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  • Gilda Garretón, a Java Developer and Parallelism Computing Researcher

    - by Yolande
    In a new interview titled “Gilda Garretón, a Java Developer and Parallelism Computing Research,” Garretón shares her first-hand experience developing with Java and Java 7 for very large-scale integration (VLSI) of computer-aided design (CAD). Garretón gives an insightful overview of how Java is contributing to the parallelism development and to the Electric VLSI Design Systems, an open source VLSI CAD application used as a research platform for new CAD algorithms as well as the research flow for hardware test chips.  Garretón considers that parallelism programming is hard and complex, yet important developments are taking place.  "With the addition of the concurrent package in Java SE 6 and the Fork/Join feature in Java SE 7, developers have a chance to rely more on existing frameworks and dedicate more time to the essence of their parallel algorithms." Read the full article here  

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  • Parallel Computing Platform Developer Lab

    This is an exciting announcement that I must share: "Microsoft Developer & Platform Evangelism, in collaboration with the Microsoft Parallel Computing Platform product team, is hosting a developer lab at the Platform Adoption Center on April 12-15, 2010.  This event is for Microsoft Partners and Customers seeking to incorporate either .NET Framework 4 or Visual C++ 2010 parallelism features into their new or existing applications, and to gain expertise with new Visual Studio 2010 tools...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • BizTalk and Cloud computing

    - by Suresh Behera
    Now a day I am more thinking on cloud computing,biztalk ,appfabrick,health care,HPC and data bursting. I guess I should have my own lab now and wish have enough time to play around. I will start writing more blog abound this subject slowly .I am in process to setting up a very nicely distributed and decoupled environment for biztalk .I got my first surprise.I will do more VM Role setup with windows Azure 4.0 . (Installation on Biztalk 2010 and database on different server.)   Thanks, Suresh...(read more)

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  • Languages/Methods to Learn for Scientific Computing?:

    - by Zéychin
    I'm a second-semester Junior working towards a Computer Science degree with a Scientific Computing concentration and a Mathematics degree with a concentration on Applied Discrete Mathematics. So, number crunching and such rather than a bunch of regular expressions, interface design, and networking. I've found that I'm not learning new relevant languages from my coursework and am interested in what the community would recommend me to learn. I know as far as programming methods go, I need to learn more about parallelizing programs, but if there's anything else you can recommend, I would appreciate it. Here's a list of the languages with which I am very experienced (web technologies omitted as they barely apply here). Any recommendations for additional languages I should learn would be very much appreciated!: Java C C++ Fortran77/90/95 Haskell Python MATLAB

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  • Cloud Computing in words of one syllable

    - by harry.foxwell(at)oracle.com
    A colleague of mine challenged me to describe Cloud Computing in words of one syllable so that even his 80-year-old mother-in-law could understand the concept.  Hmmmm...The Cloud lets you do all your work on the Web or on your own net. It lets you set up your own work; no one has to set it up for you.  When you need more disk space, the cloud makes it for you.  When you need more speed, the cloud adds more gear to make your jobs go fast.  You share the cloud with more than just your own work, and you just pay for what you use.  The cloud is not new; this type of work has been done for years; just the word is new.  Now you know what the cloud is.  Or not.

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  • Studying Quantum Computing?

    - by The_Neo
    Hi I am a computer science student currently on an internship and I have been thinking more and more about looking into working for a company / places that is developing quantum computers/ing when I graduate. Here is my problem, I have a pretty solid grasp of mathematics involved in Comp Sci and enjoy learning about more Comp Sci theory but in doing some minor research about Quantum Computing it seems to me to be more about hardware and I have always leant more to the software side of things. I haven't studied any physics since high school so I am wondering if I would be suitable to work in such a field with a Comp Sci degree, is it a field more aimed at physicists?

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  • Distributed Computing - Hybrid Systems Considerations

    When the Cloud was new, it was often presented as an 'all or nothing' solution. Nowadays, the canny Systems Architect will exploit the best advantages of 'cloud' distributed computing in the right place, and use in-house services where most appropriate. So what are the issues that govern these architectural decisions? What can SQL Monitor 3.2 monitor?Whatever you think is most important. Use custom metrics to monitor and alert on data that's most important for your environment. Find out more.

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  • Where has Cloud Computing gone?

    - by Srikar
    I have been hearing about this term for close to 5 years now. I have read about services from Microsoft (Azure), but I have never saw it adopted in the mainstream usage. The thing I am trying to understand is this: What happened to cloud computing? Is the infrastructure at present insufficient to implement this? Is it still in its infancy? Is it being used in other forms, like all the services Google seems to provide (plus Plus Google OS, etc)? If it has failed, then why?

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  • Cloud Computing and Data Utilization

    - by Ahsan Alam
    Someone recently asked me “is cloud computing going to change the way we perceive data?”. My first instinct was “off course”; but I restrained myself and thought for a moment. Then my answer was “no”. Why do I feel that way? Technology and business have evolved quite a bit in the past few decades; however, the need to effectively view and utilize data hasn't changed. It is not uncommon to see many organization to rely on multiple database management systems (DBMS). Applications and systems are often built to utilize information from all these data sources, and effectively present them to users. In addition to multiple DBMS, corporations are also housing their systems across numerous data centers. In fact, systems and data can reside anywhere around the world with the advent of globalization. Cloud based systems have simply provided us a different place to maintain our data, nothing more. Hosting costs, security and accessibility are different issues; however, the way we utilize and view these data remains the same.

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  • JOGL hardware based shadow mapping - computing the texture matrix

    - by axel22
    I am implementing hardware shadow mapping as described here. I've rendered the scene successfully from the light POV, and loaded the depth buffer of the scene into a texture. This texture has correctly been loaded - I check this by rendering a small thumbnail, as you can see in the screenshot below, upper left corner. The depth of the scene appears to be correct - objects further away are darker, and that are closer to the light are lighter. However, I run into trouble while rendering the scene from the camera's point of view using the depth texture - the texture on the polygons in the scene is rendered in a weird, nondeterministic fashion, as shown in the screenshot. I believe I am making an error while computing the texture transformation matrix, but I am unsure where exactly. Since I have no matrix utilities in JOGL other then the gl[Load|Mult]Matrix procedures, I multiply the matrices using them, like this: void calcTextureMatrix() { glPushMatrix(); glLoadIdentity(); glLoadMatrixf(biasmatrix, 0); glMultMatrixf(lightprojmatrix, 0); glMultMatrixf(lightviewmatrix, 0); glGetFloatv(GL_MODELVIEW_MATRIX, shadowtexmatrix, 0); glPopMatrix(); } I obtained these matrices by using the glOrtho and gluLookAt procedures: glLoadIdentity() val wdt = width / 45 val hgt = height / 45 glOrtho(wdt, -wdt, -hgt, hgt, -45.0, 45.0) glGetFloatv(GL_MODELVIEW_MATRIX, lightprojmatrix, 0) glLoadIdentity() glu.gluLookAt( xlook + lightpos._1, ylook + lightpos._2, lightpos._3, xlook, ylook, 0.0f, 0.f, 0.f, 1.0f) glGetFloatv(GL_MODELVIEW_MATRIX, lightviewmatrix, 0) My bias matrix is: float[] biasmatrix = new float[16] { 0.5f, 0.f, 0.f, 0.f, 0.f, 0.5f, 0.f, 0.f, 0.f, 0.f, 0.5f, 0.f, 0.5f, 0.5f, 0.5f, 1.f } After applying the camera projection and view matrices, I do: glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR) glTexGenfv(GL_S, GL_EYE_PLANE, shadowtexmatrix, 0) glEnable(GL_TEXTURE_GEN_S) for each component. Does anybody know why the texture is not being rendered correctly? Thank you.

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  • Are you at Super Computing 10?

    - by Daniel Moth
    Like last year, I was going to attend SC this year, but other events are unfortunately keeping me here in Seattle next week. If you are going to be in New Orleans, have fun and be sure not to miss out on the following two opportunities. MPI Debugging UX Study Throughout the week, my team is conducting 90-minute studies on debugging MPI applications within Visual Studio. In exchange for your feedback (under NDA) you will receive a Microsoft Gratuity (and the knowledge that you are impacting the development of Visual Studio). If you are interested, sign up at the Microsoft Information Desk in the Exhibitor Hall during exhibit hours. Outside of exhibit hours, send email to [email protected]. If you took part in the GPGPU study, this is very similar except it is for MPI. Microsoft High Performance Computing Summit On Monday 15th, the Microsoft annual user group meeting takes place. Shuttle transportation and lunch is provided. For full details of this event and to register, please visit the official event page. Comments about this post welcome at the original blog.

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  • Cloud computing - database loading question

    - by workwise
    Following is the situation, I want to know whether what I want is possible in cloud computing and is it the best way for me: 1) My main site has a Database with tables with millions of rows, and entries are added almost every second. 2) I will setup a mysql mirror, so there will be a backup database always in sync with the main one. 3) There are few tens of thousands of images- growing. So say total size of images few tens of gigabytes. I will be keeping the image data also in sync on the backup server. 4) There can be short periods where traffic can go 100X the average traffic. 5) I will be using memcache heavily - most database and even frequently used disk files/images will be in RAM. I want that the main site runs on a dedicated server. The backup server is say an Amazon EC2 instance. Now note that since it is live backup, I need to run a small instance continuously. I want that when I anticipate high traffic, I should be able to run a large instance on the cloud and transfer the traffic there. The main point is - I do not want to spend time in "loading" the database on the large instance, as it typically can take few minutes or even hours (experience). So is it possible to just scale the memory/CPU on demand, and not having to load the database or sync up the filesystem? I want to setup my backup scripts etc just ONCE. Thanks JP

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  • What Computing/Programming Qualifications should I aspire for

    - by indevel
    I am a computing science post graduate in my first job from after my degree. During my 12 month review my boss posed the question "What can we do for you in terms of progressing your career?". This got me thinking, after university I hadn't really thought about what other qualifications were available. So this is my question, what courses/qualifications should I be looking to do. Which are highly regarded and which would be really useful to complete. I've searched Google it but all I see is a jumble of courses with no idea of the credibility of each. Any help is much appreciated. I'm traditionally a systems architect, but with this job I've turned to more embedded work so Id like to edge towards electronics, embedded programming, real time OS to help with my work also it would be more likely to be accepted if it was related to my job. Finally UK based courses/ qualifications are a must as travel is probably out of the question. Help me grow as a programmer.

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  • Efficient process SQL Server and numerical methods library

    - by darkcminor
    Is there a way to comunicate a numeric method library, that can exploit all .net's (numerical methods called by .net that does SQL Server things) habilities?, What library do you recomend, maybe using MATLAB, R? How to comunicate SQL Server and .net with such library or libraries? Do you have an example? What steps must be followed to make the link between numerical libraries, .net and SQL Server

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  • convert Arabic numerical to English

    - by hamitay
    i am looking for a way to convert the Arabic numerical string "??????????" to an English numerical string "0123456789" Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click dim Anum as string ="??????????" dim Enum as string =get_egnlishNum(Anum) End Sub private function get_egnlishNum(byval _Anum as string) as string '' converting code end function

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  • Are we ready for the Cloud computing era?

    - by andrewkatumba
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} "Elite?" developer circles are abuzz with the notion of Cloud computing . The increasing bandwidth, the desire for faster and leaner operations and ofcourse the need for outsourcing non core it related business requirements e.g wordprocessing, spreadsheets, data backups. In strolls Chrome OS (am sure other similar OSes will join with their own wagons for us to jump on), offering just that, internet based services(more like a repository of), quick efficient and "reliable" and for the most part cheap and often time even free! And we all go rhapsodic!  It boils down to the age old dilemma, "if the cops are so busy protecting us then who will protect them" (even the folks back at Hollywood keep us reminded)! Who is going to ensure that these internet based services do not go down(either intentionally or by some malicious third party) leading to a multinational colossal disaster .At the risk of sounding pessimistic,  IT IS NOT AN ISSUE OF TRUST, this is but a mere case of Murphy's Law!  What then? Should the "cloud" be trusted to this extent at this time?  This is an era where challenges are rapidly solved with lightning promptness to "beat the competition", my hope is that our solutions are not just creating problems that we may not be able to solve!  Keeping my ear on the Ground.

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  • Windows Azure Learning Plan - Security

    - by BuckWoody
    This is one in a series of posts on a Windows Azure Learning Plan. You can find the main post here. This one deals with Security for  Windows Azure.   General Security Information Overview and general  information about Windows Azure Security - what it is, how it works, and where you can learn more. General Security Whitepaper – answers most questions http://blogs.msdn.com/b/usisvde/archive/2010/08/10/security-white-paper-on-windows-azure-answers-many-faq.aspx Windows Azure Security Notes from the Patterns and Practices site http://blogs.msdn.com/b/jmeier/archive/2010/08/03/now-available-azure-security-notes-pdf.aspx Overview of Azure Security http://www.windowsecurity.com/articles/Microsoft-Azure-Security-Cloud.html Azure Security Resources http://reddevnews.com/articles/2010/08/19/microsoft-releases-windows-azure-security-resources.aspx Cloud Computing Security Considerations http://www.microsoft.com/downloads/en/details.aspx?FamilyID=68fedf9c-1c27-4642-aa5b-0a34472303ea&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+MicrosoftDownloadCenter+%28Microsoft+Download+Center Security in Cloud Computing – a Microsoft Perspective http://www.microsoft.com/downloads/en/details.aspx?FamilyID=7c8507e8-50ca-4693-aa5a-34b7c24f4579&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+MicrosoftDownloadCenter+%28Microsoft+Download+Center Physical Security for Microsoft’s Online Computing Information on the Infrastructure and Locations for Azure Physical Security. The Global Foundation Services Group at Microsoft handles physical security http://www.globalfoundationservices.com/security/index.html Microsoft’s Security Response Center http://www.microsoft.com/security/msrc/ Software Security for Microsoft’s Online Computing Steps we take as a company to develop secure software Windows Azure is developed using the Trustworthy Computing Initiative http://www.microsoft.com/about/twc/en/us/default.aspx and  http://msdn.microsoft.com/en-us/library/ms995349.aspx Identity and Access in the Cloud http://blogs.msdn.com/b/technology_titbits_by_rajesh_makhija/archive/2010/10/29/identity-and-access-in-the-cloud.aspx Security Steps you should take While Microsoft takes great pains to secure the infrastructure, platform and code for Windows Azure, you have a responsibility to write secure code. These pointers can help you do that. Securing your cloud architecture, step-by-step http://technet.microsoft.com/en-us/magazine/gg296364.aspx Security Guidelines for Windows Azure http://redmondmag.com/articles/2010/06/15/microsoft-issues-security-guidelines-for-windows-azure.aspx  Best Practices for Windows Azure Security http://blogs.msdn.com/b/vbertocci/archive/2010/06/14/security-best-practices-for-developing-windows-azure-applications.aspx Active Directory and Windows Azure http://blogs.msdn.com/b/plankytronixx/archive/2010/10/22/projecting-your-active-directory-identity-to-the-azure-cloud.aspx Understanding Encryption (great overview and tutorial) http://blogs.msdn.com/b/plankytronixx/archive/2010/10/23/crypto-primer-understanding-encryption-public-private-key-signatures-and-certificates.aspx Securing your Connection Strings (SQL Azure) http://blogs.msdn.com/b/sqlazure/archive/2010/09/07/10058942.aspx Getting started with Windows Identity Foundation (WIF) quickly http://blogs.msdn.com/b/alikl/archive/2010/10/26/windows-identity-foundation-wif-fast-track.aspx

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  • Computing a normal matrix in conjunction with gluLookAt

    - by Chris Smith
    I have a hand-rolled camera class that converts yaw, pitch, and roll angles into a forward, side, and up vector suitable for calling gluLookAt. Using this camera class I can modify the model-view matrix to move about the 3D world just fine. However, I am having trouble when using this camera class (and associated model-view matrix) when trying to perform directional lighting in my vertex shader. The problem is that the light direction, (0, 1, 0) for example, is relative to where the 'camera is looking' and not the actual world coordinates. (Or is this eye coordinates vs. model coordinates?) I would like the light direction to be unaffected by the camera's viewing direction. For example, when the camera is looking down the Z axis the ground is lit correctly. However, if I point the camera straight at the ground, then it goes dark. This is (I think) because the light direction is parallel with the camera's 'up' vector which is perpendicular with the ground's normal vector. I tried computing the normal matrix without taking the camera's model view into account, but then none of my objects were rotated correctly. Sorry if this sounds vague. I suspect there is a straight forward answer, but I'm not 100% clear on how the normal matrix should be used for transforming vertex normals in my vertex shader. For reference, here is pseudo code for my rendering loop: pMatrix = new Matrix(); pMatrix = makePerspective(...) mvMatrix = new Matrix() camera.apply(mvMatrix); // Calls gluLookAt // Move the object into position. mvMatrix.translatev(position); mvMatrix.rotatef(rotation.x, 1, 0, 0); mvMatrix.rotatef(rotation.y, 0, 1, 0); mvMatrix.rotatef(rotation.z, 0, 0, 1); var nMatrix = new Matrix(); nMatrix.set(mvMatrix.get().getInverse().getTranspose()); // Set vertex shader uniforms. gl.uniformMatrix4fv(shaderProgram.pMatrixUniform, false, new Float32Array(pMatrix.getFlattened())); gl.uniformMatrix4fv(shaderProgram.mvMatrixUniform, false, new Float32Array(mvMatrix.getFlattened())); gl.uniformMatrix4fv(shaderProgram.nMatrixUniform, false, new Float32Array(nMatrix.getFlattened())); // ... gl.drawElements(gl.TRIANGLES, this.vertexIndexBuffer.numItems, gl.UNSIGNED_SHORT, 0); And the corresponding vertex shader: // Attributes attribute vec3 aVertexPosition; attribute vec4 aVertexColor; attribute vec3 aVertexNormal; // Uniforms uniform mat4 uMVMatrix; uniform mat4 uNMatrix; uniform mat4 uPMatrix; // Varyings varying vec4 vColor; // Constants const vec3 LIGHT_DIRECTION = vec3(0, 1, 0); // Opposite direction of photons. const vec4 AMBIENT_COLOR = vec4 (0.2, 0.2, 0.2, 1.0); float ComputeLighting() { vec4 transformedNormal = vec4(aVertexNormal.xyz, 1.0); transformedNormal = uNMatrix * transformedNormal; float base = dot(normalize(transformedNormal.xyz), normalize(LIGHT_DIRECTION)); return max(base, 0.0); } void main(void) { gl_Position = uPMatrix * uMVMatrix * vec4(aVertexPosition, 1.0); float lightWeight = ComputeLighting(); vColor = vec4(aVertexColor.xyz * lightWeight, 1.0) + AMBIENT_COLOR; } Note that I am using WebGL, so if the anser is use glFixThisProblem(...) any pointers on how to re-implement that on WebGL if missing would be appreciated.

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  • Searching for cluster computation framework

    - by petkov_d
    I have a library, written in C#, containing one method: Response CalculateSomething(Request); The execution time of this method is relatively large, and there are a lot of responses that should be processed. I want to use a "cluster", spread this DLL to different machines (nodes) in this "cluster" and write some controller that will distribute responses to the nodes. There should be mechanism that perevent losing task because of node crush, load balancing. Can someone suggest framework that addresses this issue? P.S. There is a framework Qizmt written in C# but I think MapReduce is not good for the above scenario

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  • Your thoughts on Best Practices for Scientific Computing?

    - by John Smith
    A recent paper by Wilson et al (2014) pointed out 24 Best Practices for scientific programming. It's worth to have a look. I would like to hear opinions about these points from experienced programmers in scientific data analysis. Do you think these advices are helpful and practical? Or are they good only in an ideal world? Wilson G, Aruliah DA, Brown CT, Chue Hong NP, Davis M, Guy RT, Haddock SHD, Huff KD, Mitchell IM, Plumbley MD, Waugh B, White EP, Wilson P (2014) Best Practices for Scientific Computing. PLoS Biol 12:e1001745. http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001745 Box 1. Summary of Best Practices Write programs for people, not computers. (a) A program should not require its readers to hold more than a handful of facts in memory at once. (b) Make names consistent, distinctive, and meaningful. (c) Make code style and formatting consistent. Let the computer do the work. (a) Make the computer repeat tasks. (b) Save recent commands in a file for re-use. (c) Use a build tool to automate workflows. Make incremental changes. (a) Work in small steps with frequent feedback and course correction. (b) Use a version control system. (c) Put everything that has been created manually in version control. Don’t repeat yourself (or others). (a) Every piece of data must have a single authoritative representation in the system. (b) Modularize code rather than copying and pasting. (c) Re-use code instead of rewriting it. Plan for mistakes. (a) Add assertions to programs to check their operation. (b) Use an off-the-shelf unit testing library. (c) Turn bugs into test cases. (d) Use a symbolic debugger. Optimize software only after it works correctly. (a) Use a profiler to identify bottlenecks. (b) Write code in the highest-level language possible. Document design and purpose, not mechanics. (a) Document interfaces and reasons, not implementations. (b) Refactor code in preference to explaining how it works. (c) Embed the documentation for a piece of software in that software. Collaborate. (a) Use pre-merge code reviews. (b) Use pair programming when bringing someone new up to speed and when tackling particularly tricky problems. (c) Use an issue tracking tool. I'm relatively new to serious programming for scientific data analysis. When I tried to write code for pilot analyses of some of my data last year, I encountered tremendous amount of bugs both in my code and data. Bugs and errors had been around me all the time, but this time it was somewhat overwhelming. I managed to crunch the numbers at last, but I thought I couldn't put up with this mess any longer. Some actions must be taken. Without a sophisticated guide like the article above, I started to adopt "defensive style" of programming since then. A book titled "The Art of Readable Code" helped me a lot. I deployed meticulous input validations or assertions for every function, renamed a lot of variables and functions for better readability, and extracted many subroutines as reusable functions. Recently, I introduced Git and SourceTree for version control. At the moment, because my co-workers are much more reluctant about these issues, the collaboration practices (8a,b,c) have not been introduced. Actually, as the authors admitted, because all of these practices take some amount of time and effort to introduce, it may be generally hard to persuade your reluctant collaborators to comply them. I think I'm asking your opinions because I still suffer from many bugs despite all my effort on many of these practices. Bug fix may be, or should be, faster than before, but I couldn't really measure the improvement. Moreover, much of my time has been invested on defence, meaning that I haven't actually done much data analysis (offence) these days. Where is the point I should stop at in terms of productivity? I've already deployed: 1a,b,c, 2a, 3a,b,c, 4b,c, 5a,d, 6a,b, 7a,7b I'm about to have a go at: 5b,c Not yet: 2b,c, 4a, 7c, 8a,b,c (I could not really see the advantage of using GNU make (2c) for my purpose. Could anyone tell me how it helps my work with MATLAB?)

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  • Cloud computing over Client-server: differences, cons and pros ?

    - by Vimvq1987
    As far as I know, Cloud computing might be a evolution in software architect, and it will replace some current architectures, such as client-server. These two architecture seem to share similarities for me (I know very little about both), but I don't know the differences between them. What are the cons and pros of cloud computing over client-server architecture? Thank you so much.

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  • What Parallel computing APIs take good use of sockets?

    - by Ole Jak
    What Parallel computing APIs take good use of sockets? So my programm uses soskets, what Parallel computing APIs I can use that would help me but will not obligate me to go from sockets to anything else... I mean when we are on claster with some special, not socket infrastructure sistem that API emulates something like socket but uses that infrustructure (so programm peforms much faster then on sockets, but keeps having nice soskets API)

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  • Azure Grid Computing - Worker Roles as HPC Compute Nodes

    - by JoshReuben
    Overview ·        With HPC 2008 R2 SP1 You can add Azure worker roles as compute nodes in a local Windows HPC Server cluster. ·        The subscription for Windows Azure like any other Azure Service - charged for the time that the role instances are available, as well as for the compute and storage services that are used on the nodes. ·        Win-Win ? - Azure charges the computer hour cost (according to vm size) amortized over a month – so you save on purchasing compute node hardware. Microsoft wins because you need to purchase HPC to have a local head node for managing this compute cluster grid distributed in the cloud. ·        Blob storage is used to hold input & output files of each job. I can see how Parametric Sweep HPC jobs can be supported (where the same job is run multiple times on each node against different input units), but not MPI.NET (where different HPC Job instances function as coordinated agents and conduct master-slave inter-process communication), unless Azure is somehow tunneling MPI communication through inter-WorkerRole Azure Queues. ·        this is not the end of the story for Azure Grid Computing. If MS requires you to purchase a local HPC license (and administrate it), what's to stop a 3rd party from doing this and encapsulating exposing HPC WCF Broker Service to you for managing compute nodes? If MS doesn’t  provide head node as a service, someone else will! Process ·        requires creation of a worker node template that specifies a connection to an existing subscription for Windows Azure + an availability policy for the worker nodes. ·        After worker nodes are added to the cluster, you can start them, which provisions the Windows Azure role instances, and then bring them online to run HPC cluster jobs. ·        A Windows Azure worker role instance runs a HPC compatible Azure guest operating system which runs on the VMs that host your service. The guest operating system is updated monthly. You can choose to upgrade the guest OS for your service automatically each time an update is released - All role instances defined by your service will run on the guest operating system version that you specify. see Windows Azure Guest OS Releases and SDK Compatibility Matrix (http://go.microsoft.com/fwlink/?LinkId=190549). ·        use the hpcpack command to upload file packages and install files to run on the worker nodes. see hpcpack (http://go.microsoft.com/fwlink/?LinkID=205514). Requirements ·        assuming you have an azure subscription account and the HPC head node installed and configured. ·        Install HPC Pack 2008 R2 SP 1 -  see Microsoft HPC Pack 2008 R2 Service Pack 1 Release Notes (http://go.microsoft.com/fwlink/?LinkID=202812). ·        Configure the head node to connect to the Internet - connectivity is provided by the connection of the head node to the enterprise network. You may need to configure a proxy client on the head node. Any cluster network topology (1-5) is supported). ·        Configure the firewall - allow outbound TCP traffic on the following ports: 80,       443, 5901, 5902, 7998, 7999 ·        Note: HPC Server  uses Admin Mode (Elevated Privileges) in Windows Azure to give the service administrator of the subscription the necessary privileges to initialize HPC cluster services on the worker nodes. ·        Obtain a Windows Azure subscription certificate - the Windows Azure subscription must be configured with a public subscription (API) certificate -a valid X.509 certificate with a key size of at least 2048 bits. Generate a self-sign certificate & upload a .cer file to the Windows Azure Portal Account page > Manage my API Certificates link. see Using the Windows Azure Service Management API (http://go.microsoft.com/fwlink/?LinkId=205526). ·        import the certificate with an associated private key on the HPC cluster head node - into the trusted root store of the local computer account. Obtain Windows Azure Connection Information for HPC Server ·        required for each worker node template ·        copy from azure portal - Get from: navigation pane > Hosted Services > Storage Accounts & CDN ·        Subscription ID - a 32-char hex string in the form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. In Properties pane. ·        Subscription certificate thumbprint - a 40-char hex string (you need to remove spaces). In Management Certificates > Properties pane. ·        Service name - the value of <ServiceName> configured in the public URL of the service (http://<ServiceName>.cloudapp.net). In Hosted Services > Properties pane. ·        Blob Storage account name - the value of <StorageAccountName> configured in the public URL of the account (http://<StorageAccountName>.blob.core.windows.net). In Storage Accounts > Properties pane. Import the Azure Subscription Certificate on the HPC Head Node ·        enable the services for Windows HPC Server  to authenticate properly with the Windows Azure subscription. ·        use the Certificates MMC snap-in to import the certificate to the Trusted Root Certification Authorities store of the local computer account. The certificate must be in PFX format (.pfx or .p12 file) with a private key that is protected by a password. ·        see Certificates (http://go.microsoft.com/fwlink/?LinkId=163918). ·        To open the certificates snapin: Run > mmc. File > Add/Remove Snap-in > certificates > Computer account > Local Computer ·        To import the certificate via wizard - Certificates > Trusted Root Certification Authorities > Certificates > All Tasks > Import ·        After the certificate is imported, it appears in the details pane in the Certificates snap-in. You can open the certificate to check its status. Configure a Proxy Client on the HPC Head Node ·        the following Windows HPC Server services must be able to communicate over the Internet (through the firewall) with the services for Windows Azure: HPCManagement, HPCScheduler, HPCBrokerWorker. ·        Create a Windows Azure Worker Node Template ·        Edit HPC node templates in HPC Node Template Editor. ·        Specify: 1) Windows Azure subscription connection info (unique service name) for adding a set of worker nodes to the cluster + 2)worker node availability policy – rules for deploying / removing worker role instances in Windows Azure o   HPC Cluster Manager > Configuration > Navigation Pane > Node Templates > Actions pane > New à Create Node Template Wizard or Edit à Node Template Editor o   Choose Node Template Type page - Windows Azure worker node template o   Specify Template Name page – template name & description o   Provide Connection Information page – Azure Subscription ID (text) & Subscription certificate (browse) o   Provide Service Information page - Azure service name + blob storage account name (optionally click Retrieve Connection Information to get list of available from azure – possible LRT). o   Configure Azure Availability Policy page - how Windows Azure worker nodes start / stop (online / offline the worker role instance -  add / remove) – manual / automatic o   for automatic - In the Configure Windows Azure Worker Availability Policy dialog -select days and hours for worker nodes to start / stop. ·        To validate the Windows Azure connection information, on the template's Connection Information tab > Validate connection information. ·        You can upload a file package to the storage account that is specified in the template - eg upload application or service files that will run on the worker nodes. see hpcpack (http://go.microsoft.com/fwlink/?LinkID=205514). Add Azure Worker Nodes to the HPC Cluster ·        Use the Add Node Wizard – specify: 1) the worker node template, 2) The number of worker nodes   (within the quota of role instances in the azure subscription), and 3)           The VM size of the worker nodes : ExtraSmall, Small, Medium, Large, or ExtraLarge.  ·        to add worker nodes of different sizes, must run the Add Node Wizard separately for each size. ·        All worker nodes that are added to the cluster by using a specific worker node template define a set of worker nodes that will be deployed and managed together in Windows Azure when you start the nodes. This includes worker nodes that you add later by using the worker node template and, if you choose, worker nodes of different sizes. You cannot start, stop, or delete individual worker nodes. ·        To add Windows Azure worker nodes o   In HPC Cluster Manager: Node Management > Actions pane > Add Node à Add Node Wizard o   Select Deployment Method page - Add Azure Worker nodes o   Specify New Nodes page - select a worker node template, specify the number and size of the worker nodes ·        After you add worker nodes to the cluster, they are in the Not-Deployed state, and they have a health state of Unapproved. Before you can use the worker nodes to run jobs, you must start them and then bring them online. ·        Worker nodes are numbered consecutively in a naming series that begins with the root name AzureCN – this is non-configurable. Deploying Windows Azure Worker Nodes ·        To deploy the role instances in Windows Azure - start the worker nodes added to the HPC cluster and bring the nodes online so that they are available to run cluster jobs. This can be configured in the HPC Azure Worker Node Template – Azure Availability Policy -  to be automatic or manual. ·        The Start, Stop, and Delete actions take place on the set of worker nodes that are configured by a specific worker node template. You cannot perform one of these actions on a single worker node in a set. You also cannot perform a single action on two sets of worker nodes (specified by two different worker node templates). ·        ·          Starting a set of worker nodes deploys a set of worker role instances in Windows Azure, which can take some time to complete, depending on the number of worker nodes and the performance of Windows Azure. ·        To start worker nodes manually and bring them online o   In HPC Node Management > Navigation Pane > Nodes > List / Heat Map view - select one or more worker nodes. o   Actions pane > Start – in the Start Azure Worker Nodes dialog, select a node template. o   the state of the worker nodes changes from Not Deployed to track the provisioning progress – worker node Details Pane > Provisioning Log tab. o   If there were errors during the provisioning of one or more worker nodes, the state of those nodes is set to Unknown and the node health is set to Unapproved. To determine the reason for the failure, review the provisioning logs for the nodes. o   After a worker node starts successfully, the node state changes to Offline. To bring the nodes online, select the nodes that are in the Offline state > Bring Online. ·        Troubleshooting o   check node template. o   use telnet to test connectivity: telnet <ServiceName>.cloudapp.net 7999 o   check node status - Deployment status information appears in the service account information in the Windows Azure Portal - HPC queries this -  see  node status information for any failed nodes in HPC Node Management. ·        When role instances are deployed, file packages that were previously uploaded to the storage account using the hpcpack command are automatically installed. You can also upload file packages to storage after the worker nodes are started, and then manually install them on the worker nodes. see hpcpack (http://go.microsoft.com/fwlink/?LinkID=205514). ·        to remove a set of role instances in Windows Azure - stop the nodes by using HPC Cluster Manager (apply the Stop action). This deletes the role instances from the service and changes the state of the worker nodes in the HPC cluster to Not Deployed. ·        Each time that you start a set of worker nodes, two proxy role instances (size Small) are configured in Windows Azure to facilitate communication between HPC Cluster Manager and the worker nodes. The proxy role instances are not listed in HPC Cluster Manager after the worker nodes are added. However, the instances appear in the Windows Azure Portal. The proxy role instances incur charges in Windows Azure along with the worker node instances, and they count toward the quota of role instances in the subscription.

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  • The Proper Use of the VM Role in Windows Azure

    - by BuckWoody
    At the Professional Developer’s Conference (PDC) in 2010 we announced an addition to the Computational Roles in Windows Azure, called the VM Role. This new feature allows a great deal of control over the applications you write, but some have confused it with our full infrastructure offering in Windows Hyper-V. There is a proper architecture pattern for both of them. Virtualization Virtualization is the process of taking all of the hardware of a physical computer and replicating it in software alone. This means that a single computer can “host” or run several “virtual” computers. These virtual computers can run anywhere - including at a vendor’s location. Some companies refer to this as Cloud Computing since the hardware is operated and maintained elsewhere. IaaS The more detailed definition of this type of computing is called Infrastructure as a Service (Iaas) since it removes the need for you to maintain hardware at your organization. The operating system, drivers, and all the other software required to run an application are still under your control and your responsibility to license, patch, and scale. Microsoft has an offering in this space called Hyper-V, that runs on the Windows operating system. Combined with a hardware hosting vendor and the System Center software to create and deploy Virtual Machines (a process referred to as provisioning), you can create a Cloud environment with full control over all aspects of the machine, including multiple operating systems if you like. Hosting machines and provisioning them at your own buildings is sometimes called a Private Cloud, and hosting them somewhere else is often called a Public Cloud. State-ful and Stateless Programming This paradigm does not create a new, scalable way of computing. It simply moves the hardware away. The reason is that when you limit the Cloud efforts to a Virtual Machine, you are in effect limiting the computing resources to what that single system can provide. This is because much of the software developed in this environment maintains “state” - and that requires a little explanation. “State-ful programming” means that all parts of the computing environment stay connected to each other throughout a compute cycle. The system expects the memory, CPU, storage and network to remain in the same state from the beginning of the process to the end. You can think of this as a telephone conversation - you expect that the other person picks up the phone, listens to you, and talks back all in a single unit of time. In “Stateless” computing the system is designed to allow the different parts of the code to run independently of each other. You can think of this like an e-mail exchange. You compose an e-mail from your system (it has the state when you’re doing that) and then you walk away for a bit to make some coffee. A few minutes later you click the “send” button (the network has the state) and you go to a meeting. The server receives the message and stores it on a mail program’s database (the mail server has the state now) and continues working on other mail. Finally, the other party logs on to their mail client and reads the mail (the other user has the state) and responds to it and so on. These events might be separated by milliseconds or even days, but the system continues to operate. The entire process doesn’t maintain the state, each component does. This is the exact concept behind coding for Windows Azure. The stateless programming model allows amazing rates of scale, since the message (think of the e-mail) can be broken apart by multiple programs and worked on in parallel (like when the e-mail goes to hundreds of users), and only the order of re-assembling the work is important to consider. For the exact same reason, if the system makes copies of those running programs as Windows Azure does, you have built-in redundancy and recovery. It’s just built into the design. The Difference Between Infrastructure Designs and Platform Designs When you simply take a physical server running software and virtualize it either privately or publicly, you haven’t done anything to allow the code to scale or have recovery. That all has to be handled by adding more code and more Virtual Machines that have a slight lag in maintaining the running state of the system. Add more machines and you get more lag, so the scale is limited. This is the primary limitation with IaaS. It’s also not as easy to deploy these VM’s, and more importantly, you’re often charged on a longer basis to remove them. your agility in IaaS is more limited. Windows Azure is a Platform - meaning that you get objects you can code against. The code you write runs on multiple nodes with multiple copies, and it all works because of the magic of Stateless programming. you don’t worry, or even care, about what is running underneath. It could be Windows (and it is in fact a type of Windows Server), Linux, or anything else - but that' isn’t what you want to manage, monitor, maintain or license. You don’t want to deploy an operating system - you want to deploy an application. You want your code to run, and you don’t care how it does that. Another benefit to PaaS is that you can ask for hundreds or thousands of new nodes of computing power - there’s no provisioning, it just happens. And you can stop using them quicker - and the base code for your application does not have to change to make this happen. Windows Azure Roles and Their Use If you need your code to have a user interface, in Visual Studio you add a Web Role to your project, and if the code needs to do work that doesn’t involve a user interface you can add a Worker Role. They are just containers that act a certain way. I’ll provide more detail on those later. Note: That’s a general description, so it’s not entirely accurate, but it’s accurate enough for this discussion. So now we’re back to that VM Role. Because of the name, some have mistakenly thought that you can take a Virtual Machine running, say Linux, and deploy it to Windows Azure using this Role. But you can’t. That’s not what it is designed for at all. If you do need that kind of deployment, you should look into Hyper-V and System Center to create the Private or Public Infrastructure as a Service. What the VM Role is actually designed to do is to allow you to have a great deal of control over the system where your code will run. Let’s take an example. You’ve heard about Windows Azure, and Platform programming. You’re convinced it’s the right way to code. But you have a lot of things you’ve written in another way at your company. Re-writing all of your code to take advantage of Windows Azure will take a long time. Or perhaps you have a certain version of Apache Web Server that you need for your code to work. In both cases, you think you can (or already have) code the the software to be “Stateless”, you just need more control over the place where the code runs. That’s the place where a VM Role makes sense. Recap Virtualizing servers alone has limitations of scale, availability and recovery. Microsoft’s offering in this area is Hyper-V and System Center, not the VM Role. The VM Role is still used for running Stateless code, just like the Web and Worker Roles, with the exception that it allows you more control over the environment of where that code runs.

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  • Importing long numerical identifiers into Excel

    - by Niels Basjes
    I have some data in a database that uses ids that have the form of 16 digit numbers. In some situations i need to export the data in such a way that it can be manipulated in excel. So i export the data into a file and import it into excel. I've tried several file formats and I'm stuck. The problem I'm facing is that when reading a file into excel that has a cell that looks like a number then excel treats it as a number. The catch is that (as far as i can tell) all numerical values in excel are double precision floating point which have a precision of less than 16 digits. So my ids are changed: very often the last digit its changed to a 0. So far I've only been able to convince excel to keep the Id unchanged by breaking it myself: by adding a letter or symbol to the Id. This however means that in order to use the value again it must be "unbroken". Is there a way to create a file where i can specify that excel must treat the value as a text without changing the value? Or its there a way to let excel treat the value as a long (64bit integer)?

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