Introduction to Operating Systems Part I:Operating Systems Overview Part II: Operating Systems in Practice (focusing on Windows and Linux) PLEASE MAKE COPIES OF LINSPIRE LIVE-CD FOR LAB PRACTICE THIS WEEK
Early Computers • Charles Babbage (1791-1871) designed the first true digital computer called the analytical engine. • That was purely mechanical and intended to do math operations • The engine was supposed to be made of brass, and steam powered • He did not actually built the machine but inspired others in the field.
Early Computers • Babbage also thought of the concept of software • And hired the first programmer (Lady Ada, Countess of Lovelace) for his analytical machine
Current Computer Systems • A computer system consists of • hardware • system programs • application programs
What is an Operating System • It is the software that enables us to use the hardware • It is a resource manager • Allocates system resources such as I/O devices, CPU etc • Schedules different jobs etc
History of Operating Systems • First generation 1945 - 1955 • vacuum tubes, plug boards • Still very slow and used for scientific calculations • No OS was needed • Programs were entered by setting some switches
IBM STRETCH DEC PDP-1 History of Operating Systems • Second generation 1955 – 1965 • transistors, batch systems • Universities started to buy computers (spending millions of dollars) • Punched cards were used • To run a job (a program or a set of related programs) first punch it and give the deck to the operators and wait for the output (batch operation) • Computers were single user
History of Operating Systems • Third generation 1965 – 1980 • Integrated Circuits • Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip • "But what ... is it good for?"
Famous Remarks • "I have traveled the length and breadth of this country and talked with the best people, and I can assure you that data processing is a fad that won't last out the year.“ • The editor in charge of business books for Prentice Hall - 1957
History of Operating Systems • Multiprogramming system • three jobs in memory – 3rd generation
History of Operating Systems The concept of spooling was introduced by 3rd generation operating systemsand a memory partition was available, it is loaded directly to memory. Third generation OSs were still not interactive, i.e., whenever there is an error, programmers would realize it after a couple of hours. This problem lead to timesharing systems where the user has an online terminal
History of Operating Systems • Tanenbaum wrote a version of UNIX called MINIX with POSIX support for educational use. • A Finnish student Linus Torvalds wrote a free production of MINIX called Linux
History of Operating Systems • Fourth generation 1980 – present • Personal computers were developed after LSI (Large Scale Integration) circuits were invented. • First Microcomputer: • Intel 8080 CPU + attached 8-inch floppy disk • First disk based OS CP/M (Control Program for Microcomputers) • In 1980s IBM designed the IBM PC and contacted Bill Gates for an operating System
Brief History of Operating Systems Development Recent Developments Distributed computing, personal computers, high-speed communication, multi-media Second Generation Job scheduling, JCL, faster I/O, spooling, batch, files 1940 1955 1965 1980 1990 First Generation Vacuum tube, single user, early operating systems Third Generation Shared processing, multiprogramming, virtual memory, DBMS Understanding Operating Systems
Famous Remark • “There is no reason anyone would want a computer in their home.“ • Ken Olson, president, chairman and founder of Digital Equipment Corp. - 1977
History of Operating Systems • Bill Gates suggested IBM that they should look at CP/M (one of the the most successful OS for microcomputers at that time, by Gary Kildall) • The biggest mistake of all: • Kindall refused to sign a non-disclosure agreement • IBM went back to Bill Gates and signed a contract with him to write an OS for their new home computer • MS-DOS was based on QDOS, the "Quick and Dirty Operating System" written by Tim Paterson of Seattle Computer Products, • QDOS was based on Gary Kildall's CP/M • Microsoft bought the rights to QDOS for $50,000
Famous Remark • "I think there is a world market for maybe five computers." • Thomas Watson, chairman of IBM - 1943
History of Operating Systems • Early MS-DOS was very primitive but later versions included advanced features taken from UNIX • The early OS for microcomputers were based on users typing in commands from the keyboard • Doug Engelbart from SRI invented the Graphical User Interface (GUI) with windows, icons, menus, and mouse.
History of Operating Systems • Steve Jobs saw the value of GUI in a PC and developed the Apple computer with GUI (Apple Macintosh) in his garage. • He is also the co-founder of Pixar which has created very successful animated films: Toy Story ; A Bug's Life; Toy Story 2; Finding Nemo; Monsters.
Yet another Famous Remarks! • "640K ought to be enough for anybody." • Bill Gates, 1981
History of Operating Systems • Microsoft developed a GUI-based system called Windows which originally ran on top of MS-DOS (just as a GUI to DOS) • Windows 95 and 98 were real GUI based operating systems still based on 16 bit Intel assembly language • Windows NT is 32-bit rewrite from scratch version of Windows 98. • Windows 2000 (Windows NT version 5.0), Windows Me.
History of Computinghttp://www.computerhistory.org/ • Hewlett Packard was founded in 1939 by David Packard and Bill Hewlett, • Their first product, the HP 200A Audio Oscillator • Walt Disney Pictures ordered eight of the 200B model to use during the creation of the movie “Fantasia.”
History of Computinghttp://www.computerhistory.org/ Computer wars: Germany vs Britain Alan Turing: The bombe
Overview of Operating Systems • Introduction • Operating System Components • Machine Hardware • Types of Operating Systems • Brief Introduction of OS Development – focusing on Linux (because we’re already familiar with Windows • Linux vs Windows • The implications of of Linux in education Understanding Operating Systems
Components of an Operating System Operating system – part of the computing system that manages all of the hardware and all of the software • Controls every file, device, section of main memory & every nanosecond of processing time • Memory manager • Processor manager • Device manager • File manager Operating system consists of
Tasks Performed by Each Subsystem • Monitor its resources continuously • Enforce the policies that determine who gets what, when and how much • Allocate the resource when appropriate • Deallocate the resource (reclaim it) when appropriate
Machine Hardware • Memory chips • Input/output devices (monitor, keyboard, printer) • Storage devices (disks, magnetic tape, card readers, drums) • Central Processing Unit (Arithmetic Logic Unit, registers, internal control, bus control)
Windows Vista • Win release after XP (Oct 01 2006) • Desktop only release • Originally 2004, now 2006 • WinFS (NTFS add-on) OUT • Avalon 3D GUI layer, XML-based • Based on .NET APIs WinFX • Digital Rights Restrictions
MacOS X (Refer to Introduction to MAC OS downloadable from http//:zaipul.wikispaces.com)
What we will cover • Why Linux? • What is Linux? • Myths of Linux • Example GUIs & app's • Summary
Origins of Linux • Began as student Project by Linus Torvalds Opened up to the world, now backed by big business • Scientific cooperation model • Open source implications Better security, anyone can improve, open to all, improved competition, cheaper, faster • Matured over 14 years WinXP (3-12 years), Solaris 2 (15yrs), MAC OS (26 years)
Linux kernel • Linus Torvalds in 1991 • Based on Minix kernel • Linux kernel works with GNU components • Allow commercial redistribution (GPLv2)
GNU Project (GNU’s Not Unix) • Linux truly began from the inspiration of a brilliant man Richard Stallman in 1983. • To develop Unix-like OS composed entirely of free software (GNU GPLv1)
What is Linux ? • UNIX-like operating system • Comprised • System utilities • Libraries From GNU Project Sometimes called GNU Linux • Supported by: IBM, Sun, Novell, Microsoft,…
What is Linux? Kernel + cmds/libs + apps + installer = a DISTRO
Well-known distros • Slackware • Debian • Redhat, Fedora • SuSE (drived from Slackware) • Ubuntu (drived from Debian) • Knoppix • Linspire (drived from Debian)
Distros • Business • Embedded • Webserver • Home Desktop!
Why Choose Linux? • Stability . Since Linux is based on the stable UNIX operating system, it inherits that stability and reliability. Our Linux servers have uptimes in the MONTHS. • Linux is open-source, which means the source code is readily available to anyone who wants it. Since the source code available, thousands of developers all over the world are able to contribute and improve Linux. As a result, security patches and new drivers come out quickly, sometimes in less than a day. This insures a very stable operating system and high uptime for your network operations. • Affordability . You can download Linux software for free from the Internet at Real Time Enterprises´ local mirror or CDs can be purchased from distribution vendors for as little as $40. • Linux can run on PC-based hardware. This means it´s easy to add disk space or memory. AND, some services will run very well on a P1 with 64MB RAM, which you probably have collecting dust at your office. • Speed . Many studies have proven that on equal hardware, Linux is several times faster than Windows NT. In our own experience a Linux fileserver running Samba was at least 10 times faster than a Windows NT server and the NT server had faster, better hardware! • Linux uses a graphical user interfacethat is similar toother proprietary operating systems. (example: Microsoft XP or Mac OSX)
Growth to today • 1996 KDE desktop environment • 1997 GNOME • 1998 Netscape source code, Mozilla Firefox • 2000 StarOffice by Sun, then OpenOffice.org
And now and future • 25% server, 2.8% desktop (IDC, 2004) • Expected $38 billion in 2008
Philosophy of Linux • Free software and open source • Freedom to use without restrictions • Freedom to study software and its source code • Freedom to modifyo redistribute under certain conditions • Interoperability (with other OSs) • Portability (on various architectures) • Community • Commercialization
Linux distributions (distro) • To collect separate softwares, including: • Boot loader • Linux kernel • GNU libraries and tools • Command-line shells • Graphical X Window System • Desktop environment • Application software packages
Sweet Spot Linux Use • Supercomputer clusters • Web servers • Firewalls, routers, caches • File servers • Mail servers • PDA, cell phones • Embedded real time (gas pumps, Tivo etc)
Linux Myths • Zero cost • Difficult to learn • Only for servers • Less secure than Windows • Invulnerably secure • Always suitable
Myths debunked • Without cost A few distros free, most are commercial. Support is important • Difficult to learn Linspire is easy for anyone to learn & use • Only for servers Linspire well-proven on laptops, desktops • Less secure than Windows Linux has secure alternatives to IE, Outlook, and the registry – 3 of the buggiest virus propagators around. Still should follow good security practices • Always suitable Works very well for surfing/email/Word
Requirements for a Desktop Linux • Compatible with your data • Popular applications • Secure • Easy to use • Plays all media • Paid support • Reasonably priced • Easy to install