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• Task-It Webinar - Source Code

  Last week I presented a webinar called "Building a real-world application with RadControls for Silverlight 4". For those that didn't get to see the webinar, you can view it here: Building a read-world application with RadControls for Silverlight 4 Since the webinar I've received several requests asking if I could post the source code for the simple application I showed demonstrating some of the techniques used in the development of Task-It, such as MVVM, Commands and Internationalization. This source code is now available for downloadhere. After downloading the source: Extract it to the location of your choice on your hard-drive Open the solution Right-click ModuleProject.Web and selecte 'Set as StartUp Project'. Right-click ProjectTestPage.aspx and selected 'Set as Start Page' Create a database in SQL Server called WebinarProject. Navigate to the Database folder under the WebinarProject directory and run the .sql script against your WebinarProject database. The last two steps are necessary only for the Tasks page to work properly (using WCF RIA Services). Now some notes about each page: Code-behind This is not the way I recommend coding a line-of-business application in Silverlight, but simply wanted to show how the code-behind approach would look. Command This page introduces MVVM and Commands. You'll notice in the XAML that the Command property of theRadMenuItem and the Button are both bound to a SaveCommand. That comes from the view model. If you look in the code- behind of the user control you'll see that an instance of a CommandViewModel is instantiated and set as the DataContext of the UserControl.There is also a listener for the view model's SaveCompleted event. When this is fired, it tells the view (UserControl) to display the MessageBox. Internationalization This sample is similar to the previous one, but instead of using hard-coded strings in the UI, the strings are obtained via binding toview model properties. The view model gets the strings from the .resx files (Strings.resx or Strings.de.resx) under Assets/Resources. If you uncomment the call to ShowGerman() in App.xaml.cs's Application_Startup method and re-run the application, you will see the UI in German. Note that this code, which sets the CurrentCulture and CurrentUICulture on the current thread to "de" (German) is for testing purposes only. RadWindow Once again, very similar to the previous example.The difference is that we are now using a RadWindow to display the 'Saved' message instead of a MessageBox. The advantage here is that we do not have to hold on to a reference to the view model in our code behind so that we can get the 'Saved' message from it. The RadWindow's DataContext is now also bound to the view model, so within its XAML we can bind directly to properties in the view model. Much nicer, and cleaner. One other thing I introduced in this example is the use of spacer Rectangles. Rather than setting a width and/or height on the rectangles for spacing, I am now referencing a style in my ResourceDictionary called StandardSpacerStyle. I like doing this better than using margins or padding because now I have a reusable way to create space between elements, the Rectangle does not show (because I have not set its Fill color), and I can change my spacing throughout the user interface in one place if I'd like. Tasks This page is quite a bit different than the other four. It is a very simple, stripped-down version of the Tasks page in the Task-It application. The Tasks.xaml UserControl has a ContentControl, and the Content of that control is set based on whether we are looking at the list of tasks or editing a task. So it displays one of two child UserControls, which are called List and Details. List has the RadGridView, Details has the form. In the code-behind of the Tasks UserControl I am once again setting its DataContext to a view model class. The nice thing is, whichever child UserControl is being displayed (List or Details) inherits its DataContext from its parent control (Tasks), so I do not have to explicitly set it. The List UserControl simply displays a RadGridView whose ItemsSource is bound to a property in the view model called Tasks, and its SelectedItem property is bound to a property in the view model called SelectedItem. The SelectedItem binding must be TwoWay so that the view is notified when the SelectedItem changes in the view model, and the view model is notified when something changes in the view (like when a user changes the Name and/or DueDate in the form). You'll also notice that the form's TextBox and RadDatePicker are also TwoWay bound to the SelectedItem property in the view model. You can experiment with the binding by removing TwoWay and see how changes in the form do not show up in the RadGridView. So here we have an example of two different views (List and Details) that are both bound to the same view model...and actually, so is the Tasks UserControl, so it is really three views. WCF RIA Services By the way, I am using WCF RIA Services to retrieve data for the RadGridView and save the data when the user clicks the Save button in the form. I created a really simple ADO.NET Entity Data Model in WebinarProject.Web called DataModel.edmx. I also created a simple Domain Data Service called DataService that has methods for retrieving data, inserting, updating and deleting. However I am only using the retrieval and update methods in this sample. Note that I do not currently have any validation in place on the form, as I wanted to keep the sample as simple as possible. Wrap up Technically, I should move the calls to WCF RIA Services out of the view model and put them into a separate layer, but this works for now, and that is a topic for another day! Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Sound vs. Valid Argument

  - by MarkPearl

  Today I spent some time reviewing my Formal Logic course for my up coming exam. I came across a section that I have never really explored in any proper depth… the difference between a valid argument and a sound argument. Here go some notes I made… What is an argument? In this case we are not referring to a verbal fight, but more what we call a set of premise followed by a conclusion. Before we go further we need to understand what a premise is… a premise is a statement that an argument claims will induce or justify a conclusion. Think of a premise as an assumption that something is true. So, an argument can consist of one or more premises and a conclusion… When is an argument valid? An argument can be either valid or invalid. An argument is valid if, and only if, it is impossible for there to be a situation in which all it's premises are TRUE and it's conclusion is FALSE. It is generally easier to determine if an argument is invalid. Do this by applying the following… Assume that all the premises are true, then ask yourself if it is now possible for the conclusion to be false. If the answer is "yes," the argument is invalid. If it's "no," the argument is valid. Example 1… P1 – Mark is Tall P2 – Mark is a boy C –  Mark is a tall boy Walkthrough 1… Assume Mark is Tall is true and also assume that Mark is a boy. Based on these two premises, the conclusion is also true – Mark is a tall boy, thus the it is a valid argument. Let’s make this an invalid argument…   Example 2… P1 – Mark is Tall P2 – Mark is a boy C – Mark is a short boy Walkthrough 2… This would be an invalid argument, since from the premises we assume that Mark is tall and he is a boy, and then the conclusion goes against this by saying that Mark is short. Thus an invalid argument.   When is an argument sound? An argument is said to be sound when it is valid and all the premises are indeed true (not just assumed to be true). Rephrased, an argument is said to be sound when the conclusion will follow from the premises and the premises are indeed true in real life. In example 1 we were referring to a specific person, if we generalized it a bit we could come up with the following example.   Example 3 P1 – All people called Mark are tall P2 – I know a specific person called Mark C – He is a tall person   In this instance, it is a valid argument (we assume the premises are true, which leads to the conclusion being true), but the argument is NOT sound. In the real world there must be at least one person called Mark who is not tall. Something also to note, all invalid arguments are also unsound – this makes sense, if an argument is not valid, how on earth can it be true in the real world.   What happens when the premises contradict themselves? This is an interesting one… An argument is valid if, and only if, it is impossible for there to be a situation in which all it's premises are TRUE and it's conclusion is FALSE. When premises are contradictory, the argument is always valid because it is impossible for all the premises to be true at one time. Lets look at an example.. P1 - Elvis is dead P2 – Elvis is alive C – Laura is a woolly mammoth This is a valid argument, but not a sound one. Think about it. Is it possible to have a situation in which the premises are true and the conclusion is false? Sure, it's possible to have a situation in which the conclusion is false, but for the argument to be invalid, it has to be possible for the premises to all be true at the same time the conclusion is false. So if the premises can't all be true, the argument is valid. (If you still think the argument is invalid, draw a picture in which the premises are all true and the conclusion is false. Remember, there's only one Elvis, and you can't be both dead and alive.) For more info on this I suggest reading the following blog post.

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• Optimizing collision engine bottleneck

  - by Vittorio Romeo

  Foreword: I'm aware that optimizing this bottleneck is not a necessity - the engine is already very fast. I, however, for fun and educational purposes, would love to find a way to make the engine even faster. I'm creating a general-purpose C++ 2D collision detection/response engine, with an emphasis on flexibility and speed. Here's a very basic diagram of its architecture: Basically, the main class is World, which owns (manages memory) of a ResolverBase*, a SpatialBase* and a vector<Body*>. SpatialBase is a pure virtual class which deals with broad-phase collision detection. ResolverBase is a pure virtual class which deals with collision resolution. The bodies communicate to the World::SpatialBase* with SpatialInfo objects, owned by the bodies themselves. There currenly is one spatial class: Grid : SpatialBase, which is a basic fixed 2D grid. It has it's own info class, GridInfo : SpatialInfo. Here's how its architecture looks: The Grid class owns a 2D array of Cell*. The Cell class contains two collection of (not owned) Body*: a vector<Body*> which contains all the bodies that are in the cell, and a map<int, vector<Body*>> which contains all the bodies that are in the cell, divided in groups. Bodies, in fact, have a groupId int that is used for collision groups. GridInfo objects also contain non-owning pointers to the cells the body is in. As I previously said, the engine is based on groups. Body::getGroups() returns a vector<int> of all the groups the body is part of. Body::getGroupsToCheck() returns a vector<int> of all the groups the body has to check collision against. Bodies can occupy more than a single cell. GridInfo always stores non-owning pointers to the occupied cells. After the bodies move, collision detection happens. We assume that all bodies are axis-aligned bounding boxes. How broad-phase collision detection works: Part 1: spatial info update For each Body body: Top-leftmost occupied cell and bottom-rightmost occupied cells are calculated. If they differ from the previous cells, body.gridInfo.cells is cleared, and filled with all the cells the body occupies (2D for loop from the top-leftmost cell to the bottom-rightmost cell). body is now guaranteed to know what cells it occupies. For a performance boost, it stores a pointer to every map<int, vector<Body*>> of every cell it occupies where the int is a group of body->getGroupsToCheck(). These pointers get stored in gridInfo->queries, which is simply a vector<map<int, vector<Body*>>*>. body is now guaranteed to have a pointer to every vector<Body*> of bodies of groups it needs to check collision against. These pointers are stored in gridInfo->queries. Part 2: actual collision checks For each Body body: body clears and fills a vector<Body*> bodiesToCheck, which contains all the bodies it needs to check against. Duplicates are avoided (bodies can belong to more than one group) by checking if bodiesToCheck already contains the body we're trying to add. const vector<Body*>& GridInfo::getBodiesToCheck() { bodiesToCheck.clear(); for(const auto& q : queries) for(const auto& b : *q) if(!contains(bodiesToCheck, b)) bodiesToCheck.push_back(b); return bodiesToCheck; } The GridInfo::getBodiesToCheck() method IS THE BOTTLENECK. The bodiesToCheck vector must be filled for every body update because bodies could have moved meanwhile. It also needs to prevent duplicate collision checks. The contains function simply checks if the vector already contains a body with std::find. Collision is checked and resolved for every body in bodiesToCheck. That's it. So, I've been trying to optimize this broad-phase collision detection for quite a while now. Every time I try something else than the current architecture/setup, something doesn't go as planned or I make assumption about the simulation that later are proven to be false. My question is: how can I optimize the broad-phase of my collision engine maintaining the grouped bodies approach? Is there some kind of magic C++ optimization that can be applied here? Can the architecture be redesigned in order to allow for more performance? Actual implementation: SSVSCollsion Body.h, Body.cpp World.h, World.cpp Grid.h, Grid.cpp Cell.h, Cell.cpp GridInfo.h, GridInfo.cpp

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• C++ Little Wonders: The C++11 auto keyword redux

  - by James Michael Hare

  I’ve decided to create a sub-series of my Little Wonders posts to focus on C++.  Just like their C# counterparts, these posts will focus on those features of the C++ language that can help improve code by making it easier to write and maintain.  The index of the C# Little Wonders can be found here. This has been a busy week with a rollout of some new website features here at my work, so I don’t have a big post for this week.  But I wanted to write something up, and since lately I’ve been renewing my C++ skills in a separate project, it seemed like a good opportunity to start a C++ Little Wonders series.  Most of my development work still tends to focus on C#, but it was great to get back into the saddle and renew my C++ knowledge.  Today I’m going to focus on a new feature in C++11 (formerly known as C++0x, which is a major move forward in the C++ language standard).  While this small keyword can seem so trivial, I feel it is a big step forward in improving readability in C++ programs. The auto keyword If you’ve worked on C++ for a long time, you probably have some passing familiarity with the old auto keyword as one of those rarely used C++ keywords that was almost never used because it was the default. That is, in the code below (before C++11): 1: int foo() 2: { 3: // automatic variables (allocated and deallocated on stack) 4: int x; 5: auto int y; 6:  7: // static variables (retain their value across calls) 8: static int z; 9:  10: return 0; 11: } The variable x is assumed to be auto because that is the default, thus it is unnecessary to specify it explicitly as in the declaration of y below that.  Basically, an auto variable is one that is allocated and de-allocated on the stack automatically.  Contrast this to static variables, that are allocated statically and exist across the lifetime of the program. Because auto was so rarely (if ever) used since it is the norm, they decided to remove it for this purpose and give it new meaning in C++11.  The new meaning of auto: implicit typing Now, if your compiler supports C++ 11 (or at least a good subset of C++11 or 0x) you can take advantage of type inference in C++.  For those of you from the C# world, this means that the auto keyword in C++ now behaves a lot like the var keyword in C#! For example, many of us have had to declare those massive type declarations for an iterator before.  Let’s say we have a std::map of std::string to int which will map names to ages: 1: std::map<std::string, int> myMap; And then let’s say we want to find the age of a given person: 1: // Egad that's a long type... 2: std::map<std::string, int>::const_iterator pos = myMap.find(targetName); Notice that big ugly type definition to declare variable pos?  Sure, we could shorten this by creating a typedef of our specific map type if we wanted, but now with the auto keyword there’s no need: 1: // much shorter! 2: auto pos = myMap.find(targetName); The auto now tells the compiler to determine what type pos should be based on what it’s being assigned to.  This is not dynamic typing, it still determines the type as if it were explicitly declared and once declared that type cannot be changed.  That is, this is invalid: 1: // x is type int 2: auto x = 42; 3:  4: // can't assign string to int 5: x = "Hello"; Once the compiler determines x is type int it is exactly as if we typed int x = 42; instead, so don’t' confuse it with dynamic typing, it’s still very type-safe. An interesting feature of the auto keyword is that you can modify the inferred type: 1: // declare method that returns int* 2: int* GetPointer(); 3:  4: // p1 is int*, auto inferred type is int 5: auto *p1 = GetPointer(); 6:  7: // ps is int*, auto inferred type is int* 8: auto p2 = GetPointer(); Notice in both of these cases, p1 and p2 are determined to be int* but in each case the inferred type was different.  because we declared p1 as auto *p1 and GetPointer() returns int*, it inferred the type int was needed to complete the declaration.  In the second case, however, we declared p2 as auto p2 which means the inferred type was int*.  Ultimately, this make p1 and p2 the same type, but which type is inferred makes a difference, if you are chaining multiple inferred declarations together.  In these cases, the inferred type of each must match the first: 1: // Type inferred is int 2: // p1 is int* 3: // p2 is int 4: // p3 is int& 5: auto *p1 = GetPointer(), p2 = 42, &p3 = p2; Note that this works because the inferred type was int, if the inferred type was int* instead: 1: // syntax error, p1 was inferred to be int* so p2 and p3 don't make sense 2: auto p1 = GetPointer(), p2 = 42, &p3 = p2; You could also use const or static to modify the inferred type: 1: // inferred type is an int, theAnswer is a const int 2: const auto theAnswer = 42; 3:  4: // inferred type is double, Pi is a static double 5: static auto Pi = 3.1415927; Thus in the examples above it inferred the types int and double respectively, which were then modified to const and static. Summary The auto keyword has gotten new life in C++11 to allow you to infer the type of a variable from it’s initialization.  This simple little keyword can be used to cut down large declarations for complex types into a much more readable form, where appropriate.   Technorati Tags: C++, C++11, Little Wonders, auto

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• SQL SERVER – Simple Example to Configure Resource Governor – Introduction to Resource Governor

  - by pinaldave

  Let us jump right away with question and answer mode. What is resource governor? Resource Governor is a feature which can manage SQL Server Workload and System Resource Consumption. We can limit the amount of CPU and memory consumption by limiting /governing /throttling on the SQL Server. Why is resource governor required? If there are different workloads running on SQL Server and each of the workload needs different resources or when workloads are competing for resources with each other and affecting the performance of the whole server resource governor is a very important task. What will be the real world example of need of resource governor? Here are two simple scenarios where the resource governor can be very useful. Scenario 1: A server which is running OLTP workload and various resource intensive reports on the same server. The ideal situation is where there are two servers which are data synced with each other and one server runs OLTP transactions and the second server runs all the resource intensive reports. However, not everybody has the luxury to set up this kind of environment. In case of the situation where reports and OLTP transactions are running on the same server, limiting the resources to the reporting workload it can be ensured that OTLP’s critical transaction is not throttled. Scenario 2: There are two DBAs in one organization. One DBA A runs critical queries for business and another DBA B is doing maintenance of the database. At any point in time the DBA A’s work should not be affected but at the same time DBA B should be allowed to work as well. The ideal situation is that when DBA B starts working he get some resources but he can’t get more than defined resources. Does SQL Server have any default resource governor component? Yes, SQL Server have two by default created resource governor component. 1) Internal –This is used by database engine exclusives and user have no control. 2) Default – This is used by all the workloads which are not assigned to any other group. What are the major components of the resource governor? Resource Pools Workload Groups Classification In simple words here is what the process of resource governor is. Create resource pool Create a workload group Create classification function based on the criteria specified Enable Resource Governor with classification function Let me further explain you the same with graphical image. Is it possible to configure resource governor with T-SQL? Yes, here is the code for it with explanation in between. Step 0: Here we are assuming that there are separate login accounts for Reporting server and OLTP server. /*----------------------------------------------- Step 0: (Optional and for Demo Purpose) Create Two User Logins 1) ReportUser, 2) PrimaryUser Use ReportUser login for Reports workload Use PrimaryUser login for OLTP workload -----------------------------------------------*/ Step 1: Creating Resource Pool We are creating two resource pools. 1) Report Server and 2) Primary OLTP Server. We are giving only a few resources to the Report Server Pool as described in the scenario 1 the other server is mission critical and not the report server. ----------------------------------------------- -- Step 1: Create Resource Pool ----------------------------------------------- -- Creating Resource Pool for Report Server CREATE RESOURCE POOL ReportServerPool WITH ( MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30, MIN_MEMORY_PERCENT=0, MAX_MEMORY_PERCENT=30) GO -- Creating Resource Pool for OLTP Primary Server CREATE RESOURCE POOL PrimaryServerPool WITH ( MIN_CPU_PERCENT=50, MAX_CPU_PERCENT=100, MIN_MEMORY_PERCENT=50, MAX_MEMORY_PERCENT=100) GO Step 2: Creating Workload Group We are creating two workloads each mapping to each of the resource pool which we have just created. ----------------------------------------------- -- Step 2: Create Workload Group ----------------------------------------------- -- Creating Workload Group for Report Server CREATE WORKLOAD GROUP ReportServerGroup USING ReportServerPool ; GO -- Creating Workload Group for OLTP Primary Server CREATE WORKLOAD GROUP PrimaryServerGroup USING PrimaryServerPool ; GO Step 3: Creating user defiled function which routes the workload to the appropriate workload group. In this example we are checking SUSER_NAME() and making the decision of Workgroup selection. We can use other functions such as HOST_NAME(), APP_NAME(), IS_MEMBER() etc. ----------------------------------------------- -- Step 3: Create UDF to Route Workload Group ----------------------------------------------- CREATE FUNCTION dbo.UDFClassifier() RETURNS SYSNAME WITH SCHEMABINDING AS BEGIN DECLARE @WorkloadGroup AS SYSNAME IF(SUSER_NAME() = 'ReportUser') SET @WorkloadGroup = 'ReportServerGroup' ELSE IF (SUSER_NAME() = 'PrimaryServerPool') SET @WorkloadGroup = 'PrimaryServerGroup' ELSE SET @WorkloadGroup = 'default' RETURN @WorkloadGroup END GO Step 4: In this final step we enable the resource governor with the classifier function created in earlier step 3. ----------------------------------------------- -- Step 4: Enable Resource Governer -- with UDFClassifier ----------------------------------------------- ALTER RESOURCE GOVERNOR WITH (CLASSIFIER_FUNCTION=dbo.UDFClassifier); GO ALTER RESOURCE GOVERNOR RECONFIGURE GO Step 5: If you are following this demo and want to clean up your example, you should run following script. Running them will disable your resource governor as well delete all the objects created so far. ----------------------------------------------- -- Step 5: Clean Up -- Run only if you want to clean up everything ----------------------------------------------- ALTER RESOURCE GOVERNOR WITH (CLASSIFIER_FUNCTION = NULL) GO ALTER RESOURCE GOVERNOR DISABLE GO DROP FUNCTION dbo.UDFClassifier GO DROP WORKLOAD GROUP ReportServerGroup GO DROP WORKLOAD GROUP PrimaryServerGroup GO DROP RESOURCE POOL ReportServerPool GO DROP RESOURCE POOL PrimaryServerPool GO ALTER RESOURCE GOVERNOR RECONFIGURE GO I hope this introductory example give enough light on the subject of Resource Governor. In future posts we will take this same example and learn a few more details. 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: Resource Governor

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• Oracle Linux and Oracle VM pricing guide

  - by wcoekaer

  A few days ago someone showed me a pricing guide from a Linux vendor and I was a bit surprised at the complexity of it. Especially when you look at larger servers (4 or 8 sockets) and when adding virtual machine use into the mix. I think we have a very compelling and simple pricing model for both Oracle Linux and Oracle VM. Let me see if I can explain it in 1 page, not 10 pages. This pricing information is publicly available on the Oracle store, I am using the current public list prices. Also keep in mind that this is for customers using non-oracle x86 servers. When a customer purchases an Oracle x86 server, the annual systems support includes full use (all you can eat) of Oracle Linux, Oracle VM and Oracle Solaris (no matter how many VMs you run on that server, in case you deploy guests on a hypervisor). This support level is the equivalent of premier support in the list below. Let's start with Oracle VM (x86) : Oracle VM support subscriptions are per physical server on which you deploy the Oracle VM Server product. (1) Oracle VM Premier Limited - 1- or 2 socket server : $599 per server per year (2) Oracle VM Premier - more than 2 socket server (4, or 8 or whatever more) : $1199 per server per year The above includes the use of Oracle VM Manager and Oracle Enterprise Manager Cloud Control's Virtualization management pack (including self service cloud portal, etc..) 24x7 support, access to bugfixes, updates and new releases. It also includes all options, live migrate, dynamic resource scheduling, high availability, dynamic power management, etc If you want to play with the product, or even use the product without access to support services, the product is freely downloadable from edelivery. Next, Oracle Linux : Oracle Linux support subscriptions are per physical server. If you plan to run Oracle Linux as a guest on Oracle VM, VMWare or Hyper-v, you only have to pay for a single subscription per system, we do not charge per guest or per number of guests. In other words, you can run any number of Oracle Linux guests per physical server and count it as just a single subscription. (1) Oracle Linux Network Support - any number of sockets per server : $119 per server per year Network support does not offer support services. It provides access to the Unbreakable Linux Network and also offers full indemnification for Oracle Linux. (2) Oracle Linux Basic Limited Support - 1- or 2 socket servers : $499 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management. It includes ocfs2 as a clustered filesystem. (3) Oracle Linux Basic Support - more than 2 socket server (4, or 8 or more) : $1199 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management. It includes ocfs2 as a clustered filesystem (4) Oracle Linux Premier Limited Support - 1- or 2 socket servers : $1399 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management, XFS filesystem support. It also offers Oracle Lifetime support, backporting of patches for critical customers in previous versions of package and ksplice zero-downtime updates. (5) Oracle Linux Premier Support - more than 2 socket servers : $2299 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management, XFS filesystem support. It also offers Oracle Lifetime support, backporting of patches for critical customers in previous versions of package and ksplice zero-downtime updates. (6) Freely available Oracle Linux - any number of sockets You can freely download Oracle Linux, install it on any number of servers and use it for any reason, without support, without right to use of these extra features like Oracle Clusterware or ksplice, without indemnification. However, you do have full access to all errata as well. Need support? then use options (1)..(5) So that's it. Count number of 2 socket boxes, more than 2 socket boxes, decide on basic or premier support level and you are done. You don't have to worry about different levels based on how many virtual instance you deploy or want to deploy. A very simple menu of choices. We offer, inclusive, Linux OS clusterware, Linux OS Management, provisioning and monitoring, cluster filesystem (ocfs), high performance filesystem (xfs), dtrace, ksplice, ofed (infiniband stack for high performance networking). No separate add-on menus. NOTE : socket/cpu can have any number of cores. So whether you have a 4,6,8,10 or 12 core CPU doesn't matter, we count the number of physical CPUs.

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• Verizon Wireless Supports its Mission-Critical Employee Portal with MySQL

  - by Bertrand Matthelié

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Cambria","serif"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} Verizon Wireless, the #1 mobile carrier in the United States, operates the nation’s largest 3G and 4G LTE network, with the most subscribers (109 millions) and the highest revenue ($70.2 Billion in 2011). Verizon Wireless built the first wide-area wireless broadband network and delivered the first wireless consumer 3G multimedia service in the US, and offers global voice and data services in more than 200 destinations around the world. To support 4.2 million daily wireless transactions and 493,000 calls and emails transactions produced by 94.2 million retail customers, Verizon Wireless employs over 78,000 employees with area headquarters across the United States. The Business Challenge Seeing the stupendous rise in social media, video streaming, live broadcasting…etc which redefined the scope of technology, Verizon Wireless, as a technology savvy company, wanted to provide a platform to its employees where they could network socially, view and host microsites, stream live videos, blog and provide the latest news. The IT team at Verizon Wireless had abundant experience with various technology platforms to support the huge number of applications in the company. However, open-source products weren’t yet widely used in the organization and the team had the ambition to adopt such technologies and see if the architecture could meet Verizon Wireless’ rigid requirements. After evaluating a few solutions, the IT team decided to use the LAMP stack for Vzweb, its mission-critical, 24x7 employee portal, with Drupal as the front end and MySQL on Linux as the backend, and for a few other internal websites also on MySQL. The MySQL Solution Verizon Wireless started to support its employee portal, Vzweb, its online streaming website, Vztube, and internal wiki pages, Vzwiki, with MySQL 5.1 in 2010. Vzweb is the main internal communication channel for Verizon Wireless, while Vztube hosts important company-wide webcasts regularly for executive-level announcements, so both channels have to be live and accessible all the time for its 78,000 employees across the United States. However during the initial deployment of the MySQL based Intranet, the application experienced performance issues. High connection spikes occurred causing slow user response time, and the IT team applied workarounds to continue the service. A number of key performance indexes (KPI) for the infrastructure were identified and the operational framework redesigned to support a more robust website and conform to the 99.985% uptime SLA (Service-Level Agreement). The MySQL DBA team made a series of upgrades in MySQL: Step 1: Moved from MyISAM to InnoDB storage engine in 2010 Step 2: Upgraded to the latest MySQL 5.1.54 release in 2010 Step 3: Upgraded from MySQL 5.1 to the latest GA release MySQL 5.5 in 2011, and leveraging MySQL Thread Pool as part of MySQL Enterprise Edition to scale better After making those changes, the team saw a much better response time during high concurrency use cases, and achieved an amazing performance improvement of 1400%! In January 2011, Verizon CEO, Ivan Seidenberg, announced the iPhone launch during the opening keynote at Consumer Electronic Show (CES) in Las Vegas, and that presentation was streamed live to its 78,000 employees. The event was broadcasted flawlessly with MySQL as the database. Later in 2011, Hurricane Irene attacked the East Coast of United States and caused major life and financial damages. During the hurricane, the team directed more traffic to its west coast data center to avoid potential infrastructure damage in the East Coast. Such transition was executed smoothly and even though the geographical distance became longer for the East Coast users, there was no impact in the performance of Vzweb and Vztube, and the SLA goal was achieved. “MySQL is the key component of Verizon Wireless’ mission-critical employee portal application,” said Shivinder Singh, senior DBA at Verizon Wireless. “We achieved 1400% performance improvement by moving from the MyISAM storage engine to InnoDB, upgrading to the latest GA release MySQL 5.5, and using the MySQL Thread Pool to support high concurrent user connections. MySQL has become part of our IT infrastructure, on which potentially more future applications will be built.” To learn more about MySQL Enterprise Edition, Get our Product Guide.

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• A Graduate&rsquo;s Journey at Oracle &ndash; Bhaskar Ghosh From Oracle India

  - by david.talamelli

  I am Bhaskar Ghosh, and I work as an Applications Engineer with Oracle. Well, it was three years ago when my journey with one of the largest software companies started. It was a fine day and a decisive moment, when I was placed in Oracle as a campus recruit from College of Engineering Guindy, Anna University, Chennai! I always thought of looking back, the time that helped me learn beyond my boundaries, think broader and ahead, and grow – technically, professionally and personally. Hmmn! Let me recall the eventful moments once again. My first day as an intern at Oracle started in late 2007. I met one of the Oracle Managers at the Oracle Campus in Hyderabad and on the same day I also met another Oracle employee who was to later to become my first manager. I was charged and thrilled with the environment and the wonderful people around me! I was joined by two other interns, who also had a Masters in Computer Applications. We formed a very friendly group with all the interns and the new hires, and shared our excitement and learning. Myself and one of the other Graduates started working on a very interesting project on Semantic technology. We finally had our names added as co-developers for this very project. This phase of five months was the time and we learnt tremendously and worked very hard, partly because we had to travel back and forth to our colleges to submit reports and present for the Masters in Computer Applications final year project reviews. After completing my MCA, I joined as a full-time employee in 2008. During the next year, we worked on interesting and bleeding edge technologies - OWL, RDF, SPARQL, Visualization, J2EE, Social Web features, Semantic Web technologies, Web Services and many more! We developed cool, rich internet and desktop applications. Little did I know at that time, that this learning would help me tremendously for my the next project in Oracle. The following year saw me being assigned a role in a different project that my other team members were working on for the last two years. It took me two months to understand and get into a flow with this new task. I was fortunate that this phase helped me enhance my inter-personal and communication skills, as much as it helped me grow professionally with better ability to tackle multiple priorities and switch between tasks based on the team’s requirements. I was made the POC for all communications with our team and other product teams. I personally feel that this time enhanced me tremendously in technologies like Oracle Forms, J2EE, and Java and Web Services. The last six months, saw myself becoming an Institute of Electrical and Electronics Engineer member, and continuing my higher education International Institute of Information Technology, Hyderabad. Oracle supports its employees becoming members of professional bodies, and higher studies are supported by management, I think it is tremendously helpful in the professional and technical growth of the employees. Last three months, I have been working on great and useful enhancements to our product. Ah beautiful! All these years, there have been other moments and events of fun that are too worth mentioning. Clubs and groups at Oracle such as Employee Club, Oracle Volunteers, Football Club, etc. have always kept on organizing numerous events and competitions, full of fun and entertainment. I really enjoyed participating, even if it was small, in the intra-Oracle football tourney, Oracle Volunteer Days, OraFora, OraOvations, and a few more. Those ‘Seasons of Sharing’, those ‘Blood Donation camps’, those ‘Diwali and Christmas gifts and events’, those ‘fun events at the annual function called OraOvations’, those ‘books and cycle stalls’, and those so many other things… It only fills my mind with pleasure. The last three years have been very eventful:they have been full of learning and growth, and under the very able and encouraging guidance of my manager. I have got the opportunity to know about and/or interact with many wonderful personalities, and learn from them, here at Oracle. The environment, the people, and the fellow developers have been so friendly, and always ever ready to help, when we were in doubt.. I really love the big office space, and the flexible timings, and the caring people around. I look forward to a beautiful, learning and motivating journey with Oracle.

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• HDFC Bank's Journey to Oracle Private Database Cloud

  - by Nilesh Agrawal

  One of the key takeaways from a recent post by Sushil Kumar is the importance of business initiative that drives the transformational journey from legacy IT to enterprise private cloud. The journey that leads to a agile, self-service and efficient infrastructure with reduced complexity and enables IT to deliver services more closely aligned with business requirements. Nilanjay Bhattacharjee, AVP, IT of HDFC Bank presented a real-world case study based on one such initiative in his Oracle OpenWorld session titled "HDFC BANK Journey into Oracle Database Cloud with EM 12c DBaaS". The case study highlighted in this session is from HDFC Bank’s Lending Business Segment, which comprises roughly 50% of Bank’s top line. Bank’s Lending Business is always under pressure to launch “New Schemes” to compete and stay ahead in this segment and IT has to keep up with this challenging business requirement. Lending related applications are highly dynamic and go through constant changes and every single and minor change in each related application is required to be thoroughly UAT tested certified before they are certified for production rollout. This leads to a constant pressure in IT for rapid provisioning of UAT databases on an ongoing basis to enable faster time to market. Nilanjay joined Sushil Kumar, VP, Product Strategy, Oracle, during the Enterprise Manager general session at Oracle OpenWorld 2012. Let's watch what Nilanjay had to say about their recent Database cloud deployment. “Agility” in launching new business schemes became the key business driver for private database cloud adoption in the Bank. Nilanjay spent an hour discussing it during his session. Let's look at why Database-as-a-Service(DBaaS) model was need of the hour in this case  - Average 3 days to provision UAT Database for Loan Management Application Silo’ed UAT environment with Average 30% utilization Compliance requirement consume UAT testing resources DBA activities leads to $$ paid to SI for provisioning databases manually Overhead in managing configuration drift between production and test environments Rollout impact/delay on new business initiatives The private database cloud implementation progressed through 4 fundamental phases - Standardization, Consolidation, Automation, Optimization of UAT infrastructure. Project scoping was carried out and end users and stakeholders were engaged early on right from planning phase and including all phases of implementation. Standardization and Consolidation phase involved multiple iterations of planning to first standardize on infrastructure, db versions, patch levels, configuration, IT processes etc and with database level consolidation project onto Exadata platform. It was also decided to have existing AIX UAT DB landscape covered and EM 12c DBaaS solution being platform agnostic supported this model well. Automation and Optimization phase provided the necessary Agility, Self-Service and efficiency and this was made possible via EM 12c DBaaS. EM 12c DBaaS Self-Service/SSA Portal was setup with required zones, quotas, service templates, charge plan defined. There were 2 zones implemented - Exadata zone  primarily for UAT and benchmark testing for databases running on Exadata platform and second zone was for AIX setup to cover other databases those running on AIX. Metering and Chargeback/Showback capabilities provided business and IT the framework for cloud optimization and also visibility into cloud usage. More details on UAT cloud implementation, related building blocks and EM 12c DBaaS solution are covered in Nilanjay's OpenWorld session here. Some of the key Benefits achieved from UAT cloud initiative are - New business initiatives can be easily launched due to rapid provisioning of UAT Databases [ ~3 hours ] Drastically cut down $$ on SI for DBA Activities due to Self-Service Effective usage of infrastructure leading to  better ROI Empowering  consumers to provision database using Self-Service Control on project schedule with DB end date aligned to project plan submitted during provisioning Databases provisioned through Self-Service are monitored in EM and auto configured for Alerts and KPI Regulatory requirement of database does not impact existing project in queue This table below shows typical list of activities and tasks involved when a end user requests for a UAT database. EM 12c DBaaS solution helped reduce UAT database provisioning time from roughly 3 days down to 3 hours and this timing also includes provisioning time for database with production scale data (ranging from 250 G to 2 TB of data) - And it's not just about time to provision,  this initiative has enabled an agile, efficient and transparent UAT environment where end users are empowered with real control of cloud resources and IT's role is shifted as enabler of strategic services instead of being administrator of all user requests. The strong collaboration between IT and business community right from planning to implementation to go-live has played the key role in achieving this common goal of enterprise private cloud. Finally, real cloud is here and this cloud is accompanied with rain (business benefits) as well ! For more information, please go to Oracle Enterprise Manager  web page or  follow us at :  Twitter | Facebook | YouTube | Linkedin | Newsletter

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• Oracle Fusion Applications User Experience Design Patterns: Feeling the Love after Launch

  - by mvaughan

  By Misha Vaughan, Oracle Applications User ExperienceIn the first video by the Oracle Applications User Experience team on the Oracle Partner Network, Vice President Jeremy Ashley said that Oracle is looking to expand the ecosystem of support for Oracle’s applications customers as they begin to assess their investment and adoption of Oracle Fusion Applications. Oracle has made a massive investment to maintain the benefits of the Fusion Applications User Experience. This summer, the Applications User Experience team released the Oracle Fusion Applications user experience design patterns.Design patterns help create consistent experiences across devices.The launch has been very well received:Angelo Santagata, Senior Principal Technologist and Fusion Middleware evangelist for Oracle,  wrote this to the system integrator community: “The web site is the result of many years of Oracle R&D into user interface design for Fusion Applications and features a really cool web app which allows you to visualise the UI components in action.”  Grant Ronald, Director of Product Management, Application Development Framework (ADF) said: “It’s a science I don't understand, but now I don't have to ... Now you can learn from the UX experience of Fusion Applications.”Frank Nimphius, Senior Principal Product Manager, Oracle (ADF) wrote about the launch of the design patterns for the ADF Code Corner, and Jürgen Kress, Senior Manager EMEA Alliances & Channels for Fusion MiddleWare and Service Oriented Architecture, (SOA), shared the news with his Partner Community. Oracle Twitter followers also helped spread the message about the design patterns launch: ?@bex – Brian Huff, founder and Chief Software Architect for Bezzotech, and Oracle ACE Director:“Nifty! The Oracle Fusion UX team just released new ADF design patterns.”@maiko_rocha, Maiko Rocha, Oracle Consulting Solutions Architect and Oracle FMW engineer: “Haven't seen any other vendor offer such comprehensive UX Design Patterns catalog for free!”@zirous_chad, Chad Thompson, Senior Solutions Architect for Zirous, Inc. and ADF Developer:Wow - @ultan and company did a great job with the Fusion UX PatternsWhat is a user experience design pattern?A user experience design pattern is a re-usable, usability tested functional blueprint for a particular user experience.  Some examples are guided processes, shopping carts, and search and search results.  Ultan O’Broin discusses the top design patterns every developer should know.The patterns that were just released are based on thousands of hours of end-user field studies, state-of-the-art user interface assessments, and usability testing.  To be clear, these are functional design patterns, not technical design patterns that developers may be used to working with.  Because we know there is a gap, we are putting together some training that will help close that gap.Who should care?This is an offering targeted primarily at Application Development Framework (ADF) developers. If you are faced with the following questions regarding Fusion Applications, you will want to know and learn more:•    How do I build something that looks like Fusion Applications?•    How do I build a next-generation application?•    How do I extend a Fusion Application and maintain the user experience?•    I don’t want to re-invent the wheel on the user interface, so where do I start?•    I need to build something that will eventually co-exist with Fusion Applications. How do I do that?These questions are relevant to partners with an ADF competency, individual practitioners, or small consultancies with an ADF specialization, and customers who are trying to shift their IT staff over to supporting Fusion Applications.Where you can find out more?OnlineOur Fusion User Experience design patterns maven is Ultan O’Broin. The Oracle Partner Network is helping our team bring this first e-seminar to you in order to go into a more detail on what this means and how to take advantage of it:? Webinar: Build a Better User Experience with Oracle: Oracle Fusion Applications Functional Design PatternsSept 20, 2012 , 10:30am-11:30am PacificDial-In:  1. 877-664-9137 / Passcode 102546?International:  706-634-9619  http://www.intercall.com/national/oracleuniversity/gdnam.htmlAccess the Live Event Or Via Webconference Access http://ouweb.webex.com  ?and enter this session number: 598036234At a Usergroup eventThe Fusion User Experience Advocates (FXA) are also going to be getting some deep-dive training on this content and can share it with local user groups.At OpenWorld Ultan O’Broin               Chris MuirIf you will be at OpenWorld this year, our own Ultan O’Broin will be visiting the ADF demopod to say hello, thanks to Shay Shmeltzer, Senior Group Manager for ADF outbound communication and at the OTN lounge: Monday 10-10:45, Tuesday 2:15-2:45, Wednesday 2:15-3:30 ?  Oracle JDeveloper and Oracle ADF,  Moscone South, Right - S-207? “ADF Meet and Greett”, OTN Lounge, Wednesday 4:30 And I cannot talk about OpenWorld and ADF without mentioning Chris Muir’s ADF EMG event: the Year After the Year Of the ADF Developer – Sunday, Sept 30 of OpenWorld. Chris has played host to Ultan and the Applications user experience message for his online community and is now a seasoned UX expert.Expect to see additional announcements about expanded and training on similar topics in the future.

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• JavaOne pictures and Community Commentary on JCP Awards

  - by heathervc

  We posted some pictures from JCP related events at JavaOne 2012 on the JCP Facebook page today.  The 2012 JCP Program Award winners and some of the nominees responded to the community recognition of their achievements during some of the JCP events last week.     “Our job on the EC is to balance the need of innovation – so we don’t standardize too early, or too late. We try to find that sweet spot that makes innovation and standardization work together, and not against each other.”- Ben Evans, CEO of jClarity and Executive Committee (EC) representative of the London Java Community, 2012 JCP Member/Participant of the Year Winner“SouJava has been evangelizing the Java platform, promoting the Java ecosystem in Brazil, and contributing to JSRs for several years. It’s very gratifying to have our work recognized, on behalf of many developers and Java User Groups around the world. This really is the work of a large group of people, represented by the few that can be here tonight.”- Michael Santos, representative of SouJava, 2012 JCP Member/Participant of the Year Winner "In the last years Credit Suisse has contributed to the development of Java EE specifications through participation in many customer advisory boards, through statements of requirements for extensions to the core Java related products in use, and active participation in JSRs. Winning the JCP Outstanding Spec Lead Award 2012 is very encouraging for our engagement and also demonstrates the level of expertise and commitment to drive the evolution of Java. Victor Grazi is happy and honored to receive this award." - Susanne Cech Previtali, Executive Committee (EC) representative of Credit Suisse, accepting award for 2012 JCP Outstanding Spec Lead Winner "Managing a JSR is difficult. There are so many decisions to be made and so many good and varied opinions, you never really know if you have decided correctly. The key to success is transparency and collaboration. I am truly humbled by receiving this award, there are so many other active JSRs.” Victor added that going forward in the JCP EC, they would like to simplify and open the process of participation – being addressed in the JCP.Next initiative of the JCP EC. "We would also like to encourage the engagement of universities, professors and students – as an important part of the Java community. While innovation is the lifeblood of our community and industry, without strong standards and compatibility requirements, we all end up in a maze of technology where everything is slightly different and doesn’t quite work with everything else." Victo Grazi, Executive Committee (EC) representative of Credit Suisse, 2012 JCP Outstanding Spec Lead Winner“I am very pleased, of course, to accept this award, but the credit really should go to all of those who have participated in the work of the JCP, while pushing for changes in the way it operates.  JCP.Next represents three JSRs. The first two are done, but the final step, JSR 358, is the complicated one, and it will bring in the lawyers. Just to give you an idea of what we’re dealing with, it affects licensing, intellectual property, patents, implementations not based on the Reference Implementation (RI), the role of the RI, compatibility policy, possible changes to the Technical Compatibility Kit (TCK), transparency, where do individuals fit in, open source, and more.”- Patrick Curran, JCP Chair, Spec Lead on JCP.Next JSRs (JSR 348, JSR 355 and JSR 358), 2012 JCP Most Significant JSR Winner“I’m especially glad to see the JCP community recognize JCP.Next for its importance. The governance work it represents is KEY to moving the Java platform forward and the success of the technology.”- John Rizzo, Executive Committee (EC) representative of Aplix Corporation, JSR Expert Group Member “I am deeply honored to be nominated. I had the privilege to receive two awards on behalf of Expert Groups and Spec Leads two years ago. But this time, I am nominated personally, which values my own contribution to the JCP, and of course, participation in JSRs and the EC work. I’m a fan of Agile Principles and Values Working. Being an Agile Coach and Consultant, I use it for some of the biggest EC Member companies and projects. It fuels my ability to help the JCP become more agile, lean and transparent as part of the JCP.Next effort.” - Werner Keil, Individual Executive Committee (EC) Member, a 2012 JCP Member/Participant of the Year Nominee, JSR Expert Group Member“The JCP ever has been some kind of institution for me,” Markus said. “If in technical doubt, I go there, look for the specifications of the implementation I work with at the moment and verify what I had observed. Since the beginning of my Java journey more than 12 years back now, I always had a strong relationship with the JCP. Shaping the future of a technology by joining the JCP – giving feedback and contributing to the road ahead through individual JSRs – that brings you to a whole new level.”Calling himself, “the new kid on the block,” he explained that for years he was afraid to join the JCP and contribute. But in reality, “Every single one of the big names I meet from the different Expert Groups is a nice person. People you can actually work with,” he says. “And nobody blames you for things you don't know. As long as you are committed and bring what is worth the most: passion, experiences and the desire to make a difference.” - Markus Eisele, a 2012 JCP Member of the Year Nominee, JSR Expert Group MemberCongratulations again to all of the nominees and winners of the JCP Program Awards.  Next year, we will add another award for the group of JUG members (not an entire JUG) that makes the best contribution to the Adopt-a-JSR program.  Let us know if you have other suggestions or improvements.

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• ASP.NET Web API - Screencast series Part 4: Paging and Querying

  - by Jon Galloway

  We're continuing a six part series on ASP.NET Web API that accompanies the getting started screencast series. This is an introductory screencast series that walks through from File / New Project to some more advanced scenarios like Custom Validation and Authorization. The screencast videos are all short (3-5 minutes) and the sample code for the series is both available for download and browsable online. I did the screencasts, but the samples were written by the ASP.NET Web API team. In Part 1 we looked at what ASP.NET Web API is, why you'd care, did the File / New Project thing, and did some basic HTTP testing using browser F12 developer tools. In Part 2 we started to build up a sample that returns data from a repository in JSON format via GET methods. In Part 3, we modified data on the server using DELETE and POST methods. In Part 4, we'll extend on our simple querying methods form Part 2, adding in support for paging and querying. This part shows two approaches to querying data (paging really just being a specific querying case) - you can do it yourself using parameters passed in via querystring (as well as headers, other route parameters, cookies, etc.). You're welcome to do that if you'd like. What I think is more interesting here is that Web API actions that return IQueryable automatically support OData query syntax, making it really easy to support some common query use cases like paging and filtering. A few important things to note: This is just support for OData query syntax - you're not getting back data in OData format. The screencast demonstrates this by showing the GET methods are continuing to return the same JSON they did previously. So you don't have to "buy in" to the whole OData thing, you're just able to use the query syntax if you'd like. This isn't full OData query support - full OData query syntax includes a lot of operations and features - but it is a pretty good subset: filter, orderby, skip, and top. All you have to do to enable this OData query syntax is return an IQueryable rather than an IEnumerable. Often, that could be as simple as using the AsQueryable() extension method on your IEnumerable. Query composition support lets you layer queries intelligently. If, for instance, you had an action that showed products by category using a query in your repository, you could also support paging on top of that. The result is an expression tree that's evaluated on-demand and includes both the Web API query and the underlying query. So with all those bullet points and big words, you'd think this would be hard to hook up. Nope, all I did was change the return type from IEnumerable<Comment> to IQueryable<Comment> and convert the Get() method's IEnumerable result using the .AsQueryable() extension method. public IQueryable<Comment> GetComments() { return repository.Get().AsQueryable(); } You still need to build up the query to provide the $top and $skip on the client, but you'd need to do that regardless. Here's how that looks: $(function () { //--------------------------------------------------------- // Using Queryable to page //--------------------------------------------------------- $("#getCommentsQueryable").click(function () { viewModel.comments([]); var pageSize = $('#pageSize').val(); var pageIndex = $('#pageIndex').val(); var url = "/api/comments?$top=" + pageSize + '&$skip=' + (pageIndex * pageSize); $.getJSON(url, function (data) { // Update the Knockout model (and thus the UI) with the comments received back // from the Web API call. viewModel.comments(data); }); return false; }); }); And the neat thing is that - without any modification to our server-side code - we can modify the above jQuery call to request the comments be sorted by author: $(function () { //--------------------------------------------------------- // Using Queryable to page //--------------------------------------------------------- $("#getCommentsQueryable").click(function () { viewModel.comments([]); var pageSize = $('#pageSize').val(); var pageIndex = $('#pageIndex').val(); var url = "/api/comments?$top=" + pageSize + '&$skip=' + (pageIndex * pageSize) + '&$orderby=Author'; $.getJSON(url, function (data) { // Update the Knockout model (and thus the UI) with the comments received back // from the Web API call. viewModel.comments(data); }); return false; }); }); So if you want to make use of OData query syntax, you can. If you don't like it, you're free to hook up your filtering and paging however you think is best. Neat. In Part 5, we'll add on support for Data Annotation based validation using an Action Filter.

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• Passing the CAML thru the EY of the NEEDL

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved Passing the CAML thru the EY of the NEEDL Definitions: CAML (Collaborative Application Markup Language) is an XML based markup language used in Microsoft SharePoint technologies  Anonymous: A camel is a horse designed by committee  Dov Trietsch: A CAML is a HORS designed by Microsoft  I was advised against putting any Camel and Sphinx rhymes in here. Look it up in Google!  _____ Now that we have dispensed with the dromedary jokes (BTW, I have many more, but they are not fit to print!), here is an interesting problem and its solution.  We have built a list where the title must be kept unique so I needed to verify the existence (or absence) of a list item with a particular title. Two methods came to mind:  1: Span the list until the title is found (result = found) or until the list ends (result = not found). This is an algorithm of complexity O(N) and for long lists it is a performance sucker. 2: Use a CAML query instead. Here, for short list we’ll encounter some overhead, but because the query results in an SQL query on the content database, it is of complexity O(LogN), which is significantly better and scales perfectly. Obviously I decided to go with the latter and this is where the CAML s--t hit the fan.   A CAML query returns a SPListItemCollection and I simply checked its Count. If it was 0, the item did not already exist and it was safe to add a new item with the given title. Otherwise I cancelled the operation and warned the user. The trouble was that I always got a positive. Most of the time a false positive. The count was greater than 0 regardles of the title I checked (except when the list was empty, which happens only once). This was very disturbing indeed. To solve my immediate problem which was speedy delivery, I reverted to the “Span the list” approach, but the problem bugged me, so I wrote a little console app by which I tested and tweaked and tested, time and again, until I found the solution. Yes, one can pass the proverbial CAML thru the ey of the needle (e’s missing on purpose).  So here are my conclusions:  CAML that does not work:  Note: QT is my quote:  char QT = Convert.ToChar((int)34); string titleQuery = "<Query>><Where><Eq>"; titleQuery += "<FieldRef Name=" + QT + "Title" + QT + "/>"; titleQuery += "<Value Type=" + QT + "Text" + QT + ">" + uniqueID + "</Value></Eq></Where></Query>"; titleQuery += "<ViewFields><FieldRef Name=" + QT + "Title" + QT + "/></ViewFields>";  Why? Even though U2U generates it, the <Query> and </Query> tags do not belong in the query that you pass. Start your query with the <Where> clause.  Also the <ViewFiels> clause does not belong. I used this clause to limit the returned collection to a single column, and I still wish to do it. I’ll show how this is done a bit later.   When you use the <Query> </Query> tags in you query, it’s as if you did not specify the query at all. What you get is the all inclusive default query for the list. It returns evey column and every item. It is expensive for both server and network because it does all the extra processing and eats plenty of bandwidth.   Now, here is the CAML that works  string titleQuery = "<Where><Eq>"; titleQuery += "<FieldRef Name=" + QT + "Title" + QT + "/>"; titleQuery += "<Value Type=" + QT + "Text" + QT + ">" + uniqueID + "</Value></Eq></Where>";  You’ll also notice that inside the unusable <ViewFields> clause above, we have a <FieldRef> clause. This is what we pass to the SPQuery object. Here is how:  SPQuery query = new SPQuery(); query.Query = titleQuery; query.ViewFields = "<FieldRef Name=" + QT + "Title" + QT + "/>"; query.RowLimit = 1; SPListItemCollection col = masterList.GetItems(query);  Two thing to note: we enter the view fields into the SPQuery object and we also limited the number of rows that the query returns. The latter is not always done, but in an existence test, there is no point in returning hundreds of rows. The query will now return one item or none, which is all we need in order to verify the existence (or non-existence) of items. Limiting the number of columns and the number of rows is a great performance enhancer. That’s all folks!!

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• Implementing an Interceptor Using NHibernate’s Built In Dynamic Proxy Generator

  - by Ricardo Peres

  NHibernate 3.2 came with an included proxy generator, which means there is no longer the need – or the possibility, for that matter – to choose Castle DynamicProxy, LinFu or Spring. This is actually a good thing, because it means one less assembly to deploy. Apparently, this generator was based, at least partially, on LinFu. As there are not many tutorials out there demonstrating it’s usage, here’s one, for demonstrating one of the most requested features: implementing INotifyPropertyChanged. This interceptor, of course, will still feature all of NHibernate’s functionalities that you are used to, such as lazy loading, and such. We will start by implementing an NHibernate interceptor, by inheriting from the base class NHibernate.EmptyInterceptor. This class does not do anything by itself, but it allows us to plug in behavior by overriding some of its methods, in this case, Instantiate: 1: public class NotifyPropertyChangedInterceptor : EmptyInterceptor 2: { 3: private ISession session = null; 4:  5: private static readonly ProxyFactory factory = new ProxyFactory(); 6:  7: public override void SetSession(ISession session) 8: { 9: this.session = session; 10: base.SetSession(session); 11: } 12:  13: public override Object Instantiate(String clazz, EntityMode entityMode, Object id) 14: { 15: Type entityType = Type.GetType(clazz); 16: IProxy proxy = factory.CreateProxy(entityType, new _NotifyPropertyChangedInterceptor(), typeof(INotifyPropertyChanged)) as IProxy; 17: 18: _NotifyPropertyChangedInterceptor interceptor = proxy.Interceptor as _NotifyPropertyChangedInterceptor; 19: interceptor.Proxy = this.session.SessionFactory.GetClassMetadata(entityType).Instantiate(id, entityMode); 20:  21: this.session.SessionFactory.GetClassMetadata(entityType).SetIdentifier(proxy, id, entityMode); 22:  23: return (proxy); 24: } 25: } Then we need a class that implements the NHibernate dynamic proxy behavior, let’s place it inside our interceptor, because it will only need to be used there: 1: class _NotifyPropertyChangedInterceptor : NHibernate.Proxy.DynamicProxy.IInterceptor 2: { 3: private PropertyChangedEventHandler changed = delegate { }; 4:  5: public Object Proxy 6: { 7: get; 8: set;} 9:  10: #region IInterceptor Members 11:  12: public Object Intercept(InvocationInfo info) 13: { 14: Boolean isSetter = info.TargetMethod.Name.StartsWith("set_") == true; 15: Object result = null; 16:  17: if (info.TargetMethod.Name == "add_PropertyChanged") 18: { 19: PropertyChangedEventHandler propertyChangedEventHandler = info.Arguments[0] as PropertyChangedEventHandler; 20: this.changed += propertyChangedEventHandler; 21: } 22: else if (info.TargetMethod.Name == "remove_PropertyChanged") 23: { 24: PropertyChangedEventHandler propertyChangedEventHandler = info.Arguments[0] as PropertyChangedEventHandler; 25: this.changed -= propertyChangedEventHandler; 26: } 27: else 28: { 29: result = info.TargetMethod.Invoke(this.Proxy, info.Arguments); 30: } 31:  32: if (isSetter == true) 33: { 34: String propertyName = info.TargetMethod.Name.Substring("set_".Length); 35: this.changed(this.Proxy, new PropertyChangedEventArgs(propertyName)); 36: } 37:  38: return (result); 39: } 40:  41: #endregion 42: } What this does for every interceptable method (those who are either virtual or from the INotifyPropertyChanged) is: For methods that came from the INotifyPropertyChanged interface, add_PropertyChanged and remove_PropertyChanged (yes, events are methods ), we add an implementation that adds or removes the event handlers to the delegate which we declared as changed; For all the others, we direct them to the place where they are actually implemented, which is the Proxy field; If the call is setting a property, it fires afterwards the PropertyChanged event. In order to use this, we need to add the interceptor to the Configuration before building the ISessionFactory: 1: using (ISessionFactory factory = cfg.SetInterceptor(new NotifyPropertyChangedInterceptor()).BuildSessionFactory()) 2: { 3: using (ISession session = factory.OpenSession()) 4: using (ITransaction tx = session.BeginTransaction()) 5: { 6: Customer customer = session.Get<Customer>(100); //some id 7: INotifyPropertyChanged inpc = customer as INotifyPropertyChanged; 8: inpc.PropertyChanged += delegate(Object sender, PropertyChangedEventArgs e) 9: { 10: //fired when a property changes 11: }; 12: customer.Address = "some other address"; //will raise PropertyChanged 13: customer.RecentOrders.ToList(); //will trigger the lazy loading 14: } 15: } Any problems, questions, do drop me a line!

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• Oracle Database 12c Spatial: Vector Performance Acceleration

  - by Okcan Yasin Saygili-Oracle

  Most business information has a location component, such as customer addresses, sales territories and physical assets. Businesses can take advantage of their geographic information by incorporating location analysis and intelligence into their information systems. This allows organizations to make better decisions, respond to customers more effectively, and reduce operational costs – increasing ROI and creating competitive advantage. Oracle Database, the industry’s most advanced database,  includes native location capabilities, fully integrated in the kernel, for fast, scalable, reliable and secure spatial and massive graph applications. It is a foundation for deploying enterprise-wide spatial information systems and locationenabled business applications. Developers can extend existing Oracle-based tools and applications, since they can easily incorporate location information directly in their applications, workflows, and services. Spatial Features The geospatial data features of Oracle Spatial and Graph option support complex geographic information systems (GIS) applications, enterprise applications and location services applications. Oracle Spatial and Graph option extends the spatial query and analysis features included in every edition of Oracle Database with the Oracle Locator feature, and provides a robust foundation for applications that require advanced spatial analysis and processing in the Oracle Database. It supports all major spatial data types and models, addressing challenging business-critical requirements from various industries, including transportation, utilities, energy, public sector, defense and commercial location intelligence. Network Data Model Graph Features The Network Data Model graph explicitly stores and maintains a persistent data model withnetwork connectivity and provides network analysis capability such as shortest path, nearest neighbors, within cost and reachability. It loads partitioned networks into memory on demand, overcomingthe limitations of in-memory analysis. Partitioning massive networks into manageable sub-networkssimplifies the network analysis. RDF Semantic Graph Features RDF Semantic Graph has native support for World Wide Web Consortium standards. It has open, scalable, and secure features for storing RDF/OWL ontologies anddata; native inference with OWL 2, SKOS and user-defined rules; and querying RDF/OWL data withSPARQL 1.1, Java APIs, and SPARQLgraph patterns in SQL. Video: Oracle Spatial and Graph Overview Oracle spatial is embeded on oracle database product. So ,we can use oracle installer (OUI).The Oracle Universal Installer (OUI) is used to install Oracle Database software. OUI is a graphical user interface utility that enables you to view the Oracle software that is installed on your machine, install new Oracle Database software, and delete Oracle software that you no longer need to use. Online Help is available to guide you through the installation process. One of the installation options is to create a database. If you select database creation, OUI automatically starts Oracle Database Configuration Assistant (DBCA) to guide you through the process of creating and configuring a database. If you do not create a database during installation, you must invoke DBCA after you have installed the software to create a database. You can also use DBCA to create additional databases. For installing Oracle Database 12c you may check the Installing Oracle Database Software and Creating a Database tutorial under the Oracle Database 12c 2-Day DBA Series.You can always check if spatial is available in your database using  "select comp_id, version, status, comp_name from dba_registry where comp_id='SDO';"   One of the most notable improvements with Oracle Spatial and Graph 12c can be seen in performance increases in vector data operations. Enabling the Spatial Vector Acceleration feature (available with the Spatial option) dramatically improves the performance of commonly used vector data operations, such as sdo_distance, sdo_aggr_union, and sdo_inside. With 12c, these operations also run more efficiently in parallel than in prior versions through the use of metadata caching. For organizations that have been facing processing limitations, these enhancements enable developers to make a small set of configuration changes and quickly realize significant performance improvements. Results include improved index performance, enhanced geometry engine performance, optimized secondary filter optimizations for Spatial operators, and improved CPU and memory utilization for many advanced vector functions. Vector performance acceleration is especially beneficial when using Oracle Exadata Database Machine and other large-scale systems. Oracle Spatial and Graph vector performance acceleration builds on general improvements available to all SDO_GEOMETRY operations in these areas: Caching of index metadata, Concurrent update mechanisms, and Optimized spatial predicate selectivity and cost functions. These optimizations enable more efficient use of: CPU, Memory, and Partitioning Resulting in substantial query performance improvements.UsageTo accelerate the performance of spatial operators, it is recommended that you set the SPATIAL_VECTOR_ACCELERATION database system parameter to the value TRUE. (This parameter is authorized for use only by licensed Oracle Spatial users, and its default value is FALSE.) You can set this parameter for the whole system or for a single session. To set the value for the whole system, do either of the following:Enter the following statement from a suitably privileged account:   ALTER SYSTEM SET SPATIAL_VECTOR_ACCELERATION = TRUE;Add the following to the database initialization file (xxxinit.ora):   SPATIAL_VECTOR_ACCELERATION = TRUE;To set the value for the current session, enter the following statement from a suitably privileged account:   ALTER SESSION SET SPATIAL_VECTOR_ACCELERATION = TRUE; Checkout the complete list of new features on Oracle.com @ http://www.oracle.com/technetwork/database/options/spatialandgraph/overview/index.html Spatial and Graph Data Sheet (PDF) Spatial and Graph White Paper (PDF)

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• User Experience Fundamentals

  - by ultan o'broin

  Understanding what user experience means in the modern work environment is central to building great-looking usable applications on the desktop or mobile devices. What better place to start a series of blog posts on such Applications User Experience team enablement for customers and partners than by sharing what the term really means, writes team member Karen Scipi. Applications UX have gained valuable insights into developing a user experience that reflects the experience of today’s worker. We have observed real workers performing real tasks in real work environments, and we have developed a set of new standards of application design that have been scientifically proven to be beneficial to enable today’s workers. We share such expertise to enable our customers and partners to benefit from our insights and to further their return on investment when building Oracle applications. So, What is User Experience? ?The user interface (UI) is about the on-screen user context provided by the layout of widgets (such as icons, fields, and buttons and more) and the visual impact of colors, typographic choices, and so on. The UI comprises the “look and feel” of the application that users interact with, and reflects, in essence, the most immediate aspects of usability we can now all relate to.  User experience, on the other hand, is about understanding the whole context of the world of work, how workers go about completing tasks, crossing all sorts of boundaries along the way. It is a study of how business processes and workers goals coincide, how users work with technology or other tools to get their jobs done, their interactions with other users, and their response to the technical, physical, and cultural environment around them. User experience is all about how users work—their work environments, office layouts, desk tools, types of devices, their working day, and more. Even their job aids, such as sticky notes, offer insight for UX innovation. User experience matters because businesses needs to be efficient, work must be productive, and users now demand to be satisfied by the applications they work with. In simple terms, tasks finished quickly and accurately for a business evokes organization and worker satisfaction, which in turn makes workers feel good and more than willing to use the application again tomorrow. Design Principles for the Enterprise Worker The consumerization of information technology has raised the bar for enterprise applications. Applications must be consistent, simple, intuitive, but above all contextual, reflecting how and when workers work, in the office or on the go. For example, the Google search experience with its type-ahead keyword-prompting feature is how workers expect to be able to discover enterprise information, too. Type-ahead in PeopleSoft 9.1 To build software that enables workers to be productive, our design principles meet modern work requirements about consistency, with well-organized, context-driven information, geared for a working world of discovery and collaboration. Our applications must also behave in a simple, web-like way just like Amazon, Google, and Apple products that workers use at home or on the go. Our user experience must also reflect workers’ needs for flexibility and well-loved enterprise practices such as using popular desktop tools like Microsoft Excel or Outlook as required. Building User Experience Productively The building blocks of Oracle Fusion Applications are the user experience design patterns. Based on the Oracle Fusion Middleware technology used to build Oracle Fusion Applications, the patterns are reusable solutions to common usability challenges that ADF developers typically face as they build applications, extensions, and integrations. Developers use the patterns as part of their Oracle toolkits to realize great usability consistently and in a productive way. Our design pattern creation process is informed by user experience research and science, an understanding of our technology’s capabilities, the demands for simplification and intuitiveness from users, and the best of Oracle’s acquisitions strategy (an injection of smart people and smart innovation). The patterns are supported by usage guidelines and are tested in our labs and assembled into a library of proven resources we used to build own Oracle Fusion Applications and other Oracle applications user experiences. The design patterns library is now available to the ADF community and to our partners and customers, for free. Developers with ADF skills and other technology skills can now offer more than just coding and functionality and still use the best in enterprise methodologies to ensure that a great user experience is easily applied, scaled, and maintained, whether it be for SaaS or on-premise deployments for Oracle Fusion Applications, for applications coexistence, or for partner integrations scenarios.  Oracle partners and customers already using our design patterns to build solutions and win business in smart and productive ways are now sharing their experiences and insights on pattern use to benefit your entire business. Applications UX is going global with the message and the means. Our hands-on user experience enablement through ADF  is expanding. So, stay tuned to Misha Vaughan's Voice of User Experience (VOX) blog and follow along on Twitter at @usableapps for news of outreach events and other learning opportunities. Interested in Learning More? Oracle Fusion Applications User Experience Patterns and Guidelines Library Shout-outs for Oracle UX Design Patterns Oracle Fusion Applications User Experience Design Patterns: Productivity Realized

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• RTS Voxel Engine using LWJGL - Textures glitching

  - by Dieter Hubau

  I'm currently working on an RTS game engine using voxels. I have implemented a basic chunk manager using an Octree of Octrees which contains my voxels (simple square blocks, as in Minecraft). I'm using a Voronoi-based terrain generation to get a simplistic yet relatively realistic heightmap. I have no problem showing a 256*256*256 grid of voxels with a decent framerate (250), because of frustum culling, face culling and only rendering visible blocks. For example, in a random voxel grid of 256*256*256 I generally only render 100k-120k faces, not counting frustum culling. Frustum culling is only called every 100ms, since calling it every frame seemed a bit overkill. Now I have reached the stage of texturing and I'm experiencing some problems: Some experienced people might already see the problem, but if we zoom in, you can see the glitches more clearly: All the seams between my blocks are glitching and kind of 'overlapping' or something. It's much more visible when you're moving around. I'm using a single, simple texture map to draw on my cubes, where each texture is 16*16 pixels big: I have added black edges around the textures to get a kind of cellshaded look, I think it's cool. The texture map has 256 textures of each 16*16 pixels, meaning the total size of my texture map is 256*256 pixels. The code to update the ChunkManager: public void update(ChunkManager chunkManager) { for (Octree<Cube> chunk : chunks) { if (chunk.getId() < 0) { // generate an id for the chunk to be able to call it later chunk.setId(glGenLists(1)); } glNewList(chunk.getId(), GL_COMPILE); glBegin(GL_QUADS); faces += renderChunk(chunk); glEnd(); glEndList(); } } Where my renderChunk method is: private int renderChunk(Octree<Cube> node) { // keep track of the number of visible faces in this chunk int faces = 0; if (!node.isEmpty()) { if (node.isLeaf()) { faces += renderItem(node); } List<Octree<Cube>> children = node.getChildren(); if (children != null && !children.isEmpty()) { for (Octree<Cube> child : children) { faces += renderChunk(child); } } return faces; } Where my renderItem method is the following: private int renderItem(Octree<Cube> node) { Cube cube = node.getItem(-1, -1, -1); int faces = 0; float x = node.getPosition().x; float y = node.getPosition().y; float z = node.getPosition().z; float size = cube.getSize(); Vector3f point1 = new Vector3f(-size + x, -size + y, size + z); Vector3f point2 = new Vector3f(-size + x, size + y, size + z); Vector3f point3 = new Vector3f(size + x, size + y, size + z); Vector3f point4 = new Vector3f(size + x, -size + y, size + z); Vector3f point5 = new Vector3f(-size + x, -size + y, -size + z); Vector3f point6 = new Vector3f(-size + x, size + y, -size + z); Vector3f point7 = new Vector3f(size + x, size + y, -size + z); Vector3f point8 = new Vector3f(size + x, -size + y, -size + z); TextureCoordinates tc = textureManager.getTextureCoordinates(cube.getCubeType()); // front face if (cube.isVisible(CubeSide.FRONT)) { faces++; glTexCoord2f(TEXTURE_U_COORDINATES[tc.u], TEXTURE_V_COORDINATES[tc.v]); glVertex3f(point1.x, point1.y, point1.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u + 1], TEXTURE_V_COORDINATES[tc.v]); glVertex3f(point4.x, point4.y, point4.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u + 1], TEXTURE_V_COORDINATES[tc.v + 1]); glVertex3f(point3.x, point3.y, point3.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u], TEXTURE_V_COORDINATES[tc.v + 1]); glVertex3f(point2.x, point2.y, point2.z); } // back face if (cube.isVisible(CubeSide.BACK)) { faces++; glTexCoord2f(TEXTURE_U_COORDINATES[tc.u + 1], TEXTURE_V_COORDINATES[tc.v]); glVertex3f(point5.x, point5.y, point5.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u + 1], TEXTURE_V_COORDINATES[tc.v + 1]); glVertex3f(point6.x, point6.y, point6.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u], TEXTURE_V_COORDINATES[tc.v + 1]); glVertex3f(point7.x, point7.y, point7.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u], TEXTURE_V_COORDINATES[tc.v]); glVertex3f(point8.x, point8.y, point8.z); } // left face if (cube.isVisible(CubeSide.SIDE_LEFT)) { faces++; glTexCoord2f(TEXTURE_U_COORDINATES[tc.u], TEXTURE_V_COORDINATES[tc.v]); glVertex3f(point5.x, point5.y, point5.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u + 1], TEXTURE_V_COORDINATES[tc.v]); glVertex3f(point1.x, point1.y, point1.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u + 1], TEXTURE_V_COORDINATES[tc.v + 1]); glVertex3f(point2.x, point2.y, point2.z); glTexCoord2f(TEXTURE_U_COORDINATES[tc.u], TEXTURE_V_COORDINATES[tc.v + 1]); glVertex3f(point6.x, point6.y, point6.z); } // ETC ETC return faces; } When all this is done, I simply render my lists every frame, like this: public void render(ChunkManager chunkManager) { glBindTexture(GL_TEXTURE_2D, textureManager.getCubeTextureId()); // load all chunks from the tree List<Octree<Cube>> chunks = chunkManager.getTree().getAllItems(); for (Octree<Cube> chunk : chunks) { if (frustum.cubeInFrustum(chunk.getPosition(), chunk.getSize() / 2)) { glCallList(chunk.getId()); } } } I don't know if anyone is willing to go through all of this code or maybe you can spot the problem right away, but that is basically the problem, and I can't find a solution :-) Thanks for reading and any help is appreciated!

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• ASP.NET Web Forms Extensibility: Control Adapters

  - by Ricardo Peres

  All ASP.NET controls from version 2.0 can be associated with a control adapter. A control adapter is a class that inherits from ControlAdapter and it has the chance to interact with the control(s) it is targeting so as to change some of its properties or alter its output. I talked about control adapters before and they really a cool feature. The ControlAdapter class exposes virtual methods for some well known lifecycle events, OnInit, OnLoad, OnPreRender and OnUnload that closely match their Control counterparts, but are fired before them. Because the control adapter has a reference to its target Control, it can cast it to its concrete class and do something with it before its lifecycle events are actually fired. The adapter is also notified before the control is rendered (BeginRender), after their children are renderes (RenderChildren) and after itself is rendered (Render): this way the adapter can modify the control’s output. Control adapters may be specified for any class inheriting from Control, including abstract classes, web server controls and even pages. You can, for example, specify a control adapter for the WebControl and UserControl classes, but, curiously, not for Control itself. When specifying a control adapter for a page, it must inherit from PageAdapter instead of ControlAdapter. The adapter for a control, if specified, can be found on the protected Adapter property, and for a page, on the PageAdapter property. The first use of control adapters that came to my attention was for changing the output of standard ASP.NET web controls so that they were more based on CSS and less on HTML tables: it was the CSS Friendly Control Adapters project, now available at http://code.google.com/p/aspnetcontroladapters/. They are interesting because you specify them in one location and they apply anywhere a control of the target type is created. Mind you, it applies to controls declared on markup as well as controls created by code with the new operator. So, how do you use control adapters? The most usual way is through a browser definition file. In it, you specify a set of control adapters and their target controls, for a given browser. This browser definition file is a XML file with extension .Browser, and can either be global (%WINDIR%\Microsoft.NET\Framework64\vXXXX\Config\Browsers) or local to the web application, in which case, it must be placed inside the App_Browsers folder at the root of the web site. It looks like this: 1: <browsers> 2: <browser refID="Default"> 3: <controlAdapters> 4: <adapter controlType="System.Web.UI.WebControls.TextBox" adapterType="MyNamespace.TextBoxAdapter, MyAssembly" /> 5: </controlAdapters> 6: </browser> 7: </browsers> A browser definition file targets a specific browser, so you can have different definitions for Chrome, IE, Firefox, Opera, as well as for specific version of each of those (like IE8, Firefox3). Alternatively, if you set the target to Default, it will apply to all. The reason to pick a specific browser and version might be, for example, in order to circumvent some limitation present in that specific version, so that on markup you don’t need to be concerned with that. Another option is through the the current Browser object of the request: 1: this.Context.Request.Browser.Adapters.Add(typeof(TextBox).FullName, typeof(TextBoxAdapter).FullName); This must go very early on the page lifecycle, for example, on the OnPreInit event, or even on Application_Start. You have to specify the full class name for both the target control and the adapter. Of course, you have to do this for every request, because it won’t be persisted. As an example, you may know that the classic TextBox control renders an HTML input tag if its TextMode is set to SingleLine and a textarea if set to MultiLine. Because the textarea has no notion of maximum length, unlike the input, something must be done in order to enforce this. Here’s a simple suggestion: 1: public class TextBoxControlAdapter : ControlAdapter 2: { 3: protected TextBox Target 4: { 5: get 6: { 7: return (this.Control as TextBox); 8: } 9: } 10:  11: protected override void OnLoad(EventArgs e) 12: { 13: if ((this.Target.MaxLength > 0) && (this.Target.TextMode == TextBoxMode.MultiLine)) 14: { 15: if (this.Target.Page.ClientScript.IsClientScriptBlockRegistered("TextBox_KeyUp") == false) 16: { 17: if (this.Target.Page.ClientScript.IsClientScriptBlockRegistered(this.Target.Page.GetType(), "TextBox_KeyUp") == false) 18: { 19: String script = String.Concat("function TextBox_KeyUp(sender) { if (sender.value.length > ", this.Target.MaxLength, ") { sender.value = sender.value.substr(0, ", this.Target.MaxLength, "); } }\n"); 20:  21: this.Target.Page.ClientScript.RegisterClientScriptBlock(this.Target.Page.GetType(), "TextBox_KeyUp", script, true); 22: } 23:  24: this.Target.Attributes["onkeyup"] = "TextBox_KeyUp(this)"; 25: } 26: } 27: 28: base.OnLoad(e); 29: } 30: } What it does is, for every TextBox control, if it is set for multi line and has a defined maximum length, it injects some JavaScript that will filter out any content that exceeds this maximum length. This will occur for any TextBox that you may have on your site, or any class that inherits from it. You can use any of the previous options to register this adapter. Stay tuned for more ASP.NET Web Forms extensibility tips!

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• Advanced donut caching: using dynamically loaded controls

  - by DigiMortal

  Yesterday I solved one caching problem with local community portal. I enabled output cache on SharePoint Server 2007 to make site faster. Although caching works fine I needed to do some additional work because there are some controls that show different content to different users. In this example I will show you how to use “donut caching” with user controls – powerful way to drive some content around cache. About donut caching Donut caching means that although you are caching your content you have some holes in it so you can still affect the output that goes to user. By example you can cache front page on your site and still show welcome message that contains correct user name. To get better idea about donut caching I suggest you to read ScottGu posting Tip/Trick: Implement "Donut Caching" with the ASP.NET 2.0 Output Cache Substitution Feature. Basically donut caching uses ASP.NET substitution control. In output this control is replaced by string you return from static method bound to substitution control. Again, take a look at ScottGu blog posting I referred above. Problem If you look at Scott’s example it is pretty plain and easy by its output. All it does is it writes out current user name as string. Here are examples of my login area for anonymous and authenticated users:    It is clear that outputting mark-up for these views as string is pretty lame to implement in code at string level. Every little change in design will end up with new version of controls library because some parts of design “live” there. Solution: using user controls I worked out easy solution to my problem. I used cache substitution and user controls together. I have three user controls: LogInControl – this is the proxy control that checks which “real” control to load. AnonymousLogInControl – template and logic for anonymous users login area. AuthenticatedLogInControl – template and logic for authenticated users login area. This is the control we render for each user separately because it contains user name and user profile fill percent. Anonymous control is not very interesting because it is only about keeping mark-up in separate file. Interesting parts are LogInControl and AuthenticatedLogInControl. Creating proxy control The first thing was to create control that has substitution area where “real” control is loaded. This proxy control should also be available to decide which control to load. The definition of control is very primitive. <%@ Control EnableViewState="false" Inherits="MyPortal.Profiles.LogInControl" %> <asp:Substitution runat="server" MethodName="ShowLogInBox" /> But code is a little bit tricky. Based on current user instance we decide which login control to load. Then we create page instance and load our control through it. When control is loaded we will call DataBind() method. In this method we evaluate all fields in loaded control (it was best choice as Load and other events will not be fired). Take a look at the code. public static string ShowLogInBox(HttpContext context) {     var user = SPContext.Current.Web.CurrentUser;     string controlName;       if (user != null)         controlName = "AuthenticatedLogInControl.ascx";     else         controlName = "AnonymousLogInControl.ascx";       var path = "~/_controltemplates/" + controlName;     var output = new StringBuilder(10000);       using(var page = new Page())     using(var ctl = page.LoadControl(path))     using(var writer = new StringWriter(output))     using(var htmlWriter = new HtmlTextWriter(writer))     {         ctl.DataBind();         ctl.RenderControl(htmlWriter);     }     return output.ToString(); } When control is bound to data we ask to render it its contents to StringBuilder. Now we have the output of control as string and we can return it from our method. Of course, notice how correct I am with resources disposing. :) The method that returns contents for substitution control is static method that has no connection with control instance because hen page is read from cache there are no instances of controls available. Conclusion As you saw it was not very hard to use donut caching with user controls. Instead of writing mark-up of controls to static method that is bound to substitution control we can still use our user controls.

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• XNA Notes 005

  - by George Clingerman

  Another week and another crazy amount of activity going on in the XNA community. I’m fairly certain I missed over half of it. In fact, if I am missing things, make sure to email me and I’ll try and make sure I catch it next week! ([email protected]). Also, if you’ve got any advice, things you like/don’t like about the way these XNA Notes are going let me know. I always appreciate feedback (currently spammers are leaving me the nicest comments so you guys have work to do!) Without further ado, here’s this week’s notes! Time Critical XNA News The XNA Team Blob reminds us that February 7th is the last day to submit XNA 3.1 games to peer review! http://blogs.msdn.com/b/xna/archive/2011/01/31/7-days-left-to-submit-xna-gs-3-1-games-on-app-hub.aspx XNA MVPS Chris Williams kicks off the marketing campaign for our book http://geekswithblogs.net/cwilliams/archive/2011/01/28/143680.aspx Catalin Zima posts the comparison cheat sheet for why Angry Birds is different than Chickens Can’t Fly http://www.amusedsloth.com/2011/02/comparison-cheat-sheet-for-chickens-cant-fly-and-angry-birds/ Jim Perry congratulates the developers selected by Game Developer Magazine for Best Xbox LIVE Indie Games of 2010 http://machxgames.com/blog/?p=24 @NemoKrad posts his XNAKUUG talks for all to enjoy http://twitter.com/NemoKrad/statuses/33142362502864896 http://xna-uk.net/blogs/randomchaos/archive/2011/02/03/xblig-uk-2011-january-amp-february-talk.aspx George  (that’s me!) preps for his XNA talk coming up on the 8th http://twitter.com/clingermangw/statuses/32669550554124288 http://www.portlandsilverlight.net/Meetings/Details/15 XNA Developers FireFly posts the last tutorial in his XNA Tower Defense tutorial series http://forums.create.msdn.com/forums/p/26442/451460.aspx#451460 http://xnatd.blogspot.com/2011/01/tutorial-14-polishing-game.html @fredericmy posts the main difference when porting a game from Windows Phone 7 to Xbox 360 http://fairyengine.blogspot.com/2011/01/main-differences-when-porting-game-from.html @ElementCy creates a pretty rad video of a MineCraft type terrain created using XNA http://www.youtube.com/watch?v=Waw1f7wnl9I Andrew Russel gets the first XNA badge on gamedev.stackexchange http://twitter.com/_AndrewRussell/statuses/32322877004972032 http://gamedev.stackexchange.com/badges?tab=tags And his funding for ExEn has passed $7000 only $3000 to go http://twitter.com/_AndrewRussell/statuses/33042412804771840 Subodh Pushpak blogs about his Windows Phone 7 XNA talk http://geekswithblogs.net/subodhnpushpak/archive/2011/02/01/windows-phone-7-silverlight--xna-development-talk.aspx Slyprid releases the latest version of Transmute and needs more people to test http://twitter.com/slyprid/statuses/32452488418299904 http://forgottenstarstudios.com/ SpynDoctorGames celebrates the 1 year anniversary of Your Doodles Are Bugged! Congrats! http://twitter.com/SpynDoctorGames/statuses/32511689068908544 Noogy (creator of Dust the Elysian Tail) prepares his conversion to XNA 4.0 http://twitter.com/NoogyTweet/statuses/32522008449253376 @philippedasilva posts about the Indiefreaks Game Framework v0.2.0.0 Input management system http://twitter.com/philippedasilva/statuses/32763393957957632 http://indiefreaks.com/2011/02/02/behind-smart-input-system-feature/ Mommy’s Best Games debates what to do about High Scores with their new update http://mommysbest.blogspot.com/2011/02/high-score-shake-up.html @BinaryTweedDeej want to know if there’s anything the community needs to make XNA games for the PC. Give him some feedback! http://twitter.com/BinaryTweedDeej/status/32895453863354368 @mikebmcl promises to write us all a book (I can’t wait to read it!) http://twitter.com/mikebmcl/statuses/33206499102687233 @werezompire is going to live, LIVE, thanks to all the generosity and support from the community! http://twitter.com/werezompire/statuses/32840147644977153 Xbox LIVE Indie Games (XBLIG) Making money in Xbox 360 indie game development. Is it possible? http://www.bitmob.com/articles/making-money-in-xbox-360-indie-game-development-is-it-possible @AlejandroDaJ posts some thoughts abut the bitmob article http://twitter.com/AlejandroDaJ/statuses/31068552165330944 http://www.apathyworks.com/blog/view.php?id=00215 Kobun gets my respect as an XBLIG champion. I’m not sure who Kobun is, but if you’ve every read through the comment sections any time Kotaku writes about XBLIGs you’ll see a lot of confusion, disinformation in there. Kobun has been waging a secret war battling that lack of knowledge and he does it well. Also he’s running a pretty kick ass site for Xbox LIVE Indie Game reviews http://xboxindies.teamkobun.com/ @radiangames releases his last Xbox LIVE Indie Game...for now http://bit.ly/gMK6lE Playing Avaglide with the Kinect controller http://www.youtube.com/watch?v=UqAYbHww53o http://www.joystiq.com/2011/01/30/kinect-hacks-take-to-the-skies-with-avaglide/ Luke Schneider of Radiangames interviewed in Edge magazine http://www.next-gen.biz/features/radiangames-venture Digital Quarters posts thoughts on why XBLIG’s online requirement kills certain genres http://digitalquarters.blogspot.com/2011/02/thoughts-why-xbligs-online-requirement.html Mommy’s Best Games shares the news that several XBLIGs were featured in the March 2011 issue of Famitsu 360 http://forums.create.msdn.com/forums/p/33455/451487.aspx#451487 NaviFairy continues with his Indie-Game-A-Day http://gaygamer.net/2011/02/indie_game_a_day_epic_dungeon.html http://gaygamer.net/2011/02/indie_game_a_day_break_limit_r.html and more every day...that’s kind of the point! Keep your eye on this series! VVGTV continues with it’s awesome reviews/promotions for XBLIGs http://vvgtv.com/ http://vvgtv.com/2011/02/03/iredia-atrams-secret-xblig-review-2/ http://vvgtv.com/2011/02/02/poopocalypse-coming-soon-to-xblig/ ….and even more, you get the point. Magicka is an Indie Game doing really well on Steam AND it’s made using XNA http://www.magickagame.com/ http://twitter.com/Magickagame/statuses/32712762580799488 GameMarx reviews Antipole http://www.gamemarx.com/reviews/73/antipole-is-vvvvvvery-good.aspx Armless Octopus review Alpha Squad http://www.armlessoctopus.com/2011/01/28/xbox-indie-review-alpha-squad/ An interesting article about Kodu that Jim Perry found http://twitter.com/MachXGames/statuses/32848044105924608 http://www.develop-online.net/news/36915/10-year-old-Jordan-makes-games-The-UK-needs-more-like-her XNA Game Development Sgt. Conker posts about the Natur beta, a new book and whether you can make money with XBLIG http://www.sgtconker.com/ http://www.sgtconker.com/2011/01/a-new-book-on-the-block-and-a-new-natur-beta/ http://www.sgtconker.com/2011/01/making-money-in-xbox-360-indie-game-development-is-it-possible/ Tips for setting up SVN http://bit.ly/fKxgFh @bsimser found tons of royalty free music and soundfx for your XNA Games http://twitter.com/bsimser/statuses/31426632933711872 Post on the new features in the next Sunburn Editor http://www.synapsegaming.com/blogs/fivesidedbarrel/archive/2011/01/28/new-editor-features-prefabs-components-and-more.aspx @jasons_novaleaf posts source code for light pre-pass optimizations for #xna http://twitter.com/jasons_novaleaf/statuses/33348855403642880 http://jcoluna.wordpress.com/2011/02/01/xna-4-0-light-pre-pass-optimization-round-one/ I’ve been learning about doing an A.I. for turn based games and this article was a great resource. http://www.gamasutra.com/view/feature/1535/designing_ai_algorithms_for_.php?print=1

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• Auto DOP and Concurrency

  - by jean-pierre.dijcks

  After spending some time in the cloud, I figured it is time to come down to earth and start discussing some of the new Auto DOP features some more. As Database Machines (the v2 machine runs Oracle Database 11.2) are effectively selling like hotcakes, it makes some sense to talk about the new parallel features in more detail. For basic understanding make sure you have read the initial post. The focus there is on Auto DOP and queuing, which is to some extend the focus here. But now I want to discuss the concurrency a little and explain some of the relevant parameters and their impact, specifically in a situation with concurrency on the system. The goal of Auto DOP The idea behind calculating the Automatic Degree of Parallelism is to find the highest possible DOP (ideal DOP) that still scales. In other words, if we were to increase the DOP even more  above a certain DOP we would see a tailing off of the performance curve and the resource cost / performance would become less optimal. Therefore the ideal DOP is the best resource/performance point for that statement. The goal of Queuing On a normal production system we should see statements running concurrently. On a Database Machine we typically see high concurrency rates, so we need to find a way to deal with both high DOP’s and high concurrency. Queuing is intended to make sure we Don’t throttle down a DOP because other statements are running on the system Stay within the physical limits of a system’s processing power Instead of making statements go at a lower DOP we queue them to make sure they will get all the resources they want to run efficiently without trashing the system. The theory – and hopefully – practice is that by giving a statement the optimal DOP the sum of all statements runs faster with queuing than without queuing. Increasing the Number of Potential Parallel Statements To determine how many statements we will consider running in parallel a single parameter should be looked at. That parameter is called PARALLEL_MIN_TIME_THRESHOLD. The default value is set to 10 seconds. So far there is nothing new here…, but do realize that anything serial (e.g. that stays under the threshold) goes straight into processing as is not considered in the rest of this post. Now, if you have a system where you have two groups of queries, serial short running and potentially parallel long running ones, you may want to worry only about the long running ones with this parallel statement threshold. As an example, lets assume the short running stuff runs on average between 1 and 15 seconds in serial (and the business is quite happy with that). The long running stuff is in the realm of 1 – 5 minutes. It might be a good choice to set the threshold to somewhere north of 30 seconds. That way the short running queries all run serial as they do today (if it ain’t broken, don’t fix it) and allows the long running ones to be evaluated for (higher degrees of) parallelism. This makes sense because the longer running ones are (at least in theory) more interesting to unleash a parallel processing model on and the benefits of running these in parallel are much more significant (again, that is mostly the case). Setting a Maximum DOP for a Statement Now that you know how to control how many of your statements are considered to run in parallel, lets talk about the specific degree of any given statement that will be evaluated. As the initial post describes this is controlled by PARALLEL_DEGREE_LIMIT. This parameter controls the degree on the entire cluster and by default it is CPU (meaning it equals Default DOP). For the sake of an example, let’s say our Default DOP is 32. Looking at our 5 minute queries from the previous paragraph, the limit to 32 means that none of the statements that are evaluated for Auto DOP ever runs at more than DOP of 32. Concurrently Running a High DOP A basic assumption about running high DOP statements at high concurrency is that you at some point in time (and this is true on any parallel processing platform!) will run into a resource limitation. And yes, you can then buy more hardware (e.g. expand the Database Machine in Oracle’s case), but that is not the point of this post… The goal is to find a balance between the highest possible DOP for each statement and the number of statements running concurrently, but with an emphasis on running each statement at that highest efficiency DOP. The PARALLEL_SERVER_TARGET parameter is the all important concurrency slider here. Setting this parameter to a higher number means more statements get to run at their maximum parallel degree before queuing kicks in.  PARALLEL_SERVER_TARGET is set per instance (so needs to be set to the same value on all 8 nodes in a full rack Database Machine). Just as a side note, this parameter is set in processes, not in DOP, which equates to 4* Default DOP (2 processes for a DOP, default value is 2 * Default DOP, hence a default of 4 * Default DOP). Let’s say we have PARALLEL_SERVER_TARGET set to 128. With our limit set to 32 (the default) we are able to run 4 statements concurrently at the highest DOP possible on this system before we start queuing. If these 4 statements are running, any next statement will be queued. To run a system at high concurrency the PARALLEL_SERVER_TARGET should be raised from its default to be much closer (start with 60% or so) to PARALLEL_MAX_SERVERS. By using both PARALLEL_SERVER_TARGET and PARALLEL_DEGREE_LIMIT you can control easily how many statements run concurrently at good DOPs without excessive queuing. Because each workload is a little different, it makes sense to plan ahead and look at these parameters and set these based on your requirements.

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• CLR via C# 3rd Edition is out

  - by Abhijeet Patel

  Time for some book news update. CLR via C#, 3rd Edition seems to have been out for a little while now. The book was released in early Feb this year, and needless to say my copy is on it’s way. I can barely wait to dig in and chew on the goodies that one of the best technical authors and software professionals I respect has in store. The 2nd edition of the book was an absolute treat and this edition promises to be no less. Here is a brief description of what’s new and updated from the 2nd edition. Part I – CLR Basics Chapter 1-The CLR’s Execution Model Added about discussion about C#’s /optimize and /debug switches and how they relate to each other. Chapter 2-Building, Packaging, Deploying, and Administering Applications and Types Improved discussion about Win32 manifest information and version resource information. Chapter 3-Shared Assemblies and Strongly Named Assemblies Added discussion of TypeForwardedToAttribute and TypeForwardedFromAttribute. Part II – Designing Types Chapter 4-Type Fundamentals No new topics. Chapter 5-Primitive, Reference, and Value Types Enhanced discussion of checked and unchecked code and added discussion of new BigInteger type. Also added discussion of C# 4.0’s dynamic primitive type. Chapter 6-Type and Member Basics No new topics. Chapter 7-Constants and Fields No new topics. Chapter 8-Methods Added discussion of extension methods and partial methods. Chapter 9-Parameters Added discussion of optional/named parameters and implicitly-typed local variables. Chapter 10-Properties Added discussion of automatically-implemented properties, properties and the Visual Studio debugger, object and collection initializers, anonymous types, the System.Tuple type and the ExpandoObject type. Chapter 11-Events Added discussion of events and thread-safety as well as showing a cool extension method to simplify the raising of an event. Chapter 12-Generics Added discussion of delegate and interface generic type argument variance. Chapter 13-Interfaces No new topics. Part III – Essential Types Chapter 14-Chars, Strings, and Working with Text No new topics. Chapter 15-Enums Added coverage of new Enum and Type methods to access enumerated type instances. Chapter 16-Arrays Added new section on initializing array elements. Chapter 17-Delegates Added discussion of using generic delegates to avoid defining new delegate types. Also added discussion of lambda expressions. Chapter 18-Attributes No new topics. Chapter 19-Nullable Value Types Added discussion on performance. Part IV – CLR Facilities Chapter 20-Exception Handling and State Management This chapter has been completely rewritten. It is now about exception handling and state management. It includes discussions of code contracts and constrained execution regions (CERs). It also includes a new section on trade-offs between writing productive code and reliable code. Chapter 21-Automatic Memory Management Added discussion of C#’s fixed state and how it works to pin objects in the heap. Rewrote the code for weak delegates so you can use them with any class that exposes an event (the class doesn’t have to support weak delegates itself). Added discussion on the new ConditionalWeakTable class, GC Collection modes, Full GC notifications, garbage collection modes and latency modes. I also include a new sample showing how your application can receive notifications whenever Generation 0 or 2 collections occur. Chapter 22-CLR Hosting and AppDomains Added discussion of side-by-side support allowing multiple CLRs to be loaded in a single process. Added section on the performance of using MarshalByRefObject-derived types. Substantially rewrote the section on cross-AppDomain communication. Added section on AppDomain Monitoring and first chance exception notifications. Updated the section on the AppDomainManager class. Chapter 23-Assembly Loading and Reflection Added section on how to deploy a single file with dependent assemblies embedded inside it. Added section comparing reflection invoke vs bind/invoke vs bind/create delegate/invoke vs C#’s dynamic type. Chapter 24-Runtime Serialization This is a whole new chapter that was not in the 2nd Edition. Part V – Threading Chapter 25-Threading Basics Whole new chapter motivating why Windows supports threads, thread overhead, CPU trends, NUMA Architectures, the relationship between CLR threads and Windows threads, the Thread class, reasons to use threads, thread scheduling and priorities, foreground thread vs background threads. Chapter 26-Performing Compute-Bound Asynchronous Operations Whole new chapter explaining the CLR’s thread pool. This chapter covers all the new .NET 4.0 constructs including cooperative cancelation, Tasks, the aralle class, parallel language integrated query, timers, how the thread pool manages its threads, cache lines and false sharing. Chapter 27-Performing I/O-Bound Asynchronous Operations Whole new chapter explaining how Windows performs synchronous and asynchronous I/O operations. Then, I go into the CLR’s Asynchronous Programming Model, my AsyncEnumerator class, the APM and exceptions, Applications and their threading models, implementing a service asynchronously, the APM and Compute-bound operations, APM considerations, I/O request priorities, converting the APM to a Task, the event-based Asynchronous Pattern, programming model soup. Chapter 28-Primitive Thread Synchronization Constructs Whole new chapter discusses class libraries and thread safety, primitive user-mode, kernel-mode constructs, and data alignment. Chapter 29-Hybrid Thread Synchronization Constructs Whole new chapter discussion various hybrid constructs such as ManualResetEventSlim, SemaphoreSlim, CountdownEvent, Barrier, ReaderWriterLock(Slim), OneManyResourceLock, Monitor, 3 ways to solve the double-check locking technique, .NET 4.0’s Lazy and LazyInitializer classes, the condition variable pattern, .NET 4.0’s concurrent collection classes, the ReaderWriterGate and SyncGate classes.

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• Atmospheric Scattering

  - by Lawrence Kok

  I'm trying to implement atmospheric scattering based on Sean O`Neil algorithm that was published in GPU Gems 2. But I have some trouble getting the shader to work. My latest attempts resulted in: http://img253.imageshack.us/g/scattering01.png/ I've downloaded sample code of O`Neil from: http://http.download.nvidia.com/developer/GPU_Gems_2/CD/Index.html. Made minor adjustments to the shader 'SkyFromAtmosphere' that would allow it to run in AMD RenderMonkey. In the images it is see-able a form of banding occurs, getting an blueish tone. However it is only applied to one half of the sphere, the other half is completely black. Also the banding appears to occur at Zenith instead of Horizon, and for a reason I managed to get pac-man shape. I would appreciate it if somebody could show me what I'm doing wrong. Vertex Shader: uniform mat4 matView; uniform vec4 view_position; uniform vec3 v3LightPos; const int nSamples = 3; const float fSamples = 3.0; const vec3 Wavelength = vec3(0.650,0.570,0.475); const vec3 v3InvWavelength = 1.0f / vec3( Wavelength.x * Wavelength.x * Wavelength.x * Wavelength.x, Wavelength.y * Wavelength.y * Wavelength.y * Wavelength.y, Wavelength.z * Wavelength.z * Wavelength.z * Wavelength.z); const float fInnerRadius = 10; const float fOuterRadius = fInnerRadius * 1.025; const float fInnerRadius2 = fInnerRadius * fInnerRadius; const float fOuterRadius2 = fOuterRadius * fOuterRadius; const float fScale = 1.0 / (fOuterRadius - fInnerRadius); const float fScaleDepth = 0.25; const float fScaleOverScaleDepth = fScale / fScaleDepth; const vec3 v3CameraPos = vec3(0.0, fInnerRadius * 1.015, 0.0); const float fCameraHeight = length(v3CameraPos); const float fCameraHeight2 = fCameraHeight * fCameraHeight; const float fm_ESun = 150.0; const float fm_Kr = 0.0025; const float fm_Km = 0.0010; const float fKrESun = fm_Kr * fm_ESun; const float fKmESun = fm_Km * fm_ESun; const float fKr4PI = fm_Kr * 4 * 3.141592653; const float fKm4PI = fm_Km * 4 * 3.141592653; varying vec3 v3Direction; varying vec4 c0, c1; float scale(float fCos) { float x = 1.0 - fCos; return fScaleDepth * exp(-0.00287 + x*(0.459 + x*(3.83 + x*(-6.80 + x*5.25)))); } void main( void ) { // Get the ray from the camera to the vertex, and its length (which is the far point of the ray passing through the atmosphere) vec3 v3FrontColor = vec3(0.0, 0.0, 0.0); vec3 v3Pos = normalize(gl_Vertex.xyz) * fOuterRadius; vec3 v3Ray = v3CameraPos - v3Pos; float fFar = length(v3Ray); v3Ray = normalize(v3Ray); // Calculate the ray's starting position, then calculate its scattering offset vec3 v3Start = v3CameraPos; float fHeight = length(v3Start); float fDepth = exp(fScaleOverScaleDepth * (fInnerRadius - fCameraHeight)); float fStartAngle = dot(v3Ray, v3Start) / fHeight; float fStartOffset = fDepth*scale(fStartAngle); // Initialize the scattering loop variables float fSampleLength = fFar / fSamples; float fScaledLength = fSampleLength * fScale; vec3 v3SampleRay = v3Ray * fSampleLength; vec3 v3SamplePoint = v3Start + v3SampleRay * 0.5; // Now loop through the sample rays for(int i=0; i<nSamples; i++) { float fHeight = length(v3SamplePoint); float fDepth = exp(fScaleOverScaleDepth * (fInnerRadius - fHeight)); float fLightAngle = dot(normalize(v3LightPos), v3SamplePoint) / fHeight; float fCameraAngle = dot(normalize(v3Ray), v3SamplePoint) / fHeight; float fScatter = (-fStartOffset + fDepth*( scale(fLightAngle) - scale(fCameraAngle)))/* 0.25f*/; vec3 v3Attenuate = exp(-fScatter * (v3InvWavelength * fKr4PI + fKm4PI)); v3FrontColor += v3Attenuate * (fDepth * fScaledLength); v3SamplePoint += v3SampleRay; } // Finally, scale the Mie and Rayleigh colors and set up the varying variables for the pixel shader vec4 newPos = vec4( (gl_Vertex.xyz + view_position.xyz), 1.0); gl_Position = gl_ModelViewProjectionMatrix * vec4(newPos.xyz, 1.0); gl_Position.z = gl_Position.w * 0.99999; c1 = vec4(v3FrontColor * fKmESun, 1.0); c0 = vec4(v3FrontColor * (v3InvWavelength * fKrESun), 1.0); v3Direction = v3CameraPos - v3Pos; } Fragment Shader: uniform vec3 v3LightPos; varying vec3 v3Direction; varying vec4 c0; varying vec4 c1; const float g =-0.90f; const float g2 = g * g; const float Exposure =2; void main(void){ float fCos = dot(normalize(v3LightPos), v3Direction) / length(v3Direction); float fMiePhase = 1.5 * ((1.0 - g2) / (2.0 + g2)) * (1.0 + fCos*fCos) / pow(1.0 + g2 - 2.0*g*fCos, 1.5); gl_FragColor = c0 + fMiePhase * c1; gl_FragColor.a = 1.0; }

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• Why lock-free data structures just aren't lock-free enough

  - by Alex.Davies

  Today's post will explore why the current ways to communicate between threads don't scale, and show you a possible way to build scalable parallel programming on top of shared memory. The problem with shared memory Soon, we will have dozens, hundreds and then millions of cores in our computers. It's inevitable, because individual cores just can't get much faster. At some point, that's going to mean that we have to rethink our architecture entirely, as millions of cores can't all access a shared memory space efficiently. But millions of cores are still a long way off, and in the meantime we'll see machines with dozens of cores, struggling with shared memory. Alex's tip: The best way for an application to make use of that increasing parallel power is to use a concurrency model like actors, that deals with synchronisation issues for you. Then, the maintainer of the actors framework can find the most efficient way to coordinate access to shared memory to allow your actors to pass messages to each other efficiently. At the moment, NAct uses the .NET thread pool and a few locks to marshal messages. It works well on dual and quad core machines, but it won't scale to more cores. Every time we use a lock, our core performs an atomic memory operation (eg. CAS) on a cell of memory representing the lock, so it's sure that no other core can possibly have that lock. This is very fast when the lock isn't contended, but we need to notify all the other cores, in case they held the cell of memory in a cache. As the number of cores increases, the total cost of a lock increases linearly. A lot of work has been done on "lock-free" data structures, which avoid locks by using atomic memory operations directly. These give fairly dramatic performance improvements, particularly on systems with a few (2 to 4) cores. The .NET 4 concurrent collections in System.Collections.Concurrent are mostly lock-free. However, lock-free data structures still don't scale indefinitely, because any use of an atomic memory operation still involves every core in the system. A sync-free data structure Some concurrent data structures are possible to write in a completely synchronization-free way, without using any atomic memory operations. One useful example is a single producer, single consumer (SPSC) queue. It's easy to write a sync-free fixed size SPSC queue using a circular buffer*. Slightly trickier is a queue that grows as needed. You can use a linked list to represent the queue, but if you leave the nodes to be garbage collected once you're done with them, the GC will need to involve all the cores in collecting the finished nodes. Instead, I've implemented a proof of concept inspired by this intel article which reuses the nodes by putting them in a second queue to send back to the producer. * In all these cases, you need to use memory barriers correctly, but these are local to a core, so don't have the same scalability problems as atomic memory operations. Performance tests I tried benchmarking my SPSC queue against the .NET ConcurrentQueue, and against a standard Queue protected by locks. In some ways, this isn't a fair comparison, because both of these support multiple producers and multiple consumers, but I'll come to that later. I started on my dual-core laptop, running a simple test that had one thread producing 64 bit integers, and another consuming them, to measure the pure overhead of the queue. So, nothing very interesting here. Both concurrent collections perform better than the lock-based one as expected, but there's not a lot to choose between the ConcurrentQueue and my SPSC queue. I was a little disappointed, but then, the .NET Framework team spent a lot longer optimising it than I did. So I dug out a more powerful machine that Red Gate's DBA tools team had been using for testing. It is a 6 core Intel i7 machine with hyperthreading, adding up to 12 logical cores. Now the results get more interesting. As I increased the number of producer-consumer pairs to 6 (to saturate all 12 logical cores), the locking approach was slow, and got even slower, as you'd expect. What I didn't expect to be so clear was the drop-off in performance of the lock-free ConcurrentQueue. I could see the machine only using about 20% of available CPU cycles when it should have been saturated. My interpretation is that as all the cores used atomic memory operations to safely access the queue, they ended up spending most of the time notifying each other about cache lines that need invalidating. The sync-free approach scaled perfectly, despite still working via shared memory, which after all, should still be a bottleneck. I can't quite believe that the results are so clear, so if you can think of any other effects that might cause them, please comment! Obviously, this benchmark isn't realistic because we're only measuring the overhead of the queue. Any real workload, even on a machine with 12 cores, would dwarf the overhead, and there'd be no point worrying about this effect. But would that be true on a machine with 100 cores? Still to be solved. The trouble is, you can't build many concurrent algorithms using only an SPSC queue to communicate. In particular, I can't see a way to build something as general purpose as actors on top of just SPSC queues. Fundamentally, an actor needs to be able to receive messages from multiple other actors, which seems to need an MPSC queue. I've been thinking about ways to build a sync-free MPSC queue out of multiple SPSC queues and some kind of sign-up mechanism. Hopefully I'll have something to tell you about soon, but leave a comment if you have any ideas.

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• Find only physical network adapters with WMI Win32_NetworkAdapter class

  - by Mladen Prajdic

  WMI is Windows Management Instrumentation infrastructure for managing data and machines. We can access it by using WQL (WMI querying language or SQL for WMI). One thing to remember from the WQL link is that it doesn't support ORDER BY. This means that when you do SELECT * FROM wmiObject, the returned order of the objects is not guaranteed. It can return adapters in different order based on logged-in user, permissions of that user, etc… This is not documented anywhere that I've looked and is derived just from my observations. To get network adapters we have to query the Win32_NetworkAdapter class. This returns us all network adapters that windows detect, real and virtual ones, however it only supplies IPv4 data. I've tried various methods of combining properties that are common on all systems since Windows XP. The first thing to do to remove all virtual adapters (like tunneling, WAN miniports, etc…) created by Microsoft. We do this by adding WHERE Manufacturer!='Microsoft' to our WMI query. This greatly narrows the number of adapters we have to work with. Just on my machine it went from 20 adapters to 5. What was left were one real physical Realtek LAN adapter, 2 virtual adapters installed by VMware and 2 virtual adapters installed by VirtualBox. If you read the Win32_NetworkAdapter help page you'd notice that there's an AdapterType that enumerates various adapter types like LAN or Wireless and AdapterTypeID that gives you the same information as AdapterType only in integer form. The dirty little secret is that these 2 properties don't work. They are both hardcoded, AdapterTypeID to "0" and AdapterType to "Ethernet 802.3". The only exceptions I've seen so far are adapters that have no values at all for the two properties, "RAS Async Adapter" that has values of AdapterType = "Wide Area Network" and AdapterTypeID = "3" and various tunneling adapters that have values of AdapterType = "Tunnel" and AdapterTypeID = "15". In the help docs there isn't even a value for 15. So this property was of no help. Next property to give hope is NetConnectionId. This is the name of the network connection as it appears in the Control Panel -> Network Connections. Problem is this value is also localized into various languages and can have different names for different connection. So both of these properties don't help and we haven't even started talking about eliminating virtual adapters. Same as the previous one this property was also of no help. Next two properties I checked were ConfigManagerErrorCode and NetConnectionStatus in hopes of finding disabled and disconnected adapters. If an adapter is enabled but disconnected the ConfigManagerErrorCode = 0 with different NetConnectionStatus. If the adapter is disabled it reports ConfigManagerErrorCode = 22. This looked like a win by using (ConfigManagerErrorCode=0 or ConfigManagerErrorCode=22) in our condition. This way we get enabled (connected and disconnected adapters). Problem with all of the above properties is that none of them filter out the virtual adapters installed by virtualization software like VMware and VirtualBox. The last property to give hope is PNPDeviceID. There's an interesting observation about physical and virtual adapters with this property. Every virtual adapter PNPDeviceID starts with "ROOT\". Even VMware and VirtualBox ones. There were some really, really old physical adapters that had PNPDeviceID starting with "ROOT\" but those were in pre win XP era AFAIK. Since my minimum system to check was Windows XP SP2 I didn't have to worry about those. The only virtual adapter I've seen to not have PNPDeviceID start with "ROOT\" is the RAS Async Adapter for Wide Area Network. But because it is made by Microsoft we've eliminated it with the first condition for the manufacturer. Using the PNPDeviceID has so far proven to be really effective and I've tested it on over 20 different computers of various configurations from Windows XP laptops with wireless and bluetooth cards to virtualized Windows 2008 R2 servers. So far it always worked as expected. I will appreciate you letting me know if you find a configuration where it doesn't work. Let's see some C# code how to do this: ManagementObjectSearcher mos = null;// WHERE Manufacturer!='Microsoft' removes all of the // Microsoft provided virtual adapters like tunneling, miniports, and Wide Area Network adapters.mos = new ManagementObjectSearcher(@"SELECT * FROM Win32_NetworkAdapter WHERE Manufacturer != 'Microsoft'");// Trying the ConfigManagerErrorCode and NetConnectionStatus variations // proved to still not be enough and it returns adapters installed by // the virtualization software like VMWare and VirtualBox// ConfigManagerErrorCode = 0 -> Device is working properly. This covers enabled and/or disconnected devices// ConfigManagerErrorCode = 22 AND NetConnectionStatus = 0 -> Device is disabled and Disconnected. // Some virtual devices report ConfigManagerErrorCode = 22 (disabled) and some other NetConnectionStatus than 0mos = new ManagementObjectSearcher(@"SELECT * FROM Win32_NetworkAdapter WHERE Manufacturer != 'Microsoft' AND (ConfigManagerErrorCode = 0 OR (ConfigManagerErrorCode = 22 AND NetConnectionStatus = 0))");// Final solution with filtering on the Manufacturer and PNPDeviceID not starting with "ROOT\"// Physical devices have PNPDeviceID starting with "PCI\" or something else besides "ROOT\"mos = new ManagementObjectSearcher(@"SELECT * FROM Win32_NetworkAdapter WHERE Manufacturer != 'Microsoft' AND NOT PNPDeviceID LIKE 'ROOT\\%'");// Get the physical adapters and sort them by their index. // This is needed because they're not sorted by defaultIList<ManagementObject> managementObjectList = mos.Get() .Cast<ManagementObject>() .OrderBy(p => Convert.ToUInt32(p.Properties["Index"].Value)) .ToList();// Let's just show all the properties for all physical adapters.foreach (ManagementObject mo in managementObjectList){ foreach (PropertyData pd in mo.Properties) Console.WriteLine(pd.Name + ": " + (pd.Value ?? "N/A"));}   That's it. Hope this helps you in some way.

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