Systems Fundamentals Objectives Overview © Cengage Learning 2017  Operating Systems An operating system (OS) is a set of programs containing instructions that work together to coordinate all the activities among computer hardware resources An Operating System (OS) is an interface between a computer user and computer hardware. Some popular Operating Systems include Linux, Windows, OS X, VMS, OS/400, AIX, z/OS, etc. © Cengage Learning 2017  What is an Operating System?  An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drives and printers. © Cengage Learning 2017 4  Four Components of a Computer System 11/11/24 © Cengage Learning 2017 5  Following are a few common services provided by an operating system Program execution I/O operations File System manipulation Communication Error Detection Resource Allocation Protection Read More https://www.tutorialspoint.com/operating_system/ os_services.htm 11/11/24 © Cengage Learning 2017 6  Operating System Functions The process of starting or restarting a computer is called booting © Cengage Learning 2017  Operating System Functions: Booting Your Computer Booting is a startup sequence that starts the operating system of a computer when it is turned on. A boot sequence is the initial set of operations that the computer performs when it is switched on. Every computer has a boot sequence. The boot sequence is important to know for customizing and troubleshooting your computer. Boot Loader – The program that starts the “chain reaction” which ends with the entire operating system being loaded is known as the boot loader (or bootstrap loader). Boot Devices – The boot device is the device from which the operating system is loaded. A modern PC BIOS (Basic Input/Output System) supports booting from various devices. These include the local hard disk drive, optical drive(CD), floppy drive, a network interface card, and a USB device. © Cengage Learning 2017 8  Operating System Functions An operating system includes various shut down options © Cengage Learning 2017  Operating System Functions A user interface controls how you enter data and instructions and how information is displayed on the screen With a graphical user interface (GUI), you interact with menus and visual images © Cengage Learning 2017  Operating System Functions With a command-line interface, a user uses the keyboard to enter data and instructions © Cengage Learning 2017  Operating System Functions How an operating system handles programs directly affects your productivity © Cengage Learning 2017  Operating System Functions The operating system determines the order in which tasks are processed © Cengage Learning 2017  Operating System Functions Operating systems typically provide a means to establish Internet connections © Cengage Learning 2017  Operating System Functions A performance monitor is a program that assesses and reports information about various computer resources and devices © Cengage Learning 2017  Operating System Functions Operating systems often provide users with the capability of: © Cengage Learning 2017  Operating System Functions Automatic update automatically provides updates to the program © Cengage Learning 2017  Operating System Functions Some operating A network systems are designed administrator uses the to work with a server server operating on a network system to: A server operating – Add and remove system organizes users, computers, and other devices and coordinates how – Install software and multiple users access administer network and share resources security on a network © Cengage Learning 2017  Operating System Functions Each user has a user account – A user name, or user ID, identifies a specific user – A password is a private combination of characters associated with the user name © Cengage Learning 2017  Operating System Functions Operating systems typically provide a means to establish Internet connections © Cengage Learning 2017  Operating System Functions A performance monitor is a program that assesses and reports information about various computer resources and devices © Cengage Learning 2017  Operating System Functions Operating systems often provide users with the capability of: © Cengage Learning 2017 Types of Operating Systems © Cengage Learning 2017  Stand-Alone Operating Systems A stand-alone operating system is a complete operating system that works on a desktop computer, notebook computer, or mobile computing device © Cengage Learning 2017  Stand-Alone Operating Systems Windows 7 is Microsoft’s fastest, most efficient operating system to date and is available in multiple editions: © Cengage Learning 2017  Stand-Alone Operating Systems Windows 7 provides programs such as: © Cengage Learning 2017 Stand-Alone Operating Systems © Cengage Learning 2017 Stand-Alone Operating Systems © Cengage Learning 2017  Stand-Alone Operating Systems The Macintosh operating system has set the standard for operating system ease of use Latest version is Mac OS X © Cengage Learning 2017 Stand-Alone Operating Systems © Cengage Learning 2017  Utility Programs A file manager is a utility that performs functions related to file management – Displaying a list of files – Organizing files in folders – Copying, renaming, deleting, moving, and sorting files and folders – Creating shortcuts © Cengage Learning 2017  Utility Programs A search utility is a program that attempts to locate a file on your computer based on criteria you specify © Cengage Learning 2017  Utility Programs An image viewer allows users to display, copy, and print the contents of a graphics file An uninstaller removes a program, as well as any associated entries in the system files © Cengage Learning 2017  Utility Programs A disk cleanup utility searches for and removes unnecessary files – Downloaded program files – Temporary Internet files – Deleted files – Unused program files © Cengage Learning 2017  Desktop Versus Server Operating System The server hardware can also take different forms: Traditional server – often used by small or medium businesses Rack-mounted server – CPU boxes mounted in racks that can hold multiple servers – All servers often share one monitor & pointing device Blade servers – looks like a card that fits into a blade enclosure – A blade enclosure is a large box with slots for blade servers – Medium and large organizations use blade servers © Cengage Learning 2017  Servers A server controls access to the hardware, software, and other resources on a network – Provides a centralized storage area for programs, data, and information © Cengage Learning 2017  Mainframes A mainframe is a large, expensive, powerful computer that can handle hundreds or thousands of connected users simultaneously © Cengage Learning 2017  Supercomputers A supercomputer is the fastest, most powerful computer – Fastest supercomputers are capable of processing more than one quadrillion instructions in a single second © Cengage Learning 2017  The Role of Application Software Application software – Any program a user might choose to run on a computer Examples: word processor, spreadsheet, database, and a computer game An operating system manages the communication among the applications, the user, and the computer – Allows application programmers to concentrate on applications that will run on any hardware, as long as the OS can control them © Cengage Learning 2017  The Role of Application Software Application programs communicate with hardware through the operating system © Cengage Learning 2017  The Role of the BIOS BIOS – basic input/output system A low-level program code that: – Resides on a chip on the computer’s motherboard – Initiates/enables communications with hardware devices – Performs tests at startup called power-on self test (POST) – Conducts basic hardware and software communications inside the computer – Starts a full-fledged operating system that interfaces with the user © Cengage Learning 2017  The Role of the BIOS Every PC has a BIOS, which is stored in a flash memory chip – Flash memory does not lose its contents when the computer is turned off BIOS is stored in a complementary metal oxide semiconductor (CMOS) memory chip When a PC is turned on: – Runs a startup program inside the BIOS – Program initializes the screen and keyboard, tests hardware, initializes the hard disk and other drives – Loads the main operating system onto the hard disk © Cengage Learning 2017 Multiuser Systems Cloud computing © Cengage Learning 2017  Single Tasking Versus Multitasking Earlier versions of OSs allowed programs to directly access hardware – More prone to unexpected hangs, system instability, or crashes Today’s OSs manage access to hardware – Major reason for this was to facilitate multitasking (running two or more programs at the same time) Two general types of multitasking: – Cooperative multitasking – Preemptive multitasking © Cengage Learning 2017  Single Tasking Versus Multitasking Cooperative multitasking – the OS hands over control to a program and then waits for the program to hand control back to OS – If program does not give control back to OS, it may hog the CPU until its operations are complete – No other program can run until control is given back to OS – Found in early Windows versions – Example: If you print a word-processing file and try to play Solitaire, you cannot play a card until the print job is finished © Cengage Learning 2017 Single Tasking Versus Multitasking Preemptive multitasking basics © Cengage Learning 2017  Single Tasking Versus Multitasking Single-tasking operating systems – execute one program at a time – To do something else, one program must be stopped – Older OSs like MS-DOS were single-tasking Single-tasking operating systems © Cengage Learning 2017 Single-User Versus Multiuser Operating Systems Comparing single-user and multiuser operating systems © Cengage Learning 2017 Summary © Cengage Learning 2017