The Designing Of Cloud Based Operating System

As technology advances, the processes that we use to manage that technology become more demanding, creating the need for new software and efficient processors. “The central processing unit or (CPU) is the heart of your computer and is used to run the operating system as well as all the programs.” (Chris Hoffman, CPU Basics: multiple CPU’s, cores and hyper threading explained.) With so much power in a single chip, we have created a powerful piece of technology that can be placed virtually anywhere.

The challenges for OS structures depend on the diversity of hardware like number of cores, memory hierarchy, IO configuration, instruction sets and interconnects.

The Important of Cloud Computing is increasing and it is receiving a growing attention in Scientific & Industrial Communities. Cloud computing is one of the top 10 most important technologies and has a greater possibility in successive years by companies and organizations. Cloud computing implement everywhere, favourable, on demand network access to a shared pool of configurable computing resources (e.g. networks, servers, storage, applications and servers) that can be immediately supply and released with minimal management effort.

There has always been an age-old debate over the advantages and disadvantages of a Reduced Instruction Set Computer(RISC) in contrast to its predecessor a Complex Instruction Set Computer(CISC). These processors differ vastly in structure, methods of execution and usability. RISC is a Central Processing Unit(CPU) design strategy that uses simpler, smaller instruction sets resulting in faster performance speeds. It has an assembly language that is designed so that each task is broken down into very simple instructions that are each executed once per clock cycle. In comparison CISC is a CPU design strategy based on single instructions, which are capable of performing multi-step operations but unfortunately has a slower clock speed. The majority

Abstract – Cloud computing is a type of computing that relies on sharing a pool of physical and/or virtual resources (e.g., networks, servers, storage, applications and services), rather than deploying local or personal hardware and software. This technology is mainly service oriented and focuses on cost reduction, hardware reduction and pay just for service concept. Virtualization in cloud computing is making a virtual image of the storage devices servers or network resources so that they can be used on multiple machines at the same time.

Modern processors commonly have several individual CPUs—called cores— built onto one die. Operating systems recognize each core as its own separate CPU and yield a system performance boost when performing multiple tasks at the same time. The physics is the same as having multiple CPUs in your system.

It is difficult to resolve issues in cloud computing environment because of its varied nature. In order to make user effectively utilize the existing computational power a new kind of operating systems are needed. Therefore cloud based operating systems promise vision to meet user’s needs at any time. At the same time designing of cloud based operating systems present many challenges to the designer. The common issues include scalability, elasticity of demand, and faults.

Cloud computing is large group of remote servers which are networked for facilitating pervasive, expedient, on-demand network access to configurable and common computing resources such as CPU processing, network bandwidth, disk space that can be quickly facilitated and reclaimed with minimum central management. The underlying complexity of such a system is handled by an Operating System which is designed to support interoperability, scalability, security, user privacy, data management, fault tolerance. These operating systems need to work proficiently in the background to ensure that all the resources are available when needed and ensure acceptable performance and quality of service.

Embedded platforms were initially composed of separate discrete components. The processor was a separate component with just a memory bus interface, and all peripherals were attached to this bus. As integration levels increase, more and more logic is added to the processor die, creating families of application-specific service processors. The term system on chip (SOC) is often used to describe these highly integrated processors. These SOCs include much of the logic and interfaces that are required for a range of specific target applications. The silicon vendors that develop these SOC devices often create families of SOCs all using the same processor core, but with a wide range of integrated capabilities.

This “Case Study” cover information on computer systems with multicore processors which can increase performance by running applications of various types (models) and methods. This paper focuses on applications using distributed architecture, cache contention, prefetching hardware and more. Current and future contentions are discussed. Managing contention for shared resources on multicore processors are discussed in this assignment. Explanations given for causes of contention. Discussion of the

The shift to multicore Exascale systems will require applications to exploit million-way parallelism and overcome significant reductions in the bandwidth and volume of memory available to each CPU. There is another looming shift in the complexity of the node architectures that will be as big a challenge to software development as the exponential growth in processors. This is the potential shift to heterogeneous node architectures. The major challenges caused by the increasing scale and complexity HPC systems are cross cutting of the entire software stack. The software challenges include the rapid increase in parallelism, the memory wall, system heterogeneity and fault tolerance.

By implementing multi-core processors, we can dramatically increase a computer’s capabilities and computing resources, providing better responsiveness, improving multithreaded throughput, and delivering the advantages of parallel computing to properly thread mainstream applications (Ramanathan). When multi-core processing was just beginning there were already immediate benefits. One immediate benefit was that multi-core processors improved an operating system’s ability to multitask applications. For instance, say you have a virus scan running in the background while you’re working on your word-processing application (Ramanathan). Another major multi-core benefit comes from individual applications optimized for multi-core processors (Ramanathan). These applications, when properly programmed, can split a task into multiple smaller tasks and run them in separate threads

4. Performance Comparison of Dual Core Processors Using Multiprogrammed and Multithreaded Benchmarks ............................................................................................... 31 4.1 Overview ........................................................................................................... 31 4.2 Methodology ..................................................................................................... 31 Multiprogrammed Workload Measurements .................................................... 33 4.3 4.4 Multithreaded Program Behavior ..................................................................... 36 5. 6. Related Work ............................................................................................................ 39 Conclusion ................................................................................................................ 41

OS that does not support multithreading cannot use multiprocessors: A thread which is a flow of execution through a process code which has its own program counter, system and stack is a light weight process that provides a way to improve an application performance through parallelism. Two important characteristics of windows are its support for threads and for symmetric multiprocessing (SMP). Within a single process, windows support the use of multiple threads of execution. Simultaneously, multiple threads that are within the same process may execute on different processors. Without multithreading, one cannot divide the work load, thus parallelism that is making use of more than one CPU simultaneously is impossible. Thus, if the operating system doesn’t support multithreading it cannot utilize the multiple processors because it can’t distribute the processes among the processors. That’s the reason supporting multithreading is required for this process.

Most major Operating Systems support multi-core processors. Operating System perceives each core as separate processor. The operating system scheduler maps it 's threads and processes to different cores.