Operating Systems and Utilities - Essay Example

Operating Systems And Utilities How the Evolution of Operating Systems affect their suitability For Specific Tasks Academia Research Writer Farzeela Operating System An operating system is a program that manages the computer hardware by providing a basis of application programs and acts as an intermediary between the user and the computer hardware. Evolution of Microprocessor Operating Systems 8086 Processor (16 Bits) The first PC's were 16-bit machines, which could only work with the text with the only ability to manage one program at a time. That means these machines were single user with single tasking operations. 8088 Processor (16 Bits) Just after 8086, 8088 was introduced. The uniqueness of these processors was that the bus between the CPU and RAM of these processors was of 8 bits. 8088 machines possessed 256 KB, 512 KB or 1 MB of RAM. 8088 was much cheaper than 8086. 80286 Processor (16 Bits) Intel 80286 was one of the fastest PC's of 1984. Also called 286 was much efficient and possessed the following qualities: It simply performed much more work per clock tick than the 8086/8088. A new feature was also the 32-bit address mode (protected mode). It had access to all system memory - even beyond the 1MB limit, which applied to real mode. It performed multitasking (running of more than one programs at a time). The possibility of virtual memory, which means that the hard disk can be used to emulate extra RAM, when necessary, via a swap file. 32 bit access to RAM and 32 bit drivers for I/O devices. 80386 Processor (32 Bits) The Intel 80386 was the first 32-bit CPU. The 386 have 32-bit long registers and a 32-bit data bus, both internally and externally. The 80386 SX became the most popular chip with a discount edition of the 386 DX. The SX had a 16-bit external data bus, and that made it possible to build cheap PC's. 80486 Processor (32 Bits) X 86 instructions was utmost implemented by 80486, due to which it executed faster, in a more RISC (Reduced Instruction Set Computing)1 like manner. The 486 was also the first CPU with built-in L1 cache. The 486 working was twice as efficient and fast as 386 and with the same clock frequency. 486 was a multi user and multitasking operating system, which worked under several other operating systems like DOS, Windows 3.11 and Windows 95. New editions were released with higher clock frequencies and double-clocked processors named 80486 DX2. (Michael Karbo) Pentium Processor (32 Bit) Intel Corporation's microprocessor released in 1993, was the first fifth generation CPU incorporating more than 3.1 million transistors, the 32-bit Pentium processor is a highly integrated semiconductor device that has an external bus width of 64 bits. The first release featured clock speeds of 60 and 66 megahertz (MHz) achieving a performance of over 100 Mips2. It is almost twice as fast as the Intel 486 DX2 Microprocessor. This performance is largely due to the Pentium Processors superscalar3 Architecture. Its dual execution pipeline implementation utilizes advanced design techniques that enable it to transparently execute multiple instructions per clock cycle. The Pentium Processors enhanced 64-bit data bus carries information between the processor and the memory subsystems at 528 MB per second at 66 MHz. Other features of the Pentium Processor include: Branch prediction Floating point unit 64 bit data bus Multiprocessing support Memory page size option Error detection and functional redundancy Overdrive processor upgradability and Performance monitoring. (Jonar C. Nader, 3rd edition) Pentium II Processor Released in 1997, this microprocessor incorporated 7.5 million transistors. This 64-bit processor was first released in clock speeds of 266 MHz and 300 MHz and 64 gigabytes of addressable memory and 64 terabytes of virtual memory. In order to make the production cheaper Intel chose to place the cache outside the actual Pentium II chip. The disadvantage of this system was that the L2 cache became markedly slower than it would have been if it was integrated into the CPU. The L2 cache typically ran at half the CPU's clock frequency. At some point, Intel decided to launch a discount edition of the Pentium II the Celeron processor. In the early versions, the L2 cache was simply scrapped from the module. That led to quite poor performance, but provided an opportunity for overclocking4. One of the problems of overclocking a Pentium II was that the cache chips couldn't keep up with the high speeds. Since these Celerons didn't have any L2 cache, they could be seriously overclocked. Intel later decided to integrate the L2 cache into the processor. That happened in new versions of the Celeron in 1998 and a new version of the Pentium III in 1999. The socket design was also changed so that the processors could be mounted directly on the motherboard. (Michael B. Karbo, PC Architecture) Pentium III Processor Pentium III another edition of Pentium II was built on the same architecture as Pentium II i.e., P6. Pentium IV Processor The Intel Pentium IV is a seventh-generation X86 architecture microprocessor and is their first all-new CPU design, called the NetBurst architecture, since the Pentium Pro of 1995. The original Pentium 4, codenamed "Willamette", ran at 1.4 and 1.5 GHz and was released in November 2000. Unlike the Pentium II, Pentium III, and various other Celerons, the architecture owed little to the Pentium Pro design, and was new from the ground up. The Pentium IV did not improve on the two key performance measures like integer processing speed or floating-point performance. Instead, it sacrificed per-cycle performance in order to gain very high clockspeeds. As is traditional with Intel's flagship chips, the Pentium IV also comes in a low-end Celeron version (often referred to as Celeron IV) and a high-end Xeon version intended for SMP5 configurations. The design goal of the Pentium IV was to easily scale to fast clock speeds because consumers were beginning to purchase computers based on GHz ratings. Intel used a deep instruction pipeline to implement this goal, which reduced the amount of real work that the Pentium IV could do per clock cycle compared to other CPUs like the Pentium III and Athlon. Intel abandoned development of the Pentium IV to focus on the cooler running Pentium M, which was repositioned for the desktop computer and small server markets. In retrospect, the Pentium III core was technologically superior to Pentium IV. Only the system bus of the Pentium IV is still used in current system designs. (Wikipedia, Pentium IV) Evolution of the Pentium IV introduced the Hyper-Threading Technology, which is used in order to exploit the powerful pipeline in the Pentium IV; it has been permitted to process two threads6 at the same time. A single Pentium IV logically function as if there physically were two processors in the pc. Timeline of Operating Systems (1960-2003) 1960s 1961 CTSS 1964 OS/360 1965 Multics OS/360 Table Operating System (TOS) 1966 DOS/360 (IBM) MS/8 1967 ACP (IBM) CP/CMS ITS WAITS 1969 TENEX UNIX 1970s 1970 DOS/BATCH11 1971 OS/8 1972 MFT MVT RDOS SVS VM/CMS 1973 Alto OS RSX-11D RT-11 VME 1974 MVS (MVS/XA) 1976 CP/M TOPS-20 1978 Apple DOS 3.1 (first Apple OS) Trip OS VMS Lisp Machine (CADR) 1979 Apple DOS 3.2 POS 1980s 1980 Apple DOS 3.3 OS-9 QDOS SOS XDE (Xerox Development Environment) Xenix 1981 MS-DOS 1982 SunOS (1.0) Ultrix 1983 Lisa OS Coherent ProDOS 1984 Macintosh OS (System 1.0) QNX UniCOS 1985 AmigaOS AtariTOS MIPS OS Microsoft Windows 1.0 1986 AIX GS-OS HP-UX 1987 Arthur IRIX Minix OS/2 Microsoft Windows 2.0 1988 A/UX (Apple Computer) LynxOS MVS/ESA OS/400 1989 NeXTSTEP (1.0) RISC OS SCO UNIX (Release 3) 1990s 1990 Amiga OS (2.0) BeOS (v1) OSF/1 1991 Linux 1992 386BSD 0.1 Amiga OS 2.1 Amiga OS 3.0 Solaris Windows 3.1 1993 Plan 9 from Bell Labs (First Edition) FreeBSD NetBSD Slackware Linux Windows NT 3.1 (First version of NT) 1994 Amiga OS 3.1 Red Hat Linux 1995 Digital Unix Open BSD OS/390 Windows 95 1996 Debian GNU/Linux (Debian 1.1) Windows NT 4.0 1997 Inferno Mac OS 7.6 (first officially named OS) SkyOS 1998 MandrakeLinux Windows 98 1999 Amiga OS 3.5 AROS Mac OS 8 Windows 98 Second Edition 2000s Amiga OS 3.9 AtheOS Mac OS 9 MorphOS Visopsys Windows 2000 Windows Me (Millenium Edition) 2001 Amiga OS 4.0 Mac OS X Windows XP Z/OS 2002 Mona Syllable Red Hat Enterprise Linux 2003 Gentoo Linux Windows Server 2003 Fedora Core Linux FCI Example Systems MS-DOS (Single-user Operating System until Ver 3.1) MS DOS was developed by Microsoft for the first IBM personal computer in 1981. It was written in a great hurry, and borrowed lots of features from the then dominant PC operating system CP/M. DOS 1.0 consisted of 4000 lines of assembly language, and ran in 8k of memory on the Intel 8086 microprocessor. DOS 2.0, released in 1983 added support for hard disks (the PC XT), and several Unix-like features including hierarchical directories, and I/O redirection. It grew to have a 24kbyte memory resident. DOS 3.0 was introduced to run on the PC AT in 1984. Although the PC-AT incorporated the 80286 processor, which supports extended addressing and memory-protection, DOS did not use these features. The memory resident portion had grown to 36KB. DOS 3.1 (1984) had support for networking PCs. DOS 3.3 (1987) provided support for the IBM PS/2 family, some of which incorporated the 32 bit 80386 processor. Hardware improvements especially the introduction of 80486 and Pentium processors resulted in PCs capable of running multi-user, multitasking operating systems with support for virtual memory. DOS, however, used none of these features. Microsoft Windows (version 3 was launched in 1990) was interposed between the user and DOS, but the PC's functionality remained greatly restricted by the limitations of the underlying DOS. IBM and Microsoft attempted to address this by jointly developing a completely new single-user, multi-tasking, multithreaded operating system OS/2. IBM and Microsoft fell out in a major way during this development. IBM went on to develop OS/2 itself, whilst Microsoft developed two new operating systems, one for desktop clients (which was launched as Windows 95), and a second for servers and powerful workstations (Windows NT). Windows NT (Single-user Operating System that provides multitasking and multithreading) Like OS/2, Windows NT is a single-user operating system that provides multitasking and multithreading. Although the computer is being used by a single person, it provides the necessary functionality so that the user can run lots of programs simultaneously, cutting and pasting between them, and also provides network services like sharing files, and serving web pages. Windows NT has become quite widely used since the launch of NT 4.0 in the second half of 1996. NT operating system supports the graphical user interface of its Microsoft predecessors, and UNIX variants, especially the Mach operating system. Because NT is a new operating system, it has been able to incorporate many new ideas about modular structure and object orientated design. Its structure involves: Hardware, Hardware abstraction layer (HAL) allowing NT to run easily on multiple processor architectures, including Intel Pentium, DEC alpha, MIPS, and power PC, and also on multiprocessor architectures. The NT executive, which runs in privileged mode incorporating the kernel that manages scheduling, context switching, exception and interrupt handling and multiprocessor synchronization, the virtual memory manager, the I/O manager and the process manager. Protected sub-systems that enable NT to run application software written for other operating systems, including OS/2, Windows 32, and POSIX. These work through a client-server model running within NT and application software. UNIX (multi-user, multitasking, multithreaded and support symmetric multiprocessing) The origins of Unix are about as different from NT as can be imagined. Unix was developed in 1970 by a small number of engineers at the AT&T Bell labs who had been working on the Multics operating system project, which they considered to be failing. These individuals, including Ken Thompson and Dennis Richie, managed to get their hands on a "spare" DEC PDP 7 mini-computer, and implemented an operating system that some suspect was designed principally for playing computer games. Multics was a mainframe operating system originally planned for a "computer utility". A central computing utility company would buy a huge mainframe running multics, and sell time on it rather like an electricity utility sells electricity to its customers. This never happened, though Multics ended up running on a small number of Honeywell mainframes, up until the late 1980s. Unix has shell architecture, which is rather less modular than Windows NT. Hardware Kernel Process control (scheduler, memory management, interprocess communication) Device drivers File system Shell editors and private user programs Application programs Unix is portable because it is written in the C programming language and can be compiled to run on any computer for which a C compiler is available - from PCs with 80386 processors to massively parallel supercomputers. (Derek Hill, Operating Systems) References Derek Hill, Operating Systems accessed from < http://www-ipg.umds.ac.uk/d.hill/> Jonar C.Nader, Dictionary of Computing, Third Edition Michael B.Karbo, Operating Systems accessed from Read More