��化��成本之多少

��化��成本之多少

文/�其� (iThome���副���) 2008-07-28

微�的Hyper-V有多便宜呢？��Hypervisor技�目前��有分��，搭配著Windows Server 2008一起�就只要1千元。微�特�推出了Windows Server 2008 with Hyper-V的版本，�格只比未含��化技�的版本多1千元。

伺服器��化能�省整�成本，一直是企�最��注的��。在本期封面故事中，我�深入剖析��化的整�成本。 以100�伺服器的建置成本�分析，�100�全部都�用��伺服器的�，包含所有基本的硬�、��、管理人力的�用，最起�要1,970�元， 若��100�伺服器改�成��伺服器，在以20���伺服器整�100���伺服器的情�下，整�成本是1,329�元，比起全部用��伺服器�建置是 便宜了�百�元；再�一步提升�以10���伺服器整��100���伺服器，�整�成本大幅降至1千�元以下，我�估算出�的成本是832�元，比起全 部都用��伺服器，大幅�省1千�元。 上述是以目前主流的��化���估算，但�著微�近�祭出新一波��化策略，市�的����可能�有所��，伺服器��化的成本效益也��有所改�。 在x86伺服器���域，一�到��化，�大多�人都�想到VMware，因��家公司率先在市�上推�x86伺服器��化技�，藉由在技�研� �市�耕耘的�先��，多年下�在市�中都是一枝�秀，近年�甚至�占了全球超�8成以上的x86��化市�，使得VMware�乎就等同於是��化的代 名�了。 但是，好景不常，微�在今年下半年要端出重量�的�品，角逐企��的伺服器��化市�，而不�VMware�美於前。 微�之前就已�有��化��，像是Virtual Server及Virtual PC，不�，�些都是�用全��化（Full Virtualization）技�的�品，在技��面上比不上VMware及XenSource近��展的半��化技�（Para -virtualization）。 半��化是�用「���（Hypervisor）」技�，效能�比全��化技��得好，所以企�真正要把�用程式放到��伺服器的�，�乎都是�用半��化技�的�品，因而微�一直不在��化技�的主流��上。 但是，微��回�於端出了半��化的�品－Hyper-V，得以在主流��中�VMware一�高下。微��XenSource取得了半��化技 �，�把��技�整合在新一代伺服器作�系�Windows Server 2008。微�不�使出一�的作�系�捆��用程式的作法，�回�祭出了低�策略，直接��VMware的��策略。 微�的Hyper-V有多便宜呢？��Hypervisor技�目前��有分��，搭配著Windows Server 2008一起�就只要1千元。微�特�推出了Windows Server 2008 with Hyper-V的版本，�格只比未含��化技�的版本多1千元。���作�系�整合，�且只加�1千元的策略，�於其他��化���商���大的��力。 不�，�只是�����的�格，整套伺服器��化��的授��不只如此，�必�要把一些必�的管理��及作�系�授��也一�算��。 ��化��的整�授��用到底有多少？企�在�估�入��化之前一定要掌握�些��，在本期封面故事中，我��底剖析微�、VMware及XenSource的��授��，�且分析��化�商接下�在管理工具方面的布局，以及��世曦工程�����大�部署��伺服器的����。 http://www.ithome.com.tw/itadm/article.php?c=50037 虚拟化 来自ITwiki，开放的信息技术大百科 Jump to: navigation, <jumptoSearch> 虚拟化是指计算元件在虚拟的基础上而不是真实的基础上运行。虚拟化技术可以扩大硬件的容量，简化软件的重新配置过程。CPU的虚拟化技术可以单CPU模拟多CPU并行，允许一个平台同时运行多个操作系统，并且应用程序都可以在相互独立的空间内运行而互不影响，从而显著提高计算机的工作效率。 虚拟化技术与多任务以及超线程技术是 完全不同的。多任务是指在一个操作系统中多个程序同时并行运行，而在虚拟化技术中，则可以同时运行多个操作系统，而且每一个操作系统中都有多个程序运行， 每一个操作系统都运行在一个虚拟的CPU或者是虚拟主机上；而超线程技术只是单CPU模拟双CPU来平衡程序运行性能，这两个模拟出来的CPU是不能分离 的，只能协同工作。 虚拟化技术也与目前VMware Workstation等同样能达到虚拟效果的软件不同，是一个巨大的技术进步，具体表现在减少软件虚拟机相关开销和支持更广泛的操作系统方面。 [编辑] 软件方案 纯软件虚拟化解决方案存在很多限制。"客户"操作系统很多情况下是通过虚拟机监视器（Virtual Machine Monitor，VMM）来与硬件进行通信，由VMM来决定其对系统上所有虚拟机的访问。(注意，大多数处理器和内存访问独立于VMM，只在发生特定事件 时才会涉及VMM，如页面错误。)在纯软件虚拟化解决方案中，VMM在软件套件中的位置是传统意义上操作系统所处的位置，而操作系统的位置是传统意义上应 用程序所处的位置。这一额外的通信层需要进行二进制转换，以通过提供到物理资源(如处理器、内存、存储、显卡和网卡等)的接口，模拟硬件环境。这种转换必然会增加系统的复杂性。此外，客户操作系统的支持受到虚拟机环境的能力限制，这会阻碍特定技术的部署，如64位客户操作系统。在纯软件解决方案中，软件堆栈增加的复杂性意味着，这些环境难于管理，因而会加大确保系统可靠性和安全性的困难。 [编辑] 硬件方案 而CPU的虚拟化技术是一种硬件方案，支持虚拟技术的CPU带有特别优化过的指令集来控制虚拟过程，通过这些指令集，VMM会很容易提高性能，相比 软件的虚拟实现方式会很大程度上提高性能。虚拟化技术可提供基于芯片的功能，借助兼容VMM软件能够改进纯软件解决方案。由于虚拟化硬件可提供全新的架 构，支持操作系统直接在上面运行，从而无需进行二进制转换，减少了相关的性能开销，极大简化了VMM设计，进而使VMM能够按通用标准进行编写，性能更加 强大。另外，在纯软件VMM中，目前缺少对64位客户操作系统的支持，而随着64位处理器的不断普及，这一严重缺点也日益突出。而CPU的虚拟化技术除支 持广泛的传统操作系统之外，还支持64位客户操作系统。 虚拟化技术是一套解决方案。完整的情况需要CPU、主板芯片组、BIOS和软件的支持，例如VMM软件或者某些操作系统本身。即使只是CPU支持虚拟化技术，在配合VMM的软件情况下，也会比完全不支持虚拟化技术的系统有更好的性能。 两大CPU巨头Intel和AMD都 想方设法在虚拟化领域中占得先机，但是AMD的虚拟化技术在时间上要比Intel落后几个月。Intel自2005年末开始便在其处理器产品线中推广应用 Intel Virtualization Technology(Intel VT)虚拟化技术。目前，Intel已经发布了具有Intel VT虚拟化技术的一系列处理器产品，包括桌面平台的Pentium 4 6X2系列、Pentium D 9X0系列和Pentium EE 9XX系列，还有Core Duo系列和Core Solo系列中的部分产品，以及服务器/工作站平台上的Xeon LV系列、Xeon 5000系列、Xeon 5100系列、Xeon MP 7000系列以及Itanium 2 9000系列；同时绝大多数的Intel下一代主流处理器，包括Merom核心移动处理器，Conroe核心桌面处理器，Woodcrest核心服务器处理器，以及基于Montecito核心的Itanium 2高端服务器处理器都将支持Intel VT虚拟化技术。 而AMD方面也已经发布了支持AMD Virtualization Technology(AMD VT)虚拟化技术的一系列处理器产品，包括Socket S1接口的Turion 64 X2系列以及Socket AM2接口的Athlon 64 X2系列和Athlon 64 FX系列等等，并且绝大多数的AMD下一代主流处理器，包括即将发布的Socket F接口的Opteron都将支持AMD VT虚拟化技术。 http://wiki.ccw.com.cn/index.php/%E8%99%9A%E6%8B%9F%E5%8C%96 Virtualization From Wikipedia, the free encyclopedia Jump to: navigation, search Look up Virtualization in Wiktionary, the free dictionary. In computing, virtualization is a broad term that refers to the abstraction of computer resources: Platform virtualization, which separates an operating system from the underlying platform resources Full virtualization Hardware-assisted virtualization Partial virtualization Paravirtualization Operating system-level virtualization Resource virtualization, the virtualization of specific system resources, such as storage volumes, name spaces, and network resources Virtual memory, which allows uniform, contiguous addressing of physically separate and non-contiguous memory and disk areas Redundant array of independent disks and logical volume management, combine many disks into one large logical disk. Storage Virtualization, the process of completely abstracting logical storage from physical storage Channel bonding, the use multiple links combined to work as though they offered a single, higher-bandwidth link Network virtualization, creation of a virtualized network addressing space within or across network subnets Computer clusters and grid computing, the combination of multiple discrete computers into larger metacomputers partition (computing), is the splitting of a single resource (usually large), such as disk space or network bandwidth, into a number of smaller, more easily utilized resources of the same type Encapsulation, the hiding of resource complexity by the creation of a simplified interface Application Virtualization, the hosting of individual applications on alien hardware/software Portable application Cross-platform virtualization Emulation or simulation Virtualization Development, further work in this area Desktop virtualization, the remote manipulation of a computer desktop Virtualization can also refer to: a fictional use of this term, in Scanners (Code Lyoko) Full virtualization From Wikipedia, the free encyclopedia Jump to: navigation, search The concept of full virtualization is well established in the literature, but not always using this specific term. See virtualization regarding terminology. VirtualBox uses full virtualization Full virtualization, in computer science, is a virtualization technique used to implement a certain kind of virtual machine environment: one that provides a complete simulation of the underlying hardware. The result is a system in which all software capable of execution on the raw hardware can be run in the virtual machine. In particular, this includes all operating systems. (This is different from other forms of virtualization � which allow only certain or modified software to run within a virtual machine.) The prototypical illustration of full virtualization is in the control program of IBM's CP/CMS operating system � first demonstrated with IBM's CP-40 research system in 1967, then distributed via open source in CP/CMS in 1967-1972, and re-implemented in IBM's VM family from 1972 to the present. Each CP/CMS user was provided a simulated, stand-alone computer. Each such virtual machine had the complete capabilities of the underlying machine, and (for its user) the virtual machine was indistinguishable from a private system. This simulation was comprehensive, and was based on the Principles of Operation manual for the hardware. It thus included such elements as instruction set, main memory, interrupts, exceptions, and device access. The result was a single machine that could be multiplexed among many users. Full virtualization is only possible given the right combination of hardware and software elements. For example, it was not possible with most of IBM's System/360 series with the exception being the IBM System/360-67; nor was it possible with IBM's early System/370 system until IBM added virtual memory hardware to the System/370 series in 1972. Similarly, full virtualization was not quite possible with the x86 platform until the 2005-2006 addition of the AMD-V and IVT extensions (see x86 virtualization). Many virtual machine systems for the x86 platform came very close and claimed full virtualization even prior to the AMD-V and IVT additions. Examples include VMware Workstation, VMware Server (formerly GSX Server), VirtualBox, Parallels Desktop for Mac, Adeos, Mac-on-Linux, Win4BSD, and Win4Lin Pro. VMware, for instance, employs a technique called binary translation to automatically modify x86 software on-the-fly to replace instructions that "pierce the virtual machine" with a different, virtual machine safe sequence of instructions; this technique provides the appearance of full virtualization.[1] A key challenge for full virtualization is the interception and simulation of privileged operations, such as I/O instructions. The effects of every operation performed within a given virtual machine must be kept within that virtual machine � virtual operations cannot be allowed to alter the state of any other virtual machine, the control program, or the hardware. Some machine instructions can be executed directly by the hardware, since their effects are entirely contained within the elements managed by the control program, such as memory locations and arithmetic registers. But other instructions that would "pierce the virtual machine" cannot be allowed to execute directly; they must instead be trapped and simulated. Such instructions either access or affect state information that is outside the virtual machine. Full virtualization has proven highly successful for a) sharing a computer system among multiple users, b) isolating users from each other (and from the control program) and c) emulating new hardware to achieve improved reliability, security and productivity. [edit] See also Virtualization CP/CMS Popek and Goldberg Virtualization Requirements Native virtualization Partial virtualization Comparison of virtual machines [edit] References ^ VMware (11 Sep 2007). "Understanding Full Virtualization, Paravirtualization, and Hardware Assist" (PDF). VMware. Retrieved on 2007-12-09. See specific sources listed under virtualization and (for historical sources) CP/CMS. [edit] External links General current information about x86 Virtualization http://en.wikipedia.org/wiki/Full_virtualization