(1)Virtual Machines The fundamental idea behind a virtual machine is to remove the hardware of a single computer and make it a self-contained operating environment that behaves as it is a separate computer. Essentially, the virtual machine is software that executes an application and isolates it from the actual operating system and hardware. CPU scheduling and virtual-memory techniques are used so that an operating system can create the illusion that a process has its own processor with its own (virtual) memory. The virtual machine provides the ability to share the same hardware yet run several different operating systems concurrently, as shown in Figure 2-11. Figure 2-11: Virtual machine concept A major difficulty with the virtual machine involves disk systems. For instance, the physical machine has two disk drives but wants to support five virtual machines. The physical machine is unable to allocate a disk drive to each virtual machine because the virtual machine software itself will need substantial disk space to provide virtual memory and spooling. To solve this dilemma, virtual drives that are identical in all respects except for size are provided. The system implements each virtual disk by allocating as many tracks on the physical disks as the virtual disk needs. Implementation of the virtual machine is difficult. A lot of work is required to provide an exact duplicate of the underlying machine, which has both the user mode and kernel mode. The virtual machine software can run in kernel mode since it is the operating system, where the virtual machine itself can only execute in user mode. In a virtual machine implementation, there must be a virtual user mode and a virtual kernel mode, both of which run in a physical user... ... middle of paper ... ... c. Process attributes, Memory allocation, System information, Communication, Transfer status information d. Send/Receive attributes, System information, Memory allocation, Device attributes, Information transfer 6. Operating system design goals and requirements are divided into two groups. What are these two groups? a. Kernel mode b. User c. System d. Supervisor mode 7. What is a microkernel? a. Operating system b. System call c. Smaller kernel d. Process 8. What is considered a suitable language for today's operating systems? a. Fortran b. C c. Visual Basic d. C++ 9. What are some advantages for using a virtual machine when developing an operating-system? a. Testing b. Implementation c. Debugging d. Control 10. What program loads the kernel when starting a computer? a. Read-only memory (ROM) b. Bootstrap c. Firmware d. System patch
Virtualization is a technology that creates an abstract version of a complete operating environment including a processor, memory, storage, network links, and a display entirely in software. Because the resulting runtime environment is completely software based, the software produces what’s called a virtual computer or a virtual machine (M.O., 2012). To simplify, virtualization is the process of running multiple virtual machines on a single physical machine. The virtual machines share the resources of one physical computer, and each virtual machine is its own environment.
---. “Sharing the Software.” Digital Chameleon: The Rise of Computer Emulation. 13 Sep. 1999. Zophar’s Domain. 25 Oct. 2000.
In this case I recommend for two types of virtualization in case of Regional garden limited company....
Moreover, these individual goals should align with organizational goals and needs and should meet the individual needs such promotions, monetary awards, challenging work, and achievement.
A process is a running program, one of the more important things about creating the illusion of virtualization is the speed at which the operating systems will change from one service to another or from one operation to another. Time-sharing is essentially the sequential ordering of instructions, in such a way that it appears each process vying for CPU time is running.
Specific goals and objectives within division: here, list and discuss the specific goals and objectives of your own department or organizational segment.
This document describes the final project for the course COEN 283 – Operating System. The project is team oriented, main goal is to select a topic related the Operating System concepts that should be either theoretical, in which new algorithm is analysis and simulate, in which subsystem/driver of an OS is prototyped. Provide the simulation/implementation code and explain the detail design in this report. This project will provide opportunity for students to perform research on topic of interest of operating system.
A basic operating system mainly contains 4 management functions includes process management, memory management, file management and I/O and disk management. Process management and file management will be mainly discussed in this case study.
(9 marks) 2. Discuss any 3 factors affecting the choice of an operating systems. (9 marks) 3. Discuss the following types of operating systems. - Multi tasking - Multi processing - Multi user - Real time (12 marks) 1.
Thin Client or Server-based computing is a model in which applications are deployed, managed, supported and executed 100% on a server. It uses a multi-user operating system and a method for distributing the presentation of an application's interface to a client device. The server-based computing model employs three critical components. The first is a multi-user operating system that enables multiple concurrent users to log on and run applications in separate, protected sessions on a single server. The second is a highly efficient computing technology that separates the application's logic from its user interface, so only keystrokes, mouse clicks and screen updates travel the network. As a result, application performance is bandwidth-independent.
Because of the robust Linux programmer community, several “flavour’s” of Linux (known as “vendors”) are available, and each is specialized in a slightly different way. This robust operating system is being widely adopted by IT professionals in growing businesses because of its high quality, reliability, and price.
The virtual organization is a network of independent suppliers, customers, and even competitors, generally tied together by computer technology (Roger, 1991). They share skills, costs, and access to markets. It is tend to have flat structures in which information and decision making move horizontally (Judith R.G, 2002). Through the support of modern electronic system, it becomes possible to link people across formal organizational boundaries (Judith, 2002, quoted in S.G. Straus, S.P. Weisband, and J.M. Wilson, 1998).
Virtualization technologies provide isolation of operating systems from hardware. This separation enables hardware resource sharing. With virtualization, a system pretends to be two or more of the same system [23]. Most modern operating systems contain a simplified system of virtualization. Each running process is able to act as if it is the only thing running. The CPUs and memory are virtualized. If a process tries to consume all of the CPU, a modern operating system will pre-empt it and allow others their fair share. Similarly, a running process typically has its own virtual address space that the operating system maps to physical memory to give the process the illusion that it is the only user of RAM.
Paging is one of the memory-management schemes by which a computer can store and retrieve data from secondary storage for use in main memory. Paging is used for faster access to data. The paging memory-management scheme works by having the operating system retrieve data from the secondary storage in same-size blocks called pages. Paging writes data to secondary storage from main memory and also reads data from secondary storage to bring into main memory. The main advantage of paging over memory segmentation is that is allows the physical address space of a process to be noncontiguous. Before paging was implemented, systems had to fit whole programs into storage, contiguously, which would cause various storage problems and fragmentation inside the operating system (Belzer, Holzman, & Kent, 1981). Paging is a very important part of virtual memory impl...
The input and output sections allow the computer to receive and send data, respectively. Different hardware architectures are required because of the specialized needs of systems and users. One user may need a system to display graphics extremely fast, while another system may have to be optimized for searching a database or conserving battery power in a laptop computer. In addition to the hardware design, the architects must consider what software programs will operate the system.