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• Book review: Microsoft System Center Enterprise Suite Unleashed

  - by BuckWoody

  I know, I know – what’s a database guy doing reading a book on System Center? Well, I need it from time to time. System Center is actually a collection of about 7 different products that you can use to manage and monitor your software and hardware, from drive space through Microsoft Office, UNIX systems, and yes, SQL Server. It’s that last part I care about the most, and so I’ve dealt with Data Protection Manager and System Center Operations Manager (I call it SCOM) in SQL Server. But I wasn’t familiar with the rest of the suite nor was I as familiar as I needed to be with the “Essentials” release – a separate product that groups together the main features of System Center into a single offering for smaller organizations. These companies usually run with a smaller IT shop, so they sometimes opt for this product to help them monitor everything, including SQL Server. So I picked up “Microsoft System Center Enterprise Suite Unleashed” by Chris Amaris and a cast of others. I don’t normally like to get a technical book by multiple authors – I just find that most of the time it’s quite jarring to switch from author to author, but I think this group did pretty well here.  The first chapter on introducing System Center has helped me talk with others about what the product does, and which pieces fit well together with SQL Server. The writing is well done, and I didn’t find a jump from author to author as I went along. The information is sequential, meaning that they lead you from install to configuration and then use. It’s very much a concepts-and-how-to book, and a big one at that – over 950 pages of learning! It was a pretty quick read, though, since I skipped the installation parts and there are lots of screenshots. While I’m not sure you’d be an expert on the product when you finish reading this book, but I would say you’re more than halfway there. I would say it suits someone that learns through examples the best, since they have a lot of step-by-step examples I do recommend that you take a look if you have to interact with this product, or even if you are a smaller shop and you’re the primary IT resource. The last few chapters deal with System Center Essentials, and honestly it was the best part of the book for me. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Silverlight Cream for May 04, 2010 -- #855

  - by Dave Campbell

  In this Issue: John Papa, Adam Kinney, Mike Taulty, Kirupa, Gunnar Peipman, Mike Snow(-2-, -3-), Jesse Liberty, and Lee. Shoutout: Jeff Wilcox announced Silverlight Unit Test Framework: New version in the April 2010 Silverlight Toolkit From SilverlightCream.com: Silverlight TV 23: MVP Q&A with WWW (Wildermuth, Wahlin and Ward) John Papa has Silverlight 23 up which is a panel discussion between Shawn Wildermuth, Dan Wahlin, Ward Bell and John... wow... what a crew! Design-time Resources in Expression Blend 4 RC Adam Kinney reports on the new feature of Expresseion Blend RC to load resources at design time. Adam also has a project available to demonstrate the concepts he's explaining. Silverlight and WCF RIA Services (1 - Overview) Mike Taulty is starting a series on WCF RIA Services. This first one is an overview and looks to be a good series as expected. Introduction to Sample Data - Page 1 Kirupa has a great 5-part post up about sample data in Expression Blend. Windows Phone 7 development: Using WebBrowser control Gunnar Peipman posted about using the web browser control in WP7 to display RSS data. Good stuff, and all the code too. Silverlight Tip of the Day #10 – Converting Client IP to Geographical Location Mike Snow's Tip #10 is about taking an IP address and getting a geographical location from it. Combine this with his Tip #9 that retrieves the IP address. Silverlight Tip of the Day #11 – Deploying Silverlight Applications with WCF web services. Mike Snow's Tip #11 is much bigger than most ... it's almost an end-to-end solution for creating and deploying a WCF service, including resolving problems. Silverlight Tip of the Day #12 – Getting an Images Source File Name Mike Snow also has tip #12 up, and it's a quick one on getting the original source file name for an image you've loaded. Screen Scraping – When All You Have Is A Hammer… Jesse Liberty posted his solution to a self-imposed problem and ended up writing a 'mini tutorial on using Silverlight for creating desk-top utilities' ... all with source. RIA services and combobox lookups Lee has a post up about RIA Services and setting up comboboxes for lookups. Lots of source in the post and full project download. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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• Inside Red Gate - Ricky Leeks

  - by Simon Cooper

  So, one of our profilers has a problem. Red Gate produces two .NET profilers - ANTS Performance Profiler (APP) and ANTS Memory Profiler (AMP). Both products help .NET developers solve problems they are virtually guaranteed to encounter at some point in their careers - slow code, and high memory usage, respectively. Everyone understands slow code - the symptoms are very obvious (an operation takes 2 hours when it should take 10 seconds), you know when you've solved it (the same operation now takes 15 seconds), and everyone understands how you can use a profiler like APP to help solve your particular problem. High memory usage is a much more subtle and misunderstood concept. How can .NET have memory leaks? The garbage collector, and how the CLR uses and frees memory, is one of the most misunderstood concepts in .NET. There's hundreds of blog posts out there covering various aspects of the GC and .NET memory, some of them helpful, some of them confusing, and some of them are just plain wrong. There's a lot of misconceptions out there. And, if you have got an application that uses far too much memory, it can be hard to wade through all the contradictory information available to even get an idea as to what's going on, let alone trying to solve it. That's where a memory profiler, like AMP, comes into play. Unfortunately, that's not the end of the issue. .NET memory management is a large, complicated, and misunderstood problem. Even armed with a profiler, you need to understand what .NET is doing with your objects, how it processes them, and how it frees them, to be able to use the profiler effectively to solve your particular problem. And that's what's wrong with AMP - even with all the thought, designs, UX sessions, and research we've put into AMP itself, some users simply don't have the knowledge required to be able to understand what AMP is telling them about how their application uses memory, and so they have problems understanding & solving their memory problem. Ricky Leeks This is where Ricky Leeks comes in. Created by one of the many...colourful...people in Red Gate, he headlines and promotes several tutorials, pages, and articles all with information on how .NET memory management actually works, with the goal to help educate developers on .NET memory management. And educating us all on how far you can push various vegetable-based puns. This, in turn, not only helps them understand and solve any memory issues they may be having, but helps them proactively code against such memory issues in their existing code. Ricky's latest outing is an interview on .NET Rocks, providing information on the Top 5 .NET Memory Management Gotchas, along with information on a free ebook on .NET Memory Management. Don't worry, there's loads more vegetable-based jokes where those came from...

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• Scripting Language Sessions at Oracle OpenWorld and MySQL Connect, 2012

  - by cj

  This posts highlights some great scripting language sessions coming up at the Oracle OpenWorld and MySQL Connect conferences. These events are happening in San Francisco from the end of September. You can search for other interesting conference sessions in the Content Catalog. Also check out what is happening at JavaOne in that event's Content Catalog (I haven't included sessions from it in this post.) To find the timeslots and locations of each session, click their respective link and check the "Session Schedule" box on the top right. GEN8431 - General Session: What’s New in Oracle Database Application Development This general session takes a look at what’s been new in the last year in Oracle Database application development tools using the latest generation of database technology. Topics range from Oracle SQL Developer and Oracle Application Express to Java and PHP. (Thomas Kyte - Architect, Oracle) BOF9858 - Meet the Developers of Database Access Services (OCI, ODBC, DRCP, PHP, Python) This session is your opportunity to meet in person the Oracle developers who have built Oracle Database access tools and products such as the Oracle Call Interface (OCI), Oracle C++ Call Interface (OCCI), and Open Database Connectivity (ODBC) drivers; Transparent Application Failover (TAF); Oracle Database Instant Client; Database Resident Connection Pool (DRCP); Oracle Net Services, and so on. The team also works with those who develop the PHP, Ruby, Python, and Perl adapters for Oracle Database. Come discuss with them the features you like, your pains, and new product enhancements in the latest database technology. CON8506 - Syndication and Consolidation: Oracle Database Driver for MySQL Applications This technical session presents a new Oracle Database driver that enables you to run MySQL applications (written in PHP, Perl, C, C++, and so on) against Oracle Database with almost no code change. Use cases for such a driver include application syndication such as interoperability across a relationship database management system, application migration, and database consolidation. In addition, the session covers enhancements in database technology that enable and simplify the migration of third-party databases and applications to and consolidation with Oracle Database. Attend this session to learn more and see a live demo. (Srinath Krishnaswamy - Director, Software Development, Oracle. Kuassi Mensah - Director Product Management, Oracle. Mohammad Lari - Principal Technical Staff, Oracle ) CON9167 - Current State of PHP and MySQL Together, PHP and MySQL power large parts of the Web. The developers of both technologies continue to enhance their software to ensure that developers can be satisfied despite all their changing and growing needs. This session presents an overview of changes in PHP 5.4, which was released earlier this year and shows you various new MySQL-related features available for PHP, from transparent client-side caching to direct support for scaling and high-availability needs. (Johannes Schlüter - SoftwareDeveloper, Oracle) CON8983 - Sharding with PHP and MySQL In deploying MySQL, scale-out techniques can be used to scale out reads, but for scaling out writes, other techniques have to be used. To distribute writes over a cluster, it is necessary to shard the database and store the shards on separate servers. This session provides a brief introduction to traditional MySQL scale-out techniques in preparation for a discussion on the different sharding techniques that can be used with MySQL server and how they can be implemented with PHP. You will learn about static and dynamic sharding schemes, their advantages and drawbacks, techniques for locating and moving shards, and techniques for resharding. (Mats Kindahl - Senior Principal Software Developer, Oracle) CON9268 - Developing Python Applications with MySQL Utilities and MySQL Connector/Python This session discusses MySQL Connector/Python and the MySQL Utilities component of MySQL Workbench and explains how to write MySQL applications in Python. It includes in-depth explanations of the features of MySQL Connector/Python and the MySQL Utilities library, along with example code to illustrate the concepts. Those interested in learning how to expand or build their own utilities and connector features will benefit from the tips and tricks from the experts. This session also provides an opportunity to meet directly with the engineers and provide feedback on your issues and priorities. You can learn what exists today and influence future developments. (Geert Vanderkelen - Software Developer, Oracle) BOF9141 - MySQL Utilities and MySQL Connector/Python: Python Developers, Unite! Come to this lively discussion of the MySQL Utilities component of MySQL Workbench and MySQL Connector/Python. It includes in-depth explanations of the features and dives into the code for those interested in learning how to expand or build their own utilities and connector features. This is an audience-driven session, so put on your best Python shirt and let’s talk about MySQL Utilities and MySQL Connector/Python. (Geert Vanderkelen - Software Developer, Oracle. Charles Bell - Senior Software Developer, Oracle) CON3290 - Integrating Oracle Database with a Social Network Facebook, Flickr, YouTube, Google Maps. There are many social network sites, each with their own APIs for sharing data with them. Most developers do not realize that Oracle Database has base tools for communicating with these sites, enabling all manner of information, including multimedia, to be passed back and forth between the sites. This technical presentation goes through the methods in PL/SQL for connecting to, and then sending and retrieving, all types of data between these sites. (Marcelle Kratochvil - CTO, Piction) CON3291 - Storing and Tuning Unstructured Data and Multimedia in Oracle Database Database administrators need to learn new skills and techniques when the decision is made in their organization to let Oracle Database manage its unstructured data. They will face new scalability challenges. A single row in a table can become larger than a whole database. This presentation covers the techniques a DBA needs for managing the large volume of data in a standard Oracle Database instance. (Marcelle Kratochvil - CTO, Piction) CON3292 - Using PHP, Perl, Visual Basic, Ruby, and Python for Multimedia in Oracle Database These five programming languages are just some of the most popular ones in use at the moment in the marketplace. This presentation details how you can use them to access and retrieve multimedia from Oracle Database. It covers programming techniques and methods for achieving faster development against Oracle Database. (Marcelle Kratochvil - CTO, Piction) UGF5181 - Building Real-World Oracle DBA Tools in Perl Perl is not normally associated with building mission-critical application or DBA tools. Learn why Perl could be a good choice for building your next killer DBA app. This session draws on real-world experience of building DBA tools in Perl, showing the framework and architecture needed to deal with portability, efficiency, and maintainability. Topics include Perl frameworks; Which Comprehensive Perl Archive Network (CPAN) modules are good to use; Perl and CPAN module licensing; Perl and Oracle connectivity; Compiling and deploying your app; An example of what is possible with Perl. (Arjen Visser - CEO & CTO, Dbvisit Software Limited) CON3153 - Perl: A DBA’s and Developer’s Best (Forgotten) Friend This session reintroduces Perl as a language of choice for many solutions for DBAs and developers. Discover what makes Perl so successful and why it is so versatile in our day-to-day lives. Perl can automate all those manual tasks and is truly platform-independent. Perl may not be in the limelight the way other languages are, but it is a remarkable language, it is still very current with ongoing development, and it has amazing online resources. Learn what makes Perl so great (including CPAN), get an introduction to Perl language syntax, find out what you can use Perl for, hear how Oracle uses Perl, discover the best way to learn Perl, and take away a small Perl project challenge. (Arjen Visser - CEO & CTO, Dbvisit Software Limited) CON10332 - Oracle RightNow CX Cloud Service’s Connect PHP API: Intro, What’s New, and Roadmap Connect PHP is a public API that enables developers to build solutions with the Oracle RightNow CX Cloud Service platform. This API is used primarily by developers working within the Oracle RightNow Customer Portal Cloud Service framework who are looking to gain access to data and services hosted by the Oracle RightNow CX Cloud Service platform through a backward-compatible API. Connect for PHP leverages the same data model and services as the Connect Web Services for SOAP API. Come to this session to get an introduction and learn what’s new and what’s coming up. (Mark Rhoads - Senior Principal Applications Engineer, Oracle. Mark Ericson - Sr. Principle Product Manager, Oracle) CON10330 - Oracle RightNow CX Cloud Service APIs and Frameworks Overview Oracle RightNow CX Cloud Service APIs are available in the following areas: desktop UI, Web services, customer portal, PHP, and knowledge. These frameworks provide access to Oracle RightNow CX Cloud Service’s Connect Common Object Model and custom objects. This session provides a broad overview of capabilities in all these areas. (Mark Ericson - Sr. Principle Product Manager, Oracle)

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• Looking into ASP.Net MVC 4.0 Mobile Development - part 2

  - by nikolaosk

  In this post I will be continuing my discussion on ASP.Net MVC 4.0 mobile development. You can have a look at my first post on the subject here . Make sure you read it and understand it well before you move one reading the remaining of this post. I will not be writing any code in this post. I will try to explain a few concepts related to the MVC 4.0 mobile functionality. In this post I will be looking into the Browser Overriding feature in ASP.Net MVC 4.0. By that I mean that we override the user agent for a given user session. This is very useful feature for people who visit a site through a device and they experience the mobile version of the site, but what they really want is the option to be able to switch to the desktop view. "Why they might want to do that?", you might wonder.Well first of all the users of our ASP.Net MVC 4.0 application will appreciate that they have the option to switch views while some others will think that they will enjoy more the contents of our website with the "desktop view" since the mobile device they view our site has a quite large display.  Obviously this is only one site. These are just different views that are rendered.To put it simply, browser overriding lets our application treat requests as if they were coming from a different browser rather than the one they are actually from. In order to do that programmatically we must have a look at the System.Web.WebPages namespace and the classes in it. Most specifically the class BrowserHelpers. Have a look at the picture below   In this class we see some extension methods for HttpContext class.These methods are called extensions-helpers methods and we use them to switch to one browser from another thus overriding the current/actual browser. These APIs have effect on layout,views and partial views and will not affect any other ASP.Net Request.Browser related functionality.The overridden browser is stored in a cookie. Let me explain what some of these methods do. SetOverriddenBrowser() -  let us set the user agent string to specific value GetOverriddenBrowser() -  let us get the overridden value ClearOverriddenBrowser() -  let us remove any overridden user agent for the current request   To recap, in our ASP.Net MVC 4.0 applications when our application is viewed in our mobile devices, we can have a link like "Desktop View" for all those who desperately want to see the site with in full desktop-browser version.We then can specify a browser type override. My controller class (snippet of code) that is responsible for handling the switching could be something like that. public class SwitchViewController : Controller{ public RedirectResult SwitchView(bool mobile, string returnUrl){if (Request.Browser.IsMobileDevice == mobile)HttpContext.ClearOverriddenBrowser();elseHttpContext.SetOverriddenBrowser(mobile ? BrowserOverride.Mobile : BrowserOverride.Desktop);return Redirect(returnUrl);}} Hope it helps!!!!

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• Introduction to Lean Software Development and Kanban Systems

  - by Ben Griswold

  Last year I took myself through a crash course on Lean Software Development and Kanban Systems in preparation for an in-house presentation.  I learned a bunch.  In this series, I’ll be sharing what I learned with you.   If your career looks anything like mine, you have probably been affiliated with a company or two which pushed requirements gathering and documentation to the nth degree. To add insult to injury, they probably added planning process (documentation, requirements, policies, meetings, committees) to the extent that it possibly retarded any progress. In my opinion, the typical company resembles the quote from Tom DeMarco. It isn’t enough just to do things right – we also had to say in advance exactly what we intended to do and then do exactly that. In the 1980s, Toyota turned the tables and revolutionize the automobile industry with their approach of “Lean Manufacturing.” A massive paradigm shift hit factories throughout the US and Europe. Mass production and scientific management techniques from the early 1900’s were questioned as Japanese manufacturing companies demonstrated that ‘Just-in-Time’ was a better paradigm. The widely adopted Japanese manufacturing concepts came to be known as ‘lean production’. Lean Thinking capitalizes on the intelligence of frontline workers, believing that they are the ones who should determine and continually improve the way they do their jobs. Lean puts main focus on people and communication – if people who produce the software are respected and they communicate efficiently, it is more likely that they will deliver good product and the final customer will be satisfied. In time, the abstractions behind lean production spread to logistics, and from there to the military, to construction, and to the service industry. As it turns out, principles of lean thinking are universal and have been applied successfully across many disciplines. Lean has been adopted by companies including Dell, FedEx, Lens Crafters, LLBean, SW Airlines, Digital River and eBay. Lean thinking got its name from a 1990’s best seller called The Machine That Changed the World : The Story of Lean Production. This book chronicles the movement of automobile manufacturing from craft production to mass production to lean production. Tom and Mary Poppendieck, that is.  Here’s one of their books: Implementing Lean Software Thinking: From Concept to Cash Our in-house presentations are supposed to run no more than 45 minutes.  I really cranked and got through my 87 slides in just under an hour. Of course, I had to cheat a little – I only covered the 7 principles and a single practice. In the next part of the series, we’ll dive into Principle #1: Eliminate Waste. And I am going to be a little obnoxious about listing my Lean and Kanban references with every series post.  The references are great and they deserve this sort of attention. 

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• How to become a solid python web developer [closed]

  - by Estarius

  Possible Duplicate: How do I learn Python from zero to web development? I have started Python recently with the goal to become a solid developer to make a web application eventually. However, as time goes by I am wondering if I am being optimal about how I will achieve my goal. I would compare it to a game for example, to be better you must spend time playing and trying new things... However, if you just log in and sit in the lobby chatting you are most likely not progressing. So far, this is my plan (feel free to comment or judge it): Review basic programmation concepts Start coding slowly in Python Once comfortable in Python, learn about web development in Python Learn about those things we heard about: SQLAlchemy, MVC, TDD, Git, Agile (Group project) To achieve these things, I started the Learn python the hard way exercises, which I am doing at the rate of 5 per days. I also started to read Think Python at the same time and planning to move on with Dive into python. As far as my research goes, these documentations along with Python documentation is usually what is the most recommended to learn Python. I consider this to get my point 1 and 2 done. While learning Python is really great, my goal remains to do quality web development. I know there are books about Django etc. however I would like to become comfortable with any Python web development. This means without Framework and with Framework... Any framework, then be able to choose the one which best fits our needs. For this I would like to know if some people have suggestions. Should I just get a book on Django and it should apply to everything ? What would be the best method to go from Python to Web Python and not end up creating crappy code which would turn into nightmares for other programmers ? Then finally, those "things we hear about". While I understand what they all do basically, I am fairly sure that like everything, there are good and wrong ways of making use of them. Should I go through at least a whole book on each before starting to use them or keep it at their respective online documentation ? Are there some kind of documentation which links their use to Python ? Also, from looking at Django and Pyramid they seems to use something else than MVC, while the Django model looks similar, the Pyramid one seems to cut a whole part of it... Is learning MVC still worth it ? Sorry for the wall of text, Thanks in advance !

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• SQLAuthority News – Weekend Experiment with NuoDB – Points to Pondor and Whitepaper

  - by pinaldave

  This weekend I have downloaded the latest beta version of NuoDB. I found it much improved and better UI. I was very much impressed as the installation was very smooth and I was up and running in less than 5 minutes with the product. The tools which are related to the Administration of the NuoDB seems to get makeover during this beta release. As per the claim they support now Solaris platform and have improved the native MacOS installation. I neither have Mac nor Solaris – I wish I would have experimented with the same. I will appreciate if anyone out there can confirm how the installations goes on these platforms. I have previously blogged about my experiment with NuoDB here: SQL SERVER – Weekend Project – Experimenting with ACID Transactions, SQL Compliant, Elastically Scalable Database SQL SERVER – Beginning NuoDB – Who will Benefit and How to Start SQL SERVER – Follow up on Beginning NuoDB – Who will Benefit and How to Start – Part 2 I am very impressed with the product so far and I have decided to understand the product further deep. Here are few of the questions which I am going to try to find answers with regards to NuoDB. Just so it is clear – NuoDB is not NOSQL, matter of the fact, it is following all the ACID properties of the database. If ACID properties are crucial why many NoSQL products are not adhering to it? (There are few out there do follow ACID but not all). I do understand the scalability of the database however does elasticity is crucial for the database and if yes how? (Elasticity is where the workload on the database is heavily fluctuating and the need of more than a single database server is coming up). How NuoDB has built scalable, elastic and 100% ACID compliance database which supports multiple platforms? How is NOSQL compared to NuoDB’s new architecture? In the next coming weeks, I am going to explore above concepts and dive deeper into the understanding of the same. Meanwhile I have read following white paper written by Experts at University of California at Santa Barbara. Very interesting read and great starter on the subject Database Scalability, Elasticity, and Autonomy in the Cloud. Additionally, my questions are also talking about NoSQL, this weekend I have started to learn about NoSQL from Pluralsight‘s online learning library. I will share my experience very soon. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL White Papers, T SQL, Technology Tagged: NuoDB

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• C# Domain-Driven Design Sample Released

  - by Artur Trosin

  In the post I want to declare that NDDD Sample application(s) is released and share the work with you. You can access it here: http://code.google.com/p/ndddsample. NDDDSample from functionality perspective matches DDDSample 1.1.0 which is based Java and on joint effort by Eric Evans' company Domain Language and the Swedish software consulting company Citerus. But because NDDDSample is based on .NET technologies those two implementations could not be matched directly. However concepts, practices, values, patterns, especially DDD, are cross-language and cross-platform :). Implementation of .NET version of the application was an interesting journey because now as .NET developer I better understand the differences positive and negative between these two platforms. Even there are those differences they can be overtaken, in many cases it was not so hard to match a java libs\framework with .NET during the implementation. Here is a list of technology stack: 1. .net 3.5 - framework 2. VS.NET 2008 - IDE 3. ASP.NET MVC2.0 - for administration and tracking UI 4. WCF - communication mechanism 5. NHibernate - ORM 6. Rhino Commons - Nhibernate session management, base classes for in memory unit tests 7. SqlLite - database 8. Windsor - inversion of control container 9. Windsor WCF facility - for better integration with NHibernate 10. MvcContrib - and in particular its Castle WindsorControllerFactory in order to enable IoC for controllers 11. WPF - for incident logging application 12. Moq - mocking lib used for unit tests 13. NUnit - unit testing framework 14. Log4net - logging framework 15. Cloud based on Azure SDK These are not the latest technologies, tools and libs for the moment but if there are someone thinks that it would be useful to migrate the sample to latest current technologies and versions please comment. Cloud version of the application is based on Azure emulated environment provided by the SDK, so it hasn't been tested on ‘real' Azure scenario (we just do not have access to it). Thanks to participants, Eugen Gorgan who was involved directly in development, Ruslan Rusu and Victor Lungu spend their free time to discuss .NET specific decisions, Eugen Navitaniuc helped with Java related questions. Also, big thank to Cornel Cretu, he designed a nice logo and helped with some browser incompatibility issues. Any review and feedback are welcome! Thank you, Artur Trosin

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• Freshen the RTS genre

  - by William Michael Thorley

  This isn't really a question, but a request for feedback. RPS (Rock, Paper, Scissors) RTS (Real Time Strategy) Demo version is out: The game is simple. It is an RTS. Why has it been made? Many if not most RTS’s are about economy and large numbers of unit types. The genre hasn’t actually developed the gameplay drastically from the very first RTS’s produced, some lesson have been learned, but the games are really very similar to how they have always been. RPS brings new gameplay to the RTS genre. Through three means: • New combat mechanics: RPS has two unique modes (as well as the old favourite) of resolving weapon fire. These change how combat happens, and make application of the correct units vital to success. From this comes the requirement to run Intel on your enemies. • Fixed Resource Economy: Each player has a fixed amount of energy, This means that there is a definite end to the game. You can attrition your enemy and try to outlast them, or try to outspend your opponent and destroy them. There is a limit to how fast ships can be built, through the generation of construction blocks, but energy is the fast limit on economy. • Game Modes: Game modes add victory conditions and new game pieces. The game is overseen by a controller which literally runs the game. Games are no longer line them up, gun them down. This means that new tactics must be played making skirmish games fresh with novel tactics without adding huge amounts of new game units to learn. I’ve produced RPS from the ground. I will be running a kickstarter in the near future, but right now I want feedback and input from the game developing community. Regarding the concepts, where RPS is going, the game modes, the combat mechanics. How it plays. RPS will give fresh gameplay to the genre so it must be right. It works over the internet or a LAN and supports single player games. Get it. Play it. Tell me about your games. Thank you Demo: https://dl.dropbox.com/u/51850113/RPS%20Playtest.zip Tutorials: https://dl.dropbox.com/u/51850113/RPSGamePlay.zip

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• Personal Development : Time, Planning , Repairs & Maintenance

  - by Rajesh Pillai

  Personal Development : Time, Planning, Repairs & Maintenance These are just my thoughts, but some you may find something interesting in it. Please think over it. We may know many things, but still we always keeps procrastinating it. I have written this as I have heard many people coming back and saying they don’t have time to do things they like. These are my thoughts buy may be useful to someone else too. Certain things in life needs periodic repairs and maintenance. To cite some examples , your CAR, your HOUSE, your personal laptop/desktop, your health etc. Likewise there are certain other things in professional life that requires repair/ maintenance /or some kind of polishing, so that you always stay on top of it. But they are not always obvious. Some of them are - Improving your communication skills - Increasing your vocabulary - Upgrading your technical skills - Pursuing your hobby - Increasing your knowledge/awareness etc… etc… And then there are certain things that we are always short of…. one is TIME. We all know TIME is one of the most precious things in life and yet we all are very miserable at managing it. Remember you can only manage it and not control it. You can only control which you own or which you create. In theory time is infinite. So, there should be abundant of it. But remember one thing, you know this, it’s not reversible. Once it has elapsed you cannot live it again. Think over it. So, how do find that golden 25th hour every day. To find the 25th hour you need to reflect back on your current daily activities. Analyze them and see where you are spending most of your time and is it really important. Even the 8 hours that you spent in the office, is it spent fruitfully. At the end of the day is the 8 precious hour that you spent was worth it. Just reflect back on your activities. Did you learn something? If yes did you make a point to NOTE IT. If you didn’t NOTED it then was the time you spent really worth it. Just ponder over it. Some calculations of your daily activities where most of the time is spent. Let’s start (in no particular order though) - Sleep (6.5 hours) [Remember you only require 6 good hours of sleep every day]. Some may thing it is 8, but it’s a myth.   o To achive 6 hours of sleep and be in good health you can practice 15 minutes of daily meditation. So effectively you can    round it to 6.5 hours. - Morning chores(2 hours) : Some may need to prepare breakfast and all other things. - Office commuting (avg. to and fro 3 hours) - Office Work (avg 9.5 hours) Total Hours: 21 hours effective time which is spent irrespective of what you do. There may be some variations here and there. Still you have 3 hours EXTRA. Where do these 3 hours go? If you can find it, then you may get that golden 25th hour out of these 3 hours. Let’s discount 2 hours for contingencies, still you have 1 hour with you. If you can’t find it then you are living a direction less life. As you can see, the 25th Hour lies within the 24 hours of the day. It’s upto each one of us to find and make use of it. Now what can you do with that 25th hour i.e. 1 hour extra of your life. Imagine the possibility. Again some calculations 1 hour daily * 30 days = 30 hours every month 30 hours pm * 12 month = 360 hours every year. 360 hours every year seems very promising. Let’s add some contingencies, say, let’s be optimistic and say 50 % contingency. Still you have 180 hours every year. That leaves with 30 minutes every day of extra time. That’s hell a lot of time, if you could manage it. These may sound like a high talk [yes, it is, unless you apply these simple rules and rationalize your everyday living and stop procrastinating]. NOTE: I haven’t taken weekend, holidays and leaves into account. So, that leaves us with a lot of buffer time. You can meet family friends, relatives, other tasks, and yet have these 180 pure hours of joy every year. Do whatever you want to do with it. So, how important is this 180 hours per year to you? Just think over it. You may use it the way you like - 50 hours [pursue your hobby like drawing, crafting, learn dance, learn juggling, learn swimming, travelling hmm.. anything you like doing and you didn’t had time to do it.] - 30 hours you can learn a new programming language or technology (i.e. you can get comfortable with it) - 50 hours [improve existing skills] - 20 hours [improve you communication skill]. Do some light reading. - 30 hours [YOU DECIDE WHAT TO DO]? So, if you had done this for one year you would have learnt a new programming language, upgraded existing skills, improved you communication etc.. If you had done this for two years.. imagine the level of personal development or growth which you may have attained….. If you had done this for three years….. NOW I think I don’t need to mention this… So, you still have TIME, as they say TIME is infinite. So, make judicious use of this precious thing. And never ever comeback saying “I don’t have time”. So, if you are RICH in TIME, everything else will be automatically taken care of, as those things may just be a byproduct of how you spend your time… So, happy TIMING your TIME everyday.

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• BigData and Customer Experience: Happy Together

  - by Isabel F. Peñuelas

  The two big buzzes of the year may lay closer than it appears. Both concepts intersect at various points: BigData and Return of Investment of Marketing Campaigns On a recent post Big Data Is The Future Of Marketing Jeff Dachis explains very clearly how “Big data analytics finally allows marketers to identify, measure, and manage what is positively impacting their Brand”. Regression analysis applied to big data volumes coming from social media will substitute the failed attempts to justify marketing investments on social media in terms of followers and likes, he continues, “the measurement models applied by marketers on TV Campaigns don´t work on social”, we need to study the data with fresh eyes and maybe then we will start understanding and measuring brand engagemet. Social CRM and BigData The real value of Social CRM start by analyzing mass of big data from social media in order of applying social intelligence techniques that allow us to classify new customer niches and communities and define appropriated strategies to contact potential customers. Gartner Says that the Market for Social CRM is on pace to surpass $1 Billion in Revenue by Year-End 2012 but in words of Zach Hofer-Shall, Analyst at Forrester Research “Social customer relationship management is hard” (The Social CRM Arms Race Heats ). To succeed brands need three things: Investing in new social tools, investing in consultancy and investing in infrastructure for massive data storage and analysis. Neither CeX or BigData are easy and cheap wins. But what are the customer benefits of such investments? Big Data and Brand Engagement Time is the most valuable asset of todays consumers: tired of information overload, exhausted by the terabytes of offering, anxious because of not having the same fast multichannel experience with their services’ marketers or preferred goods providers than the one they found on their social media. Yes, I know you have read this before- me too. But is real. The motto of the Customer Experience philosophy of providing a consistent experience through multiple touchpoints that makes the relationship customer/brand easier and valuable finds it basis on understanding customer/s preferences and context for which BigData analysis is another imperative. In summary, I believe that using BigData Analysis in combination with appropriated CeX strategies and technologies is a promising direction for achieving: efficiency and marketing cost-savings; growing the customer base; and increasing customer conversion and retention. In a world: The Direction of Future Marketing.

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• C# Performance Pitfall – Interop Scenarios Change the Rules

  - by Reed

  C# and .NET, overall, really do have fantastic performance in my opinion.  That being said, the performance characteristics dramatically differ from native programming, and take some relearning if you’re used to doing performance optimization in most other languages, especially C, C++, and similar.  However, there are times when revisiting tricks learned in native code play a critical role in performance optimization in C#. I recently ran across a nasty scenario that illustrated to me how dangerous following any fixed rules for optimization can be… The rules in C# when optimizing code are very different than C or C++.  Often, they’re exactly backwards.  For example, in C and C++, lifting a variable out of loops in order to avoid memory allocations often can have huge advantages.  If some function within a call graph is allocating memory dynamically, and that gets called in a loop, it can dramatically slow down a routine. This can be a tricky bottleneck to track down, even with a profiler.  Looking at the memory allocation graph is usually the key for spotting this routine, as it’s often “hidden” deep in call graph.  For example, while optimizing some of my scientific routines, I ran into a situation where I had a loop similar to: for (i=0; i<numberToProcess; ++i) { // Do some work ProcessElement(element[i]); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This loop was at a fairly high level in the call graph, and often could take many hours to complete, depending on the input data.  As such, any performance optimization we could achieve would be greatly appreciated by our users. After a fair bit of profiling, I noticed that a couple of function calls down the call graph (inside of ProcessElement), there was some code that effectively was doing: // Allocate some data required DataStructure* data = new DataStructure(num); // Call into a subroutine that passed around and manipulated this data highly CallSubroutine(data); // Read and use some values from here double values = data->Foo; // Cleanup delete data; // ... return bar; Normally, if “DataStructure” was a simple data type, I could just allocate it on the stack.  However, it’s constructor, internally, allocated it’s own memory using new, so this wouldn’t eliminate the problem.  In this case, however, I could change the call signatures to allow the pointer to the data structure to be passed into ProcessElement and through the call graph, allowing the inner routine to reuse the same “data” memory instead of allocating.  At the highest level, my code effectively changed to something like: DataStructure* data = new DataStructure(numberToProcess); for (i=0; i<numberToProcess; ++i) { // Do some work ProcessElement(element[i], data); } delete data; Granted, this dramatically reduced the maintainability of the code, so it wasn’t something I wanted to do unless there was a significant benefit.  In this case, after profiling the new version, I found that it increased the overall performance dramatically – my main test case went from 35 minutes runtime down to 21 minutes.  This was such a significant improvement, I felt it was worth the reduction in maintainability. In C and C++, it’s generally a good idea (for performance) to: Reduce the number of memory allocations as much as possible, Use fewer, larger memory allocations instead of many smaller ones, and Allocate as high up the call stack as possible, and reuse memory I’ve seen many people try to make similar optimizations in C# code.  For good or bad, this is typically not a good idea.  The garbage collector in .NET completely changes the rules here. In C#, reallocating memory in a loop is not always a bad idea.  In this scenario, for example, I may have been much better off leaving the original code alone.  The reason for this is the garbage collector.  The GC in .NET is incredibly effective, and leaving the allocation deep inside the call stack has some huge advantages.  First and foremost, it tends to make the code more maintainable – passing around object references tends to couple the methods together more than necessary, and overall increase the complexity of the code.  This is something that should be avoided unless there is a significant reason.  Second, (unlike C and C++) memory allocation of a single object in C# is normally cheap and fast.  Finally, and most critically, there is a large advantage to having short lived objects.  If you lift a variable out of the loop and reuse the memory, its much more likely that object will get promoted to Gen1 (or worse, Gen2).  This can cause expensive compaction operations to be required, and also lead to (at least temporary) memory fragmentation as well as more costly collections later. As such, I’ve found that it’s often (though not always) faster to leave memory allocations where you’d naturally place them – deep inside of the call graph, inside of the loops.  This causes the objects to stay very short lived, which in turn increases the efficiency of the garbage collector, and can dramatically improve the overall performance of the routine as a whole. In C#, I tend to: Keep variable declarations in the tightest scope possible Declare and allocate objects at usage While this tends to cause some of the same goals (reducing unnecessary allocations, etc), the goal here is a bit different – it’s about keeping the objects rooted for as little time as possible in order to (attempt) to keep them completely in Gen0, or worst case, Gen1.  It also has the huge advantage of keeping the code very maintainable – objects are used and “released” as soon as possible, which keeps the code very clean.  It does, however, often have the side effect of causing more allocations to occur, but keeping the objects rooted for a much shorter time. Now – nowhere here am I suggesting that these rules are hard, fast rules that are always true.  That being said, my time spent optimizing over the years encourages me to naturally write code that follows the above guidelines, then profile and adjust as necessary.  In my current project, however, I ran across one of those nasty little pitfalls that’s something to keep in mind – interop changes the rules. In this case, I was dealing with an API that, internally, used some COM objects.  In this case, these COM objects were leading to native allocations (most likely C++) occurring in a loop deep in my call graph.  Even though I was writing nice, clean managed code, the normal managed code rules for performance no longer apply.  After profiling to find the bottleneck in my code, I realized that my inner loop, a innocuous looking block of C# code, was effectively causing a set of native memory allocations in every iteration.  This required going back to a “native programming” mindset for optimization.  Lifting these variables and reusing them took a 1:10 routine down to 0:20 – again, a very worthwhile improvement. Overall, the lessons here are: Always profile if you suspect a performance problem – don’t assume any rule is correct, or any code is efficient just because it looks like it should be Remember to check memory allocations when profiling, not just CPU cycles Interop scenarios often cause managed code to act very differently than “normal” managed code. Native code can be hidden very cleverly inside of managed wrappers

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• Fraud Detection with the SQL Server Suite Part 2

  - by Dejan Sarka

  This is the second part of the fraud detection whitepaper. You can find the first part in my previous blog post about this topic. My Approach to Data Mining Projects It is impossible to evaluate the time and money needed for a complete fraud detection infrastructure in advance. Personally, I do not know the customer’s data in advance. I don’t know whether there is already an existing infrastructure, like a data warehouse, in place, or whether we would need to build one from scratch. Therefore, I always suggest to start with a proof-of-concept (POC) project. A POC takes something between 5 and 10 working days, and involves personnel from the customer’s site – either employees or outsourced consultants. The team should include a subject matter expert (SME) and at least one information technology (IT) expert. The SME must be familiar with both the domain in question as well as the meaning of data at hand, while the IT expert should be familiar with the structure of data, how to access it, and have some programming (preferably Transact-SQL) knowledge. With more than one IT expert the most time consuming work, namely data preparation and overview, can be completed sooner. I assume that the relevant data is already extracted and available at the very beginning of the POC project. If a customer wants to have their people involved in the project directly and requests the transfer of knowledge, the project begins with training. I strongly advise this approach as it offers the establishment of a common background for all people involved, the understanding of how the algorithms work and the understanding of how the results should be interpreted, a way of becoming familiar with the SQL Server suite, and more. Once the data has been extracted, the customer’s SME (i.e. the analyst), and the IT expert assigned to the project will learn how to prepare the data in an efficient manner. Together with me, knowledge and expertise allow us to focus immediately on the most interesting attributes and identify any additional, calculated, ones soon after. By employing our programming knowledge, we can, for example, prepare tens of derived variables, detect outliers, identify the relationships between pairs of input variables, and more, in only two or three days, depending on the quantity and the quality of input data. I favor the customer’s decision of assigning additional personnel to the project. For example, I actually prefer to work with two teams simultaneously. I demonstrate and explain the subject matter by applying techniques directly on the data managed by each team, and then both teams continue to work on the data overview and data preparation under our supervision. I explain to the teams what kind of results we expect, the reasons why they are needed, and how to achieve them. Afterwards we review and explain the results, and continue with new instructions, until we resolve all known problems. Simultaneously with the data preparation the data overview is performed. The logic behind this task is the same – again I show to the teams involved the expected results, how to achieve them and what they mean. This is also done in multiple cycles as is the case with data preparation, because, quite frankly, both tasks are completely interleaved. A specific objective of the data overview is of principal importance – it is represented by a simple star schema and a simple OLAP cube that will first of all simplify data discovery and interpretation of the results, and will also prove useful in the following tasks. The presence of the customer’s SME is the key to resolving possible issues with the actual meaning of the data. We can always replace the IT part of the team with another database developer; however, we cannot conduct this kind of a project without the customer’s SME. After the data preparation and when the data overview is available, we begin the scientific part of the project. I assist the team in developing a variety of models, and in interpreting the results. The results are presented graphically, in an intuitive way. While it is possible to interpret the results on the fly, a much more appropriate alternative is possible if the initial training was also performed, because it allows the customer’s personnel to interpret the results by themselves, with only some guidance from me. The models are evaluated immediately by using several different techniques. One of the techniques includes evaluation over time, where we use an OLAP cube. After evaluating the models, we select the most appropriate model to be deployed for a production test; this allows the team to understand the deployment process. There are many possibilities of deploying data mining models into production; at the POC stage, we select the one that can be completed quickly. Typically, this means that we add the mining model as an additional dimension to an existing DW or OLAP cube, or to the OLAP cube developed during the data overview phase. Finally, we spend some time presenting the results of the POC project to the stakeholders and managers. Even from a POC, the customer will receive lots of benefits, all at the sole risk of spending money and time for a single 5 to 10 day project: The customer learns the basic patterns of frauds and fraud detection The customer learns how to do the entire cycle with their own people, only relying on me for the most complex problems The customer’s analysts learn how to perform much more in-depth analyses than they ever thought possible The customer’s IT experts learn how to perform data extraction and preparation much more efficiently than they did before All of the attendees of this training learn how to use their own creativity to implement further improvements of the process and procedures, even after the solution has been deployed to production The POC output for a smaller company or for a subsidiary of a larger company can actually be considered a finished, production-ready solution It is possible to utilize the results of the POC project at subsidiary level, as a finished POC project for the entire enterprise Typically, the project results in several important “side effects” Improved data quality Improved employee job satisfaction, as they are able to proactively contribute to the central knowledge about fraud patterns in the organization Because eventually more minds get to be involved in the enterprise, the company should expect more and better fraud detection patterns After the POC project is completed as described above, the actual project would not need months of engagement from my side. This is possible due to our preference to transfer the knowledge onto the customer’s employees: typically, the customer will use the results of the POC project for some time, and only engage me again to complete the project, or to ask for additional expertise if the complexity of the problem increases significantly. I usually expect to perform the following tasks: Establish the final infrastructure to measure the efficiency of the deployed models Deploy the models in additional scenarios Through reports By including Data Mining Extensions (DMX) queries in OLTP applications to support real-time early warnings Include data mining models as dimensions in OLAP cubes, if this was not done already during the POC project Create smart ETL applications that divert suspicious data for immediate or later inspection I would also offer to investigate how the outcome could be transferred automatically to the central system; for instance, if the POC project was performed in a subsidiary whereas a central system is available as well Of course, for the actual project, I would repeat the data and model preparation as needed It is virtually impossible to tell in advance how much time the deployment would take, before we decide together with customer what exactly the deployment process should cover. Without considering the deployment part, and with the POC project conducted as suggested above (including the transfer of knowledge), the actual project should still only take additional 5 to 10 days. The approximate timeline for the POC project is, as follows: 1-2 days of training 2-3 days for data preparation and data overview 2 days for creating and evaluating the models 1 day for initial preparation of the continuous learning infrastructure 1 day for presentation of the results and discussion of further actions Quite frequently I receive the following question: are we going to find the best possible model during the POC project, or during the actual project? My answer is always quite simple: I do not know. Maybe, if we would spend just one hour more for data preparation, or create just one more model, we could get better patterns and predictions. However, we simply must stop somewhere, and the best possible way to do this, according to my experience, is to restrict the time spent on the project in advance, after an agreement with the customer. You must also never forget that, because we build the complete learning infrastructure and transfer the knowledge, the customer will be capable of doing further investigations independently and improve the models and predictions over time without the need for a constant engagement with me.

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• Array Multiplication and Division

  - by Narfanator

  I came across a question that (eventually) landed me wondering about array arithmetic. I'm thinking specifically in Ruby, but I think the concepts are language independent. So, addition and subtraction are defined, in Ruby, as such: [1,6,8,3,6] + [5,6,7] == [1,6,8,3,6,5,6,7] # All the elements of the first, then all the elements of the second [1,6,8,3,6] - [5,6,7] == [1,8,3] # From the first, remove anything found in the second and array * scalar is defined: [1,2,3] * 2 == [1,2,3,1,2,3] But What, conceptually, should the following be? None of these are (as far as I can find) defined: Array x Array: [1,2,3] * [1,2,3] #=> ? Array / Scalar: [1,2,3,4,5] / 2 #=> ? Array / Scalar: [1,2,3,4,5] % 2 #=> ? Array / Array: [1,2,3,4,5] / [1,2] #=> ? Array / Array: [1,2,3,4,5] % [1,2] #=> ? I've found some mathematical descriptions of these operations for set theory, but I couldn't really follow them, and sets don't have duplicates (arrays do). Edit: Note, I do not mean vector (matrix) arithmetic, which is completely defined. Edit2: If this is the wrong stack exchange, tell me which is the right one and I'll move it. Edit 3: Add mod operators to the list. Edit 4: I figure array / scalar is derivable from array * scalar: a * b = c => a = b / c [1,2,3] * 3 = [1,2,3]+[1,2,3]+[1,2,3] = [1,2,3,1,2,3,1,2,3] => [1,2,3] = [1,2,3,1,2,3,1,2,3] / 3 Which, given that programmer's division ignore the remained and has modulus: [1,2,3,4,5] / 2 = [[1,2], [3,4]] [1,2,3,4,5] % 2 = [5] Except that these are pretty clearly non-reversible operations (not that modulus ever is), which is non-ideal. Edit: I asked a question over on Math that led me to Multisets. I think maybe extensible arrays are "multisets", but I'm not sure yet.

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• SQL SERVER – Validating Spatial Object with IsValidDetailed Function

  - by pinaldave

  What do you prefer – error or warning indicating error may happen with the reason for the error. While writing the previous statement I remember the movie “Minory Report”. This blog post is not about minority report but I will still cover the concept in a single statement “Let us predict the future and prevent the crime which is about to happen in future”. (Please feel free to correct me if I am wrong about the movie concept, I really do not want to hurt your sentiment if you are dedicated fan). Let us switch to the SQL Server world. Spatial data types are interesting concepts. I love writing about spatial data types because it allows me to be creative with shapes (just like toddlers). When working with Spatial Datatypes it is all good when the spatial object works fine. However, when the spatial object has issue or it is created with invalid coordinates it used to give a simple error that there is an issue with the object but did not provide much information. This made it very difficult to debug. If this spatial object was used in the big procedure and while this big procedural error out because of the invalid spatial object, it is indeed very difficult to debug it. I always wished that the more information provided regarding what is the problem with spatial datatype. SQL Server 2012 has introduced the new function IsValidDetailed(). This function has made my life very easy. In simple words this function will check if the spatial object passed is valid or not. If it is valid it will give information that it is valid. If the spatial object is not valid it will return the answer that it is not valid and the reason for the same. This makes it very easy to debug the issue and make the necessary correction. DECLARE @p GEOMETRY = 'Polygon((2 2, 6 6, 4 2, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'Polygon((2 2, 3 3, 4 4, 5 5, 6 6, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'Polygon((2 2, 4 4, 4 2, 2 3, 2 2))' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'CIRCULARSTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'CIRCULARSTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO DECLARE @p GEOMETRY = 'LINESTRING(2 2, 4 4, 0 0)' SELECT @p.IsValidDetailed() GO Here is the resultset of the above query. You can see any valid query and some invalid query. If the query is invalid it also demonstrates the reason along with the error message. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Spatial Database, SQL Spatial

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• PostSharp, Obfuscation, and IL

  - by Simon Cooper

  Aspect-oriented programming (AOP) is a relatively new programming paradigm. Originating at Xerox PARC in 1994, the paradigm was first made available for general-purpose development as an extension to Java in 2001. From there, it has quickly been adapted for use in all the common languages used today. In the .NET world, one of the primary AOP toolkits is PostSharp. Attributes and AOP Normally, attributes in .NET are entirely a metadata construct. Apart from a few special attributes in the .NET framework, they have no effect whatsoever on how a class or method executes within the CLR. Only by using reflection at runtime can you access any attributes declared on a type or type member. PostSharp changes this. By declaring a custom attribute that derives from PostSharp.Aspects.Aspect, applying it to types and type members, and running the resulting assembly through the PostSharp postprocessor, you can essentially declare 'clever' attributes that change the behaviour of whatever the aspect has been applied to at runtime. A simple example of this is logging. By declaring a TraceAttribute that derives from OnMethodBoundaryAspect, you can automatically log when a method has been executed: public class TraceAttribute : PostSharp.Aspects.OnMethodBoundaryAspect { public override void OnEntry(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Entering {0}.{1}.", method.DeclaringType.FullName, method.Name)); } public override void OnExit(MethodExecutionArgs args) { MethodBase method = args.Method; System.Diagnostics.Trace.WriteLine( String.Format( "Leaving {0}.{1}.", method.DeclaringType.FullName, method.Name)); } } [Trace] public void MethodToLog() { ... } Now, whenever MethodToLog is executed, the aspect will automatically log entry and exit, without having to add the logging code to MethodToLog itself. PostSharp Performance Now this does introduce a performance overhead - as you can see, the aspect allows access to the MethodBase of the method the aspect has been applied to. If you were limited to C#, you would be forced to retrieve each MethodBase instance using Type.GetMethod(), matching on the method name and signature. This is slow. Fortunately, PostSharp is not limited to C#. It can use any instruction available in IL. And in IL, you can do some very neat things. Ldtoken C# allows you to get the Type object corresponding to a specific type name using the typeof operator: Type t = typeof(Random); The C# compiler compiles this operator to the following IL: ldtoken [mscorlib]System.Random call class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle( valuetype [mscorlib]System.RuntimeTypeHandle) The ldtoken instruction obtains a special handle to a type called a RuntimeTypeHandle, and from that, the Type object can be obtained using GetTypeFromHandle. These are both relatively fast operations - no string lookup is required, only direct assembly and CLR constructs are used. However, a little-known feature is that ldtoken is not just limited to types; it can also get information on methods and fields, encapsulated in a RuntimeMethodHandle or RuntimeFieldHandle: // get a MethodBase for String.EndsWith(string) ldtoken method instance bool [mscorlib]System.String::EndsWith(string) call class [mscorlib]System.Reflection.MethodBase [mscorlib]System.Reflection.MethodBase::GetMethodFromHandle( valuetype [mscorlib]System.RuntimeMethodHandle) // get a FieldInfo for the String.Empty field ldtoken field string [mscorlib]System.String::Empty call class [mscorlib]System.Reflection.FieldInfo [mscorlib]System.Reflection.FieldInfo::GetFieldFromHandle( valuetype [mscorlib]System.RuntimeFieldHandle) These usages of ldtoken aren't usable from C# or VB, and aren't likely to be added anytime soon (Eric Lippert's done a blog post on the possibility of adding infoof, methodof or fieldof operators to C#). However, PostSharp deals directly with IL, and so can use ldtoken to get MethodBase objects quickly and cheaply, without having to resort to string lookups. The kicker However, there are problems. Because ldtoken for methods or fields isn't accessible from C# or VB, it hasn't been as well-tested as ldtoken for types. This has resulted in various obscure bugs in most versions of the CLR when dealing with ldtoken and methods, and specifically, generic methods and methods of generic types. This means that PostSharp was behaving incorrectly, or just plain crashing, when aspects were applied to methods that were generic in some way. So, PostSharp has to work around this. Without using the metadata tokens directly, the only way to get the MethodBase of generic methods is to use reflection: Type.GetMethod(), passing in the method name as a string along with information on the signature. Now, this works fine. It's slower than using ldtoken directly, but it works, and this only has to be done for generic methods. Unfortunately, this poses problems when the assembly is obfuscated. PostSharp and Obfuscation When using ldtoken, obfuscators don't affect how PostSharp operates. Because the ldtoken instruction directly references the type, method or field within the assembly, it is unaffected if the name of the object is changed by an obfuscator. However, the indirect loading used for generic methods was breaking, because that uses the name of the method when the assembly is put through the PostSharp postprocessor to lookup the MethodBase at runtime. If the name then changes, PostSharp can't find it anymore, and the assembly breaks. So, PostSharp needs to know about any changes an obfuscator does to an assembly. The way PostSharp does this is by adding another layer of indirection. When PostSharp obfuscation support is enabled, it includes an extra 'name table' resource in the assembly, consisting of a series of method & type names. When PostSharp needs to lookup a method using reflection, instead of encoding the method name directly, it looks up the method name at a fixed offset inside that name table: MethodBase genericMethod = typeof(ContainingClass).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: get_Prop1 21: set_Prop1 22: DoFoo 23: GetWibble When the assembly is later processed by an obfuscator, the obfuscator can replace all the method and type names within the name table with their new name. That way, the reflection lookups performed by PostSharp will now use the new names, and everything will work as expected: MethodBase genericMethod = typeof(#kGy).GetMethod(GetNameAtIndex(22)); PostSharp.NameTable resource: ... 20: #kkA 21: #zAb 22: #EF5a 23: #2tg As you can see, this requires direct support by an obfuscator in order to perform these rewrites. Dotfuscator supports it, and now, starting with SmartAssembly 6.6.4, SmartAssembly does too. So, a relatively simple solution to a tricky problem, with some CLR bugs thrown in for good measure. You don't see those every day!

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• Exciting product releases (and one disappointing thing) with Mix10

  - by Jeff

  Sadly, I'm not at Mix this year, for the first time in a few years. It's a little harder to go if you work for Microsoft, oddly enough. And then there's this little guy next to me, who at ten days old really needs his daddy to be around! But oh, the excitement of what Microsoft has in store! It's great to finally see all of these major releases coming together for Microsoft developer products. There is a great deal of excitement among people internally no matter where you work, because there is so much cool stuff in the pipe. In case you live under a rock...Visual Studio 2010 - Great to see all of the positive feedback on the Twitter and what not. I've been using it on one of my home products for awhile, and I really like it. The newer nightly builds of ReSharper also seem to be gaining speed in quality as well. I like the new debugging features, and the text readability is not imagined. Love it.Silverlight 4 - I've been running a couple of minor SL3 apps on my personal sites for awhile now, and I'm thrilled with the platform. With a couple of key concepts down, .NET folk like you and me can do some stellar things with this, and if you're a Mac nerd (like me), it's all kinds of awesome to be able to build stuff for it without the agony of Objective-C and X Code.Windows Phone 7 Series - A few weeks ago you got to see the shiny new UI that went beyond the icon grid, and now you've got the developer story as well. That I can adapt my existing Silverlight apps with minimal effort to work on the phone is pretty powerful. Millions of .NET devs just because phone developers, using the tools they already know. How great is that?ASP.NET MVC2 - The final bits shipped last week, and there was much rejoicing. I love this framework because of the testability and the real ability to get to the true mechanics of HTTP. The other cool thing is the speed at which the framework has evolved. v2 in less than a year is pretty "un-Microsoft" in a lot of eyes.The video of keynotes and sessions is starting to appear on the Mix site, but for reasons I can't understand, they're WMV downloads. For real? Not that helpful for Mac folk. Why wouldn't they be using a Silverlight player?In any case, the thing that continues to motivate me is that getting what you imagine on to the Internet gets easier every year. This is not a new revelation for me. I've only been at Microsoft for four months, but I've felt this way for years. I'm thrilled to be a part of it.

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• Rant on EDI

  - by Anthony Trudeau

  Originally posted on: http://geekswithblogs.net/tonyt/archive/2013/06/27/153261.aspxMy post this month is a rant and not something informational. I hope y'all will forgive me.It's been a slow month. I was on vacation with my daughter for the middle part of the month. And the rest of my time has been preparing for a major ERP upgrade, and dealing with a last minute surprise from a customer that has EDI changes.The subject of EDI is my rant. I was tossed into EDI years ago by the same customer. I understood the basic concepts, but not details -- implementation or otherwise. I started with my network including a couple of people with EDI experience. And for one that was all she did. She was my first taste of what seems to be a protected group.I started looking for the standards with a budget in mind, or rather a lack of budget. See whenever someone stone walls you like that it tells me that what they're doing isn't as mystical as they'd like you to believe. Real magic doesn't need to be kept secret. And that is the case with EDI; however, the EDI industry tries to protect it. You cannot even download the standards. They cost thousands of dollars.All this does is ensure that they continue to rack up consulting dollars from their ignorant clients. Well sirs and madams, I put my finger in your eye. I developed my own translator. And while it's not robust enough to resell due to the limited scope of information I could gather. It did save my employer tens if not over a hundred thousand dollars.My public service message, therefore is as follows. Don't be afraid to tackle implementing EDI if you're even a semi-competent developer. You need some experience parsing, familiarity with your business system, and a little patience. Also, pick your VAN well. Don't fall into the trap of thinking that the biggest names are the best choice. That was a costly mistake for us that we are stuck with for a couple more years.

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• Mexico leading in Business Transformation Strategies:

  - by [email protected]

  By John Burke Group Vice President Oracle Applications Business Unit     I recently completed a business tour in Mexico, and was surprised by both the economic vibrancy of the country and the thought leadership expressed by many of the customers I met.  An example of the economic vibrancy of the country: across the street from my hotel was the local Bentley dealership, Coach Store, Yves Saint Laurent and of course a Starbucks.  I only made it to Starbucks.  Both the Coach Store and YSL had a line of folks waiting to get in... As for thought leadership, there were several illustrations only on the first day. I had the opportunity to meet with a branch of the Mexican Federal Government. Their questions were not about clerical task automation, far from it! We discussed citizen on-line access to fees and services - for example looking up the duty on an international goods shipment, or tracking that my taxes have been received, or the status of my request for a certain service.  Eligibility, policies and status.  Having an integrated rules or policy automation system that would allow businesses and citizens to access accurate information and ensure the proper collection of fees and payment for 3rd party provided services.    Then in the afternoon, I met with the owner of a roofing company (note: most roofs in Mexico are flat and made of cement).  This CEO started discussing how he wanted to transform his business from a cement products company to a service company and market 5-10-15 year service contracts which would guarantee the structural integrity of the roof and of course that the roof would remain waterproof.  Although his products were guaranteed, they required an annual inspection and most home owners never schedule that inspection until it is too late and water damage has occurred.  These emergency calls reduce his margin and reduce customer satisfaction.  This lead to a discussion of business models in general and why long term differentiation can only come from service, not just for the music or news industries, but also for roofing companies!    I completely agreed with the transformational concepts described in both meetings and quickly understood why there is a Bentley dealership near my hotel.    

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• Debugging .NET code called from X++ code in AX 2012

  - by ssmantha

  A very intriguing issue came to me to debug .Net code called from X++ code in AX 2012. This was indeed a challenge to be nailed down. Luckily the tools and some concepts helped me to achieve this task. Here it goes... We need to do a seamless debugging from AX debugger to Visual Studio back and forth. To enable this we need to first see if the dll to be debug is present in GAC then we might need to uninstall it from it due to the order of preference .NET loads the assemblies. The assemblies are first loaded from GAC and then the runtime checks for Public and Private Assemblies. Since the assembly in GAC is always compiled with runtime optimizations it is difficult to debug. We need to unhook this assembly from GAC and then move further relying on >NET assembly loading patterns. Step 1: Remove the target assembly to debug from GAC. Before that stop all the AOS servers and close all the instances of programs which rely on AOT e.g. all clients and even visual studio now. Step 2: Build your sample code which is present in AOT in debug mode and get the dll file along with PDB files. Step 3: Place these files in the Server\..\Bin and Client\bin directories of AX installation. Step 4: Configure Visual Studio: Step 4.1: Configure Debugging Options. In Visual Studio Go to Debug -> Options and Settings -> Debug node -> General sub node and disable “Enable Just My Code (managed)” Step 4.2: Specify the symbol loading directory options. Specify the locations for Client bin and server bin directories of the installation, remember to specify the correct instance of Server bin directory corresponding to your AOS. Step 4.3: Configure the project for debugging Step 5: Ready to go place your breakpoints in X++ and in .Net wherever necessary before this process... Run the Visual studio project and it will invoke the AX client with your breakpoint hitting X++ code.. and when you do a step-in using F11 the Visual studio debugger will be active and from here onwards you would be able to debug the complete flow. Debugging in seamless manner across debuggers is really very good feature and mostly underutilized, but by doing so we can have improved troubleshooting and saves a hell lot of time.. Stay tuned for more in Advanced Debugging..

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• Tap into MySQL's Amazing Performance Results with the Performance Tuning Course

  - by Antoinette O'Sullivan

  Want to leverage the high-speed load utilities, distinctive memory caches, full text indexes, and other performance-enhancing mechanisms that MySQL offers to fuel today's critical business systems. The authentic MySQL Performance Tuning course, in 4 days, teaches you to evaluate the MySQL architecture, learn to use the tools, configure the database for performance, tune application and SQL code, tune the server, examine the storage engines, assess the application architecture, and learn general tuning concepts. You can take this course in one the following three ways: Training-on-Demand: Access the streaming video, instructor delivery of this course from your own desk, at your own pace. Book time for hands-on practice when it suits you. Live-Virtual Class: Take this instructor-led class live from your own desk. With 700 events on the schedule you are sure to find a time and date to suit you! In-Class: Travel to a classroom to take this class. A sample of events on the schedule are as follows.  Location  Date  Delivery Language  Hamburg, Germany  22 October 2012  German  Prague, Czech Republic  1 October 2012  Czech  Warsaw, Poland  3 December 2012  Polish  London, England  19 November 2012  English  Rome, Italy  23 October 2012  Italian Lisbon, Portugal  6 November 2012  European Portugese  Aix en Provence, France  4 September 2012   French  Strasbourg, France 16 October 2012   French  Nieuwegein, Netherlands 26 November 2012   Dutch  Madrid, Spain 17 December 2012   Spanish  Mechelen, Belgium  1 October 2012  English  Riga, Latvia  10 December 2012  Latvian  Petaling Jaya, Malaysia  10 September 2012 English   Edmonton, Canada 10 December 2012   English  Vancouver, Canada 10 December 2012   English  Ottawa, Canada 26 November 2012   English  Toronto, Canada 26 November 2012   English  Montreal, Canada 26 November 2012   English  Mexico City, Mexico 10 September 2012   Spanish  Sao Paolo, Brazil 26 November 2012  Brazilian Portugese   Tokyo, Japan 19 November 2012   Japanese  Tokyo, Japan  19 November 2012  Japanese For further information on this class, or to register your interest in additional events, go to the Oracle University Portal: http://oracle.com/education/mysql

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• Unit Testing TSQL

  - by Grant Fritchey

  I went through a period of time where I spent a lot of effort figuring out how to set up unit tests for TSQL. It wasn't easy. There are a few tools out there that help, but mostly it involves lots of programming. well, not as much as before. Thanks to the latest Down Tools Week at Red Gate a new utility has been built and released into the wild, SQL Test. Like a lot of the new tools coming out of Red Gate these days, this one is directly integrated into SSMS, which means you're working where you're comfortable and where you already have lots of tools at your disposal. After the install, when you launch SSMS and get connected, you're prompted to install the tSQLt example database. Go for it. It's a quick way to see how the tool works. I'd suggest using it. It' gives you a quick leg up. The concepts are pretty straight forward. There are a series of CLR commands that you use to configure a test and the test assertions. In between you're calling TSQL, either calls to your structure, queries, or stored procedures. They already have the one things that I always found wanting in database tests, a way to compare tables of results. I also like the ability to create a dummy copy of tables for the tests. It lets you control structures and behaviors so that the tests are more focused. One of the issues I always ran into with the other testing tools is that setting up the tests might require potentially destructive changes to the structure of the database (dropping FKs, etc.) which added lots of time and effort to setting up the tests, making testing more difficult, and therefor, less useful. Functionally, this is pretty similar to the Visual Studio tests and TSQLUnit tests that I used to use. The primary improvement over the Visual Studio tests is that I'm working in SSMS instead of Visual Studio. The primary improvement over TSQLUnit is the SQL Test interface it self. A lot of the functionality is the same, but having a sweet little tool to manage & run the tests from makes a huge difference. Oh, and don't worry. You can still run these tests directly from TSQL too, so automation has not gone away. I'm still thinking about how I'd use this in a dev environment where I also had source control to fret. That might be another blog post right there. I'm just getting started with SQL Test, so this is the first of several blog posts & videos. Watch this space. Try the tool.

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• ArchBeat Link-o-Rama for 2012-04-11

  - by Bob Rhubart

  Oracle Technology Network Developer Day: MySQL - New York www.oracle.com Wednesday, May 02, 2012 8:00 AM – 4:30 PM Grand Hyatt New York 109 East 42nd Street, Grand Central Terminal New York, NY 10017 OTN Architect Day - Reston, VA - May 16 www.oracle.com The live one-day event in Reston, VA brings together architects from a broad range of disciplines and domains to share insights and expertise in the use of Oracle technologies to meet the challenges today’s solution architects regularly face. Registration is free, but seating is limited. InfoQ: Seven Secrets Every Architect Should Know www.infoq.com Frank Buschmann’s secrets: User Tasks-based Design, Be Minimalist, Ensure Visibility of Domain Concepts, Use Uncertainty as a Driver, Design Between Things, Check Assumptions, Eat Your Own Dog Food. Roadmaps for the IT shop’s evolution | Andy Mulholland www.capgemini.com Andy Mulholland discusses "the challenge of new technology and the disruptive change it brings, together with the needs to understand and plan, or even try to gain control of end-users implementations." Drive Online Engagement with Intuitive Portals and Websites | Kellsey Ruppel blogs.oracle.com "The web presence must be able to scale to support the delivery of personalized and targeted content to thousands of site visitors without sacrificing performance," says WebCenter blogger Kellsey Ruppel. "And integration between systems becomes more important as well, as organizations strive to obtain one view of the customer culled from WCM data, CRM data and more." New Exadata Customer Cases | Javier Puerta blogs.oracle.com Javier Puerta shares links to four new customer use cases featuring details on the solutions implemented at each of these sizable companies. Invoicing: It's time to catch up! | Jesper Mol www.nl.capgemini.com Capgemini's Jesper Mol diagrams an e-invoicing solution that includes Oracle Service Bus. Using SAP Adapter with OSB 11g (PS3) | Shub Lahiri blogs.oracle.com Shub Lahiri shares a brief overview outlining the steps required to build such a simple project with Oracle Service Bus 11g and SAP Adapter for the PS3 release. Northeast Ohio Oracle Users Group 2 Day Seminar - May 14-15 - Cleveland, OH www.neooug.org More than 20 sessions over 4 tracks, featuring 18 speakers, including Oracle ACE Director Cary Millsap, Oracle ACE Director Rich Niemiec, and Oracle ACE Stewart Brand. Register before April 15 and save. Thought for the Day "Today, most software exists, not to solve a problem, but to interface with other software." — I. O. Angell

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• NUMA-aware placement of communication variables

  - by Dave

  For classic NUMA-aware programming I'm typically most concerned about simple cold, capacity and compulsory misses and whether we can satisfy the miss by locally connected memory or whether we have to pull the line from its home node over the coherent interconnect -- we'd like to minimize channel contention and conserve interconnect bandwidth. That is, for this style of programming we're quite aware of where memory is homed relative to the threads that will be accessing it. Ideally, a page is collocated on the node with the thread that's expected to most frequently access the page, as simple misses on the page can be satisfied without resorting to transferring the line over the interconnect. The default "first touch" NUMA page placement policy tends to work reasonable well in this regard. When a virtual page is first accessed, the operating system will attempt to provision and map that virtual page to a physical page allocated from the node where the accessing thread is running. It's worth noting that the node-level memory interleaving granularity is usually a multiple of the page size, so we can say that a given page P resides on some node N. That is, the memory underlying a page resides on just one node. But when thinking about accesses to heavily-written communication variables we normally consider what caches the lines underlying such variables might be resident in, and in what states. We want to minimize coherence misses and cache probe activity and interconnect traffic in general. I don't usually give much thought to the location of the home NUMA node underlying such highly shared variables. On a SPARC T5440, for instance, which consists of 4 T2+ processors connected by a central coherence hub, the home node and placement of heavily accessed communication variables has very little impact on performance. The variables are frequently accessed so likely in M-state in some cache, and the location of the home node is of little consequence because a requester can use cache-to-cache transfers to get the line. Or at least that's what I thought. Recently, though, I was exploring a simple shared memory point-to-point communication model where a client writes a request into a request mailbox and then busy-waits on a response variable. It's a simple example of delegation based on message passing. The server polls the request mailbox, and having fetched a new request value, performs some operation and then writes a reply value into the response variable. As noted above, on a T5440 performance is insensitive to the placement of the communication variables -- the request and response mailbox words. But on a Sun/Oracle X4800 I noticed that was not the case and that NUMA placement of the communication variables was actually quite important. For background an X4800 system consists of 8 Intel X7560 Xeons . Each package (socket) has 8 cores with 2 contexts per core, so the system is 8x8x2. Each package is also a NUMA node and has locally attached memory. Every package has 3 point-to-point QPI links for cache coherence, and the system is configured with a twisted ladder "mobius" topology. The cache coherence fabric is glueless -- there's not central arbiter or coherence hub. The maximum distance between any two nodes is just 2 hops over the QPI links. For any given node, 3 other nodes are 1 hop distant and the remaining 4 nodes are 2 hops distant. Using a single request (client) thread and a single response (server) thread, a benchmark harness explored all permutations of NUMA placement for the two threads and the two communication variables, measuring the average round-trip-time and throughput rate between the client and server. In this benchmark the server simply acts as a simple transponder, writing the request value plus 1 back into the reply field, so there's no particular computation phase and we're only measuring communication overheads. In addition to varying the placement of communication variables over pairs of nodes, we also explored variations where both variables were placed on one page (and thus on one node) -- either on the same cache line or different cache lines -- while varying the node where the variables reside along with the placement of the threads. The key observation was that if the client and server threads were on different nodes, then the best placement of variables was to have the request variable (written by the client and read by the server) reside on the same node as the client thread, and to place the response variable (written by the server and read by the client) on the same node as the server. That is, if you have a variable that's to be written by one thread and read by another, it should be homed with the writer thread. For our simple client-server model that means using split request and response communication variables with unidirectional message flow on a given page. This can yield up to twice the throughput of less favorable placement strategies. Our X4800 uses the QPI 1.0 protocol with source-based snooping. Briefly, when node A needs to probe a cache line it fires off snoop requests to all the nodes in the system. Those recipients then forward their response not to the original requester, but to the home node H of the cache line. H waits for and collects the responses, adjudicates and resolves conflicts and ensures memory-model ordering, and then sends a definitive reply back to the original requester A. If some node B needed to transfer the line to A, it will do so by cache-to-cache transfer and let H know about the disposition of the cache line. A needs to wait for the authoritative response from H. So if a thread on node A wants to write a value to be read by a thread on node B, the latency is dependent on the distances between A, B, and H. We observe the best performance when the written-to variable is co-homed with the writer A. That is, we want H and A to be the same node, as the writer doesn't need the home to respond over the QPI link, as the writer and the home reside on the very same node. With architecturally informed placement of communication variables we eliminate at least one QPI hop from the critical path. Newer Intel processors use the QPI 1.1 coherence protocol with home-based snooping. As noted above, under source-snooping a requester broadcasts snoop requests to all nodes. Those nodes send their response to the home node of the location, which provides memory ordering, reconciles conflicts, etc., and then posts a definitive reply to the requester. In home-based snooping the snoop probe goes directly to the home node and are not broadcast. The home node can consult snoop filters -- if present -- and send out requests to retrieve the line if necessary. The 3rd party owner of the line, if any, can respond either to the home or the original requester (or even to both) according to the protocol policies. There are myriad variations that have been implemented, and unfortunately vendor terminology doesn't always agree between vendors or with the academic taxonomy papers. The key is that home-snooping enables the use of a snoop filter to reduce interconnect traffic. And while home-snooping might have a longer critical path (latency) than source-based snooping, it also may require fewer messages and less overall bandwidth. It'll be interesting to reprise these experiments on a platform with home-based snooping. While collecting data I also noticed that there are placement concerns even in the seemingly trivial case when both threads and both variables reside on a single node. Internally, the cores on each X7560 package are connected by an internal ring. (Actually there are multiple contra-rotating rings). And the last-level on-chip cache (LLC) is partitioned in banks or slices, which with each slice being associated with a core on the ring topology. A hardware hash function associates each physical address with a specific home bank. Thus we face distance and topology concerns even for intra-package communications, although the latencies are not nearly the magnitude we see inter-package. I've not seen such communication distance artifacts on the T2+, where the cache banks are connected to the cores via a high-speed crossbar instead of a ring -- communication latencies seem more regular.

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