The History of Virtual Machines - Essay Example

Virtual Machine Research Paper VIRTUAL MACHINE RESEARCH PAPER Virtual Machine Research Paper 2 VIRTUAL MACHINE RESEARCH PAPER In the late 1960s, when first conceptual thought was given by researchers at IBM till today's computing world, virtual machines has proven to be quite powerful and used to solve many computing problems, such as computer program portability, operating system design and others Virtual Machine A virtual machine is a program running on a computer that creates a self-contained operating environment between the computer platform and the end user and presents the appearance to the user of a different computer. A software program that emulates a hardware system. Virtual machine is a collection of software like JVM (java virtual m/c) that provides run time environment (e.g. data structure support) to user applications. Such software is now referred with the terms virtualization that is running two or more copies of the same operating system or two or more different operating systems and virtual servers. The host software, which provides this capability, is often referred to as a virtual machine monitor or hypervisor. It resides between the hardware and the "guest" operating systems. There are four major conceptual models of Virtual Machines used today and cater for different problem The IBM Model as demonstrated in the IBM S/390 solved the need for a single computer system that could simulate multiple computers with different operating systems. One of the best-known examples of an application virtual machine is Sun Microsystems's Java Virtual Machine. It is a software application that emulates a computer. It has it's own CPU Virtual Machine Research Paper 3 instruction set and maps JVM calls to operating system calls. It simulates a fake CPU that interprets the fake CPU instructions (what is usually referred to as byte code). The most significant feature of the Java Virtual Machine the ability write a program once and execute it with Java Virtual Machines on multiple platforms. The OSI Virtual Machine and the Unix Virtual Machine, represented by the Unix user shell are used to create operating systems and providing services and functions at the operating system level that did not exist in the system hardware. The OSI Virtual Machine model solved the problem of providing services and functions at the operating system level that did not exist in the system hardware. The Unix Virtual Machine model solved series of computer engineering problems by addressing the need for a modular approach to managing the launching and control of Unix processes. The success of the Unix operating systems is to a largely to the versatility and scalability of the Unix process. The History of Virtual Machines Around 1965 the researchers at IBM Yorktown Research center, developed first virtual machine environment, for the IBM System/360 mainframe called VM, which was entirely based in software. Later, IBM developed an implementation of its notion of a virtual machine and added hardware circuits to provide more robust and speedy partitioning between system images. This real world operating system, allows the user to share the resources available on their mainframe computers with many people, thus creating a multiple user environments. . This machine is now known as the IBM System 370 (S/370) and the IBM System 390 (S/390). These machines make use of the IBM VM/ESA operating system and are collectively referred to as IBM's VM lineage. Virtual Machine Research Paper 4 Benefits of running a virtual machine Virtual machine allow user to write applications on one OS and it can be executed on a machine which runs a different OS.One use is to provide multiple users the illusion of having an entire computer. Another advantage is that booting and restarting a virtual machine can be much faster than with a physical machine, since it may be possible to skip tasks such as hardware initialization. Virtual machine allows for testing OS's and requires less hardware. No need to get compatible drivers as all hardware is virtualized and no cross contamination. It allows user for legacy applications that require a special setup for operating system. User can use expensive hardware to its full potential and can run much number of servers on it. Virtual servers are easy to transfer from one server to another server. It is not restricted to hardware manufacturers (Sun, IBM, Apple etc). VMWare allows for zero downtime for virtual servers, even when the hardware needs to go offline - just move to different hardware 'on the fly'! Disadvantages of running a virtual machine The big disadvantage with virtual machines is that they are slow. It takes time for interpretation and then execution as opposed to an actual machine where only execution is required and seeing every machine's files is a big problem. Several popular Win/Mac programs that will not run reliably on Linux box. WIN doesn't network easily to Linux files. Challenges in running a virtual machine In testing environments, Virtual machine doesn't really give a good indication of hardware compatibilities due to virtual drivers. It needs expensive hardware to run on production systems Cost involved is high and there are different vendors, VMWare, Microsoft and others. It Virtual Machine Research Paper 5 ideally needs a multi-CPU system, OS support: MAC Server, Sun and others. In addition, virtual, multitasking, multi-user have their limit as concerns error. Creating these system demands the use of check such cyclic redundancy check because errors are increased in these circumstances. It must be error free. Licensing is gray in some areas. VMWare license, many MS licenses needed to operate it. Virtual machine proved to be a very powerful tool that is extending the abilities of modern computer systems and applications. List of Virtual Machine products and software The commercial markets today are flooded with many virtual machine support hardware and virtualization software products and are extensively used by Business entities and Universities and in IT sector. Some of the products and their features are listed below: Parallels Workstation is the first commercial software product released by Parallels, Inc. a developer of desktop and server virtualization software. The Workstation software consists of a virtual machine suite for Intel x86 compatible computers for running Microsoft Windows, Linux or Mac OS X. SVISTA (Serenity Virtual Station) promoted by Serenity Systems International and twoOStwo by Parallels Software Studio, consists of a virtual machine suite for Intel x86-compatible computers, which allows the creation and execution of multiple x86 virtual computers simultaneously. VMware Inc supplies much of the virtualization software available for x86-compatible computers, including VMware Workstation and the freeware VMware Server and VMware Player products. VMware software runs on Windows, Linux, and will soon debut on Mac OS X. Virtual Machine Research Paper 6 Xen is a free virtual machine monitor for x86, Intel Itanium and PowerPC architectures that enables the execution of multiple guest operating systems on the same computer hardware. Virtual PC is a virtualization suite for Microsoft Windows operating systems, and an emulation suite for Apple Mac OS X. Virtual PC emulates a standard PC and its associated hardware. Thus, it can be used to run nearly all operating systems available for the PC. MachTen is an Unix-like operating system from Tenon Intersystems that runs as an application program (in a virtual machine) on Apple Macintosh computers running Mac OS.MachTen is based on 4.4BSD and the Mach kernel, and features the X Window System and GNU programming tools. The Burroughs B1000 Series machines consisted of three major generations. These were the B1700, B1800, and B1900 series machines. The B1000 series could address a maximum of 2Mbytes of memory. In these days of multiple giga-bytes that sounds fairly limiting, but most commercial installations got by with 100s of Kbytes of storage HotSpot is the primary Java Virtual Machine for desktops and servers produced by Sun Microsystems. It features techniques such as just-in-time compilation and adaptive optimization designed to improve performance. The HotSpot Java Virtual Machine is written in C++ VM/CMS (Virtual Machine/Conversational Monitor System) is a bundled pair of operating systems used on IBM System/360, System/370, System/390, zSeries, and System z9 mainframes (and compatible systems). VM/CMS has two main components, VM and CMS, each an independent operating system. VM is a virtual machine operating system, which provides each user with what seems to be their own personal mainframe. CMS is a relatively simple single-user operating system, designed to run principally in a virtual machine. Reference Jain R, Kasturi R & Schunck BG (1995). Machine vision NY, USA: McGraw-Hill, P.724-750. Kohlbrenner Eric, Dana Morris Dana& Morris Brett (2000). The history of virtual machines. Retrieved October 10, 2006, from http://cs.gmu.edu/cne/itcore/virtualmachine/history.htm Lindholm T&YellinF (1999). Java Virtual Machine Specification, Inc. Boston, MA, USA Addison-Wesley Longman Publishing Co. Tech Encyclopedia. Virtual machine. Retrieved January 4, 2001, from http://www.techweb.com/encyclopedia/defineterm.jhtml Wikipedia. Virtual machine. Retrieved January 4, 2001, from http://en.wikipedia.org/wiki/Virtual_machine Read More