2009年2月6日星期五

Hyper-V领衔 微软虚拟化战略全面出击

 【IT168 专稿】过去,一谈到虚拟化,我们就很自然的会想到VMware、Citrix(XenSource)、Parallels(SWsoft)等公司。而今天,在这个领域,还有另外一家"重量级"的厂商不能不值得我们重点关注,那就是微软。2008年,随着其专业虚拟化工具Hyper-V的正式推出,微软已经拥有了从桌面虚拟化、服务器虚拟化到应用虚拟化、展现层虚拟化的完备的产品线。至此,其全面出击的虚拟化战略已经完全浮出水面。

  全面的虚拟化体系结构

  现在,越来越多的商业成功依赖于信息技术的有力驱动。微软中国服务器产品业务群总监符国新先生认为,对于IT专业人士来说,通过根据企业的战略目标调整计算资源,建立起灵活和智能的IT系统,使其能自动适应不断变化的业务环境,是他们追求的终极目标。微软则把这一愿景称作"动态IT",而微软进一步阐明实现"动态IT"的基础则是虚拟化技术的有效运用。

  因此,从早期的Virtual PC、Virtual Server、SoftGrid、Terminal Services、到今天Hyper-V的推出,这些看似不经意的动作,现在看来均是为其全面的虚拟化战略实施做铺垫。而经过这样一系列的铺垫,微软的从数据中心到桌面虚拟化、全面的端到端的虚拟化战略则正式部署完毕,只待开花!(图1)

  服务器虚拟化:微软Windows Server 2008操作系统的"Hyper-V"新功能把服务器虚拟技术融入操作系统。其设计方法提高了虚拟化技术的效率,能够提供更好的性能。(此技术也通过微软Hyper-V Server单独提供)。Hyper-V技术以及现有的Microsoft Virtual Server 2005 R2都支持服务器整合,支持在新硬件上运行旧操作系统和应用程序,以及跨平台可迁移应用程序的灾难恢复。

  应用虚拟化:微软的SoftGrid应用程序虚拟技术将应用程序转变成集中管理的虚拟服务,然后在需要的时间和地点把服务提供给台式机、服务器和笔记本电脑。SoftGrid通过简化应用程序管理,极大地加快了应用程序的部署、升级和打补丁。

  展现层虚拟化:使用微软的Windows Server Terminal Services,桌面应用程序可以运行在一台共享服务器上,将用户界面呈现在远程用户的终端上,如台式计算机或瘦客户机。

  桌面虚拟化:微软的虚拟PC通过在一台机器上支持多种操作系统,实现了在个人电脑上运行互不兼容的应用程序,这加速了新软件和新系统的开发与测试。此外,随着专为宿主桌面架构(也被称为"桌面虚拟架构")开发的Windows Vista Enterprise Centralized Desktop的推出,整个桌面可以运行在一台服务器上,然后被传送到另外一台远程计算机的桌面上。

  有人说过,没有受到良好管理的虚拟化比不使用虚拟化更危险。这话一点不假,构建广泛使用的虚拟化构建基础结构确实会带来许多商业优势,但如果没有正确管理工具,策略和进程,那么在虚拟化的过程中就可能会出现一些问题。所以当企业规划虚拟基础结构时,就有必要一个强有力的管理工具。而我们了解到,Microsoft则提供了一个全面的、端到端的工具集,用于创建、设置、管理和保护企业的虚拟及物理基础架构,即System Center。该工具提供的管理软件使IT专业人员能够管理全部的计算资源,包括虚拟资源和物理资源。System Center提供跨桌面、服务器、操作系统和应用程序的虚拟环境与物理环境的配置、监控和备份工具。从而实现自动作业,降低成本,提高应用程序的可用性。 (图2)

  采用正确的管理工具来管理物理和虚拟基础结构,对企业来说是至关重要的。 Microsoft System Center通过统一的、熟悉的界面,提供了一套全面、集成的工具来管理物理服务器、虚拟服务器、存储和网络资产、桌面和应用程序。

 

2009年2月4日星期三

瘾科学:十一分钟带你进入十次元的世界



这是小姜在乱逛的时候发现的一个影片。我们平常是生活在一个四次元(亦称四维)的世界,由三次元的空间再加上一次元的时间所组成。但弦理论(String Theory)却似乎显示我们生活的世界有 11 个次元(零次元到十次元),而宇宙中发生的一切都是受到第十次元中振动的超弦的影响而发生的。

第十次元?振动?弦?一想到这种概念,脑袋里自动产生的想象,似乎是在一个完全黑的空间里,有一堆小蚯蚓在扭动。小姜一度认为理解四次元以上的世界是不可能的,但这个由名为「Imagining the Tenth Dimension」的书的作者 Bob Bryson 所弄的影片却重复利用了我们熟悉的四次元世界,展示更高的次元给我们看,同时解释了为什么没有比十次元更高的次元,以及为什么宇宙中发生的一切都是受到第十次元中振动的弦的影响(而不是第九,或第八)。

我想,一般人看完这个影片之后,应该会是四个结果中的一个:理解宇宙的规则,破碎虚空;不理解宇宙的规则,走火入魔;不理解宇宙的规则,浪费了生命中的 11 分钟;和...睡着。

小姜显然是浪费了 11 分钟的那种(要不是还要写这篇文章,大概就睡着了),但不知道有没有哪位大神,完全理解十次元的世界的?XD


第零次元:点
第一次元:线
第二次元:面
第三次元:立体

将三次元世界缩成点

第四次元:时间(三次元世界拉成线)
第五次元:所有时间轴分支的可能性(三次元世界构成的面)
第六次元:在时间轴平面上跳跃的可能性(三次元世界构成的立体),即空间在所有的时间点所组成的「无限宇宙」。

将无限宇宙缩成点

第七次元:其它可能和我们世界规则完全不同的的宇宙(无限宇宙拉成线)
第八次元:所有和我们世界规则不同的宇宙的集合(无限宇宙构成的面)
第九次元:在完全不同的宇宙间跳跃的可能性(无限宇宙组成的立体)

将第九次元缩成点

第十次元:将所有可能的宇宙集合成一个点看待,就是第十次元了。因为所有可能的宇宙都已经算在里头了,自然更高次元是不可能 -- 或至少只能这样理解了。

看起来,似乎对任何一个次元的存在来说,更高一个次元的存在都拥有神一般的力量啊 @@

Tenth Dimension


In string theory, physicists tell us that the subatomic particles that make up our universe are created within ten spatial dimensions (plus an eleventh dimension of "time") by the vibrations of exquisitely small "superstrings". The average person has barely gotten used to the idea of there being four dimensions: how can we possibly imagine the tenth?

Imagining the Ten Dimensions

The flash version of this website (www.tenthdimension.com)  provides an interactive set of animations with narration and sound effects which explain the basic concepts from chapter one of the book. The media-rich nature of these animations is not recommended for viewing with a dialup connection because of long load times. Below is a transcript of the narration from those animations. The ideas presented here come from chapter one of a new book called "Imagining the Tenth Dimension: a new way of thinking about time and space", written by Rob Bryanton.

0. A point (no dimension)

We start with a point. Like the “point” we know from geometry, it has no size, no dimension. It’s just an imaginary idea that indicates a position in a system.

1. The first dimension – a line

A second point, then, can be used to indicate a different position, but it, too, is of indeterminate size. To create the first dimension, all we need is a line joining any two points. A first dimensional object has length only, no width or depth.

2. The Second Dimension – A Split

If we now take our first dimensional line and draw a second line crossing the first, we’ve entered the second dimension. The object we’re representing now has a length and a width, but no depth. To help us with imagining the higher dimensions, we’re going to represent our second dimensional object as being created using a second line which branches off from the first.

Now, let’s imagine a race of two-dimensional creatures called “Flatlanders”. What would it be like to be a Flatlander living in their two-dimensional world? A two-dimensional creature would have only length and width, as if they were the royalty on an impossibly flat playing card. Picture this: a Flatlander couldn’t possibly have a digestive tract, because the pipe from their mouth to their bottom would divide them into two pieces! And a Flatlander trying to view our three-dimensional world would only be able to perceive shapes in two-dimensional cross-sections. A balloon passing through the Flatlander’s world, for instance, would start as a tiny dot, become a hollow circle which inexplicably grows to a certain size, then shrinks back to a dot before popping out of existence. And we three-dimensional human beings would seem very strange indeed to a Flatlander.

3. The Third Dimension – A Fold

Imagining the third dimension is the easiest for us because every moment of our lives that is what we’re in. A three dimensional object has length, width, and height. But here’s another way to describe the third dimension: if we imagine an ant walking across a newspaper which is lying on a table, we can pretend that the ant is a Flatlander, walking along on a flat two-dimensional newspaper world. If that paper is now folded in the middle, we create a way for our Flatlander Ant to “magically” disappear from one position in his two-dimensional world and be instantly transported to another. We can imagine that we did this by taking a two-dimensional object and folding it through the dimension above, which is our third dimension. Once again, it’ll be more convenient for us as we imagine the higher dimensions if we can think of the third dimension in this way: the third dimension is what you “fold through” to jump from one point to another in the dimension below.

4. The Fourth Dimension – A Line

Okay. The first three dimensions can be described with these words: “length, width, and depth”. What word can we assign to the fourth dimension? One answer would be, “duration”. If we think of ourselves as we were one minute ago, and then imagine ourselves as we are at this moment, the line we could draw from the “one-minute-ago version” to the “right now” version would be a line in the fourth dimension. If you were to see your body in the fourth dimension, you would be like a long undulating snake, with your embryonic self at one end and your deceased self at the other. But because we live from moment to moment in the third dimension, we are like our second dimensional Flatlanders. Just like that Flatlander who could only see two-dimensional cross-sections of objects from the dimension above, we as three-dimensional creatures can only see three-dimensional cross-sections of our fourth-dimensional self.

5. The Fifth Dimension – A Split

One of the most intriguing aspects of there being one dimension stacked on another is that down here in the dimensions below we can be unaware of our motion in the dimensions above. Here’s a simple example: if we make a Möbius strip (take a long strip of paper, add one twist to it and tape the ends together) and draw a line down the length of it, our line will eventually be on both sides of the paper before it meets back with itself. It appears, somewhat amazingly, that the strip has only one side, so it must be a representation of a two-dimensional object. And this means that a two-dimensional Flatlander traveling down the line we just drew would end up back where they started without ever feeling like they had left the second dimension. In reality, they would be looping and twisting in the third dimension, even though to them it felt like they were traveling in a straight line.
 
The fourth dimension, time, feels like a straight line to us, moving from the past to the future. But that straight line in the fourth dimension is, like the Möbius strip, actually twisting and turning in the dimension above. So, the long undulating snake that is us at any particular moment will feel like it is moving in a straight line in time, the fourth dimension, but there will actually be, in the fifth dimension, a multitude of paths that we could branch to at any given moment. Those branches will be influenced by our own choice, chance, and the actions of others.

Quantum physics tells us that the subatomic particles that make up our world are collapsed from waves of probability simply by the act of observation. In the picture we are drawing for ourselves here, we can now start to see how each of us are collapsing the indeterminate wave of probable futures contained in the fifth dimension into the fourth dimensional line that we are experiencing as “time”.

6. The Sixth Dimension – A Fold

What if you wanted to go back into your own childhood and visit yourself? We can imagine folding the fourth dimension through the fifth, jumping back through time and space to get there. But what if you wanted to get to the world where, for example, you had created a great invention as a child that by now had made you famous and rich? We can imagine our fourth-dimensional selves branching out from our current moment into the fifth dimension, but no matter where you go from here the “great child inventor” timeline is not one of the available options in your current version of time -- “you can’t get there from here” -- no matter how much choice, chance, and the actions of others become involved. 

There are only two ways you could get to that world – one would be to travel back in time, somehow trigger the key events that caused you to come up with your invention, then travel forward in the fifth dimension to see one of the possible new worlds that might have resulted. But that would be taking the long way. The shortcut we could take would involve us folding the fifth dimension through the sixth dimension, which allows us to instantly jump from our current position to a different fifth dimensional line.

7. The Seventh Dimension – A Line

In our description of the fourth dimension, we imagined taking the dimension below and conceiving of it as a single point. The fourth dimension is a line which can join the universe as it was one minute ago to the universe as it is right now. Or in the biggest picture possible, we could say that the fourth dimension is a line which joins the big bang to one of the possible endings of our universe.

Now, as we enter the seventh dimension, we are about to imagine a line which treats the entire sixth dimension as if it were a single point. To do that, we have to imagine all of the possible timelines which could have started from our big bang joined to all of the possible endings for our universe (a concept which we often refer to as infinity), and treat them all as a single point. So, for us, a point in the seventh dimension would be infinity – all possible timelines which could have or will have occurred from our big bang.

8. The Eighth Dimension – A Split

When we describe infinity as being a “point” in the seventh dimension, we are only imagining part of the picture. If we’re drawing a seventh dimensional line, we need to be able to imagine what a different “point” in the seventh dimension is going to be, because that’s what our line is going to be joined to. But how can there be anything more than infinity? The answer is, there can be other completely different infinities created through initial conditions which are different from our own big bang. Different initial conditions will create different universes where the basic physical laws such as gravity or the speed of light are not the same as ours, and the resulting branching timelines from that universe’s beginning to all of its possible endings will create an infinity which is completely separate from the one which is associated with our own universe. So the line we draw in the seventh dimension will join one of these infinities to another. And, as boggling as the magnitude of what we are exploring here might be, if we were to branch off from that seventh dimensional line to draw a line to yet another infinity, we would then be entering the eighth dimension.

9. The Ninth Dimension – A Fold

As we’ve explored already, we can jump from one point in any dimension to another simply by folding it through the dimension above. If our ant on the newspaper were a two-dimensional Flatlander, then folding his two-dimensional world through the third dimension would allow him to magically disappear from one location and appear in a different one. As we’re now imagining the ninth dimension, the same rules would apply – if we were to be able to instantaneously jump from one eighth dimensional line to another, it would be because we were able to fold through the ninth dimension.

10. The Tenth Dimension – A Point?

Before we discussed the first dimension, we could say that we first started out with dimension zero, which is the geometrical concept of the “point”. A point indicates a location in a system, and each point is of indeterminate size. The first dimension then, takes two of these “points” and joins them with a line.
 
When we imagined the fourth dimension, it was as if we were treating the entirety of three-dimensional space in a particular state as a single point, and drawing a fourth-dimensional line to another point representing space as it is in a different state. We often refer to the line we have just drawn as “time”.

Then in the seventh dimension, we treated all of the possible timelines which could be generated from our big bang as if this were a single point, and imagined drawing a line to a point representing all of the possible timelines for a completely different universe.

Now, as we enter the tenth dimension, we have to imagine all of the possible branches for all the possible timelines of all the possible universes and treat that as a single point in the tenth dimension. Whew! So far, so good. But this is where we hit a roadblock: if we’re going to imagine the tenth dimension as continuing the cycle, and being a line, then we’re going to have to imagine a different point that we can draw that line to.  But there’s no place left to go! By the time we have imagined all possible timelines for all possible universes as being a single point in the tenth dimension, it appears that our journey is done.

In String theory, physicists tell us that Superstrings vibrating in the tenth dimension are what create the subatomic particles which make up our universe, and all of the other possible universes as well. In other words, all possibilities are contained within the tenth dimension, which would appear to be the concept we have just built for ourselves as we imagined the ten dimensions, built one upon another.

10美元PC名为Sakshat 或将使用ARM平台

不久前,印度政府将推出10美元(约合人民币68元)笔记本电脑的消息已经在互联网上传开。日前,该电脑的名称、参数和售价已经泄露出来。印度政府把这台低价笔记本电脑叫做Sakshat,意即“在你眼前”。它配备了2GB内存、2GB闪存和无线网卡,并将预装Linux操作系统,在能够方便的连接到Internet的同时也大大节省了成本。

Sakshat目前正处于开发状态,因此其正式发布时间现在暂时还没有确定。但有消息称它的最终成本会达到20美元(约合人民币136元),因此在其成本降低到10美元之前,印度政府将会拿出一部分资金来补贴这部分差额,使这台超低价笔记本电脑能够尽快普及。

印度|笔记本电脑|低价

图为One Laptop Per Child XO笔记本电脑

事实上,即使是20美元这个价格,我们仍然无法确定笔记本电脑的制造商是如何做到的。目前英特尔最便宜的Atom处理器也要26美元(约合人民币177元),因此Sakshat很可能会使用在手机上常见的ARM平台来尽可能降低成本。而将预装Linux操作系统这个信息也从侧面证实了这一点。

相比之下,售价200美元(约合人民币1360元)的One Laptop Per Child(每个孩子一台电脑计划)XO笔记本电脑使用了非常低端的AMD Geode处理器,内建闪存芯片,并预装Linux操作系统。