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  • Representing a number in a byte array (java programming)

    - by Mark Roberts
    I'm trying to represent the port number 9876 (or 0x2694 in hex) in a two byte array: class foo { public static void main (String args[]) { byte[] sendData = new byte[1]; sendData[0] = 0x26; sendData[1] = 0x94; } } But I get a warning about possible loss of precision: foo.java:5: possible loss of precision found : int required: byte sendData[1] = 0x94; ^ 1 error How can I represent the number 9876 in a two byte array without losing precision?

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  • Should I use AJAX or get every data beforehand

    - by rix501
    I have a web app where I need to change a drop down list dynamically depending on another drop down list. I have two options: Get all the data beforehand with PHP and "manage" it later with Javascript. Or get the data the user wants through AJAX. The thing is, that the page loads with all the data by default and the user can later select a sub category to narrow the drop downs. Which of the two options are better (faster, less resource intensive)?

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  • How Can I Implement This Function?

    - by hoora
    I'm a beginner and I want to write Java code in eclipse. This program takes two LinkedLists of integers (for example, a and b) and makes a LinkedList (for example d) in which every element is the sum of elements from a and b. However, I can't add these two elements from a and b because they are Objects Example: a=[3,4,6,7,8] b=[4,3,7,5,3,2,1] ------ d=[7,7,13,12,11,2,1]

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  • Do the changes to cpumask using sched_setaffinity() take place immediately

    - by Sukanto
    I am writing a linux kernel module that needs to pin two threads on two different cpus. I am planning to use sched_setaffinity() after exporting it in the kernel. Is there any other exported function for the same ? Also, if I set only 1 CPU in the cpumask, will the thread be moved to that cpu with immediate effect ? If not, how do I enforce the same ? Will it help to call schedule() just after sched_setaffinity() ?

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  • Does Java not support multiple inheritance?

    - by user1720616
    Lets us take instances of two classes public abstract class Shapes { public abstract void draw(Graphics g); } public class Rectangle extends Shapes { public void draw(Graphics g) { //implementation of the method } } here the class Rectangle has extended class Shapes and implicitly it extends class Object.I know no other extension is possible but cant we call inheriting classes Shapes and Object multiple inheritance?(Since inheriting two classes is multiple inheritance from one perspective)

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  • else or return?

    - by Ram
    Which one out of following two is best wrt to performance and standard practice. How does .NET internally handles these two code snippets? Code1 If(result) { process1(); } else { process2(); } Or Code 2 If(result) { process1(); return; } process2();

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  • Hosting the Razor Engine for Templating in Non-Web Applications

    - by Rick Strahl
    Microsoft’s new Razor HTML Rendering Engine that is currently shipping with ASP.NET MVC previews can be used outside of ASP.NET. Razor is an alternative view engine that can be used instead of the ASP.NET Page engine that currently works with ASP.NET WebForms and MVC. It provides a simpler and more readable markup syntax and is much more light weight in terms of functionality than the full blown WebForms Page engine, focusing only on features that are more along the lines of a pure view engine (or classic ASP!) with focus on expression and code rendering rather than a complex control/object model. Like the Page engine though, the parser understands .NET code syntax which can be embedded into templates, and behind the scenes the engine compiles markup and script code into an executing piece of .NET code in an assembly. Although it ships as part of the ASP.NET MVC and WebMatrix the Razor Engine itself is not directly dependent on ASP.NET or IIS or HTTP in any way. And although there are some markup and rendering features that are optimized for HTML based output generation, Razor is essentially a free standing template engine. And what’s really nice is that unlike the ASP.NET Runtime, Razor is fairly easy to host inside of your own non-Web applications to provide templating functionality. Templating in non-Web Applications? Yes please! So why might you host a template engine in your non-Web application? Template rendering is useful in many places and I have a number of applications that make heavy use of it. One of my applications – West Wind Html Help Builder - exclusively uses template based rendering to merge user supplied help text content into customizable and executable HTML markup templates that provide HTML output for CHM style HTML Help. This is an older product and it’s not actually using .NET at the moment – and this is one reason I’m looking at Razor for script hosting at the moment. For a few .NET applications though I’ve actually used the ASP.NET Runtime hosting to provide templating and mail merge style functionality and while that works reasonably well it’s a very heavy handed approach. It’s very resource intensive and has potential issues with versioning in various different versions of .NET. The generic implementation I created in the article above requires a lot of fix up to mimic an HTTP request in a non-HTTP environment and there are a lot of little things that have to happen to ensure that the ASP.NET runtime works properly most of it having nothing to do with the templating aspect but just satisfying ASP.NET’s requirements. The Razor Engine on the other hand is fairly light weight and completely decoupled from the ASP.NET runtime and the HTTP processing. Rather it’s a pure template engine whose sole purpose is to render text templates. Hosting this engine in your own applications can be accomplished with a reasonable amount of code (actually just a few lines with the tools I’m about to describe) and without having to fake HTTP requests. It’s also much lighter on resource usage and you can easily attach custom properties to your base template implementation to easily pass context from the parent application into templates all of which was rather complicated with ASP.NET runtime hosting. Installing the Razor Template Engine You can get Razor as part of the MVC 3 (RC and later) or Web Matrix. Both are available as downloadable components from the Web Platform Installer Version 3.0 (!important – V2 doesn’t show these components). If you already have that version of the WPI installed just fire it up. You can get the latest version of the Web Platform Installer from here: http://www.microsoft.com/web/gallery/install.aspx Once the platform Installer 3.0 is installed install either MVC 3 or ASP.NET Web Pages. Once installed you’ll find a System.Web.Razor assembly in C:\Program Files\Microsoft ASP.NET\ASP.NET Web Pages\v1.0\Assemblies\System.Web.Razor.dll which you can add as a reference to your project. Creating a Wrapper The basic Razor Hosting API is pretty simple and you can host Razor with a (large-ish) handful of lines of code. I’ll show the basics of it later in this article. However, if you want to customize the rendering and handle assembly and namespace includes for the markup as well as deal with text and file inputs as well as forcing Razor to run in a separate AppDomain so you can unload the code-generated assemblies and deal with assembly caching for re-used templates little more work is required to create something that is more easily reusable. For this reason I created a Razor Hosting wrapper project that combines a bunch of this functionality into an easy to use hosting class, a hosting factory that can load the engine in a separate AppDomain and a couple of hosting containers that provided folder based and string based caching for templates for an easily embeddable and reusable engine with easy to use syntax. If you just want the code and play with the samples and source go grab the latest code from the Subversion Repository at: http://www.west-wind.com:8080/svn/articles/trunk/RazorHosting/ or a snapshot from: http://www.west-wind.com/files/tools/RazorHosting.zip Getting Started Before I get into how hosting with Razor works, let’s take a look at how you can get up and running quickly with the wrapper classes provided. It only takes a few lines of code. The easiest way to use these Razor Hosting Wrappers is to use one of the two HostContainers provided. One is for hosting Razor scripts in a directory and rendering them as relative paths from these script files on disk. The other HostContainer serves razor scripts from string templates… Let’s start with a very simple template that displays some simple expressions, some code blocks and demonstrates rendering some data from contextual data that you pass to the template in the form of a ‘context’. Here’s a simple Razor template: @using System.Reflection Hello @Context.FirstName! Your entry was entered on: @Context.Entered @{ // Code block: Update the host Windows Form passed in through the context Context.WinForm.Text = "Hello World from Razor at " + DateTime.Now.ToString(); } AppDomain Id: @AppDomain.CurrentDomain.FriendlyName Assembly: @Assembly.GetExecutingAssembly().FullName Code based output: @{ // Write output with Response object from code string output = string.Empty; for (int i = 0; i < 10; i++) { output += i.ToString() + " "; } Response.Write(output); } Pretty easy to see what’s going on here. The only unusual thing in this code is the Context object which is an arbitrary object I’m passing from the host to the template by way of the template base class. I’m also displaying the current AppDomain and the executing Assembly name so you can see how compiling and running a template actually loads up new assemblies. Also note that as part of my context I’m passing a reference to the current Windows Form down to the template and changing the title from within the script. It’s a silly example, but it demonstrates two-way communication between host and template and back which can be very powerful. The easiest way to quickly render this template is to use the RazorEngine<TTemplateBase> class. The generic parameter specifies a template base class type that is used by Razor internally to generate the class it generates from a template. The default implementation provided in my RazorHosting wrapper is RazorTemplateBase. Here’s a simple one that renders from a string and outputs a string: var engine = new RazorEngine<RazorTemplateBase>(); // we can pass any object as context - here create a custom context var context = new CustomContext() { WinForm = this, FirstName = "Rick", Entered = DateTime.Now.AddDays(-10) }; string output = engine.RenderTemplate(this.txtSource.Text new string[] { "System.Windows.Forms.dll" }, context); if (output == null) this.txtResult.Text = "*** ERROR:\r\n" + engine.ErrorMessage; else this.txtResult.Text = output; Simple enough. This code renders a template from a string input and returns a result back as a string. It  creates a custom context and passes that to the template which can then access the Context’s properties. Note that anything passed as ‘context’ must be serializable (or MarshalByRefObject) – otherwise you get an exception when passing the reference over AppDomain boundaries (discussed later). Passing a context is optional, but is a key feature in being able to share data between the host application and the template. Note that we use the Context object to access FirstName, Entered and even the host Windows Form object which is used in the template to change the Window caption from within the script! In the code above all the work happens in the RenderTemplate method which provide a variety of overloads to read and write to and from strings, files and TextReaders/Writers. Here’s another example that renders from a file input using a TextReader: using (reader = new StreamReader("templates\\simple.csHtml", true)) { result = host.RenderTemplate(reader, new string[] { "System.Windows.Forms.dll" }, this.CustomContext); } RenderTemplate() is fairly high level and it handles loading of the runtime, compiling into an assembly and rendering of the template. If you want more control you can use the lower level methods to control each step of the way which is important for the HostContainers I’ll discuss later. Basically for those scenarios you want to separate out loading of the engine, compiling into an assembly and then rendering the template from the assembly. Why? So we can keep assemblies cached. In the code above a new assembly is created for each template rendered which is inefficient and uses up resources. Depending on the size of your templates and how often you fire them you can chew through memory very quickly. This slighter lower level approach is only a couple of extra steps: // we can pass any object as context - here create a custom context var context = new CustomContext() { WinForm = this, FirstName = "Rick", Entered = DateTime.Now.AddDays(-10) }; var engine = new RazorEngine<RazorTemplateBase>(); string assId = null; using (StringReader reader = new StringReader(this.txtSource.Text)) { assId = engine.ParseAndCompileTemplate(new string[] { "System.Windows.Forms.dll" }, reader); } string output = engine.RenderTemplateFromAssembly(assId, context); if (output == null) this.txtResult.Text = "*** ERROR:\r\n" + engine.ErrorMessage; else this.txtResult.Text = output; The difference here is that you can capture the assembly – or rather an Id to it – and potentially hold on to it to render again later assuming the template hasn’t changed. The HostContainers take advantage of this feature to cache the assemblies based on certain criteria like a filename and file time step or a string hash that if not change indicate that an assembly can be reused. Note that ParseAndCompileTemplate returns an assembly Id rather than the assembly itself. This is done so that that the assembly always stays in the host’s AppDomain and is not passed across AppDomain boundaries which would cause load failures. We’ll talk more about this in a minute but for now just realize that assemblies references are stored in a list and are accessible by this ID to allow locating and re-executing of the assembly based on that id. Reuse of the assembly avoids recompilation overhead and creation of yet another assembly that loads into the current AppDomain. You can play around with several different versions of the above code in the main sample form:   Using Hosting Containers for more Control and Caching The above examples simply render templates into assemblies each and every time they are executed. While this works and is even reasonably fast, it’s not terribly efficient. If you render templates more than once it would be nice if you could cache the generated assemblies for example to avoid re-compiling and creating of a new assembly each time. Additionally it would be nice to load template assemblies into a separate AppDomain optionally to be able to be able to unload assembli es and also to protect your host application from scripting attacks with malicious template code. Hosting containers provide also provide a wrapper around the RazorEngine<T> instance, a factory (which allows creation in separate AppDomains) and an easy way to start and stop the container ‘runtime’. The Razor Hosting samples provide two hosting containers: RazorFolderHostContainer and StringHostContainer. The folder host provides a simple runtime environment for a folder structure similar in the way that the ASP.NET runtime handles a virtual directory as it’s ‘application' root. Templates are loaded from disk in relative paths and the resulting assemblies are cached unless the template on disk is changed. The string host also caches templates based on string hashes – if the same string is passed a second time a cached version of the assembly is used. Here’s how HostContainers work. I’ll use the FolderHostContainer because it’s likely the most common way you’d use templates – from disk based templates that can be easily edited and maintained on disk. The first step is to create an instance of it and keep it around somewhere (in the example it’s attached as a property to the Form): RazorFolderHostContainer Host = new RazorFolderHostContainer(); public RazorFolderHostForm() { InitializeComponent(); // The base path for templates - templates are rendered with relative paths // based on this path. Host.TemplatePath = Path.Combine(Environment.CurrentDirectory, TemplateBaseFolder); // Add any assemblies you want reference in your templates Host.ReferencedAssemblies.Add("System.Windows.Forms.dll"); // Start up the host container Host.Start(); } Next anytime you want to render a template you can use simple code like this: private void RenderTemplate(string fileName) { // Pass the template path via the Context var relativePath = Utilities.GetRelativePath(fileName, Host.TemplatePath); if (!Host.RenderTemplate(relativePath, this.Context, Host.RenderingOutputFile)) { MessageBox.Show("Error: " + Host.ErrorMessage); return; } this.webBrowser1.Navigate("file://" + Host.RenderingOutputFile); } You can also render the output to a string instead of to a file: string result = Host.RenderTemplateToString(relativePath,context); Finally if you want to release the engine and shut down the hosting AppDomain you can simply do: Host.Stop(); Stopping the AppDomain and restarting it (ie. calling Stop(); followed by Start()) is also a nice way to release all resources in the AppDomain. The FolderBased domain also supports partial Rendering based on root path based relative paths with the same caching characteristics as the main templates. From within a template you can call out to a partial like this: @RenderPartial(@"partials\PartialRendering.cshtml", Context) where partials\PartialRendering.cshtml is a relative to the template root folder. The folder host example lets you load up templates from disk and display the result in a Web Browser control which demonstrates using Razor HTML output from templates that contain HTML syntax which happens to me my target scenario for Html Help Builder.   The Razor Engine Wrapper Project The project I created to wrap Razor hosting has a fair bit of code and a number of classes associated with it. Most of the components are internally used and as you can see using the final RazorEngine<T> and HostContainer classes is pretty easy. The classes are extensible and I suspect developers will want to build more customized host containers for their applications. Host containers are the key to wrapping up all functionality – Engine, BaseTemplate, AppDomain Hosting, Caching etc in a logical piece that is ready to be plugged into an application. When looking at the code there are a couple of core features provided: Core Razor Engine Hosting This is the core Razor hosting which provides the basics of loading a template, compiling it into an assembly and executing it. This is fairly straightforward, but without a host container that can cache assemblies based on some criteria templates are recompiled and re-created each time which is inefficient (although pretty fast). The base engine wrapper implementation also supports hosting the Razor runtime in a separate AppDomain for security and the ability to unload it on demand. Host Containers The engine hosting itself doesn’t provide any sort of ‘runtime’ service like picking up files from disk, caching assemblies and so forth. So my implementation provides two HostContainers: RazorFolderHostContainer and RazorStringHostContainer. The FolderHost works off a base directory and loads templates based on relative paths (sort of like the ASP.NET runtime does off a virtual). The HostContainers also deal with caching of template assemblies – for the folder host the file date is tracked and checked for updates and unless the template is changed a cached assembly is reused. The StringHostContainer similiarily checks string hashes to figure out whether a particular string template was previously compiled and executed. The HostContainers also act as a simple startup environment and a single reference to easily store and reuse in an application. TemplateBase Classes The template base classes are the base classes that from which the Razor engine generates .NET code. A template is parsed into a class with an Execute() method and the class is based on this template type you can specify. RazorEngine<TBaseTemplate> can receive this type and the HostContainers default to specific templates in their base implementations. Template classes are customizable to allow you to create templates that provide application specific features and interaction from the template to your host application. How does the RazorEngine wrapper work? You can browse the source code in the links above or in the repository or download the source, but I’ll highlight some key features here. Here’s part of the RazorEngine implementation that can be used to host the runtime and that demonstrates the key code required to host the Razor runtime. The RazorEngine class is implemented as a generic class to reflect the Template base class type: public class RazorEngine<TBaseTemplateType> : MarshalByRefObject where TBaseTemplateType : RazorTemplateBase The generic type is used to internally provide easier access to the template type and assignments on it as part of the template processing. The class also inherits MarshalByRefObject to allow execution over AppDomain boundaries – something that all the classes discussed here need to do since there is much interaction between the host and the template. The first two key methods deal with creating a template assembly: /// <summary> /// Creates an instance of the RazorHost with various options applied. /// Applies basic namespace imports and the name of the class to generate /// </summary> /// <param name="generatedNamespace"></param> /// <param name="generatedClass"></param> /// <returns></returns> protected RazorTemplateEngine CreateHost(string generatedNamespace, string generatedClass) { Type baseClassType = typeof(TBaseTemplateType); RazorEngineHost host = new RazorEngineHost(new CSharpRazorCodeLanguage()); host.DefaultBaseClass = baseClassType.FullName; host.DefaultClassName = generatedClass; host.DefaultNamespace = generatedNamespace; host.NamespaceImports.Add("System"); host.NamespaceImports.Add("System.Text"); host.NamespaceImports.Add("System.Collections.Generic"); host.NamespaceImports.Add("System.Linq"); host.NamespaceImports.Add("System.IO"); return new RazorTemplateEngine(host); } /// <summary> /// Parses and compiles a markup template into an assembly and returns /// an assembly name. The name is an ID that can be passed to /// ExecuteTemplateByAssembly which picks up a cached instance of the /// loaded assembly. /// /// </summary> /// <param name="namespaceOfGeneratedClass">The namespace of the class to generate from the template</param> /// <param name="generatedClassName">The name of the class to generate from the template</param> /// <param name="ReferencedAssemblies">Any referenced assemblies by dll name only. Assemblies must be in execution path of host or in GAC.</param> /// <param name="templateSourceReader">Textreader that loads the template</param> /// <remarks> /// The actual assembly isn't returned here to allow for cross-AppDomain /// operation. If the assembly was returned it would fail for cross-AppDomain /// calls. /// </remarks> /// <returns>An assembly Id. The Assembly is cached in memory and can be used with RenderFromAssembly.</returns> public string ParseAndCompileTemplate( string namespaceOfGeneratedClass, string generatedClassName, string[] ReferencedAssemblies, TextReader templateSourceReader) { RazorTemplateEngine engine = CreateHost(namespaceOfGeneratedClass, generatedClassName); // Generate the template class as CodeDom GeneratorResults razorResults = engine.GenerateCode(templateSourceReader); // Create code from the codeDom and compile CSharpCodeProvider codeProvider = new CSharpCodeProvider(); CodeGeneratorOptions options = new CodeGeneratorOptions(); // Capture Code Generated as a string for error info // and debugging LastGeneratedCode = null; using (StringWriter writer = new StringWriter()) { codeProvider.GenerateCodeFromCompileUnit(razorResults.GeneratedCode, writer, options); LastGeneratedCode = writer.ToString(); } CompilerParameters compilerParameters = new CompilerParameters(ReferencedAssemblies); // Standard Assembly References compilerParameters.ReferencedAssemblies.Add("System.dll"); compilerParameters.ReferencedAssemblies.Add("System.Core.dll"); compilerParameters.ReferencedAssemblies.Add("Microsoft.CSharp.dll"); // dynamic support! // Also add the current assembly so RazorTemplateBase is available compilerParameters.ReferencedAssemblies.Add(Assembly.GetExecutingAssembly().CodeBase.Substring(8)); compilerParameters.GenerateInMemory = Configuration.CompileToMemory; if (!Configuration.CompileToMemory) compilerParameters.OutputAssembly = Path.Combine(Configuration.TempAssemblyPath, "_" + Guid.NewGuid().ToString("n") + ".dll"); CompilerResults compilerResults = codeProvider.CompileAssemblyFromDom(compilerParameters, razorResults.GeneratedCode); if (compilerResults.Errors.Count > 0) { var compileErrors = new StringBuilder(); foreach (System.CodeDom.Compiler.CompilerError compileError in compilerResults.Errors) compileErrors.Append(String.Format(Resources.LineX0TColX1TErrorX2RN, compileError.Line, compileError.Column, compileError.ErrorText)); this.SetError(compileErrors.ToString() + "\r\n" + LastGeneratedCode); return null; } AssemblyCache.Add(compilerResults.CompiledAssembly.FullName, compilerResults.CompiledAssembly); return compilerResults.CompiledAssembly.FullName; } Think of the internal CreateHost() method as setting up the assembly generated from each template. Each template compiles into a separate assembly. It sets up namespaces, and assembly references, the base class used and the name and namespace for the generated class. ParseAndCompileTemplate() then calls the CreateHost() method to receive the template engine generator which effectively generates a CodeDom from the template – the template is turned into .NET code. The code generated from our earlier example looks something like this: //------------------------------------------------------------------------------ // <auto-generated> // This code was generated by a tool. // Runtime Version:4.0.30319.1 // // Changes to this file may cause incorrect behavior and will be lost if // the code is regenerated. // </auto-generated> //------------------------------------------------------------------------------ namespace RazorTest { using System; using System.Text; using System.Collections.Generic; using System.Linq; using System.IO; using System.Reflection; public class RazorTemplate : RazorHosting.RazorTemplateBase { #line hidden public RazorTemplate() { } public override void Execute() { WriteLiteral("Hello "); Write(Context.FirstName); WriteLiteral("! Your entry was entered on: "); Write(Context.Entered); WriteLiteral("\r\n\r\n"); // Code block: Update the host Windows Form passed in through the context Context.WinForm.Text = "Hello World from Razor at " + DateTime.Now.ToString(); WriteLiteral("\r\nAppDomain Id:\r\n "); Write(AppDomain.CurrentDomain.FriendlyName); WriteLiteral("\r\n \r\nAssembly:\r\n "); Write(Assembly.GetExecutingAssembly().FullName); WriteLiteral("\r\n\r\nCode based output: \r\n"); // Write output with Response object from code string output = string.Empty; for (int i = 0; i < 10; i++) { output += i.ToString() + " "; } } } } Basically the template’s body is turned into code in an Execute method that is called. Internally the template’s Write method is fired to actually generate the output. Note that the class inherits from RazorTemplateBase which is the generic parameter I used to specify the base class when creating an instance in my RazorEngine host: var engine = new RazorEngine<RazorTemplateBase>(); This template class must be provided and it must implement an Execute() and Write() method. Beyond that you can create any class you chose and attach your own properties. My RazorTemplateBase class implementation is very simple: public class RazorTemplateBase : MarshalByRefObject, IDisposable { /// <summary> /// You can pass in a generic context object /// to use in your template code /// </summary> public dynamic Context { get; set; } /// <summary> /// Class that generates output. Currently ultra simple /// with only Response.Write() implementation. /// </summary> public RazorResponse Response { get; set; } public object HostContainer {get; set; } public object Engine { get; set; } public RazorTemplateBase() { Response = new RazorResponse(); } public virtual void Write(object value) { Response.Write(value); } public virtual void WriteLiteral(object value) { Response.Write(value); } /// <summary> /// Razor Parser implements this method /// </summary> public virtual void Execute() {} public virtual void Dispose() { if (Response != null) { Response.Dispose(); Response = null; } } } Razor fills in the Execute method when it generates its subclass and uses the Write() method to output content. As you can see I use a RazorResponse() class here to generate output. This isn’t necessary really, as you could use a StringBuilder or StringWriter() directly, but I prefer using Response object so I can extend the Response behavior as needed. The RazorResponse class is also very simple and merely acts as a wrapper around a TextWriter: public class RazorResponse : IDisposable { /// <summary> /// Internal text writer - default to StringWriter() /// </summary> public TextWriter Writer = new StringWriter(); public virtual void Write(object value) { Writer.Write(value); } public virtual void WriteLine(object value) { Write(value); Write("\r\n"); } public virtual void WriteFormat(string format, params object[] args) { Write(string.Format(format, args)); } public override string ToString() { return Writer.ToString(); } public virtual void Dispose() { Writer.Close(); } public virtual void SetTextWriter(TextWriter writer) { // Close original writer if (Writer != null) Writer.Close(); Writer = writer; } } The Rendering Methods of RazorEngine At this point I’ve talked about the assembly generation logic and the template implementation itself. What’s left is that once you’ve generated the assembly is to execute it. The code to do this is handled in the various RenderXXX methods of the RazorEngine class. Let’s look at the lowest level one of these which is RenderTemplateFromAssembly() and a couple of internal support methods that handle instantiating and invoking of the generated template method: public string RenderTemplateFromAssembly( string assemblyId, string generatedNamespace, string generatedClass, object context, TextWriter outputWriter) { this.SetError(); Assembly generatedAssembly = AssemblyCache[assemblyId]; if (generatedAssembly == null) { this.SetError(Resources.PreviouslyCompiledAssemblyNotFound); return null; } string className = generatedNamespace + "." + generatedClass; Type type; try { type = generatedAssembly.GetType(className); } catch (Exception ex) { this.SetError(Resources.UnableToCreateType + className + ": " + ex.Message); return null; } // Start with empty non-error response (if we use a writer) string result = string.Empty; using(TBaseTemplateType instance = InstantiateTemplateClass(type)) { if (instance == null) return null; if (outputWriter != null) instance.Response.SetTextWriter(outputWriter); if (!InvokeTemplateInstance(instance, context)) return null; // Capture string output if implemented and return // otherwise null is returned if (outputWriter == null) result = instance.Response.ToString(); } return result; } protected virtual TBaseTemplateType InstantiateTemplateClass(Type type) { TBaseTemplateType instance = Activator.CreateInstance(type) as TBaseTemplateType; if (instance == null) { SetError(Resources.CouldnTActivateTypeInstance + type.FullName); return null; } instance.Engine = this; // If a HostContainer was set pass that to the template too instance.HostContainer = this.HostContainer; return instance; } /// <summary> /// Internally executes an instance of the template, /// captures errors on execution and returns true or false /// </summary> /// <param name="instance">An instance of the generated template</param> /// <returns>true or false - check ErrorMessage for errors</returns> protected virtual bool InvokeTemplateInstance(TBaseTemplateType instance, object context) { try { instance.Context = context; instance.Execute(); } catch (Exception ex) { this.SetError(Resources.TemplateExecutionError + ex.Message); return false; } finally { // Must make sure Response is closed instance.Response.Dispose(); } return true; } The RenderTemplateFromAssembly method basically requires the namespace and class to instantate and creates an instance of the class using InstantiateTemplateClass(). It then invokes the method with InvokeTemplateInstance(). These two methods are broken out because they are re-used by various other rendering methods and also to allow subclassing and providing additional configuration tasks to set properties and pass values to templates at execution time. In the default mode instantiation sets the Engine and HostContainer (discussed later) so the template can call back into the template engine, and the context is set when the template method is invoked. The various RenderXXX methods use similar code although they create the assemblies first. If you’re after potentially cashing assemblies the method is the one to call and that’s exactly what the two HostContainer classes do. More on that in a minute, but before we get into HostContainers let’s talk about AppDomain hosting and the like. Running Templates in their own AppDomain With the RazorEngine class above, when a template is parsed into an assembly and executed the assembly is created (in memory or on disk – you can configure that) and cached in the current AppDomain. In .NET once an assembly has been loaded it can never be unloaded so if you’re loading lots of templates and at some time you want to release them there’s no way to do so. If however you load the assemblies in a separate AppDomain that new AppDomain can be unloaded and the assemblies loaded in it with it. In order to host the templates in a separate AppDomain the easiest thing to do is to run the entire RazorEngine in a separate AppDomain. Then all interaction occurs in the other AppDomain and no further changes have to be made. To facilitate this there is a RazorEngineFactory which has methods that can instantiate the RazorHost in a separate AppDomain as well as in the local AppDomain. The host creates the remote instance and then hangs on to it to keep it alive as well as providing methods to shut down the AppDomain and reload the engine. Sounds complicated but cross-AppDomain invocation is actually fairly easy to implement. Here’s some of the relevant code from the RazorEngineFactory class. Like the RazorEngine this class is generic and requires a template base type in the generic class name: public class RazorEngineFactory<TBaseTemplateType> where TBaseTemplateType : RazorTemplateBase Here are the key methods of interest: /// <summary> /// Creates an instance of the RazorHost in a new AppDomain. This /// version creates a static singleton that that is cached and you /// can call UnloadRazorHostInAppDomain to unload it. /// </summary> /// <returns></returns> public static RazorEngine<TBaseTemplateType> CreateRazorHostInAppDomain() { if (Current == null) Current = new RazorEngineFactory<TBaseTemplateType>(); return Current.GetRazorHostInAppDomain(); } public static void UnloadRazorHostInAppDomain() { if (Current != null) Current.UnloadHost(); Current = null; } /// <summary> /// Instance method that creates a RazorHost in a new AppDomain. /// This method requires that you keep the Factory around in /// order to keep the AppDomain alive and be able to unload it. /// </summary> /// <returns></returns> public RazorEngine<TBaseTemplateType> GetRazorHostInAppDomain() { LocalAppDomain = CreateAppDomain(null); if (LocalAppDomain == null) return null; /// Create the instance inside of the new AppDomain /// Note: remote domain uses local EXE's AppBasePath!!! RazorEngine<TBaseTemplateType> host = null; try { Assembly ass = Assembly.GetExecutingAssembly(); string AssemblyPath = ass.Location; host = (RazorEngine<TBaseTemplateType>) LocalAppDomain.CreateInstanceFrom(AssemblyPath, typeof(RazorEngine<TBaseTemplateType>).FullName).Unwrap(); } catch (Exception ex) { ErrorMessage = ex.Message; return null; } return host; } /// <summary> /// Internally creates a new AppDomain in which Razor templates can /// be run. /// </summary> /// <param name="appDomainName"></param> /// <returns></returns> private AppDomain CreateAppDomain(string appDomainName) { if (appDomainName == null) appDomainName = "RazorHost_" + Guid.NewGuid().ToString("n"); AppDomainSetup setup = new AppDomainSetup(); // *** Point at current directory setup.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory; AppDomain localDomain = AppDomain.CreateDomain(appDomainName, null, setup); return localDomain; } /// <summary> /// Allow unloading of the created AppDomain to release resources /// All internal resources in the AppDomain are released including /// in memory compiled Razor assemblies. /// </summary> public void UnloadHost() { if (this.LocalAppDomain != null) { AppDomain.Unload(this.LocalAppDomain); this.LocalAppDomain = null; } } The static CreateRazorHostInAppDomain() is the key method that startup code usually calls. It uses a Current singleton instance to an instance of itself that is created cross AppDomain and is kept alive because it’s static. GetRazorHostInAppDomain actually creates a cross-AppDomain instance which first creates a new AppDomain and then loads the RazorEngine into it. The remote Proxy instance is returned as a result to the method and can be used the same as a local instance. The code to run with a remote AppDomain is simple: private RazorEngine<RazorTemplateBase> CreateHost() { if (this.Host != null) return this.Host; // Use Static Methods - no error message if host doesn't load this.Host = RazorEngineFactory<RazorTemplateBase>.CreateRazorHostInAppDomain(); if (this.Host == null) { MessageBox.Show("Unable to load Razor Template Host", "Razor Hosting", MessageBoxButtons.OK, MessageBoxIcon.Exclamation); } return this.Host; } This code relies on a local reference of the Host which is kept around for the duration of the app (in this case a form reference). To use this you’d simply do: this.Host = CreateHost(); if (host == null) return; string result = host.RenderTemplate( this.txtSource.Text, new string[] { "System.Windows.Forms.dll", "Westwind.Utilities.dll" }, this.CustomContext); if (result == null) { MessageBox.Show(host.ErrorMessage, "Template Execution Error", MessageBoxButtons.OK, MessageBoxIcon.Exclamation); return; } this.txtResult.Text = result; Now all templates run in a remote AppDomain and can be unloaded with simple code like this: RazorEngineFactory<RazorTemplateBase>.UnloadRazorHostInAppDomain(); this.Host = null; One Step further – Providing a caching ‘Runtime’ Once we can load templates in a remote AppDomain we can add some additional functionality like assembly caching based on application specific features. One of my typical scenarios is to render templates out of a scripts folder. So all templates live in a folder and they change infrequently. So a Folder based host that can compile these templates once and then only recompile them if something changes would be ideal. Enter host containers which are basically wrappers around the RazorEngine<t> and RazorEngineFactory<t>. They provide additional logic for things like file caching based on changes on disk or string hashes for string based template inputs. The folder host also provides for partial rendering logic through a custom template base implementation. There’s a base implementation in RazorBaseHostContainer, which provides the basics for hosting a RazorEngine, which includes the ability to start and stop the engine, cache assemblies and add references: public abstract class RazorBaseHostContainer<TBaseTemplateType> : MarshalByRefObject where TBaseTemplateType : RazorTemplateBase, new() { public RazorBaseHostContainer() { UseAppDomain = true; GeneratedNamespace = "__RazorHost"; } /// <summary> /// Determines whether the Container hosts Razor /// in a separate AppDomain. Seperate AppDomain /// hosting allows unloading and releasing of /// resources. /// </summary> public bool UseAppDomain { get; set; } /// <summary> /// Base folder location where the AppDomain /// is hosted. By default uses the same folder /// as the host application. /// /// Determines where binary dependencies are /// found for assembly references. /// </summary> public string BaseBinaryFolder { get; set; } /// <summary> /// List of referenced assemblies as string values. /// Must be in GAC or in the current folder of the host app/ /// base BinaryFolder /// </summary> public List<string> ReferencedAssemblies = new List<string>(); /// <summary> /// Name of the generated namespace for template classes /// </summary> public string GeneratedNamespace {get; set; } /// <summary> /// Any error messages /// </summary> public string ErrorMessage { get; set; } /// <summary> /// Cached instance of the Host. Required to keep the /// reference to the host alive for multiple uses. /// </summary> public RazorEngine<TBaseTemplateType> Engine; /// <summary> /// Cached instance of the Host Factory - so we can unload /// the host and its associated AppDomain. /// </summary> protected RazorEngineFactory<TBaseTemplateType> EngineFactory; /// <summary> /// Keep track of each compiled assembly /// and when it was compiled. /// /// Use a hash of the string to identify string /// changes. /// </summary> protected Dictionary<int, CompiledAssemblyItem> LoadedAssemblies = new Dictionary<int, CompiledAssemblyItem>(); /// <summary> /// Call to start the Host running. Follow by a calls to RenderTemplate to /// render individual templates. Call Stop when done. /// </summary> /// <returns>true or false - check ErrorMessage on false </returns> public virtual bool Start() { if (Engine == null) { if (UseAppDomain) Engine = RazorEngineFactory<TBaseTemplateType>.CreateRazorHostInAppDomain(); else Engine = RazorEngineFactory<TBaseTemplateType>.CreateRazorHost(); Engine.Configuration.CompileToMemory = true; Engine.HostContainer = this; if (Engine == null) { this.ErrorMessage = EngineFactory.ErrorMessage; return false; } } return true; } /// <summary> /// Stops the Host and releases the host AppDomain and cached /// assemblies. /// </summary> /// <returns>true or false</returns> public bool Stop() { this.LoadedAssemblies.Clear(); RazorEngineFactory<RazorTemplateBase>.UnloadRazorHostInAppDomain(); this.Engine = null; return true; } … } This base class provides most of the mechanics to host the runtime, but no application specific implementation for rendering. There are rendering functions but they just call the engine directly and provide no caching – there’s no context to decide how to cache and reuse templates. The key methods are Start and Stop and their main purpose is to start a new AppDomain (optionally) and shut it down when requested. The RazorFolderHostContainer – Folder Based Runtime Hosting Let’s look at the more application specific RazorFolderHostContainer implementation which is defined like this: public class RazorFolderHostContainer : RazorBaseHostContainer<RazorTemplateFolderHost> Note that a customized RazorTemplateFolderHost class template is used for this implementation that supports partial rendering in form of a RenderPartial() method that’s available to templates. The folder host’s features are: Render templates based on a Template Base Path (a ‘virtual’ if you will) Cache compiled assemblies based on the relative path and file time stamp File changes on templates cause templates to be recompiled into new assemblies Support for partial rendering using base folder relative pathing As shown in the startup examples earlier host containers require some startup code with a HostContainer tied to a persistent property (like a Form property): // The base path for templates - templates are rendered with relative paths // based on this path. HostContainer.TemplatePath = Path.Combine(Environment.CurrentDirectory, TemplateBaseFolder); // Default output rendering disk location HostContainer.RenderingOutputFile = Path.Combine(HostContainer.TemplatePath, "__Preview.htm"); // Add any assemblies you want reference in your templates HostContainer.ReferencedAssemblies.Add("System.Windows.Forms.dll"); // Start up the host container HostContainer.Start(); Once that’s done, you can render templates with the host container: // Pass the template path for full filename seleted with OpenFile Dialog // relativepath is: subdir\file.cshtml or file.cshtml or ..\file.cshtml var relativePath = Utilities.GetRelativePath(fileName, HostContainer.TemplatePath); if (!HostContainer.RenderTemplate(relativePath, Context, HostContainer.RenderingOutputFile)) { MessageBox.Show("Error: " + HostContainer.ErrorMessage); return; } webBrowser1.Navigate("file://" + HostContainer.RenderingOutputFile); The most critical task of the RazorFolderHostContainer implementation is to retrieve a template from disk, compile and cache it and then deal with deciding whether subsequent requests need to re-compile the template or simply use a cached version. Internally the GetAssemblyFromFileAndCache() handles this task: /// <summary> /// Internally checks if a cached assembly exists and if it does uses it /// else creates and compiles one. Returns an assembly Id to be /// used with the LoadedAssembly list. /// </summary> /// <param name="relativePath"></param> /// <param name="context"></param> /// <returns></returns> protected virtual CompiledAssemblyItem GetAssemblyFromFileAndCache(string relativePath) { string fileName = Path.Combine(TemplatePath, relativePath).ToLower(); int fileNameHash = fileName.GetHashCode(); if (!File.Exists(fileName)) { this.SetError(Resources.TemplateFileDoesnTExist + fileName); return null; } CompiledAssemblyItem item = null; this.LoadedAssemblies.TryGetValue(fileNameHash, out item); string assemblyId = null; // Check for cached instance if (item != null) { var fileTime = File.GetLastWriteTimeUtc(fileName); if (fileTime <= item.CompileTimeUtc) assemblyId = item.AssemblyId; } else item = new CompiledAssemblyItem(); // No cached instance - create assembly and cache if (assemblyId == null) { string safeClassName = GetSafeClassName(fileName); StreamReader reader = null; try { reader = new StreamReader(fileName, true); } catch (Exception ex) { this.SetError(Resources.ErrorReadingTemplateFile + fileName); return null; } assemblyId = Engine.ParseAndCompileTemplate(this.ReferencedAssemblies.ToArray(), reader); // need to ensure reader is closed if (reader != null) reader.Close(); if (assemblyId == null) { this.SetError(Engine.ErrorMessage); return null; } item.AssemblyId = assemblyId; item.CompileTimeUtc = DateTime.UtcNow; item.FileName = fileName; item.SafeClassName = safeClassName; this.LoadedAssemblies[fileNameHash] = item; } return item; } This code uses a LoadedAssembly dictionary which is comprised of a structure that holds a reference to a compiled assembly, a full filename and file timestamp and an assembly id. LoadedAssemblies (defined on the base class shown earlier) is essentially a cache for compiled assemblies and they are identified by a hash id. In the case of files the hash is a GetHashCode() from the full filename of the template. The template is checked for in the cache and if not found the file stamp is checked. If that’s newer than the cache’s compilation date the template is recompiled otherwise the version in the cache is used. All the core work defers to a RazorEngine<T> instance to ParseAndCompileTemplate(). The three rendering specific methods then are rather simple implementations with just a few lines of code dealing with parameter and return value parsing: /// <summary> /// Renders a template to a TextWriter. Useful to write output into a stream or /// the Response object. Used for partial rendering. /// </summary> /// <param name="relativePath">Relative path to the file in the folder structure</param> /// <param name="context">Optional context object or null</param> /// <param name="writer">The textwriter to write output into</param> /// <returns></returns> public bool RenderTemplate(string relativePath, object context, TextWriter writer) { // Set configuration data that is to be passed to the template (any object) Engine.TemplatePerRequestConfigurationData = new RazorFolderHostTemplateConfiguration() { TemplatePath = Path.Combine(this.TemplatePath, relativePath), TemplateRelativePath = relativePath, }; CompiledAssemblyItem item = GetAssemblyFromFileAndCache(relativePath); if (item == null) { writer.Close(); return false; } try { // String result will be empty as output will be rendered into the // Response object's stream output. However a null result denotes // an error string result = Engine.RenderTemplateFromAssembly(item.AssemblyId, context, writer); if (result == null) { this.SetError(Engine.ErrorMessage); return false; } } catch (Exception ex) { this.SetError(ex.Message); return false; } finally { writer.Close(); } return true; } /// <summary> /// Render a template from a source file on disk to a specified outputfile. /// </summary> /// <param name="relativePath">Relative path off the template root folder. Format: path/filename.cshtml</param> /// <param name="context">Any object that will be available in the template as a dynamic of this.Context</param> /// <param name="outputFile">Optional - output file where output is written to. If not specified the /// RenderingOutputFile property is used instead /// </param> /// <returns>true if rendering succeeds, false on failure - check ErrorMessage</returns> public bool RenderTemplate(string relativePath, object context, string outputFile) { if (outputFile == null) outputFile = RenderingOutputFile; try { using (StreamWriter writer = new StreamWriter(outputFile, false, Engine.Configuration.OutputEncoding, Engine.Configuration.StreamBufferSize)) { return RenderTemplate(relativePath, context, writer); } } catch (Exception ex) { this.SetError(ex.Message); return false; } return true; } /// <summary> /// Renders a template to string. Useful for RenderTemplate /// </summary> /// <param name="relativePath"></param> /// <param name="context"></param> /// <returns></returns> public string RenderTemplateToString(string relativePath, object context) { string result = string.Empty; try { using (StringWriter writer = new StringWriter()) { // String result will be empty as output will be rendered into the // Response object's stream output. However a null result denotes // an error if (!RenderTemplate(relativePath, context, writer)) { this.SetError(Engine.ErrorMessage); return null; } result = writer.ToString(); } } catch (Exception ex) { this.SetError(ex.Message); return null; } return result; } The idea is that you can create custom host container implementations that do exactly what you want fairly easily. Take a look at both the RazorFolderHostContainer and RazorStringHostContainer classes for the basic concepts you can use to create custom implementations. Notice also that you can set the engine’s PerRequestConfigurationData() from the host container: // Set configuration data that is to be passed to the template (any object) Engine.TemplatePerRequestConfigurationData = new RazorFolderHostTemplateConfiguration() { TemplatePath = Path.Combine(this.TemplatePath, relativePath), TemplateRelativePath = relativePath, }; which when set to a non-null value is passed to the Template’s InitializeTemplate() method. This method receives an object parameter which you can cast as needed: public override void InitializeTemplate(object configurationData) { // Pick up configuration data and stuff into Request object RazorFolderHostTemplateConfiguration config = configurationData as RazorFolderHostTemplateConfiguration; this.Request.TemplatePath = config.TemplatePath; this.Request.TemplateRelativePath = config.TemplateRelativePath; } With this data you can then configure any custom properties or objects on your main template class. It’s an easy way to pass data from the HostContainer all the way down into the template. The type you use is of type object so you have to cast it yourself, and it must be serializable since it will likely run in a separate AppDomain. This might seem like an ugly way to pass data around – normally I’d use an event delegate to call back from the engine to the host, but since this is running over AppDomain boundaries events get really tricky and passing a template instance back up into the host over AppDomain boundaries doesn’t work due to serialization issues. So it’s easier to pass the data from the host down into the template using this rather clumsy approach of set and forward. It’s ugly, but it’s something that can be hidden in the host container implementation as I’ve done here. It’s also not something you have to do in every implementation so this is kind of an edge case, but I know I’ll need to pass a bunch of data in some of my applications and this will be the easiest way to do so. Summing Up Hosting the Razor runtime is something I got jazzed up about quite a bit because I have an immediate need for this type of templating/merging/scripting capability in an application I’m working on. I’ve also been using templating in many apps and it’s always been a pain to deal with. The Razor engine makes this whole experience a lot cleaner and more light weight and with these wrappers I can now plug .NET based templating into my code literally with a few lines of code. That’s something to cheer about… I hope some of you will find this useful as well… Resources The examples and code require that you download the Razor runtimes. Projects are for Visual Studio 2010 running on .NET 4.0 Platform Installer 3.0 (install WebMatrix or MVC 3 for Razor Runtimes) Latest Code in Subversion Repository Download Snapshot of the Code Documentation (CHM Help File) © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  .NET  

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  • HTG Reviews the CODE Keyboard: Old School Construction Meets Modern Amenities

    - by Jason Fitzpatrick
    There’s nothing quite as satisfying as the smooth and crisp action of a well built keyboard. If you’re tired of  mushy keys and cheap feeling keyboards, a well-constructed mechanical keyboard is a welcome respite from the $10 keyboard that came with your computer. Read on as we put the CODE mechanical keyboard through the paces. What is the CODE Keyboard? The CODE keyboard is a collaboration between manufacturer WASD Keyboards and Jeff Atwood of Coding Horror (the guy behind the Stack Exchange network and Discourse forum software). Atwood’s focus was incorporating the best of traditional mechanical keyboards and the best of modern keyboard usability improvements. In his own words: The world is awash in terrible, crappy, no name how-cheap-can-we-make-it keyboards. There are a few dozen better mechanical keyboard options out there. I’ve owned and used at least six different expensive mechanical keyboards, but I wasn’t satisfied with any of them, either: they didn’t have backlighting, were ugly, had terrible design, or were missing basic functions like media keys. That’s why I originally contacted Weyman Kwong of WASD Keyboards way back in early 2012. I told him that the state of keyboards was unacceptable to me as a geek, and I proposed a partnership wherein I was willing to work with him to do whatever it takes to produce a truly great mechanical keyboard. Even the ardent skeptic who questions whether Atwood has indeed created a truly great mechanical keyboard certainly can’t argue with the position he starts from: there are so many agonizingly crappy keyboards out there. Even worse, in our opinion, is that unless you’re a typist of a certain vintage there’s a good chance you’ve never actually typed on a really nice keyboard. Those that didn’t start using computers until the mid-to-late 1990s most likely have always typed on modern mushy-key keyboards and never known the joy of typing on a really responsive and crisp mechanical keyboard. Is our preference for and love of mechanical keyboards shining through here? Good. We’re not even going to try and hide it. So where does the CODE keyboard stack up in pantheon of keyboards? Read on as we walk you through the simple setup and our experience using the CODE. Setting Up the CODE Keyboard Although the setup of the CODE keyboard is essentially plug and play, there are two distinct setup steps that you likely haven’t had to perform on a previous keyboard. Both highlight the degree of care put into the keyboard and the amount of customization available. Inside the box you’ll find the keyboard, a micro USB cable, a USB-to-PS2 adapter, and a tool which you may be unfamiliar with: a key puller. We’ll return to the key puller in a moment. Unlike the majority of keyboards on the market, the cord isn’t permanently affixed to the keyboard. What does this mean for you? Aside from the obvious need to plug it in yourself, it makes it dead simple to repair your own keyboard cord if it gets attacked by a pet, mangled in a mechanism on your desk, or otherwise damaged. It also makes it easy to take advantage of the cable routing channels in on the underside of the keyboard to  route your cable exactly where you want it. While we’re staring at the underside of the keyboard, check out those beefy rubber feet. By peripherals standards they’re huge (and there is six instead of the usual four). Once you plunk the keyboard down where you want it, it might as well be glued down the rubber feet work so well. After you’ve secured the cable and adjusted it to your liking, there is one more task  before plug the keyboard into the computer. On the bottom left-hand side of the keyboard, you’ll find a small recess in the plastic with some dip switches inside: The dip switches are there to switch hardware functions for various operating systems, keyboard layouts, and to enable/disable function keys. By toggling the dip switches you can change the keyboard from QWERTY mode to Dvorak mode and Colemak mode, the two most popular alternative keyboard configurations. You can also use the switches to enable Mac-functionality (for Command/Option keys). One of our favorite little toggles is the SW3 dip switch: you can disable the Caps Lock key; goodbye accidentally pressing Caps when you mean to press Shift. You can review the entire dip switch configuration chart here. The quick-start for Windows users is simple: double check that all the switches are in the off position (as seen in the photo above) and then simply toggle SW6 on to enable the media and backlighting function keys (this turns the menu key on the keyboard into a function key as typically found on laptop keyboards). After adjusting the dip switches to your liking, plug the keyboard into an open USB port on your computer (or into your PS/2 port using the included adapter). Design, Layout, and Backlighting The CODE keyboard comes in two flavors, a traditional 87-key layout (no number pad) and a traditional 104-key layout (number pad on the right hand side). We identify the layout as traditional because, despite some modern trapping and sneaky shortcuts, the actual form factor of the keyboard from the shape of the keys to the spacing and position is as classic as it comes. You won’t have to learn a new keyboard layout and spend weeks conditioning yourself to a smaller than normal backspace key or a PgUp/PgDn pair in an unconventional location. Just because the keyboard is very conventional in layout, however, doesn’t mean you’ll be missing modern amenities like media-control keys. The following additional functions are hidden in the F11, F12, Pause button, and the 2×6 grid formed by the Insert and Delete rows: keyboard illumination brightness, keyboard illumination on/off, mute, and then the typical play/pause, forward/backward, stop, and volume +/- in Insert and Delete rows, respectively. While we weren’t sure what we’d think of the function-key system at first (especially after retiring a Microsoft Sidewinder keyboard with a huge and easily accessible volume knob on it), it took less than a day for us to adapt to using the Fn key, located next to the right Ctrl key, to adjust our media playback on the fly. Keyboard backlighting is a largely hit-or-miss undertaking but the CODE keyboard nails it. Not only does it have pleasant and easily adjustable through-the-keys lighting but the key switches the keys themselves are attached to are mounted to a steel plate with white paint. Enough of the light reflects off the interior cavity of the keys and then diffuses across the white plate to provide nice even illumination in between the keys. Highlighting the steel plate beneath the keys brings us to the actual construction of the keyboard. It’s rock solid. The 87-key model, the one we tested, is 2.0 pounds. The 104-key is nearly a half pound heavier at 2.42 pounds. Between the steel plate, the extra-thick PCB board beneath the steel plate, and the thick ABS plastic housing, the keyboard has very solid feel to it. Combine that heft with the previously mentioned thick rubber feet and you have a tank-like keyboard that won’t budge a millimeter during normal use. Examining The Keys This is the section of the review the hardcore typists and keyboard ninjas have been waiting for. We’ve looked at the layout of the keyboard, we’ve looked at the general construction of it, but what about the actual keys? There are a wide variety of keyboard construction techniques but the vast majority of modern keyboards use a rubber-dome construction. The key is floated in a plastic frame over a rubber membrane that has a little rubber dome for each key. The press of the physical key compresses the rubber dome downwards and a little bit of conductive material on the inside of the dome’s apex connects with the circuit board. Despite the near ubiquity of the design, many people dislike it. The principal complaint is that dome keyboards require a complete compression to register a keystroke; keyboard designers and enthusiasts refer to this as “bottoming out”. In other words, the register the “b” key, you need to completely press that key down. As such it slows you down and requires additional pressure and movement that, over the course of tens of thousands of keystrokes, adds up to a whole lot of wasted time and fatigue. The CODE keyboard features key switches manufactured by Cherry, a company that has manufactured key switches since the 1960s. Specifically the CODE features Cherry MX Clear switches. These switches feature the same classic design of the other Cherry switches (such as the MX Blue and Brown switch lineups) but they are significantly quieter (yes this is a mechanical keyboard, but no, your neighbors won’t think you’re firing off a machine gun) as they lack the audible click found in most Cherry switches. This isn’t to say that they keyboard doesn’t have a nice audible key press sound when the key is fully depressed, but that the key mechanism isn’t doesn’t create a loud click sound when triggered. One of the great features of the Cherry MX clear is a tactile “bump” that indicates the key has been compressed enough to register the stroke. For touch typists the very subtle tactile feedback is a great indicator that you can move on to the next stroke and provides a welcome speed boost. Even if you’re not trying to break any word-per-minute records, that little bump when pressing the key is satisfying. The Cherry key switches, in addition to providing a much more pleasant typing experience, are also significantly more durable than dome-style key switch. Rubber dome switch membrane keyboards are typically rated for 5-10 million contacts whereas the Cherry mechanical switches are rated for 50 million contacts. You’d have to write the next War and Peace  and follow that up with A Tale of Two Cities: Zombie Edition, and then turn around and transcribe them both into a dozen different languages to even begin putting a tiny dent in the lifecycle of this keyboard. So what do the switches look like under the classicly styled keys? You can take a look yourself with the included key puller. Slide the loop between the keys and then gently beneath the key you wish to remove: Wiggle the key puller gently back and forth while exerting a gentle upward pressure to pop the key off; You can repeat the process for every key, if you ever find yourself needing to extract piles of cat hair, Cheeto dust, or other foreign objects from your keyboard. There it is, the naked switch, the source of that wonderful crisp action with the tactile bump on each keystroke. The last feature worthy of a mention is the N-key rollover functionality of the keyboard. This is a feature you simply won’t find on non-mechanical keyboards and even gaming keyboards typically only have any sort of key roller on the high-frequency keys like WASD. So what is N-key rollover and why do you care? On a typical mass-produced rubber-dome keyboard you cannot simultaneously press more than two keys as the third one doesn’t register. PS/2 keyboards allow for unlimited rollover (in other words you can’t out type the keyboard as all of your keystrokes, no matter how fast, will register); if you use the CODE keyboard with the PS/2 adapter you gain this ability. If you don’t use the PS/2 adapter and use the native USB, you still get 6-key rollover (and the CTRL, ALT, and SHIFT don’t count towards the 6) so realistically you still won’t be able to out type the computer as even the more finger twisting keyboard combos and high speed typing will still fall well within the 6-key rollover. The rollover absolutely doesn’t matter if you’re a slow hunt-and-peck typist, but if you’ve read this far into a keyboard review there’s a good chance that you’re a serious typist and that kind of quality construction and high-number key rollover is a fantastic feature.  The Good, The Bad, and the Verdict We’ve put the CODE keyboard through the paces, we’ve played games with it, typed articles with it, left lengthy comments on Reddit, and otherwise used and abused it like we would any other keyboard. The Good: The construction is rock solid. In an emergency, we’re confident we could use the keyboard as a blunt weapon (and then resume using it later in the day with no ill effect on the keyboard). The Cherry switches are an absolute pleasure to type on; the Clear variety found in the CODE keyboard offer a really nice middle-ground between the gun-shot clack of a louder mechanical switch and the quietness of a lesser-quality dome keyboard without sacrificing quality. Touch typists will love the subtle tactile bump feedback. Dip switch system makes it very easy for users on different systems and with different keyboard layout needs to switch between operating system and keyboard layouts. If you’re investing a chunk of change in a keyboard it’s nice to know you can take it with you to a different operating system or “upgrade” it to a new layout if you decide to take up Dvorak-style typing. The backlighting is perfect. You can adjust it from a barely-visible glow to a blazing light-up-the-room brightness. Whatever your intesity preference, the white-coated steel backplate does a great job diffusing the light between the keys. You can easily remove the keys for cleaning (or to rearrange the letters to support a new keyboard layout). The weight of the unit combined with the extra thick rubber feet keep it planted exactly where you place it on the desk. The Bad: While you’re getting your money’s worth, the $150 price tag is a shock when compared to the $20-60 price tags you find on lower-end keyboards. People used to large dedicated media keys independent of the traditional key layout (such as the large buttons and volume controls found on many modern keyboards) might be off put by the Fn-key style media controls on the CODE. The Verdict: The keyboard is clearly and heavily influenced by the needs of serious typists. Whether you’re a programmer, transcriptionist, or just somebody that wants to leave the lengthiest article comments the Internet has ever seen, the CODE keyboard offers a rock solid typing experience. Yes, $150 isn’t pocket change, but the quality of the CODE keyboard is so high and the typing experience is so enjoyable, you’re easily getting ten times the value you’d get out of purchasing a lesser keyboard. Even compared to other mechanical keyboards on the market, like the Das Keyboard, you’re still getting more for your money as other mechanical keyboards don’t come with the lovely-to-type-on Cherry MX Clear switches, back lighting, and hardware-based operating system keyboard layout switching. If it’s in your budget to upgrade your keyboard (especially if you’ve been slogging along with a low-end rubber-dome keyboard) there’s no good reason to not pickup a CODE keyboard. Key animation courtesy of Geekhack.org user Lethal Squirrel.       

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  • SQLAuthority News – TechEd India – April 12-14, 2010 Bangalore – An Unforgettable Experience – An Op

    - by pinaldave
    TechEd India was one of the largest Technology events in India led by Microsoft. This event was attended by more than 3,000 technology enthusiasts, making it one of the most well-organized events of the year. Though I attempted to attend almost all the technology events here, I have not seen any bigger or better event in Indian subcontinents other than this. There are 21 Technical Tracks at Tech·Ed India 2010 that span more than 745 learning opportunities. I was fortunate enough to be a part of this whole event as a speaker and a delegate, as well. TechEd India Speaker Badge and A Token of Lifetime Hotel Selection I presented three different sessions at TechEd India and was also a part of panel discussion. (The details of the sessions are given at the end of this blog post.) Due to extensive traveling, I stay away from my family occasionally. For this reason, I took my wife – Nupur and daughter Shaivi (8 months old) to the event along with me. We stayed at the same hotel where the event was organized so as to maximize my time bonding with my family and to have more time in networking with technology community, at the same time. The hotel Lalit Ashok is the largest and most luxurious venue one can find in Bangalore, located in the middle of the city. The cost of the hotel was a bit pricey, but looking at all the advantages, I had decided to ask for a booking there. Hotel Lalit Ashok Nupur Dave and Shaivi Dave Arrival Day – DAY 0 – April 11, 2010 I reached the event a day earlier, and that was one wise decision for I was able to relax a bit and go over my presentation for the next day’s course. I am a kind of person who likes to get everything ready ahead of time. I was also able to enjoy a pleasant evening with several Microsoft employees and my family friends. I even checked out the location where I would be doing presentations the next day. I was fortunate enough to meet Bijoy Singhal from Microsoft who helped me out with a few of the logistics issues that occured the day before. I was not aware of the fact that the very next day he was going to be “The Man” of the TechEd 2010 event. Vinod Kumar from Microsoft was really very kind as he talked to me regarding my subsequent session. He gave me some suggestions which were really helpful that I was able to incorporate them during my presentation. Finally, I was able to meet Abhishek Kant from Microsoft; his valuable suggestions and unlimited passion have inspired many people like me to work with the Community. Pradipta from Microsoft was also around, being extremely busy with logistics; however, in those busy times, he did find some good spare time to have a chat with me and the other Community leaders. I also met Harish Ranganathan and Sachin Rathi, both from Microsoft. It was so interesting to listen to both of them talking about SharePoint. I just have no words to express my overwhelmed spirit because of all these passionate young guys - Pradipta,Vinod, Bijoy, Harish, Sachin and Ahishek (of course!). Map of TechEd India 2010 Event Day 1 – April 12, 2010 From morning until night time, today was truly a very busy day for me. I had two presentations and one panel discussion for the day. Needless to say, I had a few meetings to attend as well. The day started with a keynote from S. Somaseger where he announced the launch of Visual Studio 2010. The keynote area was really eye-catching because of the very large, bigger-than- life uniform screen. This was truly one to show. The title music of the keynote was very interesting and it featured Bijoy Singhal as the model. It was interesting to talk to him afterwards, when we laughed at jokes together about his modeling assignment. TechEd India Keynote Opening Featuring Bijoy TechEd India 2010 Keynote – S. Somasegar Time: 11:15pm – 11:45pm Session 1: True Lies of SQL Server – SQL Myth Buster Following the excellent keynote, I had my very first session on the subject of SQL Server Myth Buster. At first, I was a bit nervous as right after the keynote, for this was my very first session and during my presentation I saw lots of Microsoft Product Team members. Well, it really went well and I had a really good discussion with attendees of the session. I felt that a well begin was half-done and my confidence was regained. Right after the session, I met a few of my Community friends and had meaningful discussions with them on many subjects. The abstract of the session is as follows: In this 30-minute demo session, I am going to briefly demonstrate few SQL Server Myths and their resolutions as I back them up with some demo. This demo presentation is a must-attend for all developers and administrators who would come to the event. This is going to be a very quick yet fun session. Pinal Presenting session at TechEd India 2010 Time: 1:00 PM – 2:00 PM Lunch with Somasegar After the session I went to see my daughter, and then I headed right away to the lunch with S. Somasegar – the keynote speaker and senior vice president of the Developer Division at Microsoft. I really thank to Abhishek who made it possible for us. Because of his efforts, all the MVPs had the opportunity to meet such a legendary person and had to talk with them on Microsoft Technology. Though Somasegar is currently holding such a high position in Microsoft, he is very polite and a real gentleman, and how I wish that everybody in industry is like him. Believe me, if you spread love and kindness, then that is what you will receive back. As soon as lunch time was over, I ran to the session hall as my second presentation was about to start. Time: 2:30pm – 3:30pm Session 2: Master Data Services in Microsoft SQL Server 2008 R2 Business Intelligence is a subject which was widely talked about at TechEd. Everybody was interested in this subject, and I did not excuse myself from this great concept as well. I consider myself fortunate as I was presenting on the subject of Master Data Services at TechEd. When I had initially learned this subject, I had a bit of confusion about the usage of this tool. Later on, I decided that I would tackle about how we all developers and DBAs are not able to understand something so simple such as this, and even worst, creating confusion about the technology. During system designing, it is very important to have a reference material or master lookup tables. Well, I talked about the same subject and presented the session keeping that as my center talk. The session went very well and I received lots of interesting questions. I got many compliments for talking about this subject on the real-life scenario. I really thank Rushabh Mehta (CEO, Solid Quality Mentors India) for his supportive suggestions that helped me prepare the slide deck, as well as the subject. Pinal Presenting session at TechEd India 2010 The abstract of the session is as follows: SQL Server Master Data Services will ship with SQL Server 2008 R2 and will improve Microsoft’s platform appeal. This session provides an in-depth demonstration of MDS features and highlights important usage scenarios. Master Data Services enables consistent decision-making process by allowing you to create, manage and propagate changes from a single master view of your business entities. Also, MDS – Master Data-hub which is a vital component, helps ensure the consistency of reporting across systems and deliver faster and more accurate results across the enterprise. We will talk about establishing the basis for a centralized approach to defining, deploying, and managing master data in the enterprise. Pinal Presenting session at TechEd India 2010 The day was still not over for me. I had ran into several friends but we were not able keep our enthusiasm under control about all the rumors saying that SQL Server 2008 R2 was about to be launched tomorrow in the keynote. I then ran to my third and final technical event for the day- a panel discussion with the top technologies of India. Time: 5:00pm – 6:00pm Panel Discussion: Harness the power of Web – SEO and Technical Blogging As I have delivered two technical sessions by this time, I was a bit tired but  not less enthusiastic when I had to talk about Blog and Technology. We discussed many different topics there. I told them that the most important aspect for any blog is its content. We discussed in depth the issues with plagiarism and how to avoid it. Another topic of discussion was how we technology bloggers can create awareness in the Community about what the right kind of blogging is and what morally and technically wrong acts are. A couple of questions were raised about what type of liberty a person can have in terms of writing blogs. Well, it was generically agreed that a blog is mainly a representation of our ideas and thoughts; it should not be governed by external entities. As long as one is writing what they really want to say, but not providing incorrect information or not practicing plagiarism, a blogger should be allowed to express himself. This panel discussion was supposed to be over in an hour, but the interest of the participants was remarkable and so it was extended for 30 minutes more. Finally, we decided to bring to a close the discussion and agreed that we will continue the topic next year. TechEd India Panel Discussion on Web, Technology and SEO Surprisingly, the day was just beginning after doing all of these. By this time, I have almost met all the MVP who arrived at the event, as well as many Microsoft employees. There were lots of Community folks present, too. I decided that I would go to meet several friends from the Community and continue to communicate with me on SQLAuthority.com. I also met Abhishek Baxi and had a good talk with him regarding Win Mobile and Twitter. He also took a very quick video of me wherein I spoke in my mother’s tongue, Gujarati. It was funny that I talked in Gujarati almost all the day, but when I was talking in the interview I could not find the right Gujarati words to speak. I think we all think in English when we think about Technology, so as to address universality. After meeting them, I headed towards the Speakers’ Dinner. Time: 8:00 PM – onwards Speakers Dinner The Speakers’ dinner was indeed a wonderful opportunity for all the speakers to get together and relax. We talked so many different things, from XBOX to Hindi Movies, and from SQL to Samosas. I just could not express how much fun I had. After a long evening, when I returned tmy room and met Shaivi, I just felt instantly relaxed. Kids are really gifts from God. Today was a really long but exciting day. So many things happened in just one day: Visual Studio Lanch, lunch with Somasegar, 2 technical sessions, 1 panel discussion, community leaders meeting, speakers dinner and, last but not leas,t playing with my child! A perfect day! Day 2 – April 13, 2010 Today started with a bang with the excellent keynote by Kamal Hathi who launched SQL Server 2008 R2 in India and demonstrated the power of PowerPivot to all of us. 101 Million Rows in Excel brought lots of applause from the audience. Kamal Hathi Presenting Keynote at TechEd India 2010 The day was a bit easier one for me. I had no sessions today and no events planned. I had a few meetings planned for the second day of the event. I sat in the speaker’s lounge for half a day and met many people there. I attended nearly 9 different meetings today. The subjects of the meetings were very different. Here is a list of the topics of the Community-related meetings: SQL PASS and its involvement in India and subcontinents How to start community blogging Forums and developing aptitude towards technology Ahmedabad/Gandhinagar User Groups and their developments SharePoint and SQL Business Meeting – a client meeting Business Meeting – a potential performance tuning project Business Meeting – Solid Quality Mentors (SolidQ) And family friends Pinal Dave at TechEd India The day passed by so quickly during this meeting. In the evening, I headed to Partners Expo with friends and checked out few of the booths. I really wanted to talk about some of the products, but due to the freebies there was so much crowd that I finally decided to just take the contact details of the partner. I will now start sending them with my queries and, hopefully, I will have my questions answered. Nupur and Shaivi had also one meeting to attend; it was with our family friend Vijay Raj. Vijay is also a person who loves Technology and loves it more than anybody. I see him growing and learning every day, but still remaining as a ‘human’. I believe that if someone acquires as much knowledge as him, that person will become either a computer or cyborg. Here, Vijay is still a kind gentleman and is able to stay as our close family friend. Shaivi was really happy to play with Uncle Vijay. Pinal Dave and Vijay Raj Renuka Prasad, a Microsoft MVP, impressed me with his passion and knowledge of SQL. Every time he gives me credit for his success, I believe that he is very humble. He has way more certifications than me and has worked many more years with SQL compared to me. He is an excellent photographer as well. Most of the photos in this blog post have been taken by him. I told him if ever he wants to do a part time job, he can do the photography very well. Pinal Dave and Renuka Prasad I also met L Srividya from Microsoft, whom I was looking forward to meet. She is a bundle of knowledge that everyone would surely learn a lot from her. I was able to get a few minutes from her and well, I felt confident. She enlightened me with SQL Server BI concepts, domain management and SQL Server security and few other interesting details. I also had a wonderful time talking about SharePoint with fellow Solid Quality Mentor Joy Rathnayake. He is very passionate about SharePoint but when you talk .NET and SQL with him, he is still overwhelmingly knowledgeable. In fact, while talking to him, I figured out that the recent training he delivered was on SQL Server 2008 R2. I told him a joke that it hurts my ego as he is more popular now in SQL training and consulting than me. I am sure all of you agree that working with good people is a gift from God. I am fortunate enough to work with the best of the best Industry experts. It was a great pleasure to hang out with my Community friends – Ahswin Kini, HimaBindu Vejella, Vasudev G, Suprotim Agrawal, Dhananjay, Vikram Pendse, Mahesh Dhola, Mahesh Mitkari,  Manu Zacharia, Shobhan, Hardik Shah, Ashish Mohta, Manan, Subodh Sohani and Sanjay Shetty (of course!) .  (Please let me know if I have met you at the event and forgot your name to list here). Time: 8:00 PM – onwards Community Leaders Dinner After lots of meetings, I headed towards the Community Leaders dinner meeting and met almost all the folks I met in morning. The discussion was almost the same but the real good thing was that we were enjoying it. The food was really good. Nupur was invited in the event, but Shaivi could not come. When Nupur tried to enter the event, she was stopped as Shaivi did not have the pass to enter the dinner. Nupur expressed that Shaivi is only 8 months old and does not eat outside food as well and could not stay by herself at this age, but the door keeper did not agree and asked that without the entry details Shaivi could not go in, but Nupur could. Nupur called me on phone and asked me to help her out. By the time, I was outside; the organizer of the event reached to the door and happily approved Shaivi to join the party. Once in the party, Shaivi had lots of fun meeting so many people. Shaivi Dave and Abhishek Kant Dean Guida (Infragistics President and CEO) and Pinal Dave (SQLAuthority.com) Day 3 – April 14, 2010 Though, it was last day, I was very much excited today as I was about to present my very favorite session. Query Optimization and Performance Tuning is my domain expertise and I make my leaving by consulting and training the same. Today’s session was on the same subject and as an additional twist, another subject about Spatial Database was presented. I was always intrigued with Spatial Database and I have enjoyed learning about it; however, I have never thought about Spatial Indexing before it was decided that I will do this session. I really thank Solid Quality Mentor Dr. Greg Low for his assistance in helping me prepare the slide deck and also review the content. Furthermore, today was really what I call my ‘learning day’ . So far I had not attended any session in TechEd and I felt a bit down for that. Everybody spends their valuable time & money to learn something new and exciting in TechEd and I had not attended a single session at the moment thinking that it was already last day of the event. I did have a plan for the day and I attended two technical sessions before my session of spatial database. I attended 2 sessions of Vinod Kumar. Vinod is a natural storyteller and there was no doubt that his sessions would be jam-packed. People attended his sessions simply because Vinod is syhe speaker. He did not have a single time disappointed audience; he is truly a good speaker. He knows his stuff very well. I personally do not think that in India he can be compared to anyone for SQL. Time: 12:30pm-1:30pm SQL Server Query Optimization, Execution and Debugging Query Performance I really had a fun time attending this session. Vinod made this session very interactive. The entire audience really got into the presentation and started participating in the event. Vinod was presenting a small problem with Query Tuning, which any developer would have encountered and solved with their help in such a fashion that a developer feels he or she have already resolved it. In one question, I was the only one who was ready to answer and Vinod told me in a light tone that I am now allowed to answer it! The audience really found it very amusing. There was a huge crowd around Vinod after the session. Vinod – A master storyteller! Time: 3:45pm-4:45pm Data Recovery / consistency with CheckDB This session was much heavier than the earlier one, and I must say this is my most favorite session I EVER attended in India. In this TechEd I have only attended two sessions, but in my career, I have attended numerous technical sessions not only in India, but all over the world. This session had taken my breath away. One by one, Vinod took the different databases, and started to corrupt them in different ways. Each database has some unique ways to get corrupted. Once that was done, Vinod started to show the DBCC CEHCKDB and demonstrated how it can solve your problem. He finally fixed all the databases with this single tool. I do have a good knowledge of this subject, but let me honestly admit that I have learned a lot from this session. I enjoyed and cheered during this session along with other attendees. I had total satisfaction that, just like everyone, I took advantage of the event and learned something. I am now TECHnically EDucated. Pinal Dave and Vinod Kumar After two very interactive and informative SQL Sessions from Vinod Kumar, the next turn me presenting on Spatial Database and Indexing. I got once again nervous but Vinod told me to stay natural and do my presentation. Well, once I got a huge stage with a total of four projectors and a large crowd, I felt better. Time: 5:00pm-6:00pm Session 3: Developing with SQL Server Spatial and Deep Dive into Spatial Indexing Pinal Presenting session at TechEd India 2010 Pinal Presenting session at TechEd India 2010 I kicked off this session with Michael J Swart‘s beautiful spatial image. This session was the last one for the day but, to my surprise, I had more than 200+ attendees. Slowly, the rain was starting outside and I was worried that the hall would not be full; despite this, there was not a single seat available in the first five minutes of the session. Thanks to all of you for attending my presentation. I had demonstrated the map of world (and India) and quickly explained what  Geographic and Geometry data types in Spatial Database are. This session had interesting story of Indexing and Comparison, as well as how different traditional indexes are from spatial indexing. Pinal Presenting session at TechEd India 2010 Due to the heavy rain during this event, the power went off for about 22 minutes (just an accident – nobodies fault). During these minutes, there were no audio, no video and no light. I continued to address the mass of 200+ people without any audio device and PowerPoint. I must thank the audience because not a single person left from the session. They all stayed in their place, some moved closure to listen to me properly. I noticed that the curiosity and eagerness to learn new things was at the peak even though it was the very last session of the TechEd. Everybody wanted get the maximum knowledge out of this whole event. I was touched by the support from audience. They listened and participated in my session even without any kinds of technology (no ppt, no mike, no AC, nothing). During these 22 minutes, I had completed my theory verbally. Pinal Presenting session at TechEd India 2010 After a while, we got the projector back online and we continued with some exciting demos. Many thanks to Microsoft people who worked energetically in background to get the backup power for project up. I had a very interesting demo wherein I overlaid Bangalore and Hyderabad on the India Map and find their aerial distance between them. After finding the aerial distance, we browsed online and found that SQL Server estimates the exact aerial distance between these two cities, as compared to the factual distance. There was a huge applause from the crowd on the subject that SQL Server takes into the count of the curvature of the earth and finds the precise distances based on details. During the process of finding the distance, I demonstrated a few examples of the indexes where I expressed how one can use those indexes to find these distances and how they can improve the performance of similar query. I also demonstrated few examples wherein we were able to see in which data type the Index is most useful. We finished the demos with a few more internal stuff. Pinal Presenting session at TechEd India 2010 Despite all issues, I was mostly satisfied with my presentation. I think it was the best session I have ever presented at any conference. There was no help from Technology for a while, but I still got lots of appreciation at the end. When we ended the session, the applause from the audience was so loud that for a moment, the rain was not audible. I was truly moved by the dedication of the Technology enthusiasts. Pinal Dave After Presenting session at TechEd India 2010 The abstract of the session is as follows: The Microsoft SQL Server 2008 delivers new spatial data types that enable you to consume, use, and extend location-based data through spatial-enabled applications. Attend this session to learn how to use spatial functionality in next version of SQL Server to build and optimize spatial queries. This session outlines the new geography data type to store geodetic spatial data and perform operations on it, use the new geometry data type to store planar spatial data and perform operations on it, take advantage of new spatial indexes for high performance queries, use the new spatial results tab to quickly and easily view spatial query results directly from within Management Studio, extend spatial data capabilities by building or integrating location-enabled applications through support for spatial standards and specifications and much more. Time: 8:00 PM – onwards Dinner by Sponsors After the lively session during the day, there was another dinner party courtesy of one of the sponsors of TechEd. All the MVPs and several Community leaders were present at the dinner. I would like to express my gratitude to Abhishek Kant for organizing this wonderful event for us. It was a blast and really relaxing in all angles. We all stayed there for a long time and talked about our sweet and unforgettable memories of the event. Pinal Dave and Bijoy Singhal It was really one wonderful event. After writing this much, I say that I have no words to express about how much I enjoyed TechEd. However, it is true that I shared with you only 1% of the total activities I have done at the event. There were so many people I have met, yet were not mentioned here although I wanted to write their names here, too . Anyway, I have learned so many things and up until now, I am not able to get over all the fun I had in this event. Pinal Dave at TechEd India 2010 The Next Days – April 15, 2010 – till today I am still not able to get my mind out of the whole experience I had at TechEd India 2010. It was like a whole Microsoft Family working together to celebrate a happy occasion. TechEd India – Truly An Unforgettable Experience! Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: About Me, MVP, Pinal Dave, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, SQLServer, T SQL, Technology Tagged: TechEd, TechEdIn

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  • Agile Development

    - by James Oloo Onyango
    Alot of literature has and is being written about agile developement and its surrounding philosophies. In my quest to find the best way to express the importance of agile methodologies, i have found Robert C. Martin's "A Satire Of Two Companies" to be both the most concise and thorough! Enjoy the read! Rufus Inc Project Kick Off Your name is Bob. The date is January 3, 2001, and your head still aches from the recent millennial revelry. You are sitting in a conference room with several managers and a group of your peers. You are a project team leader. Your boss is there, and he has brought along all of his team leaders. His boss called the meeting. "We have a new project to develop," says your boss's boss. Call him BB. The points in his hair are so long that they scrape the ceiling. Your boss's points are just starting to grow, but he eagerly awaits the day when he can leave Brylcream stains on the acoustic tiles. BB describes the essence of the new market they have identified and the product they want to develop to exploit this market. "We must have this new project up and working by fourth quarter October 1," BB demands. "Nothing is of higher priority, so we are cancelling your current project." The reaction in the room is stunned silence. Months of work are simply going to be thrown away. Slowly, a murmur of objection begins to circulate around the conference table.   His points give off an evil green glow as BB meets the eyes of everyone in the room. One by one, that insidious stare reduces each attendee to quivering lumps of protoplasm. It is clear that he will brook no discussion on this matter. Once silence has been restored, BB says, "We need to begin immediately. How long will it take you to do the analysis?" You raise your hand. Your boss tries to stop you, but his spitwad misses you and you are unaware of his efforts.   "Sir, we can't tell you how long the analysis will take until we have some requirements." "The requirements document won't be ready for 3 or 4 weeks," BB says, his points vibrating with frustration. "So, pretend that you have the requirements in front of you now. How long will you require for analysis?" No one breathes. Everyone looks around to see whether anyone has some idea. "If analysis goes beyond April 1, we have a problem. Can you finish the analysis by then?" Your boss visibly gathers his courage: "We'll find a way, sir!" His points grow 3 mm, and your headache increases by two Tylenol. "Good." BB smiles. "Now, how long will it take to do the design?" "Sir," you say. Your boss visibly pales. He is clearly worried that his 3 mms are at risk. "Without an analysis, it will not be possible to tell you how long design will take." BB's expression shifts beyond austere.   "PRETEND you have the analysis already!" he says, while fixing you with his vacant, beady little eyes. "How long will it take you to do the design?" Two Tylenol are not going to cut it. Your boss, in a desperate attempt to save his new growth, babbles: "Well, sir, with only six months left to complete the project, design had better take no longer than 3 months."   "I'm glad you agree, Smithers!" BB says, beaming. Your boss relaxes. He knows his points are secure. After a while, he starts lightly humming the Brylcream jingle. BB continues, "So, analysis will be complete by April 1, design will be complete by July 1, and that gives you 3 months to implement the project. This meeting is an example of how well our new consensus and empowerment policies are working. Now, get out there and start working. I'll expect to see TQM plans and QIT assignments on my desk by next week. Oh, and don't forget that your crossfunctional team meetings and reports will be needed for next month's quality audit." "Forget the Tylenol," you think to yourself as you return to your cubicle. "I need bourbon."   Visibly excited, your boss comes over to you and says, "Gosh, what a great meeting. I think we're really going to do some world shaking with this project." You nod in agreement, too disgusted to do anything else. "Oh," your boss continues, "I almost forgot." He hands you a 30-page document. "Remember that the SEI is coming to do an evaluation next week. This is the evaluation guide. You need to read through it, memorize it, and then shred it. It tells you how to answer any questions that the SEI auditors ask you. It also tells you what parts of the building you are allowed to take them to and what parts to avoid. We are determined to be a CMM level 3 organization by June!"   You and your peers start working on the analysis of the new project. This is difficult because you have no requirements. But from the 10-minute introduction given by BB on that fateful morning, you have some idea of what the product is supposed to do.   Corporate process demands that you begin by creating a use case document. You and your team begin enumerating use cases and drawing oval and stick diagrams. Philosophical debates break out among the team members. There is disagreement as to whether certain use cases should be connected with <<extends>> or <<includes>> relationships. Competing models are created, but nobody knows how to evaluate them. The debate continues, effectively paralyzing progress.   After a week, somebody finds the iceberg.com Web site, which recommends disposing entirely of <<extends>> and <<includes>> and replacing them with <<precedes>> and <<uses>>. The documents on this Web site, authored by Don Sengroiux, describes a method known as stalwart-analysis, which claims to be a step-by-step method for translating use cases into design diagrams. More competing use case models are created using this new scheme, but again, people can't agree on how to evaluate them. The thrashing continues. More and more, the use case meetings are driven by emotion rather than by reason. If it weren't for the fact that you don't have requirements, you'd be pretty upset by the lack of progress you are making. The requirements document arrives on February 15. And then again on February 20, 25, and every week thereafter. Each new version contradicts the previous one. Clearly, the marketing folks who are writing the requirements, empowered though they might be, are not finding consensus.   At the same time, several new competing use case templates have been proposed by the various team members. Each template presents its own particularly creative way of delaying progress. The debates rage on. On March 1, Prudence Putrigence, the process proctor, succeeds in integrating all the competing use case forms and templates into a single, all-encompassing form. Just the blank form is 15 pages long. She has managed to include every field that appeared on all the competing templates. She also presents a 159- page document describing how to fill out the use case form. All current use cases must be rewritten according to the new standard.   You marvel to yourself that it now requires 15 pages of fill-in-the-blank and essay questions to answer the question: What should the system do when the user presses Return? The corporate process (authored by L. E. Ott, famed author of "Holistic Analysis: A Progressive Dialectic for Software Engineers") insists that you discover all primary use cases, 87 percent of all secondary use cases, and 36.274 percent of all tertiary use cases before you can complete analysis and enter the design phase. You have no idea what a tertiary use case is. So in an attempt to meet this requirement, you try to get your use case document reviewed by the marketing department, which you hope will know what a tertiary use case is.   Unfortunately, the marketing folks are too busy with sales support to talk to you. Indeed, since the project started, you have not been able to get a single meeting with marketing, which has provided a never-ending stream of changing and contradictory requirements documents.   While one team has been spinning endlessly on the use case document, another team has been working out the domain model. Endless variations of UML documents are pouring out of this team. Every week, the model is reworked.   The team members can't decide whether to use <<interfaces>> or <<types>> in the model. A huge disagreement has been raging on the proper syntax and application of OCL. Others on the team just got back from a 5-day class on catabolism, and have been producing incredibly detailed and arcane diagrams that nobody else can fathom.   On March 27, with one week to go before analysis is to be complete, you have produced a sea of documents and diagrams but are no closer to a cogent analysis of the problem than you were on January 3. **** And then, a miracle happens.   **** On Saturday, April 1, you check your e-mail from home. You see a memo from your boss to BB. It states unequivocally that you are done with the analysis! You phone your boss and complain. "How could you have told BB that we were done with the analysis?" "Have you looked at a calendar lately?" he responds. "It's April 1!" The irony of that date does not escape you. "But we have so much more to think about. So much more to analyze! We haven't even decided whether to use <<extends>> or <<precedes>>!" "Where is your evidence that you are not done?" inquires your boss, impatiently. "Whaaa . . . ." But he cuts you off. "Analysis can go on forever; it has to be stopped at some point. And since this is the date it was scheduled to stop, it has been stopped. Now, on Monday, I want you to gather up all existing analysis materials and put them into a public folder. Release that folder to Prudence so that she can log it in the CM system by Monday afternoon. Then get busy and start designing."   As you hang up the phone, you begin to consider the benefits of keeping a bottle of bourbon in your bottom desk drawer. They threw a party to celebrate the on-time completion of the analysis phase. BB gave a colon-stirring speech on empowerment. And your boss, another 3 mm taller, congratulated his team on the incredible show of unity and teamwork. Finally, the CIO takes the stage to tell everyone that the SEI audit went very well and to thank everyone for studying and shredding the evaluation guides that were passed out. Level 3 now seems assured and will be awarded by June. (Scuttlebutt has it that managers at the level of BB and above are to receive significant bonuses once the SEI awards level 3.)   As the weeks flow by, you and your team work on the design of the system. Of course, you find that the analysis that the design is supposedly based on is flawedno, useless; no, worse than useless. But when you tell your boss that you need to go back and work some more on the analysis to shore up its weaker sections, he simply states, "The analysis phase is over. The only allowable activity is design. Now get back to it."   So, you and your team hack the design as best you can, unsure of whether the requirements have been properly analyzed. Of course, it really doesn't matter much, since the requirements document is still thrashing with weekly revisions, and the marketing department still refuses to meet with you.     The design is a nightmare. Your boss recently misread a book named The Finish Line in which the author, Mark DeThomaso, blithely suggested that design documents should be taken down to code-level detail. "If we are going to be working at that level of detail," you ask, "why don't we simply write the code instead?" "Because then you wouldn't be designing, of course. And the only allowable activity in the design phase is design!" "Besides," he continues, "we have just purchased a companywide license for Dandelion! This tool enables 'Round the Horn Engineering!' You are to transfer all design diagrams into this tool. It will automatically generate our code for us! It will also keep the design diagrams in sync with the code!" Your boss hands you a brightly colored shrinkwrapped box containing the Dandelion distribution. You accept it numbly and shuffle off to your cubicle. Twelve hours, eight crashes, one disk reformatting, and eight shots of 151 later, you finally have the tool installed on your server. You consider the week your team will lose while attending Dandelion training. Then you smile and think, "Any week I'm not here is a good week." Design diagram after design diagram is created by your team. Dandelion makes it very difficult to draw these diagrams. There are dozens and dozens of deeply nested dialog boxes with funny text fields and check boxes that must all be filled in correctly. And then there's the problem of moving classes between packages. At first, these diagram are driven from the use cases. But the requirements are changing so often that the use cases rapidly become meaningless. Debates rage about whether VISITOR or DECORATOR design patterns should be used. One developer refuses to use VISITOR in any form, claiming that it's not a properly object-oriented construct. Someone refuses to use multiple inheritance, since it is the spawn of the devil. Review meetings rapidly degenerate into debates about the meaning of object orientation, the definition of analysis versus design, or when to use aggregation versus association. Midway through the design cycle, the marketing folks announce that they have rethought the focus of the system. Their new requirements document is completely restructured. They have eliminated several major feature areas and replaced them with feature areas that they anticipate customer surveys will show to be more appropriate. You tell your boss that these changes mean that you need to reanalyze and redesign much of the system. But he says, "The analysis phase is system. But he says, "The analysis phase is over. The only allowable activity is design. Now get back to it."   You suggest that it might be better to create a simple prototype to show to the marketing folks and even some potential customers. But your boss says, "The analysis phase is over. The only allowable activity is design. Now get back to it." Hack, hack, hack, hack. You try to create some kind of a design document that might reflect the new requirements documents. However, the revolution of the requirements has not caused them to stop thrashing. Indeed, if anything, the wild oscillations of the requirements document have only increased in frequency and amplitude.   You slog your way through them.   On June 15, the Dandelion database gets corrupted. Apparently, the corruption has been progressive. Small errors in the DB accumulated over the months into bigger and bigger errors. Eventually, the CASE tool just stopped working. Of course, the slowly encroaching corruption is present on all the backups. Calls to the Dandelion technical support line go unanswered for several days. Finally, you receive a brief e-mail from Dandelion, informing you that this is a known problem and that the solution is to purchase the new version, which they promise will be ready some time next quarter, and then reenter all the diagrams by hand.   ****   Then, on July 1 another miracle happens! You are done with the design!   Rather than go to your boss and complain, you stock your middle desk drawer with some vodka.   **** They threw a party to celebrate the on-time completion of the design phase and their graduation to CMM level 3. This time, you find BB's speech so stirring that you have to use the restroom before it begins. New banners and plaques are all over your workplace. They show pictures of eagles and mountain climbers, and they talk about teamwork and empowerment. They read better after a few scotches. That reminds you that you need to clear out your file cabinet to make room for the brandy. You and your team begin to code. But you rapidly discover that the design is lacking in some significant areas. Actually, it's lacking any significance at all. You convene a design session in one of the conference rooms to try to work through some of the nastier problems. But your boss catches you at it and disbands the meeting, saying, "The design phase is over. The only allowable activity is coding. Now get back to it."   ****   The code generated by Dandelion is really hideous. It turns out that you and your team were using association and aggregation the wrong way, after all. All the generated code has to be edited to correct these flaws. Editing this code is extremely difficult because it has been instrumented with ugly comment blocks that have special syntax that Dandelion needs in order to keep the diagrams in sync with the code. If you accidentally alter one of these comments, the diagrams will be regenerated incorrectly. It turns out that "Round the Horn Engineering" requires an awful lot of effort. The more you try to keep the code compatible with Dandelion, the more errors Dandelion generates. In the end, you give up and decide to keep the diagrams up to date manually. A second later, you decide that there's no point in keeping the diagrams up to date at all. Besides, who has time?   Your boss hires a consultant to build tools to count the number of lines of code that are being produced. He puts a big thermometer graph on the wall with the number 1,000,000 on the top. Every day, he extends the red line to show how many lines have been added. Three days after the thermometer appears on the wall, your boss stops you in the hall. "That graph isn't growing quickly enough. We need to have a million lines done by October 1." "We aren't even sh-sh-sure that the proshect will require a m-million linezh," you blather. "We have to have a million lines done by October 1," your boss reiterates. His points have grown again, and the Grecian formula he uses on them creates an aura of authority and competence. "Are you sure your comment blocks are big enough?" Then, in a flash of managerial insight, he says, "I have it! I want you to institute a new policy among the engineers. No line of code is to be longer than 20 characters. Any such line must be split into two or more preferably more. All existing code needs to be reworked to this standard. That'll get our line count up!"   You decide not to tell him that this will require two unscheduled work months. You decide not to tell him anything at all. You decide that intravenous injections of pure ethanol are the only solution. You make the appropriate arrangements. Hack, hack, hack, and hack. You and your team madly code away. By August 1, your boss, frowning at the thermometer on the wall, institutes a mandatory 50-hour workweek.   Hack, hack, hack, and hack. By September 1st, the thermometer is at 1.2 million lines and your boss asks you to write a report describing why you exceeded the coding budget by 20 percent. He institutes mandatory Saturdays and demands that the project be brought back down to a million lines. You start a campaign of remerging lines. Hack, hack, hack, and hack. Tempers are flaring; people are quitting; QA is raining trouble reports down on you. Customers are demanding installation and user manuals; salespeople are demanding advance demonstrations for special customers; the requirements document is still thrashing, the marketing folks are complaining that the product isn't anything like they specified, and the liquor store won't accept your credit card anymore. Something has to give.    On September 15, BB calls a meeting. As he enters the room, his points are emitting clouds of steam. When he speaks, the bass overtones of his carefully manicured voice cause the pit of your stomach to roll over. "The QA manager has told me that this project has less than 50 percent of the required features implemented. He has also informed me that the system crashes all the time, yields wrong results, and is hideously slow. He has also complained that he cannot keep up with the continuous train of daily releases, each more buggy than the last!" He stops for a few seconds, visibly trying to compose himself. "The QA manager estimates that, at this rate of development, we won't be able to ship the product until December!" Actually, you think it's more like March, but you don't say anything. "December!" BB roars with such derision that people duck their heads as though he were pointing an assault rifle at them. "December is absolutely out of the question. Team leaders, I want new estimates on my desk in the morning. I am hereby mandating 65-hour work weeks until this project is complete. And it better be complete by November 1."   As he leaves the conference room, he is heard to mutter: "Empowermentbah!" * * * Your boss is bald; his points are mounted on BB's wall. The fluorescent lights reflecting off his pate momentarily dazzle you. "Do you have anything to drink?" he asks. Having just finished your last bottle of Boone's Farm, you pull a bottle of Thunderbird from your bookshelf and pour it into his coffee mug. "What's it going to take to get this project done? " he asks. "We need to freeze the requirements, analyze them, design them, and then implement them," you say callously. "By November 1?" your boss exclaims incredulously. "No way! Just get back to coding the damned thing." He storms out, scratching his vacant head.   A few days later, you find that your boss has been transferred to the corporate research division. Turnover has skyrocketed. Customers, informed at the last minute that their orders cannot be fulfilled on time, have begun to cancel their orders. Marketing is re-evaluating whether this product aligns with the overall goals of the company. Memos fly, heads roll, policies change, and things are, overall, pretty grim. Finally, by March, after far too many sixty-five hour weeks, a very shaky version of the software is ready. In the field, bug-discovery rates are high, and the technical support staff are at their wits' end, trying to cope with the complaints and demands of the irate customers. Nobody is happy.   In April, BB decides to buy his way out of the problem by licensing a product produced by Rupert Industries and redistributing it. The customers are mollified, the marketing folks are smug, and you are laid off.     Rupert Industries: Project Alpha   Your name is Robert. The date is January 3, 2001. The quiet hours spent with your family this holiday have left you refreshed and ready for work. You are sitting in a conference room with your team of professionals. The manager of the division called the meeting. "We have some ideas for a new project," says the division manager. Call him Russ. He is a high-strung British chap with more energy than a fusion reactor. He is ambitious and driven but understands the value of a team. Russ describes the essence of the new market opportunity the company has identified and introduces you to Jane, the marketing manager, who is responsible for defining the products that will address it. Addressing you, Jane says, "We'd like to start defining our first product offering as soon as possible. When can you and your team meet with me?" You reply, "We'll be done with the current iteration of our project this Friday. We can spare a few hours for you between now and then. After that, we'll take a few people from the team and dedicate them to you. We'll begin hiring their replacements and the new people for your team immediately." "Great," says Russ, "but I want you to understand that it is critical that we have something to exhibit at the trade show coming up this July. If we can't be there with something significant, we'll lose the opportunity."   "I understand," you reply. "I don't yet know what it is that you have in mind, but I'm sure we can have something by July. I just can't tell you what that something will be right now. In any case, you and Jane are going to have complete control over what we developers do, so you can rest assured that by July, you'll have the most important things that can be accomplished in that time ready to exhibit."   Russ nods in satisfaction. He knows how this works. Your team has always kept him advised and allowed him to steer their development. He has the utmost confidence that your team will work on the most important things first and will produce a high-quality product.   * * *   "So, Robert," says Jane at their first meeting, "How does your team feel about being split up?" "We'll miss working with each other," you answer, "but some of us were getting pretty tired of that last project and are looking forward to a change. So, what are you people cooking up?" Jane beams. "You know how much trouble our customers currently have . . ." And she spends a half hour or so describing the problem and possible solution. "OK, wait a second" you respond. "I need to be clear about this." And so you and Jane talk about how this system might work. Some of her ideas aren't fully formed. You suggest possible solutions. She likes some of them. You continue discussing.   During the discussion, as each new topic is addressed, Jane writes user story cards. Each card represents something that the new system has to do. The cards accumulate on the table and are spread out in front of you. Both you and Jane point at them, pick them up, and make notes on them as you discuss the stories. The cards are powerful mnemonic devices that you can use to represent complex ideas that are barely formed.   At the end of the meeting, you say, "OK, I've got a general idea of what you want. I'm going to talk to the team about it. I imagine they'll want to run some experiments with various database structures and presentation formats. Next time we meet, it'll be as a group, and we'll start identifying the most important features of the system."   A week later, your nascent team meets with Jane. They spread the existing user story cards out on the table and begin to get into some of the details of the system. The meeting is very dynamic. Jane presents the stories in the order of their importance. There is much discussion about each one. The developers are concerned about keeping the stories small enough to estimate and test. So they continually ask Jane to split one story into several smaller stories. Jane is concerned that each story have a clear business value and priority, so as she splits them, she makes sure that this stays true.   The stories accumulate on the table. Jane writes them, but the developers make notes on them as needed. Nobody tries to capture everything that is said; the cards are not meant to capture everything but are simply reminders of the conversation.   As the developers become more comfortable with the stories, they begin writing estimates on them. These estimates are crude and budgetary, but they give Jane an idea of what the story will cost.   At the end of the meeting, it is clear that many more stories could be discussed. It is also clear that the most important stories have been addressed and that they represent several months worth of work. Jane closes the meeting by taking the cards with her and promising to have a proposal for the first release in the morning.   * * *   The next morning, you reconvene the meeting. Jane chooses five cards and places them on the table. "According to your estimates, these cards represent about one perfect team-week's worth of work. The last iteration of the previous project managed to get one perfect team-week done in 3 real weeks. If we can get these five stories done in 3 weeks, we'll be able to demonstrate them to Russ. That will make him feel very comfortable about our progress." Jane is pushing it. The sheepish look on her face lets you know that she knows it too. You reply, "Jane, this is a new team, working on a new project. It's a bit presumptuous to expect that our velocity will be the same as the previous team's. However, I met with the team yesterday afternoon, and we all agreed that our initial velocity should, in fact, be set to one perfectweek for every 3 real-weeks. So you've lucked out on this one." "Just remember," you continue, "that the story estimates and the story velocity are very tentative at this point. We'll learn more when we plan the iteration and even more when we implement it."   Jane looks over her glasses at you as if to say "Who's the boss around here, anyway?" and then smiles and says, "Yeah, don't worry. I know the drill by now."Jane then puts 15 more cards on the table. She says, "If we can get all these cards done by the end of March, we can turn the system over to our beta test customers. And we'll get good feedback from them."   You reply, "OK, so we've got our first iteration defined, and we have the stories for the next three iterations after that. These four iterations will make our first release."   "So," says Jane, can you really do these five stories in the next 3 weeks?" "I don't know for sure, Jane," you reply. "Let's break them down into tasks and see what we get."   So Jane, you, and your team spend the next several hours taking each of the five stories that Jane chose for the first iteration and breaking them down into small tasks. The developers quickly realize that some of the tasks can be shared between stories and that other tasks have commonalities that can probably be taken advantage of. It is clear that potential designs are popping into the developers' heads. From time to time, they form little discussion knots and scribble UML diagrams on some cards.   Soon, the whiteboard is filled with the tasks that, once completed, will implement the five stories for this iteration. You start the sign-up process by saying, "OK, let's sign up for these tasks." "I'll take the initial database generation." Says Pete. "That's what I did on the last project, and this doesn't look very different. I estimate it at two of my perfect workdays." "OK, well, then, I'll take the login screen," says Joe. "Aw, darn," says Elaine, the junior member of the team, "I've never done a GUI, and kinda wanted to try that one."   "Ah, the impatience of youth," Joe says sagely, with a wink in your direction. "You can assist me with it, young Jedi." To Jane: "I think it'll take me about three of my perfect workdays."   One by one, the developers sign up for tasks and estimate them in terms of their own perfect workdays. Both you and Jane know that it is best to let the developers volunteer for tasks than to assign the tasks to them. You also know full well that you daren't challenge any of the developers' estimates. You know these people, and you trust them. You know that they are going to do the very best they can.   The developers know that they can't sign up for more perfect workdays than they finished in the last iteration they worked on. Once each developer has filled his or her schedule for the iteration, they stop signing up for tasks.   Eventually, all the developers have stopped signing up for tasks. But, of course, tasks are still left on the board.   "I was worried that that might happen," you say, "OK, there's only one thing to do, Jane. We've got too much to do in this iteration. What stories or tasks can we remove?" Jane sighs. She knows that this is the only option. Working overtime at the beginning of a project is insane, and projects where she's tried it have not fared well.   So Jane starts to remove the least-important functionality. "Well, we really don't need the login screen just yet. We can simply start the system in the logged-in state." "Rats!" cries Elaine. "I really wanted to do that." "Patience, grasshopper." says Joe. "Those who wait for the bees to leave the hive will not have lips too swollen to relish the honey." Elaine looks confused. Everyone looks confused. "So . . .," Jane continues, "I think we can also do away with . . ." And so, bit by bit, the list of tasks shrinks. Developers who lose a task sign up for one of the remaining ones.   The negotiation is not painless. Several times, Jane exhibits obvious frustration and impatience. Once, when tensions are especially high, Elaine volunteers, "I'll work extra hard to make up some of the missing time." You are about to correct her when, fortunately, Joe looks her in the eye and says, "When once you proceed down the dark path, forever will it dominate your destiny."   In the end, an iteration acceptable to Jane is reached. It's not what Jane wanted. Indeed, it is significantly less. But it's something the team feels that can be achieved in the next 3 weeks.   And, after all, it still addresses the most important things that Jane wanted in the iteration. "So, Jane," you say when things had quieted down a bit, "when can we expect acceptance tests from you?" Jane sighs. This is the other side of the coin. For every story the development team implements,   Jane must supply a suite of acceptance tests that prove that it works. And the team needs these long before the end of the iteration, since they will certainly point out differences in the way Jane and the developers imagine the system's behaviour.   "I'll get you some example test scripts today," Jane promises. "I'll add to them every day after that. You'll have the entire suite by the middle of the iteration."   * * *   The iteration begins on Monday morning with a flurry of Class, Responsibilities, Collaborators sessions. By midmorning, all the developers have assembled into pairs and are rapidly coding away. "And now, my young apprentice," Joe says to Elaine, "you shall learn the mysteries of test-first design!"   "Wow, that sounds pretty rad," Elaine replies. "How do you do it?" Joe beams. It's clear that he has been anticipating this moment. "OK, what does the code do right now?" "Huh?" replied Elaine, "It doesn't do anything at all; there is no code."   "So, consider our task; can you think of something the code should do?" "Sure," Elaine said with youthful assurance, "First, it should connect to the database." "And thereupon, what must needs be required to connecteth the database?" "You sure talk weird," laughed Elaine. "I think we'd have to get the database object from some registry and call the Connect() method. "Ah, astute young wizard. Thou perceives correctly that we requireth an object within which we can cacheth the database object." "Is 'cacheth' really a word?" "It is when I say it! So, what test can we write that we know the database registry should pass?" Elaine sighs. She knows she'll just have to play along. "We should be able to create a database object and pass it to the registry in a Store() method. And then we should be able to pull it out of the registry with a Get() method and make sure it's the same object." "Oh, well said, my prepubescent sprite!" "Hay!" "So, now, let's write a test function that proves your case." "But shouldn't we write the database object and registry object first?" "Ah, you've much to learn, my young impatient one. Just write the test first." "But it won't even compile!" "Are you sure? What if it did?" "Uh . . ." "Just write the test, Elaine. Trust me." And so Joe, Elaine, and all the other developers began to code their tasks, one test case at a time. The room in which they worked was abuzz with the conversations between the pairs. The murmur was punctuated by an occasional high five when a pair managed to finish a task or a difficult test case.   As development proceeded, the developers changed partners once or twice a day. Each developer got to see what all the others were doing, and so knowledge of the code spread generally throughout the team.   Whenever a pair finished something significant whether a whole task or simply an important part of a task they integrated what they had with the rest of the system. Thus, the code base grew daily, and integration difficulties were minimized.   The developers communicated with Jane on a daily basis. They'd go to her whenever they had a question about the functionality of the system or the interpretation of an acceptance test case.   Jane, good as her word, supplied the team with a steady stream of acceptance test scripts. The team read these carefully and thereby gained a much better understanding of what Jane expected the system to do. By the beginning of the second week, there was enough functionality to demonstrate to Jane. She watched eagerly as the demonstration passed test case after test case. "This is really cool," Jane said as the demonstration finally ended. "But this doesn't seem like one-third of the tasks. Is your velocity slower than anticipated?"   You grimace. You'd been waiting for a good time to mention this to Jane but now she was forcing the issue. "Yes, unfortunately, we are going more slowly than we had expected. The new application server we are using is turning out to be a pain to configure. Also, it takes forever to reboot, and we have to reboot it whenever we make even the slightest change to its configuration."   Jane eyes you with suspicion. The stress of last Monday's negotiations had still not entirely dissipated. She says, "And what does this mean to our schedule? We can't slip it again, we just can't. Russ will have a fit! He'll haul us all into the woodshed and ream us some new ones."   You look Jane right in the eyes. There's no pleasant way to give someone news like this. So you just blurt out, "Look, if things keep going like they're going, we're not going to be done with everything by next Friday. Now it's possible that we'll figure out a way to go faster. But, frankly, I wouldn't depend on that. You should start thinking about one or two tasks that could be removed from the iteration without ruining the demonstration for Russ. Come hell or high water, we are going to give that demonstration on Friday, and I don't think you want us to choose which tasks to omit."   "Aw forchrisakes!" Jane barely manages to stifle yelling that last word as she stalks away, shaking her head. Not for the first time, you say to yourself, "Nobody ever promised me project management would be easy." You are pretty sure it won't be the last time, either.   Actually, things went a bit better than you had hoped. The team did, in fact, have to drop one task from the iteration, but Jane had chosen wisely, and the demonstration for Russ went without a hitch. Russ was not impressed with the progress, but neither was he dismayed. He simply said, "This is pretty good. But remember, we have to be able to demonstrate this system at the trade show in July, and at this rate, it doesn't look like you'll have all that much to show." Jane, whose attitude had improved dramatically with the completion of the iteration, responded to Russ by saying, "Russ, this team is working hard, and well. When July comes around, I am confident that we'll have something significant to demonstrate. It won't be everything, and some of it may be smoke and mirrors, but we'll have something."   Painful though the last iteration was, it had calibrated your velocity numbers. The next iteration went much better. Not because your team got more done than in the last iteration but simply because the team didn't have to remove any tasks or stories in the middle of the iteration.   By the start of the fourth iteration, a natural rhythm has been established. Jane, you, and the team know exactly what to expect from one another. The team is running hard, but the pace is sustainable. You are confident that the team can keep up this pace for a year or more.   The number of surprises in the schedule diminishes to near zero; however, the number of surprises in the requirements does not. Jane and Russ frequently look over the growing system and make recommendations or changes to the existing functionality. But all parties realize that these changes take time and must be scheduled. So the changes do not cause anyone's expectations to be violated. In March, there is a major demonstration of the system to the board of directors. The system is very limited and is not yet in a form good enough to take to the trade show, but progress is steady, and the board is reasonably impressed.   The second release goes even more smoothly than the first. By now, the team has figured out a way to automate Jane's acceptance test scripts. The team has also refactored the design of the system to the point that it is really easy to add new features and change old ones. The second release was done by the end of June and was taken to the trade show. It had less in it than Jane and Russ would have liked, but it did demonstrate the most important features of the system. Although customers at the trade show noticed that certain features were missing, they were very impressed overall. You, Russ, and Jane all returned from the trade show with smiles on your faces. You all felt as though this project was a winner.   Indeed, many months later, you are contacted by Rufus Inc. That company had been working on a system like this for its internal operations. Rufus has canceled the development of that system after a death-march project and is negotiating to license your technology for its environment.   Indeed, things are looking up!

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  • SQLAuthority News – TechEd India – April 12-14, 2010 Bangalore – An Unforgettable Experience – An Op

    - by pinaldave
    TechEd India was one of the largest Technology events in India led by Microsoft. This event was attended by more than 3,000 technology enthusiasts, making it one of the most well-organized events of the year. Though I attempted to attend almost all the technology events here, I have not seen any bigger or better event in Indian subcontinents other than this. There are 21 Technical Tracks at Tech·Ed India 2010 that span more than 745 learning opportunities. I was fortunate enough to be a part of this whole event as a speaker and a delegate, as well. TechEd India Speaker Badge and A Token of Lifetime Hotel Selection I presented three different sessions at TechEd India and was also a part of panel discussion. (The details of the sessions are given at the end of this blog post.) Due to extensive traveling, I stay away from my family occasionally. For this reason, I took my wife – Nupur and daughter Shaivi (8 months old) to the event along with me. We stayed at the same hotel where the event was organized so as to maximize my time bonding with my family and to have more time in networking with technology community, at the same time. The hotel Lalit Ashok is the largest and most luxurious venue one can find in Bangalore, located in the middle of the city. The cost of the hotel was a bit pricey, but looking at all the advantages, I had decided to ask for a booking there. Hotel Lalit Ashok Nupur Dave and Shaivi Dave Arrival Day – DAY 0 – April 11, 2010 I reached the event a day earlier, and that was one wise decision for I was able to relax a bit and go over my presentation for the next day’s course. I am a kind of person who likes to get everything ready ahead of time. I was also able to enjoy a pleasant evening with several Microsoft employees and my family friends. I even checked out the location where I would be doing presentations the next day. I was fortunate enough to meet Bijoy Singhal from Microsoft who helped me out with a few of the logistics issues that occured the day before. I was not aware of the fact that the very next day he was going to be “The Man” of the TechEd 2010 event. Vinod Kumar from Microsoft was really very kind as he talked to me regarding my subsequent session. He gave me some suggestions which were really helpful that I was able to incorporate them during my presentation. Finally, I was able to meet Abhishek Kant from Microsoft; his valuable suggestions and unlimited passion have inspired many people like me to work with the Community. Pradipta from Microsoft was also around, being extremely busy with logistics; however, in those busy times, he did find some good spare time to have a chat with me and the other Community leaders. I also met Harish Ranganathan and Sachin Rathi, both from Microsoft. It was so interesting to listen to both of them talking about SharePoint. I just have no words to express my overwhelmed spirit because of all these passionate young guys - Pradipta,Vinod, Bijoy, Harish, Sachin and Ahishek (of course!). Map of TechEd India 2010 Event Day 1 – April 12, 2010 From morning until night time, today was truly a very busy day for me. I had two presentations and one panel discussion for the day. Needless to say, I had a few meetings to attend as well. The day started with a keynote from S. Somaseger where he announced the launch of Visual Studio 2010. The keynote area was really eye-catching because of the very large, bigger-than- life uniform screen. This was truly one to show. The title music of the keynote was very interesting and it featured Bijoy Singhal as the model. It was interesting to talk to him afterwards, when we laughed at jokes together about his modeling assignment. TechEd India Keynote Opening Featuring Bijoy TechEd India 2010 Keynote – S. Somasegar Time: 11:15pm – 11:45pm Session 1: True Lies of SQL Server – SQL Myth Buster Following the excellent keynote, I had my very first session on the subject of SQL Server Myth Buster. At first, I was a bit nervous as right after the keynote, for this was my very first session and during my presentation I saw lots of Microsoft Product Team members. Well, it really went well and I had a really good discussion with attendees of the session. I felt that a well begin was half-done and my confidence was regained. Right after the session, I met a few of my Community friends and had meaningful discussions with them on many subjects. The abstract of the session is as follows: In this 30-minute demo session, I am going to briefly demonstrate few SQL Server Myths and their resolutions as I back them up with some demo. This demo presentation is a must-attend for all developers and administrators who would come to the event. This is going to be a very quick yet fun session. Pinal Presenting session at TechEd India 2010 Time: 1:00 PM – 2:00 PM Lunch with Somasegar After the session I went to see my daughter, and then I headed right away to the lunch with S. Somasegar – the keynote speaker and senior vice president of the Developer Division at Microsoft. I really thank to Abhishek who made it possible for us. Because of his efforts, all the MVPs had the opportunity to meet such a legendary person and had to talk with them on Microsoft Technology. Though Somasegar is currently holding such a high position in Microsoft, he is very polite and a real gentleman, and how I wish that everybody in industry is like him. Believe me, if you spread love and kindness, then that is what you will receive back. As soon as lunch time was over, I ran to the session hall as my second presentation was about to start. Time: 2:30pm – 3:30pm Session 2: Master Data Services in Microsoft SQL Server 2008 R2 Business Intelligence is a subject which was widely talked about at TechEd. Everybody was interested in this subject, and I did not excuse myself from this great concept as well. I consider myself fortunate as I was presenting on the subject of Master Data Services at TechEd. When I had initially learned this subject, I had a bit of confusion about the usage of this tool. Later on, I decided that I would tackle about how we all developers and DBAs are not able to understand something so simple such as this, and even worst, creating confusion about the technology. During system designing, it is very important to have a reference material or master lookup tables. Well, I talked about the same subject and presented the session keeping that as my center talk. The session went very well and I received lots of interesting questions. I got many compliments for talking about this subject on the real-life scenario. I really thank Rushabh Mehta (CEO, Solid Quality Mentors India) for his supportive suggestions that helped me prepare the slide deck, as well as the subject. Pinal Presenting session at TechEd India 2010 The abstract of the session is as follows: SQL Server Master Data Services will ship with SQL Server 2008 R2 and will improve Microsoft’s platform appeal. This session provides an in-depth demonstration of MDS features and highlights important usage scenarios. Master Data Services enables consistent decision-making process by allowing you to create, manage and propagate changes from a single master view of your business entities. Also, MDS – Master Data-hub which is a vital component, helps ensure the consistency of reporting across systems and deliver faster and more accurate results across the enterprise. We will talk about establishing the basis for a centralized approach to defining, deploying, and managing master data in the enterprise. Pinal Presenting session at TechEd India 2010 The day was still not over for me. I had ran into several friends but we were not able keep our enthusiasm under control about all the rumors saying that SQL Server 2008 R2 was about to be launched tomorrow in the keynote. I then ran to my third and final technical event for the day- a panel discussion with the top technologies of India. Time: 5:00pm – 6:00pm Panel Discussion: Harness the power of Web – SEO and Technical Blogging As I have delivered two technical sessions by this time, I was a bit tired but  not less enthusiastic when I had to talk about Blog and Technology. We discussed many different topics there. I told them that the most important aspect for any blog is its content. We discussed in depth the issues with plagiarism and how to avoid it. Another topic of discussion was how we technology bloggers can create awareness in the Community about what the right kind of blogging is and what morally and technically wrong acts are. A couple of questions were raised about what type of liberty a person can have in terms of writing blogs. Well, it was generically agreed that a blog is mainly a representation of our ideas and thoughts; it should not be governed by external entities. As long as one is writing what they really want to say, but not providing incorrect information or not practicing plagiarism, a blogger should be allowed to express himself. This panel discussion was supposed to be over in an hour, but the interest of the participants was remarkable and so it was extended for 30 minutes more. Finally, we decided to bring to a close the discussion and agreed that we will continue the topic next year. TechEd India Panel Discussion on Web, Technology and SEO Surprisingly, the day was just beginning after doing all of these. By this time, I have almost met all the MVP who arrived at the event, as well as many Microsoft employees. There were lots of Community folks present, too. I decided that I would go to meet several friends from the Community and continue to communicate with me on SQLAuthority.com. I also met Abhishek Baxi and had a good talk with him regarding Win Mobile and Twitter. He also took a very quick video of me wherein I spoke in my mother’s tongue, Gujarati. It was funny that I talked in Gujarati almost all the day, but when I was talking in the interview I could not find the right Gujarati words to speak. I think we all think in English when we think about Technology, so as to address universality. After meeting them, I headed towards the Speakers’ Dinner. Time: 8:00 PM – onwards Speakers Dinner The Speakers’ dinner was indeed a wonderful opportunity for all the speakers to get together and relax. We talked so many different things, from XBOX to Hindi Movies, and from SQL to Samosas. I just could not express how much fun I had. After a long evening, when I returned tmy room and met Shaivi, I just felt instantly relaxed. Kids are really gifts from God. Today was a really long but exciting day. So many things happened in just one day: Visual Studio Lanch, lunch with Somasegar, 2 technical sessions, 1 panel discussion, community leaders meeting, speakers dinner and, last but not leas,t playing with my child! A perfect day! Day 2 – April 13, 2010 Today started with a bang with the excellent keynote by Kamal Hathi who launched SQL Server 2008 R2 in India and demonstrated the power of PowerPivot to all of us. 101 Million Rows in Excel brought lots of applause from the audience. Kamal Hathi Presenting Keynote at TechEd India 2010 The day was a bit easier one for me. I had no sessions today and no events planned. I had a few meetings planned for the second day of the event. I sat in the speaker’s lounge for half a day and met many people there. I attended nearly 9 different meetings today. The subjects of the meetings were very different. Here is a list of the topics of the Community-related meetings: SQL PASS and its involvement in India and subcontinents How to start community blogging Forums and developing aptitude towards technology Ahmedabad/Gandhinagar User Groups and their developments SharePoint and SQL Business Meeting – a client meeting Business Meeting – a potential performance tuning project Business Meeting – Solid Quality Mentors (SolidQ) And family friends Pinal Dave at TechEd India The day passed by so quickly during this meeting. In the evening, I headed to Partners Expo with friends and checked out few of the booths. I really wanted to talk about some of the products, but due to the freebies there was so much crowd that I finally decided to just take the contact details of the partner. I will now start sending them with my queries and, hopefully, I will have my questions answered. Nupur and Shaivi had also one meeting to attend; it was with our family friend Vijay Raj. Vijay is also a person who loves Technology and loves it more than anybody. I see him growing and learning every day, but still remaining as a ‘human’. I believe that if someone acquires as much knowledge as him, that person will become either a computer or cyborg. Here, Vijay is still a kind gentleman and is able to stay as our close family friend. Shaivi was really happy to play with Uncle Vijay. Pinal Dave and Vijay Raj Renuka Prasad, a Microsoft MVP, impressed me with his passion and knowledge of SQL. Every time he gives me credit for his success, I believe that he is very humble. He has way more certifications than me and has worked many more years with SQL compared to me. He is an excellent photographer as well. Most of the photos in this blog post have been taken by him. I told him if ever he wants to do a part time job, he can do the photography very well. Pinal Dave and Renuka Prasad I also met L Srividya from Microsoft, whom I was looking forward to meet. She is a bundle of knowledge that everyone would surely learn a lot from her. I was able to get a few minutes from her and well, I felt confident. She enlightened me with SQL Server BI concepts, domain management and SQL Server security and few other interesting details. I also had a wonderful time talking about SharePoint with fellow Solid Quality Mentor Joy Rathnayake. He is very passionate about SharePoint but when you talk .NET and SQL with him, he is still overwhelmingly knowledgeable. In fact, while talking to him, I figured out that the recent training he delivered was on SQL Server 2008 R2. I told him a joke that it hurts my ego as he is more popular now in SQL training and consulting than me. I am sure all of you agree that working with good people is a gift from God. I am fortunate enough to work with the best of the best Industry experts. It was a great pleasure to hang out with my Community friends – Ahswin Kini, HimaBindu Vejella, Vasudev G, Suprotim Agrawal, Dhananjay, Vikram Pendse, Mahesh Dhola, Mahesh Mitkari,  Manu Zacharia, Shobhan, Hardik Shah, Ashish Mohta, Manan, Subodh Sohani and Sanjay Shetty (of course!) .  (Please let me know if I have met you at the event and forgot your name to list here). Time: 8:00 PM – onwards Community Leaders Dinner After lots of meetings, I headed towards the Community Leaders dinner meeting and met almost all the folks I met in morning. The discussion was almost the same but the real good thing was that we were enjoying it. The food was really good. Nupur was invited in the event, but Shaivi could not come. When Nupur tried to enter the event, she was stopped as Shaivi did not have the pass to enter the dinner. Nupur expressed that Shaivi is only 8 months old and does not eat outside food as well and could not stay by herself at this age, but the door keeper did not agree and asked that without the entry details Shaivi could not go in, but Nupur could. Nupur called me on phone and asked me to help her out. By the time, I was outside; the organizer of the event reached to the door and happily approved Shaivi to join the party. Once in the party, Shaivi had lots of fun meeting so many people. Shaivi Dave and Abhishek Kant Dean Guida (Infragistics President and CEO) and Pinal Dave (SQLAuthority.com) Day 3 – April 14, 2010 Though, it was last day, I was very much excited today as I was about to present my very favorite session. Query Optimization and Performance Tuning is my domain expertise and I make my leaving by consulting and training the same. Today’s session was on the same subject and as an additional twist, another subject about Spatial Database was presented. I was always intrigued with Spatial Database and I have enjoyed learning about it; however, I have never thought about Spatial Indexing before it was decided that I will do this session. I really thank Solid Quality Mentor Dr. Greg Low for his assistance in helping me prepare the slide deck and also review the content. Furthermore, today was really what I call my ‘learning day’ . So far I had not attended any session in TechEd and I felt a bit down for that. Everybody spends their valuable time & money to learn something new and exciting in TechEd and I had not attended a single session at the moment thinking that it was already last day of the event. I did have a plan for the day and I attended two technical sessions before my session of spatial database. I attended 2 sessions of Vinod Kumar. Vinod is a natural storyteller and there was no doubt that his sessions would be jam-packed. People attended his sessions simply because Vinod is syhe speaker. He did not have a single time disappointed audience; he is truly a good speaker. He knows his stuff very well. I personally do not think that in India he can be compared to anyone for SQL. Time: 12:30pm-1:30pm SQL Server Query Optimization, Execution and Debugging Query Performance I really had a fun time attending this session. Vinod made this session very interactive. The entire audience really got into the presentation and started participating in the event. Vinod was presenting a small problem with Query Tuning, which any developer would have encountered and solved with their help in such a fashion that a developer feels he or she have already resolved it. In one question, I was the only one who was ready to answer and Vinod told me in a light tone that I am now allowed to answer it! The audience really found it very amusing. There was a huge crowd around Vinod after the session. Vinod – A master storyteller! Time: 3:45pm-4:45pm Data Recovery / consistency with CheckDB This session was much heavier than the earlier one, and I must say this is my most favorite session I EVER attended in India. In this TechEd I have only attended two sessions, but in my career, I have attended numerous technical sessions not only in India, but all over the world. This session had taken my breath away. One by one, Vinod took the different databases, and started to corrupt them in different ways. Each database has some unique ways to get corrupted. Once that was done, Vinod started to show the DBCC CEHCKDB and demonstrated how it can solve your problem. He finally fixed all the databases with this single tool. I do have a good knowledge of this subject, but let me honestly admit that I have learned a lot from this session. I enjoyed and cheered during this session along with other attendees. I had total satisfaction that, just like everyone, I took advantage of the event and learned something. I am now TECHnically EDucated. Pinal Dave and Vinod Kumar After two very interactive and informative SQL Sessions from Vinod Kumar, the next turn me presenting on Spatial Database and Indexing. I got once again nervous but Vinod told me to stay natural and do my presentation. Well, once I got a huge stage with a total of four projectors and a large crowd, I felt better. Time: 5:00pm-6:00pm Session 3: Developing with SQL Server Spatial and Deep Dive into Spatial Indexing Pinal Presenting session at TechEd India 2010 Pinal Presenting session at TechEd India 2010 I kicked off this session with Michael J Swart‘s beautiful spatial image. This session was the last one for the day but, to my surprise, I had more than 200+ attendees. Slowly, the rain was starting outside and I was worried that the hall would not be full; despite this, there was not a single seat available in the first five minutes of the session. Thanks to all of you for attending my presentation. I had demonstrated the map of world (and India) and quickly explained what  Geographic and Geometry data types in Spatial Database are. This session had interesting story of Indexing and Comparison, as well as how different traditional indexes are from spatial indexing. Pinal Presenting session at TechEd India 2010 Due to the heavy rain during this event, the power went off for about 22 minutes (just an accident – nobodies fault). During these minutes, there were no audio, no video and no light. I continued to address the mass of 200+ people without any audio device and PowerPoint. I must thank the audience because not a single person left from the session. They all stayed in their place, some moved closure to listen to me properly. I noticed that the curiosity and eagerness to learn new things was at the peak even though it was the very last session of the TechEd. Everybody wanted get the maximum knowledge out of this whole event. I was touched by the support from audience. They listened and participated in my session even without any kinds of technology (no ppt, no mike, no AC, nothing). During these 22 minutes, I had completed my theory verbally. Pinal Presenting session at TechEd India 2010 After a while, we got the projector back online and we continued with some exciting demos. Many thanks to Microsoft people who worked energetically in background to get the backup power for project up. I had a very interesting demo wherein I overlaid Bangalore and Hyderabad on the India Map and find their aerial distance between them. After finding the aerial distance, we browsed online and found that SQL Server estimates the exact aerial distance between these two cities, as compared to the factual distance. There was a huge applause from the crowd on the subject that SQL Server takes into the count of the curvature of the earth and finds the precise distances based on details. During the process of finding the distance, I demonstrated a few examples of the indexes where I expressed how one can use those indexes to find these distances and how they can improve the performance of similar query. I also demonstrated few examples wherein we were able to see in which data type the Index is most useful. We finished the demos with a few more internal stuff. Pinal Presenting session at TechEd India 2010 Despite all issues, I was mostly satisfied with my presentation. I think it was the best session I have ever presented at any conference. There was no help from Technology for a while, but I still got lots of appreciation at the end. When we ended the session, the applause from the audience was so loud that for a moment, the rain was not audible. I was truly moved by the dedication of the Technology enthusiasts. Pinal Dave After Presenting session at TechEd India 2010 The abstract of the session is as follows: The Microsoft SQL Server 2008 delivers new spatial data types that enable you to consume, use, and extend location-based data through spatial-enabled applications. Attend this session to learn how to use spatial functionality in next version of SQL Server to build and optimize spatial queries. This session outlines the new geography data type to store geodetic spatial data and perform operations on it, use the new geometry data type to store planar spatial data and perform operations on it, take advantage of new spatial indexes for high performance queries, use the new spatial results tab to quickly and easily view spatial query results directly from within Management Studio, extend spatial data capabilities by building or integrating location-enabled applications through support for spatial standards and specifications and much more. Time: 8:00 PM – onwards Dinner by Sponsors After the lively session during the day, there was another dinner party courtesy of one of the sponsors of TechEd. All the MVPs and several Community leaders were present at the dinner. I would like to express my gratitude to Abhishek Kant for organizing this wonderful event for us. It was a blast and really relaxing in all angles. We all stayed there for a long time and talked about our sweet and unforgettable memories of the event. Pinal Dave and Bijoy Singhal It was really one wonderful event. After writing this much, I say that I have no words to express about how much I enjoyed TechEd. However, it is true that I shared with you only 1% of the total activities I have done at the event. There were so many people I have met, yet were not mentioned here although I wanted to write their names here, too . Anyway, I have learned so many things and up until now, I am not able to get over all the fun I had in this event. Pinal Dave at TechEd India 2010 The Next Days – April 15, 2010 – till today I am still not able to get my mind out of the whole experience I had at TechEd India 2010. It was like a whole Microsoft Family working together to celebrate a happy occasion. TechEd India – Truly An Unforgettable Experience! Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: About Me, MVP, Pinal Dave, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, SQLServer, T SQL, Technology Tagged: TechEd, TechEdIn

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  • URL Rewrite – Multiple domains under one site. Part II

    - by OWScott
    I believe I have it … I’ve been meaning to put together the ultimate outgoing rule for hosting multiple domains under one site.  I finally sat down this week and setup a few test cases, and created one rule to rule them all.  In Part I of this two part series, I covered the incoming rule necessary to host a site in a subfolder of a website, while making it appear as if it’s in the root of the site.  Part II won’t work without applying Part I first, so if you haven’t read it, I encourage you to read it now. However, the incoming rule by itself doesn’t address everything.  Here’s the problem … Let’s say that we host www.site2.com in a subfolder called site2, off of masterdomain.com.  This is the same example I used in Part I.   Using an incoming rewrite rule, we are able to make a request to www.site2.com even though the site is really in the /site2 folder.  The gotcha comes with any type of path that ASP.NET generates (I’m sure other scripting technologies could do the same too).  ASP.NET thinks that the path to the root of the site is /site2, but the URL is /.  See the issue?  If ASP.NET generates a path or a redirect for us, it will always add /site2 to the URL.  That results in a path that looks something like www.site2.com/site2.  In Part I, I mentioned that you should add a condition where “{PATH_INFO} ‘does not match’ /site2”.  That allows www.site2.com/site2 and www.site2.com to both function the same.  This allows the site to always work, but if you want to hide /site2 in the URL, you need to take it one step further. One way to address this is in your code.  Ultimately this is the best bet.  Ruslan Yakushev has a great article on a few considerations that you can address in code.  I recommend giving that serious consideration.  Additionally, if you have upgraded to ASP.NET 3.5 SP1 or greater, it takes care of some of the references automatically for you. However, what if you inherit an existing application?  Or you can’t easily go through your existing site and make the code changes?  If this applies to you, read on. That’s where URL Rewrite 2.0 comes in.  With URL Rewrite 2.0, you can create an outgoing rule that will remove the /site2 before the page is sent back to the user.  This means that you can take an existing application, host it in a subfolder of your site, and ensure that the URL never reveals that it’s in a subfolder. Performance Considerations Performance overhead is something to be mindful of.  These outbound rules aren’t simply changing the server variables.  The first rule I’ll cover below needs to parse the HTML body and pull out the path (i.e. /site2) on the way through.  This will add overhead, possibly significant if you have large pages and a busy site.  In other words, your mileage may vary and you may need to test to see the impact that these rules have.  Don’t worry too much though.  For many sites, the performance impact is negligible. So, how do we do it? Creating the Outgoing Rule There are really two things to keep in mind.  First, ASP.NET applications frequently generate a URL that adds the /site2 back into the URL.  In addition to URLs, they can be in form elements, img elements and the like.  The goal is to find all of those situations and rewrite it on the way out.  Let’s call this the ‘URL problem’. Second, and similarly, ASP.NET can send a LOCATION redirect that causes a redirect back to another page.  Again, ASP.NET isn’t aware of the different URL and it will add the /site2 to the redirect.  Form Authentication is a good example on when this occurs.  Try to password protect a site running from a subfolder using forms auth and you’ll quickly find that the URL becomes www.site2.com/site2 again.  Let’s term this the ‘redirect problem’. Solving the URL Problem – Outgoing Rule #1 Let’s create a rule that removes the /site2 from any URL.  We want to remove it from relative URLs like /site2/something, or absolute URLs like http://www.site2.com/site2/something.  Most URLs that ASP.NET creates will be relative URLs, but I figure that there may be some applications that piece together a full URL, so we might as well expect that situation. Let’s get started.  First, create a new outbound rule.  You can create the rule within the /site2 folder which will reduce the performance impact of the rule.  Just a reminder that incoming rules for this situation won’t work in a subfolder … but outgoing rules will. Give it a name that makes sense to you, for example “Outgoing – URL paths”. Precondition.  If you place the rule in the subfolder, it will only run for that site and folder, so there isn’t need for a precondition.  Run it for all requests.  If you place it in the root of the site, you may want to create a precondition for HTTP_HOST = ^(www\.)?site2\.com$. For the Match section, there are a few things to consider.  For performance reasons, it’s best to match the least amount of elements that you need to accomplish the task.  For my test cases, I just needed to rewrite the <a /> tag, but you may need to rewrite any number of HTML elements.  Note that as long as you have the exclude /site2 rule in your incoming rule as I described in Part I, some elements that don’t show their URL—like your images—will work without removing the /site2 from them.  That reduces the processing needed for this rule. Leave the “matching scope” at “Response” and choose the elements that you want to change. Set the pattern to “^(?:site2|(.*//[_a-zA-Z0-9-\.]*)?/site2)(.*)”.  Make sure to replace ‘site2’ with your subfolder name in both places.  Yes, I realize this is a pretty messy looking rule, but it handles a few situations.  This rule will handle the following situations correctly: Original Rewritten using {R:1}{R:2} http://www.site2.com/site2/default.aspx http://www.site2.com/default.aspx http://www.site2.com/folder1/site2/default.aspx Won’t rewrite since it’s a sub-sub folder /site2/default.aspx /default.aspx site2/default.aspx /default.aspx /folder1/site2/default.aspx Won’t rewrite since it’s a sub-sub folder. For the conditions section, you can leave that be. Finally, for the rule, set the Action Type to “Rewrite” and set the Value to “{R:1}{R:2}”.  The {R:1} and {R:2} are back references to the sections within parentheses.  In other words, in http://domain.com/site2/something, {R:1} will be http://domain.com and {R:2} will be /something. If you view your rule from your web.config file (or applicationHost.config if it’s a global rule), it should look like this: <rule name="Outgoing - URL paths" enabled="true"> <match filterByTags="A" pattern="^(?:site2|(.*//[_a-zA-Z0-9-\.]*)?/site2)(.*)" /> <action type="Rewrite" value="{R:1}{R:2}" /> </rule> Solving the Redirect Problem Outgoing Rule #2 The second issue that we can run into is with a client-side redirect.  This is triggered by a LOCATION response header that is sent to the client.  Forms authentication is a common example.  To reproduce this, password protect your subfolder and watch how it redirects and adds the subfolder path back in. Notice in my test case the extra paths: http://site2.com/site2/login.aspx?ReturnUrl=%2fsite2%2fdefault.aspx I want to remove /site2 from both the URL and the ReturnUrl querystring value.  For semi-readability, let’s do this in 2 separate rules, one for the URL and one for the querystring. Create a second rule.  As with the previous rule, it can be created in the /site2 subfolder.  In the URL Rewrite wizard, select Outbound rules –> “Blank Rule”. Fill in the following information: Name response_location URL Precondition Don’t set Match: Matching Scope Server Variable Match: Variable Name RESPONSE_LOCATION Match: Pattern ^(?:site2|(.*//[_a-zA-Z0-9-\.]*)?/site2)(.*) Conditions Don’t set Action Type Rewrite Action Properties {R:1}{R:2} It should end up like so: <rule name="response_location URL"> <match serverVariable="RESPONSE_LOCATION" pattern="^(?:site2|(.*//[_a-zA-Z0-9-\.]*)?/site2)(.*)" /> <action type="Rewrite" value="{R:1}{R:2}" /> </rule> Outgoing Rule #3 Outgoing Rule #2 only takes care of the URL path, and not the querystring path.  Let’s create one final rule to take care of the path in the querystring to ensure that ReturnUrl=%2fsite2%2fdefault.aspx gets rewritten to ReturnUrl=%2fdefault.aspx. The %2f is the HTML encoding for forward slash (/). Create a rule like the previous one, but with the following settings: Name response_location querystring Precondition Don’t set Match: Matching Scope Server Variable Match: Variable Name RESPONSE_LOCATION Match: Pattern (.*)%2fsite2(.*) Conditions Don’t set Action Type Rewrite Action Properties {R:1}{R:2} The config should look like this: <rule name="response_location querystring"> <match serverVariable="RESPONSE_LOCATION" pattern="(.*)%2fsite2(.*)" /> <action type="Rewrite" value="{R:1}{R:2}" /> </rule> It’s possible to squeeze the last two rules into one, but it gets kind of confusing so I felt that it’s better to show it as two separate rules. Summary With the rules covered in these two parts, we’re able to have a site in a subfolder and make it appear as if it’s in the root of the site.  Not only that, we can overcome automatic redirecting that is caused by ASP.NET, other scripting technologies, and especially existing applications. Following is an example of the incoming and outgoing rules necessary for a site called www.site2.com hosted in a subfolder called /site2.  Remember that the outgoing rules can be placed in the /site2 folder instead of the in the root of the site. <rewrite> <rules> <rule name="site2.com in a subfolder" enabled="true" stopProcessing="true"> <match url=".*" /> <conditions logicalGrouping="MatchAll" trackAllCaptures="false"> <add input="{HTTP_HOST}" pattern="^(www\.)?site2\.com$" /> <add input="{PATH_INFO}" pattern="^/site2($|/)" negate="true" /> </conditions> <action type="Rewrite" url="/site2/{R:0}" /> </rule> </rules> <outboundRules> <rule name="Outgoing - URL paths" enabled="true"> <match filterByTags="A" pattern="^(?:site2|(.*//[_a-zA-Z0-9-\.]*)?/site2)(.*)" /> <action type="Rewrite" value="{R:1}{R:2}" /> </rule> <rule name="response_location URL"> <match serverVariable="RESPONSE_LOCATION" pattern="^(?:site2|(.*//[_a-zA-Z0-9-\.]*)?/site2)(.*)" /> <action type="Rewrite" value="{R:1}{R:2}" /> </rule> <rule name="response_location querystring"> <match serverVariable="RESPONSE_LOCATION" pattern="(.*)%2fsite2(.*)" /> <action type="Rewrite" value="{R:1}{R:2}" /> </rule> </outboundRules> </rewrite> If you run into any situations that aren’t caught by these rules, please let me know so I can update this to be as complete as possible. Happy URL Rewriting!

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  • Chicago SQL Saturday

    - by Johnm
    This past Saturday, April 17, 2010, I journeyed North to the great city of Chicago for some SQL Server fun, learning and fellowship. The Chicago edition of this grassroots phenomenon was the 31st scheduled SQL Saturday since the program's birth in late 2007. The Chicago SQL Saturday consisted of four tracks with eight sessions each and was a very energetic and fast paced day for the 300+/- SQL Server enthusiasts in attendance. The speaker line up included national notables such as Kevin Kline, Brent Ozar, and Brad McGehee. My hometown of Indianapolis was well represented in the speaker line up with Arie Jones, Aaron King and Derek Comingore. The day began with a very humorous keynote by Kevin Kline and Brent Ozar who emphasized the importance of community events such as SQL Saturday and the monthly user group meetings. They also brilliantly included the impact that getting involved in the SQL community through social media can have on your professional career. My approach to the day was to try to experience as much of the event as I could, so there were very few sessions that I attended for their full duration. I leaped from session to session like a bumble bee, gleaning bits of nectar from each session. Amid these leaps I took the opportunity to briefly chat with some of the in-the-queue speakers as well as other attendees that wondered the hallways. I especially enjoyed a great discussion with Devin Knight about his plans regarding the upcoming Jacksonville SQL Saturday as well as an interesting SQL interpretation of the Iron Chef, which I think would catch on like wild-fire. There were two sessions that stood out as exceptional. So much so that I could not pull myself away: Kevin Kline presented on "SQL Server Internals and Architecture". This session could have been classified as one that is intended for the beginner. Kevin even personally warned me of such as I entered the room. I am a believer in revisiting the basics regardless of the level of your mastery, so I entered into this session in that spirit. It was a very clear and precise presentation. Masterfully illustrated and demonstrated. Brad McGehee presented on "How and When to Use Indexed Views". This was a topic that I was recently exploring and was considering to for use in an integration project. Brad effectively communicated the complexity of this feature and what is involved to gain their full benefit. It was clear at the conclusion of this session that it was not the right feature for my specific needs. Overall, the event was a great success. The use of volunteers, from an attendee's perspective was masterful. The only recommendation that I would have for the next Chicago SQL Saturday would be to include more time in between sessions to permit some level of networking among the attendees, one-on-one questions for speakers and visits to the sponsor booths. Congratulations to Wendy Pastrick, Ted Krueger, and Aaron Lowe for their efforts and a very successful SQL Saturday!

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  • Load and Web Performance Testing using Visual Studio Ultimate 2010-Part 3

    - by Tarun Arora
    Welcome back once again, in Part 1 of Load and Web Performance Testing using Visual Studio 2010 I talked about why Performance Testing the application is important, the test tools available in Visual Studio Ultimate 2010 and various test rig topologies, in Part 2 of Load and Web Performance Testing using Visual Studio 2010 I discussed the details of web performance & load tests as well as why it’s important to follow a goal based pattern while performance testing your application. In part 3 I’ll be discussing Test Result Analysis, Test Result Drill through, Test Report Generation, Test Run Comparison, Asp.net Profiler and some closing thoughts. Test Results – I see some creepy worms! In Part 2 we put together a web performance test and a load test, lets run the test to see load test to see how the Web site responds to the load simulation. While the load test is running you will be able to see close to real time analysis in the Load Test Analyser window. You can use the Load Test Analyser to conduct load test analysis in three ways: Monitor a running load test - A condensed set of the performance counter data is maintained in memory. To prevent the results memory requirements from growing unbounded, up to 200 samples for each performance counter are maintained. This includes 100 evenly spaced samples that span the current elapsed time of the run and the most recent 100 samples.         After the load test run is completed - The test controller spools all collected performance counter data to a database while the test is running. Additional data, such as timing details and error details, is loaded into the database when the test completes. The performance data for a completed test is loaded from the database and analysed by the Load Test Analyser. Below you can see a screen shot of the summary view, this provides key results in a format that is compact and easy to read. You can also print the load test summary, this is generated after the test has completed or been stopped.         Analyse the load test results of a previously run load test – We’ll see this in the section where i discuss comparison between two test runs. The performance counters can be plotted on the graphs. You also have the option to highlight a selected part of the test and view details, drill down to the user activity chart where you can hover over to see more details of the test run.   Generate Report => Test Run Comparisons The level of reports you can generate using the Load Test Analyser is astonishing. You have the option to create excel reports and conduct side by side analysis of two test results or to track trend analysis. The tools also allows you to export the graph data either to MS Excel or to a CSV file. You can view the ASP.NET profiler report to conduct further analysis as well. View Data and Diagnostic Attachments opens the Choose Diagnostic Data Adapter Attachment dialog box to select an adapter to analyse the result type. For example, you can select an IntelliTrace adapter, click OK and open the IntelliTrace summary for the test agent that was used in the load test.   Compare results This creates a set of reports that compares the data from two load test results using tables and bar charts. I have taken these screen shots from the MSDN documentation, I would highly recommend exploring the wealth of knowledge available on MSDN. Leaving Thoughts While load testing the application with an excessive load for a longer duration of time, i managed to bring the IIS to its knees by piling up a huge queue of requests waiting to be processed. This clearly means that the IIS had run out of threads as all the threads were busy processing existing request, one easy way of fixing this is by increasing the default number of allocated threads, but this might escalate the problem. The better suggestion is to try and drill down to the actual root cause of the problem. When ever the garbage collection runs it stops processing any pages so all requests that come in during that period are queued up, but realistically the garbage collection completes in fraction of a a second. To understand this better lets look at the .net heap, it is divided into large heap and small heap, anything greater than 85kB in size will be allocated to the Large object heap, the Large object heap is non compacting and remember large objects are expensive to move around, so if you are allocating something in the large object heap, make sure that you really need it! The small object heap on the other hand is divided into generations, so all objects that are supposed to be short-lived are suppose to live in Gen-0 and the long living objects eventually move to Gen-2 as garbage collection goes through.  As you can see in the picture below all < 85 KB size objects are first assigned to Gen-0, when Gen-0 fills up and a new object comes in and finds Gen-0 full, the garbage collection process is started, the process checks for all the dead objects and assigns them as the valid candidate for deletion to free up memory and promotes all the remaining objects in Gen-0 to Gen-1. So in the future when ever you clean up Gen-1 you have to clean up Gen-0 as well. When you fill up Gen – 0 again, all of Gen – 1 dead objects are drenched and rest are moved to Gen-2 and Gen-0 objects are moved to Gen-1 to free up Gen-0, but by this time your Garbage collection process has started to take much more time than it usually takes. Now as I mentioned earlier when garbage collection is being run all page requests that come in during that period are queued up. Does this explain why possibly page requests are getting queued up, apart from this it could also be the case that you are waiting for a long running database process to complete.      Lets explore the heap a bit more… What is really a case of crisis is when the objects are living long enough to make it to Gen-2 and then dying, this is definitely a high cost operation. But sometimes you need objects in memory, for example when you cache data you hold on to the objects because you need to use them right across the user session, which is acceptable. But if you wanted to see what extreme caching can do to your server then write a simple application that chucks in a lot of data in cache, run a load test over it for about 10-15 minutes, forcing a lot of data in memory causing the heap to run out of memory. If you get to such a state where you start running out of memory the IIS as a mode of recovery restarts the worker process. It is great way to free up all your memory in the heap but this would clear the cache. The problem with this is if the customer had 10 items in their shopping basket and that data was stored in the application cache, the user basket will now be empty forcing them either to get frustrated and go to a competitor website or if the customer is really patient, give it another try! How can you address this, well two ways of addressing this; 1. Workaround – A x86 bit processor only allows a maximum of 4GB of RAM, this means the machine effectively has around 3.4 GB of RAM available, the OS needs about 1.5 GB of RAM to run efficiently, the IIS and .net framework also need their share of memory, leaving you a heap of around 800 MB to play with. Because Team builds by default build your application in ‘Compile as any mode’ it means the application is build such that it will run in x86 bit mode if run on a x86 bit processor and run in a x64 bit mode if run on a x64 but processor. The problem with this is not all applications are really x64 bit compatible specially if you are using com objects or external libraries. So, as a quick win if you compiled your application in x86 bit mode by changing the compile as any selection to compile as x86 in the team build, you will be able to run your application on a x64 bit machine in x86 bit mode (WOW – By running Windows on Windows) and what that means is, you could use 8GB+ worth of RAM, if you take away everything else your application will roughly get a heap size of at least 4 GB to play with, which is immense. If you need a heap size of more than 4 GB you have either build a software for NASA or there is something fundamentally wrong in your application. 2. Solution – Now that you have put a workaround in place the IIS will not restart the worker process that regularly, which means you can take a breather and start working to get to the root cause of this memory leak. But this begs a question “How do I Identify possible memory leaks in my application?” Well i won’t say that there is one single tool that can tell you where the memory leak is, but trust me, ‘Performance Profiling’ is a great start point, it definitely gets you started in the right direction, let’s have a look at how. Performance Wizard - Start the Performance Wizard and select Instrumentation, this lets you measure function call counts and timings. Before running the performance session right click the performance session settings and chose properties from the context menu to bring up the Performance session properties page and as shown in the screen shot below, check the check boxes in the group ‘.NET memory profiling collection’ namely ‘Collect .NET object allocation information’ and ‘Also collect the .NET Object lifetime information’.    Now if you fire off the profiling session on your pages you will notice that the results allows you to view ‘Object Lifetime’ which shows you the number of objects that made it to Gen-0, Gen-1, Gen-2, Large heap, etc. Another great feature about the profile is that if your application has > 5% cases where objects die right after making to the Gen-2 storage a threshold alert is generated to alert you. Since you have the option to also view the most expensive methods and by capturing the IntelliTrace data you can drill in to narrow down to the line of code that is the root cause of the problem. Well now that we have seen how crucial memory management is and how easy Visual Studio Ultimate 2010 makes it for us to identify and reproduce the problem with the best of breed tools in the product. Caching One of the main ways to improve performance is Caching. Which basically means you tell the web server that instead of going to the database for each request you keep the data in the webserver and when the user asks for it you serve it from the webserver itself. BUT that can have consequences! Let’s look at some code, trust me caching code is not very intuitive, I define a cache key for almost all searches made through the common search page and cache the results. The approach works fine, first time i get the data from the database and second time data is served from the cache, significant performance improvement, EXCEPT when two users try to do the same operation and run into each other. But it is easy to handle this by adding the lock as you can see in the snippet below. So, as long as a user comes in and finds that the cache is empty, the user locks and starts to get the cache no more concurrency issues. But lets say you are processing 10 requests per second, by the time i have locked the operation to get the results from the database, 9 other users came in and found that the cache key is null so after i have come out and populated the cache they will still go in to get the results again. The application will still be faster because the next set of 10 users and so on would continue to get data from the cache. BUT if we added another null check after locking to build the cache and before actual call to the db then the 9 users who follow me would not make the extra trip to the database at all and that would really increase the performance, but didn’t i say that the code won’t be very intuitive, may be you should leave a comment you don’t want another developer to come in and think what a fresher why is he checking for the cache key null twice !!! The downside of caching is, you are storing the data outside of the database and the data could be wrong because the updates applied to the database would make the data cached at the web server out of sync. So, how do you invalidate the cache? Well if you only had one way of updating the data lets say only one entry point to the data update you can write some logic to say that every time new data is entered set the cache object to null. But this approach will not work as soon as you have several ways of feeding data to the system or your system is scaled out across a farm of web servers. The perfect solution to this is Micro Caching which means you cache the query for a set time duration and invalidate the cache after that set duration. The advantage is every time the user queries for that data with in the time span for which you have cached the results there are no calls made to the database and the data is served right from the server which makes the response immensely quick. Now figuring out the appropriate time span for which you micro cache the query results really depends on the application. Lets say your website gets 10 requests per second, if you retain the cache results for even 1 minute you will have immense performance gains. You would reduce 90% hits to the database for searching. Ever wondered why when you go to e-bookers.com or xpedia.com or yatra.com to book a flight and you click on the book button because the fare seems too exciting and you get an error message telling you that the fare is not valid any more. Yes, exactly => That is a cache failure! These travel sites or price compare engines are not going to hit the database every time you hit the compare button instead the results will be served from the cache, because the query results are micro cached, its a perfect trade-off, by micro caching the results the site gains 100% performance benefits but every once in a while annoys a customer because the fare has expired. But the trade off works in the favour of these sites as they are still able to process up to 30+ page requests per second which means cater to the site traffic by may be losing 1 customer every once in a while to a competitor who is also using a similar caching technique what are the odds that the user will not come back to their site sooner or later? Recap   Resources Below are some Key resource you might like to review. I would highly recommend the documentation, walkthroughs and videos available on MSDN. You can always make use of Fiddler to debug Web Performance Tests. Some community test extensions and plug ins available on Codeplex might also be of interest to you. The Road Ahead Thank you for taking the time out and reading this blog post, you may also want to read Part I and Part II if you haven’t so far. If you enjoyed the post, remember to subscribe to http://feeds.feedburner.com/TarunArora. Questions/Feedback/Suggestions, etc please leave a comment. Next ‘Load Testing in the cloud’, I’ll be working on exploring the possibilities of running Test controller/Agents in the Cloud. See you on the other side! Thank You!   Share this post : CodeProject

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  • The Windows Store... why did I sign up with this mess again?

    - by FransBouma
    Yesterday, Microsoft revealed that the Windows Store is now open to all developers in a wide range of countries and locations. For the people who think "wtf is the 'Windows Store'?", it's the central place where Windows 8 users will be able to find, download and purchase applications (or as we now have to say to not look like a computer illiterate: <accent style="Kentucky">aaaaappss</accent>) for Windows 8. As this is the store which is integrated into Windows 8, it's an interesting place for ISVs, as potential customers might very well look there first. This of course isn't true for all kinds of software, and developer tools in general aren't the kind of applications most users will download from the Windows store, but a presence there can't hurt. Now, this Windows Store hosts two kinds of applications: 'Metro-style' applications and 'Desktop' applications. The 'Metro-style' applications are applications created for the new 'Metro' UI which is present on Windows 8 desktop and Windows RT (the single color/big font fingerpaint-oriented UI). 'Desktop' applications are the applications we all run and use on Windows today. Our software are desktop applications. The Windows Store hosts all Metro-style applications locally in the store and handles the payment for these applications. This means you upload your application (sorry, 'app') to the store, jump through a lot of hoops, Microsoft verifies that your application is not violating a tremendous long list of rules and after everything is OK, it's published and hopefully you get customers and thus earn money. Money which Microsoft will pay you on a regular basis after customers buy your application. Desktop applications are not following this path however. Desktop applications aren't hosted by the Windows Store. Instead, the Windows Store more or less hosts a page with the application's information and where to get the goods. I.o.w.: it's nothing more than a product's Facebook page. Microsoft will simply redirect a visitor of the Windows Store to your website and the visitor will then use your site's system to purchase and download the application. This last bit of information is very important. So, this morning I started with fresh energy to register our company 'Solutions Design bv' at the Windows Store and our two applications, LLBLGen Pro and ORM Profiler. First I went to the Windows Store dashboard page. If you don't have an account, you have to log in or sign up if you don't have a live account. I signed in with my live account. After that, it greeted me with a page where I had to fill in a code which was mailed to me. My local mail server polls every several minutes for email so I had to kick it to get it immediately. I grabbed the code from the email and I was presented with a multi-step process to register myself as a company or as an individual. In red I was warned that this choice was permanent and not changeable. I chuckled: Microsoft apparently stores its data on paper, not in digital form. I chose 'company' and was presented with a lengthy form to fill out. On the form there were two strange remarks: Per company there can just be 1 (one, uno, not zero, not two or more) registered developer, and only that developer is able to upload stuff to the store. I have no idea how this works with large companies, oh the overhead nightmares... "Sorry, but John, our registered developer with the Windows Store is on holiday for 3 months, backpacking through Australia, no, he's not reachable at this point. M'yeah, sorry bud. Hey, did you fill in those TPS reports yesterday?" A separate Approver has to be specified, which has to be a different person than the registered developer. Apparently to Microsoft a company with just 1 person is not a company. Luckily we're with two people! *pfew*, dodged that one, otherwise I would be stuck forever: the choice I already made was not reversible! After I had filled out the form and it was all well and good and accepted by the Microsoft lackey who had to write it all down in some paper notebook ("Hey, be warned! It's a permanent choice! Written down in ink, can't be changed!"), I was presented with the question how I wanted to pay for all this. "Pay for what?" I wondered. Must be the paper they were scribbling the information on, I concluded. After all, there's a financial crisis going on! How could I forget! Silly me. "Ok fair enough". The price was 75 Euros, not the end of the world. I could only pay by credit card, so it was accepted quickly. Or so I thought. You see, Microsoft has a different idea about CC payments. In the normal world, you type in your CC number, some date, a name and a security code and that's it. But Microsoft wants to verify this even more. They want to make a verification purchase of a very small amount and are doing that with a special code in the description. You then have to type in that code in a special form in the Windows Store dashboard and after that you're verified. Of course they'll refund the small amount they pull from your card. Sounds simple, right? Well... no. The problem starts with the fact that I can't see the CC activity on some website: I have a bank issued CC card. I get the CC activity once a month on a piece of paper sent to me. The bank's online website doesn't show them. So it's possible I have to wait for this code till October 12th. One month. "So what, I'm not going to use it anyway, Desktop applications don't use the payment system", I thought. "Haha, you're so naive, dear developer!" Microsoft won't allow you to publish any applications till this verification is done. So no application publishing for a month. Wouldn't it be nice if things were, you know, digital, so things got done instantly? But of course, that lackey who scribbled everything in the Big Windows Store Registration Book isn't that quick. Can't blame him though. He's just doing his job. Now, after the payment was done, I was presented with a page which tells me Microsoft is going to use a third party company called 'Symantec', which will verify my identity again. The page explains to me that this could be done through email or phone and that they'll contact the Approver to verify my identity. "Phone?", I thought... that's a little drastic for a developer account to publish a single page of information about an external hosted software product, isn't it? On Facebook I just added a page, done. And paying you, Microsoft, took less information: you were happy to take my money before my identity was even 'verified' by this 3rd party's minions! "Double standards!", I roared. No-one cared. But it's the thought of getting it off your chest, you know. Luckily for me, everyone at Symantec was asleep when I was registering so they went for the fallback option in case phone calls were not possible: my Approver received an email. Imagine you have to explain the idiot web of security theater I was caught in to someone else who then has to reply a random person over the internet that I indeed was who I said I was. As she's a true sweetheart, she gave me the benefit of the doubt and assured that for now, I was who I said I was. Remember, this is for a desktop application, which is only a link to a website, some pictures and a piece of text. No file hosting, no payment processing, nothing, just a single page. Yeah, I also thought I was crazy. But we're not at the end of this quest yet. I clicked around in the confusing menus of the Windows Store dashboard and found the 'Desktop' section. I get a helpful screen with a warning in red that it can't find any certified 'apps'. True, I'm just getting started, buddy. I see a link: "Check the Windows apps you submitted for certification". Well, I haven't submitted anything, but let's see where it brings me. Oh the thrill of adventure! I click the link and I end up on this site: the hardware/desktop dashboard account registration. "Erm... but I just registered...", I mumbled to no-one in particular. Apparently for desktop registration / verification I have to register again, it tells me. But not only that, the desktop application has to be signed with a certificate. And not just some random el-cheapo certificate you can get at any mall's discount store. No, this certificate is special. It's precious. This certificate, the 'Microsoft Authenticode' Digital Certificate, is the only certificate that's acceptable, and jolly, it can be purchased from VeriSign for the price of only ... $99.-, but be quick, because this is a limited time offer! After that it's, I kid you not, $499.-. 500 dollars for a certificate to sign an executable. But, I do feel special, I got a special price. Only for me! I'm glowing. Not for long though. Here I started to wonder, what the benefit of it all was. I now again had to pay money for a shiny certificate which will add 'Solutions Design bv' to our installer as the publisher instead of 'unknown', while our customers download the file from our website. Not only that, but this was all about a Desktop application, which wasn't hosted by Microsoft. They only link to it. And make no mistake. These prices aren't single payments. Every year these have to be renewed. Like a membership of an exclusive club: you're special and privileged, but only if you cough up the dough. To give you an example how silly this all is: I added LLBLGen Pro and ORM Profiler to the Visual Studio Gallery some time ago. It's the same thing: it's a central place where one can find software which adds to / extends / works with Visual Studio. I could simply create the pages, add the information and they show up inside Visual Studio. No files are hosted at Microsoft, they're downloaded from our website. Exactly the same system. As I have to wait for the CC transcripts to arrive anyway, I can't proceed with publishing in this new shiny store. After the verification is complete I have to wait for verification of my software by Microsoft. Even Desktop applications need to be verified using a long list of rules which are mainly focused on Metro-style applications. Even while they're not hosted by Microsoft. I wonder what they'll find. "Your application wasn't approved. It violates rule 14 X sub D: it provides more value than our own competing framework". While I was writing this post, I tried to check something in the Windows Store Dashboard, to see whether I remembered it correctly. I was presented again with the question, after logging in with my live account, to enter the code that was just mailed to me. Not the previous code, a brand new one. Again I had to kick my mail server to pull the email to proceed. This was it. This 'experience' is so beyond miserable, I'm afraid I have to say goodbye for now to the 'Windows Store'. It's simply not worth my time. Now, about live accounts. You might know this: live accounts are tied to everything you do with Microsoft. So if you have an MSDN subscription, e.g. the one which costs over $5000.-, it's tied to this same live account. But the fun thing is, you can login with your live account to the MSDN subscriptions with just the account id and password. No additional code is mailed to you. While it gives you access to all Microsoft software available, including your licenses. Why the draconian security theater with this Windows Store, while all I want is to publish some desktop applications while on other Microsoft sites it's OK to simply sign in with your live account: no codes needed, no verification and no certificates? Microsoft, one thing you need with this store and that's: apps. Apps, apps, apps, apps, aaaaaaaaapps. Sorry, my bad, got carried away. I just can't stand the word 'app'. This store's shelves have to be filled to the brim with goods. But instead of being welcomed into the store with open arms, I have to fight an uphill battle with an endless list of rules and bullshit to earn the privilege to publish in this shiny store. As if I have to be thrilled to be one of the exclusive club called 'Windows Store Publishers'. As if Microsoft doesn't want it to succeed. Craig Stuntz sent me a link to an old blog post of his regarding code signing and uploading to Microsoft's old mobile store from back in the WinMo5 days: http://blogs.teamb.com/craigstuntz/2006/10/11/28357/. Good read and good background info about how little things changed over the years. I hope this helps Microsoft make things more clearer and smoother and also helps ISVs with their decision whether to go with the Windows Store scheme or ignore it. For now, I don't see the advantage of publishing there, especially not with the nonsense rules Microsoft cooked up. Perhaps it changes in the future, who knows.

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  • CLSF & CLK 2013 Trip Report by Jeff Liu

    - by jamesmorris
    This is a contributed post from Jeff Liu, lead XFS developer for the Oracle mainline Linux kernel team. Recently, I attended both the China Linux Storage and Filesystem workshop (CLSF), and the China Linux Kernel conference (CLK), which were held in Shanghai. Here are the highlights for both events. CLSF - 17th October XFS update (led by Jeff Liu) XFS keeps rapid progress with a lot of changes, especially focused on the infrastructure/performance improvements as well as  new feature development.  This can be reflected with a sample statistics among XFS/Ext4+JBD2/Btrfs via: # git diff --stat --minimal -C -M v3.7..v3.12-rc4 -- fs/xfs|fs/ext4+fs/jbd2|fs/btrfs XFS: 141 files changed, 27598 insertions(+), 19113 deletions(-) Ext4+JBD2: 39 files changed, 10487 insertions(+), 5454 deletions(-) Btrfs: 70 files changed, 19875 insertions(+), 8130 deletions(-) What made up those changes in XFS? Self-describing metadata(CRC32c). This is a new feature and it contributed about 70% code changes, it can be enabled via `mkfs.xfs -m crc=1 /dev/xxx` for v5 superblock. Transaction log space reservation improvements. With this change, we can calculate the log space reservation at mount time rather than runtime to reduce the the CPU overhead. User namespace support. So both XFS and USERNS can be enabled on kernel configuration begin from Linux 3.10. Thanks Dwight Engen's efforts for this thing. Split project/group quota inodes. Originally, project quota can not be enabled with group quota at the same time because they were share the same quota file inode, now it works but only for v5 super block. i.e, CRC enabled. CONFIG_XFS_WARN, an new lightweight runtime debugger which can be deployed in production environment. Readahead log object recovery, this change can speed up the log replay progress significantly. Speculative preallocation inode tracking, clearing and throttling. The main purpose is to deal with inodes with post-EOF space due to speculative preallocation, support improved quota management to free up a significant amount of unwritten space when at or near EDQUOT. It support backgroup scanning which occurs on a longish interval(5 mins by default, tunable), and on-demand scanning/trimming via ioctl(2). Bitter arguments ensued from this session, especially for the comparison between Ext4 and Btrfs in different areas, I have to spent a whole morning of the 1st day answering those questions. We basically agreed on XFS is the best choice in Linux nowadays because: Stable, XFS has a good record in stability in the past 10 years. Fengguang Wu who lead the 0-day kernel test project also said that he has observed less error than other filesystems in the past 1+ years, I own it to the XFS upstream code reviewer, they always performing serious code review as well as testing. Good performance for large/small files, XFS does not works very well for small files has already been an old story for years. Best choice (maybe) for distributed PB filesystems. e.g, Ceph recommends delopy OSD daemon on XFS because Ext4 has limited xattr size. Best choice for large storage (>16TB). Ext4 does not support a single file more than around 15.95TB. Scalability, any objection to XFS is best in this point? :) XFS is better to deal with transaction concurrency than Ext4, why? The maximum size of the log in XFS is 2038MB compare to 128MB in Ext4. Misc. Ext4 is widely used and it has been proved fast/stable in various loads and scenarios, XFS just need more customers, and Btrfs is still on the road to be a manhood. Ceph Introduction (Led by Li Wang) This a hot topic.  Li gave us a nice introduction about the design as well as their current works. Actually, Ceph client has been included in Linux kernel since 2.6.34 and supported by Openstack since Folsom but it seems that it has not yet been widely deployment in production environment. Their major work is focus on the inline data support to separate the metadata and data storage, reduce the file access time, i.e, a file access need communication twice, fetch the metadata from MDS and then get data from OSD, and also, the small file access is limited by the network latency. The solution is, for the small files they would like to store the data at metadata so that when accessing a small file, the metadata server can push both metadata and data to the client at the same time. In this way, they can reduce the overhead of calculating the data offset and save the communication to OSD. For this feature, they have only run some small scale testing but really saw noticeable improvements. Test environment: Intel 2 CPU 12 Core, 64GB RAM, Ubuntu 12.04, Ceph 0.56.6 with 200GB SATA disk, 15 OSD, 1 MDS, 1 MON. The sequence read performance for 1K size files improved about 50%. I have asked Li and Zheng Yan (the core developer of Ceph, who also worked on Btrfs) whether Ceph is really stable and can be deployed at production environment for large scale PB level storage, but they can not give a positive answer, looks Ceph even does not spread over Dreamhost (subject to confirmation). From Li, they only deployed Ceph for a small scale storage(32 nodes) although they'd like to try 6000 nodes in the future. Improve Linux swap for Flash storage (led by Shaohua Li) Because of high density, low power and low price, flash storage (SSD) is a good candidate to partially replace DRAM. A quick answer for this is using SSD as swap. But Linux swap is designed for slow hard disk storage, so there are a lot of challenges to efficiently use SSD for swap. SWAPOUT swap_map scan swap_map is the in-memory data structure to track swap disk usage, but it is a slow linear scan. It will become a bottleneck while finding many adjacent pages in the use of SSD. Shaohua Li have changed it to a cluster(128K) list, resulting in O(1) algorithm. However, this apporoach needs restrictive cluster alignment and only enabled for SSD. IO pattern In most cases, the swap io is in interleaved pattern because of mutiple reclaimers or a free cluster is shared by all reclaimers. Even though block layer can merge interleaved IO to some extent, but we cannot count on it completely. Hence the per-cpu cluster is added base on the previous change, it can help reclaimer do sequential IO and the block layer will be easier to merge IO. TLB flush: If we're reclaiming one active page, we should first move the page from active lru list to inactive lru list, and then reclaim the page from inactive lru to swap it out. During the process, we need to clear PTE twice: first is 'A'(ACCESS) bit, second is 'P'(PRESENT) bit. Processors need to send lots of ipi which make the TLB flush really expensive. Some works have been done to improve this, including rework smp_call_functiom_many() or remove the first TLB flush in x86, but there still have some arguments here and only parts of works have been pushed to mainline. SWAPIN: Page fault does iodepth=1 sync io, but it's a little waste if only issue a page size's IO. The obvious solution is doing swap readahead. But the current in-kernel swap readahead is arbitary(always 8 pages), and it always doesn't perform well for both random and sequential access workload. Shaohua introduced a new flag for madvise(MADV_WILLNEED) to do swap prefetch, so the changes happen in userspace API and leave the in-kernel readahead unchanged(but I think some improvement can also be done here). SWAP discard As we know, discard is important for SSD write throughout, but the current swap discard implementation is synchronous. He changed it to async discard which allow discard and write run in the same time. Meanwhile, the unit of discard is also optimized to cluster. Misc: lock contention For many concurrent swapout and swapin , the lock contention such as anon_vma or swap_lock is high, so he changed the swap_lock to a per-swap lock. But there still have some lock contention in very high speed SSD because of swapcache address_space lock. Zproject (led by Bob Liu) Bob gave us a very nice introduction about the current memory compression status. Now there are 3 projects(zswap/zram/zcache) which all aim at smooth swap IO storm and promote performance, but they all have their own pros and cons. ZSWAP It is implemented based on frontswap API and it uses a dynamic allocater named Zbud to allocate free pages. Zbud means pairs of zpages are "buddied" and it can only store at most two compressed pages in one page frame, so the max compress ratio is 50%. Each page frame is lru-linked and can do shink in memory pressure. If the compressed memory pool reach its limitation, shink or reclaim happens. It decompress the page frame into two new allocated pages and then write them to real swap device, but it can fail when allocating the two pages. ZRAM Acts as a compressed ramdisk and used as swap device, and it use zsmalloc as its allocator which has high density but may have fragmentation issues. Besides, page reclaim is hard since it will need more pages to uncompress and free just one page. ZRAM is preferred by embedded system which may not have any real swap device. Now both ZRAM and ZSWAP are in driver/staging tree, and in the mm community there are some disscussions of merging ZRAM into ZSWAP or viceversa, but no agreement yet. ZCACHE Handles file page compression but it is removed out of staging recently. From industry (led by Tang Jie, LSI) An LSI engineer introduced several new produces to us. The first is raid5/6 cards that it use full stripe writes to improve performance. The 2nd one he introduced is SandForce flash controller, who can understand data file types (data entropy) to reduce write amplification (WA) for nearly all writes. It's called DuraWrite and typical WA is 0.5. What's more, if enable its Dynamic Logical Capacity function module, the controller can do data compression which is transparent to upper layer. LSI testing shows that with this virtual capacity enables 1x TB drive can support up to 2x TB capacity, but the application must monitor free flash space to maintain optimal performance and to guard against free flash space exhaustion. He said the most useful application is for datebase. Another thing I think it's worth to mention is that a NV-DRAM memory in NMR/Raptor which is directly exposed to host system. Applications can directly access the NV-DRAM via a memory address - using standard system call mmap(). He said that it is very useful for database logging now. This kind of NVM produces are beginning to appear in recent years, and it is said that Samsung is building a research center in China for related produces. IMHO, NVM will bring an effect to current os layer especially on file system, e.g. its journaling may need to redesign to fully utilize these nonvolatile memory. OCFS2 (led by Canquan Shen) Without a doubt, HuaWei is the biggest contributor to OCFS2 in the past two years. They have posted 46 upstream patches and 39 patches have been merged. Their current project is based on 32/64 nodes cluster, but they also tried 128 nodes at the experimental stage. The major work they are working is to support ATS (atomic test and set), it can be works with DLM at the same time. Looks this idea is inspired by the vmware VMFS locking, i.e, http://blogs.vmware.com/vsphere/2012/05/vmfs-locking-uncovered.html CLK - 18th October 2013 Improving Linux Development with Better Tools (Andi Kleen) This talk focused on how to find/solve bugs along with the Linux complexity growing. Generally, we can do this with the following kind of tools: Static code checkers tools. e.g, sparse, smatch, coccinelle, clang checker, checkpatch, gcc -W/LTO, stanse. This can help check a lot of things, simple mistakes, complex problems, but the challenges are: some are very slow, false positives, may need a concentrated effort to get false positives down. Especially, no static checker I found can follow indirect calls (“OO in C”, common in kernel): struct foo_ops { int (*do_foo)(struct foo *obj); } foo->do_foo(foo); Dynamic runtime checkers, e.g, thread checkers, kmemcheck, lockdep. Ideally all kernel code would come with a test suite, then someone could run all the dynamic checkers. Fuzzers/test suites. e.g, Trinity is a great tool, it finds many bugs, but needs manual model for each syscall. Modern fuzzers around using automatic feedback, but notfor kernel yet: http://taviso.decsystem.org/making_software_dumber.pdf Debuggers/Tracers to understand code, e.g, ftrace, can dump on events/oops/custom triggers, but still too much overhead in many cases to run always during debug. Tools to read/understand source, e.g, grep/cscope work great for many cases, but do not understand indirect pointers (OO in C model used in kernel), give us all “do_foo” instances: struct foo_ops { int (*do_foo)(struct foo *obj); } = { .do_foo = my_foo }; foo>do_foo(foo); That would be great to have a cscope like tool that understands this based on types/initializers XFS: The High Performance Enterprise File System (Jeff Liu) [slides] I gave a talk for introducing the disk layout, unique features, as well as the recent changes.   The slides include some charts to reflect the performances between XFS/Btrfs/Ext4 for small files. About a dozen users raised their hands when I asking who has experienced with XFS. I remembered that when I asked the same question in LinuxCon/Japan, only 3 people raised their hands, but they are Chris Mason, Ric Wheeler, and another attendee. The attendee questions were mainly focused on stability, and comparison with other file systems. Linux Containers (Feng Gao) The speaker introduced us that the purpose for those kind of namespaces, include mount/UTS/IPC/Network/Pid/User, as well as the system API/ABI. For the userspace tools, He mainly focus on the Libvirt LXC rather than us(LXC). Libvirt LXC is another userspace container management tool, implemented as one type of libvirt driver, it can manage containers, create namespace, create private filesystem layout for container, Create devices for container and setup resources controller via cgroup. In this talk, Feng also mentioned another two possible new namespaces in the future, the 1st is the audit, but not sure if it should be assigned to user namespace or not. Another is about syslog, but the question is do we really need it? In-memory Compression (Bob Liu) Same as CLSF, a nice introduction that I have already mentioned above. Misc There were some other talks related to ACPI based memory hotplug, smart wake-affinity in scheduler etc., but my head is not big enough to record all those things. -- Jeff Liu

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  • Running SSIS packages from C#

    - by Piotr Rodak
    Most of the developers and DBAs know about two ways of deploying packages: You can deploy them to database server and run them using SQL Server Agent job or you can deploy the packages to file system and run them using dtexec.exe utility. Both approaches have their pros and cons. However I would like to show you that there is a third way (sort of) that is often overlooked, and it can give you capabilities the ‘traditional’ approaches can’t. I have been working for a few years with applications that run packages from host applications that are implemented in .NET. As you know, SSIS provides programming model that you can use to implement more flexible solutions. SSIS applications are usually thought to be batch oriented, with fairly rigid architecture and processing model, with fixed timeframes when the packages are executed to process data. It doesn’t to be the case, you don’t have to limit yourself to batch oriented architecture. I have very good experiences with service oriented architectures processing large amounts of data. These applications are more complex than what I would like to show here, but the principle stays the same: you can execute packages as a service, on ad-hoc basis. You can also implement and schedule various signals, HTTP calls, file drops, time schedules, Tibco messages and other to run the packages. You can implement event handler that will trigger execution of SSIS when a certain event occurs in StreamInsight stream. This post is just a small example of how you can use the API and other features to create a service that can run SSIS packages on demand. I thought it might be a good idea to implement a restful service that would listen to requests and execute appropriate actions. As it turns out, it is trivial in C#. The application is implemented as console application for the ease of debugging and running. In reality, you might want to implement the application as Windows service. To begin, you have to reference namespace System.ServiceModel.Web and then add a few lines of code: Uri baseAddress = new Uri("http://localhost:8011/");               WebServiceHost svcHost = new WebServiceHost(typeof(PackRunner), baseAddress);                           try             {                 svcHost.Open();                   Console.WriteLine("Service is running");                 Console.WriteLine("Press enter to stop the service.");                 Console.ReadLine();                   svcHost.Close();             }             catch (CommunicationException cex)             {                 Console.WriteLine("An exception occurred: {0}", cex.Message);                 svcHost.Abort();             } The interesting lines are 3, 7 and 13. In line 3 you create a WebServiceHost object. In line 7 you start listening on the defined URL and then in line 13 you shut down the service. As you have noticed, the WebServiceHost constructor is accepting type of an object (here: PackRunner) that will be instantiated as singleton and subsequently used to process the requests. This is the class where you put your logic, but to tell WebServiceHost how to use it, the class must implement an interface which declares methods to be used by the host. The interface itself must be ornamented with attribute ServiceContract. [ServiceContract]     public interface IPackRunner     {         [OperationContract]         [WebGet(UriTemplate = "runpack?package={name}")]         string RunPackage1(string name);           [OperationContract]         [WebGet(UriTemplate = "runpackwithparams?package={name}&rows={rows}")]         string RunPackage2(string name, int rows);     } Each method that is going to be used by WebServiceHost has to have attribute OperationContract, as well as WebGet or WebInvoke attribute. The detailed discussion of the available options is outside of scope of this post. I also recommend using more descriptive names to methods . Then, you have to provide the implementation of the interface: public class PackRunner : IPackRunner     {         ... There are two methods defined in this class. I think that since the full code is attached to the post, I will show only the more interesting method, the RunPackage2.   /// <summary> /// Runs package and sets some of its variables. /// </summary> /// <param name="name">Name of the package</param> /// <param name="rows">Number of rows to export</param> /// <returns></returns> public string RunPackage2(string name, int rows) {     try     {         string pkgLocation = ConfigurationManager.AppSettings["PackagePath"];           pkgLocation = Path.Combine(pkgLocation, name.Replace("\"", ""));           Console.WriteLine();         Console.WriteLine("Calling package {0} with parameter {1}.", name, rows);                  Application app = new Application();         Package pkg = app.LoadPackage(pkgLocation, null);           pkg.Variables["User::ExportRows"].Value = rows;         DTSExecResult pkgResults = pkg.Execute();         Console.WriteLine();         Console.WriteLine(pkgResults.ToString());         if (pkgResults == DTSExecResult.Failure)         {             Console.WriteLine();             Console.WriteLine("Errors occured during execution of the package:");             foreach (DtsError er in pkg.Errors)                 Console.WriteLine("{0}: {1}", er.ErrorCode, er.Description);             Console.WriteLine();             return "Errors occured during execution. Contact your support.";         }                  Console.WriteLine();         Console.WriteLine();         return "OK";     }     catch (Exception ex)     {         Console.WriteLine(ex);         return ex.ToString();     } }   The method accepts package name and number of rows to export. The packages are deployed to the file system. The path to the packages is configured in the application configuration file. This way, you can implement multiple services on the same machine, provided you also configure the URL for each instance appropriately. To run a package, you have to reference Microsoft.SqlServer.Dts.Runtime namespace. This namespace is implemented in Microsoft.SQLServer.ManagedDTS.dll which in my case was installed in the folder “C:\Program Files (x86)\Microsoft SQL Server\100\SDK\Assemblies”. Once you have done it, you can create an instance of Microsoft.SqlServer.Dts.Runtime.Application as in line 18 in the above snippet. It may be a good idea to create the Application object in the constructor of the PackRunner class, to avoid necessity of recreating it each time the service is invoked. Then, in line 19 you see that an instance of Microsoft.SqlServer.Dts.Runtime.Package is created. The method LoadPackage in its simplest form just takes package file name as the first parameter. Before you run the package, you can set its variables to certain values. This is a great way of configuring your packages without all the hassle with dtsConfig files. In the above code sample, variable “User:ExportRows” is set to value of the parameter “rows” of the method. Eventually, you execute the package. The method doesn’t throw exceptions, you have to test the result of execution yourself. If the execution wasn’t successful, you can examine collection of errors exposed by the package. These are the familiar errors you often see during development and debugging of the package. I you run the package from the code, you have opportunity to persist them or log them using your favourite logging framework. The package itself is very simple; it connects to my AdventureWorks database and saves number of rows specified in variable “User::ExportRows” to a file. You should know that before you run the package, you can change its connection strings, logging, events and many more. I attach solution with the test service, as well as a project with two test packages. To test the service, you have to run it and wait for the message saying that the host is started. Then, just type (or copy and paste) the below command to your browser. http://localhost:8011/runpackwithparams?package=%22ExportEmployees.dtsx%22&rows=12 When everything works fine, and you modified the package to point to your AdventureWorks database, you should see "OK” wrapped in xml: I stopped the database service to simulate invalid connection string situation. The output of the request is different now: And the service console window shows more information: As you see, implementing service oriented ETL framework is not a very difficult task. You have ability to configure the packages before you run them, you can implement logging that is consistent with the rest of your system. In application I have worked with we also have resource monitoring and execution control. We don’t allow to run more than certain number of packages to run simultaneously. This ensures we don’t strain the server and we use memory and CPUs efficiently. The attached zip file contains two projects. One is the package runner. It has to be executed with administrative privileges as it registers HTTP namespace. The other project contains two simple packages. This is really a cool thing, you should check it out!

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  • Oracle Solaris: Zones on Shared Storage

    - by Jeff Victor
    Oracle Solaris 11.1 has several new features. At oracle.com you can find a detailed list. One of the significant new features, and the most significant new feature releated to Oracle Solaris Zones, is casually called "Zones on Shared Storage" or simply ZOSS (rhymes with "moss"). ZOSS offers much more flexibility because you can store Solaris Zones on shared storage (surprise!) so that you can perform quick and easy migration of a zone from one system to another. This blog entry describes and demonstrates the use of ZOSS. ZOSS provides complete support for a Solaris Zone that is stored on "shared storage." In this case, "shared storage" refers to fiber channel (FC) or iSCSI devices, although there is one lone exception that I will demonstrate soon. The primary intent is to enable you to store a zone on FC or iSCSI storage so that it can be migrated from one host computer to another much more easily and safely than in the past. With this blog entry, I wanted to make it easy for you to try this yourself. I couldn't assume that you have a SAN available - which is a good thing, because neither do I! What could I use, instead? [There he goes, foreshadowing again... -Ed.] Developing this entry reinforced the lesson that the solution to every lab problem is VirtualBox. Oracle VM VirtualBox (its formal name) helps here in a couple of important ways. It offers the ability to easily install multiple copies of Solaris as guests on top of any popular system (Microsoft Windows, MacOS, Solaris, Oracle Linux (and other Linuxes) etc.). It also offers the ability to create a separate virtual disk drive (VDI) that appears as a local hard disk to a guest. This virtual disk can be moved very easily from one guest to another. In other words, you can follow the steps below on a laptop or larger x86 system. Please note that the ability to use ZOSS to store a zone on a local disk is very useful for a lab environment, but not so useful for production. I do not suggest regularly moving disk drives among computers. In the method I describe below, that virtual hard disk will contain the zone that will be migrated among the (virtual) hosts. In production, you would use FC or iSCSI LUNs instead. The zonecfg(1M) man page details the syntax for each of the three types of devices. Why Migrate? Why is the migration of virtual servers important? Some of the most common reasons are: Moving a workload to a different computer so that the original computer can be turned off for extensive maintenance. Moving a workload to a larger system because the workload has outgrown its original system. If the workload runs in an environment (such as a Solaris Zone) that is stored on shared storage, you can restore the service of the workload on an alternate computer if the original computer has failed and will not reboot. You can simplify lifecycle management of a workload by developing it on a laptop, migrating it to a test platform when it's ready, and finally moving it to a production system. Concepts For ZOSS, the important new concept is named "rootzpool". You can read about it in the zonecfg(1M) man page, but here's the short version: it's the backing store (hard disk(s), or LUN(s)) that will be used to make a ZFS zpool - the zpool that will hold the zone. This zpool: contains the zone's Solaris content, i.e. the root file system does not contain any content not related to the zone can only be mounted by one Solaris instance at a time Method Overview Here is a brief list of the steps to create a zone on shared storage and migrate it. The next section shows the commands and output. You will need a host system with an x86 CPU (hopefully at least a couple of CPU cores), at least 2GB of RAM, and at least 25GB of free disk space. (The steps below will not actually use 25GB of disk space, but I don't want to lead you down a path that ends in a big sign that says "Your HDD is full. Good luck!") Configure the zone on both systems, specifying the rootzpool that both will use. The best way is to configure it on one system and then copy the output of "zonecfg export" to the other system to be used as input to zonecfg. This method reduces the chances of pilot error. (It is not necessary to configure the zone on both systems before creating it. You can configure this zone in multiple places, whenever you want, and migrate it to one of those places at any time - as long as those systems all have access to the shared storage.) Install the zone on one system, onto shared storage. Boot the zone. Provide system configuration information to the zone. (In the Real World(tm) you will usually automate this step.) Shutdown the zone. Detach the zone from the original system. Attach the zone to its new "home" system. Boot the zone. The zone can be used normally, and even migrated back, or to a different system. Details The rest of this shows the commands and output. The two hostnames are "sysA" and "sysB". Note that each Solaris guest might use a different device name for the VDI that they share. I used the device names shown below, but you must discover the device name(s) after booting each guest. In a production environment you would also discover the device name first and then configure the zone with that name. Fortunately, you can use the command "zpool import" or "format" to discover the device on the "new" host for the zone. The first steps create the VirtualBox guests and the shared disk drive. I describe the steps here without demonstrating them. Download VirtualBox and install it using a method normal for your host OS. You can read the complete instructions. Create two VirtualBox guests, each to run Solaris 11.1. Each will use its own VDI as its root disk. Install Solaris 11.1 in each guest.Install Solaris 11.1 in each guest. To install a Solaris 11.1 guest, you can either download a pre-built VirtualBox guest, and import it, or install Solaris 11.1 from the "text install" media. If you use the latter method, after booting you will not see a windowing system. To install the GUI and other important things, login and run "pkg install solaris-desktop" and take a break while it installs those important things. Life is usually easier if you install the VirtualBox Guest Additions because then you can copy and paste between the host and guests, etc. You can find the guest additions in the folder matching the version of VirtualBox you are using. You can also read the instructions for installing the guest additions. To create the zone's shared VDI in VirtualBox, you can open the storage configuration for one of the two guests, select the SATA controller, and click on the "Add Hard Disk" icon nearby. Choose "Create New Disk" and specify an appropriate path name for the file that will contain the VDI. The shared VDI must be at least 1.5 GB. Note that the guest must be stopped to do this. Add that VDI to the other guest - using its Storage configuration - so that each can access it while running. The steps start out the same, except that you choose "Choose Existing Disk" instead of "Create New Disk." Because the disk is configured on both of them, VirtualBox prevents you from running both guests at the same time. Identify device names of that VDI, in each of the guests. Solaris chooses the name based on existing devices. The names may be the same, or may be different from each other. This step is shown below as "Step 1." Assumptions In the example shown below, I make these assumptions. The guest that will own the zone at the beginning is named sysA. The guest that will own the zone after the first migration is named sysB. On sysA, the shared disk is named /dev/dsk/c7t2d0 On sysB, the shared disk is named /dev/dsk/c7t3d0 (Finally!) The Steps Step 1) Determine the name of the disk that will move back and forth between the systems. root@sysA:~# format Searching for disks...done AVAILABLE DISK SELECTIONS: 0. c7t0d0 /pci@0,0/pci8086,2829@d/disk@0,0 1. c7t2d0 /pci@0,0/pci8086,2829@d/disk@2,0 Specify disk (enter its number): ^D Step 2) The first thing to do is partition and label the disk. The magic needed to write an EFI label is not overly complicated. root@sysA:~# format -e c7t2d0 selecting c7t2d0 [disk formatted] FORMAT MENU: ... format fdisk No fdisk table exists. The default partition for the disk is: a 100% "SOLARIS System" partition Type "y" to accept the default partition, otherwise type "n" to edit the partition table. n SELECT ONE OF THE FOLLOWING: ... Enter Selection: 1 ... G=EFI_SYS 0=Exit? f SELECT ONE... ... 6 format label ... Specify Label type[1]: 1 Ready to label disk, continue? y format quit root@sysA:~# ls /dev/dsk/c7t2d0 /dev/dsk/c7t2d0 Step 3) Configure zone1 on sysA. root@sysA:~# zonecfg -z zone1 Use 'create' to begin configuring a new zone. zonecfg:zone1 create create: Using system default template 'SYSdefault' zonecfg:zone1 set zonename=zone1 zonecfg:zone1 set zonepath=/zones/zone1 zonecfg:zone1 add rootzpool zonecfg:zone1:rootzpool add storage dev:dsk/c7t2d0 zonecfg:zone1:rootzpool end zonecfg:zone1 exit root@sysA:~# oot@sysA:~# zonecfg -z zone1 info zonename: zone1 zonepath: /zones/zone1 brand: solaris autoboot: false bootargs: file-mac-profile: pool: limitpriv: scheduling-class: ip-type: exclusive hostid: fs-allowed: anet: ... rootzpool: storage: dev:dsk/c7t2d0 Step 4) Install the zone. This step takes the most time, but you can wander off for a snack or a few laps around the gym - or both! (Just not at the same time...) root@sysA:~# zoneadm -z zone1 install Created zone zpool: zone1_rpool Progress being logged to /var/log/zones/zoneadm.20121022T163634Z.zone1.install Image: Preparing at /zones/zone1/root. AI Manifest: /tmp/manifest.xml.RXaycg SC Profile: /usr/share/auto_install/sc_profiles/enable_sci.xml Zonename: zone1 Installation: Starting ... Creating IPS image Startup linked: 1/1 done Installing packages from: solaris origin: http://pkg.us.oracle.com/support/ DOWNLOAD PKGS FILES XFER (MB) SPEED Completed 183/183 33556/33556 222.2/222.2 2.8M/s PHASE ITEMS Installing new actions 46825/46825 Updating package state database Done Updating image state Done Creating fast lookup database Done Installation: Succeeded Note: Man pages can be obtained by installing pkg:/system/manual done. Done: Installation completed in 1696.847 seconds. Next Steps: Boot the zone, then log into the zone console (zlogin -C) to complete the configuration process. Log saved in non-global zone as /zones/zone1/root/var/log/zones/zoneadm.20121022T163634Z.zone1.install Step 5) Boot the Zone. root@sysA:~# zoneadm -z zone1 boot Step 6) Login to zone's console to complete the specification of system information. root@sysA:~# zlogin -C zone1 Answer the usual questions and wait for a login prompt. Then you can end the console session with the usual "~." incantation. Step 7) Shutdown the zone so it can be "moved." root@sysA:~# zoneadm -z zone1 shutdown Step 8) Detach the zone so that the original global zone can't use it. root@sysA:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 installed /zones/zone1 solaris excl root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - zone1_rpool 1.98G 484M 1.51G 23% 1.00x ONLINE - root@sysA:~# zoneadm -z zone1 detach Exported zone zpool: zone1_rpool Step 9) Review the result and shutdown sysA so that sysB can use the shared disk. root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - root@sysA:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 configured /zones/zone1 solaris excl root@sysA:~# init 0 Step 10) Now boot sysB and configure a zone with the parameters shown above in Step 1. (Again, the safest method is to use "zonecfg ... export" on sysA as described in section "Method Overview" above.) The one difference is the name of the rootzpool storage device, which was shown in the list of assumptions, and which you must determine by booting sysB and using the "format" or "zpool import" command. When that is done, you should see the output shown next. (I used the same zonename - "zone1" - in this example, but you can choose any valid zonename you want.) root@sysB:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 configured /zones/zone1 solaris excl root@sysB:~# zonecfg -z zone1 info zonename: zone1 zonepath: /zones/zone1 brand: solaris autoboot: false bootargs: file-mac-profile: pool: limitpriv: scheduling-class: ip-type: exclusive hostid: fs-allowed: anet: linkname: net0 ... rootzpool: storage: dev:dsk/c7t3d0 Step 11) Attaching the zone automatically imports the zpool. root@sysB:~# zoneadm -z zone1 attach Imported zone zpool: zone1_rpool Progress being logged to /var/log/zones/zoneadm.20121022T184034Z.zone1.attach Installing: Using existing zone boot environment Zone BE root dataset: zone1_rpool/rpool/ROOT/solaris Cache: Using /var/pkg/publisher. Updating non-global zone: Linking to image /. Processing linked: 1/1 done Updating non-global zone: Auditing packages. No updates necessary for this image. Updating non-global zone: Zone updated. Result: Attach Succeeded. Log saved in non-global zone as /zones/zone1/root/var/log/zones/zoneadm.20121022T184034Z.zone1.attach root@sysB:~# zoneadm -z zone1 boot root@sysB:~# zlogin zone1 [Connected to zone 'zone1' pts/2] Oracle Corporation SunOS 5.11 11.1 September 2012 Step 12) Now let's migrate the zone back to sysA. Create a file in zone1 so we can verify it exists after we migrate the zone back, then begin migrating it back. root@zone1:~# ls /opt root@zone1:~# touch /opt/fileA root@zone1:~# ls -l /opt/fileA -rw-r--r-- 1 root root 0 Oct 22 14:47 /opt/fileA root@zone1:~# exit logout [Connection to zone 'zone1' pts/2 closed] root@sysB:~# zoneadm -z zone1 shutdown root@sysB:~# zoneadm -z zone1 detach Exported zone zpool: zone1_rpool root@sysB:~# init 0 Step 13) Back on sysA, check the status. Oracle Corporation SunOS 5.11 11.1 September 2012 root@sysA:~# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - zone1 configured /zones/zone1 solaris excl root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - Step 14) Re-attach the zone back to sysA. root@sysA:~# zoneadm -z zone1 attach Imported zone zpool: zone1_rpool Progress being logged to /var/log/zones/zoneadm.20121022T190441Z.zone1.attach Installing: Using existing zone boot environment Zone BE root dataset: zone1_rpool/rpool/ROOT/solaris Cache: Using /var/pkg/publisher. Updating non-global zone: Linking to image /. Processing linked: 1/1 done Updating non-global zone: Auditing packages. No updates necessary for this image. Updating non-global zone: Zone updated. Result: Attach Succeeded. Log saved in non-global zone as /zones/zone1/root/var/log/zones/zoneadm.20121022T190441Z.zone1.attach root@sysA:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 17.6G 11.2G 6.47G 63% 1.00x ONLINE - zone1_rpool 1.98G 491M 1.51G 24% 1.00x ONLINE - root@sysA:~# zoneadm -z zone1 boot root@sysA:~# zlogin zone1 [Connected to zone 'zone1' pts/2] Oracle Corporation SunOS 5.11 11.1 September 2012 root@zone1:~# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT rpool 1.98G 538M 1.46G 26% 1.00x ONLINE - Step 15) Check for the file created on sysB, earlier. root@zone1:~# ls -l /opt total 1 -rw-r--r-- 1 root root 0 Oct 22 14:47 fileA Next Steps Here is a brief list of some of the fun things you can try next. Add space to the zone by adding a second storage device to the rootzpool. Make sure that you add it to the configurations of both zones! Create a new zone, specifying two disks in the rootzpool when you first configure the zone. When you install that zone, or clone it from another zone, zoneadm uses those two disks to create a mirrored pool. (Three disks will result in a three-way mirror, etc.) Conclusion Hopefully you have seen the ease with which you can now move Solaris Zones from one system to another.

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  • SQLAuthority News – Job Interviewing the Right Way (and for the Right Reasons) – Guest Post by Feodor Georgiev

    - by pinaldave
    Feodor Georgiev is a SQL Server database specialist with extensive experience of thinking both within and outside the box. He has wide experience of different systems and solutions in the fields of architecture, scalability, performance, etc. Feodor has experience with SQL Server 2000 and later versions, and is certified in SQL Server 2008. Feodor has written excellent article on Job Interviewing the Right Way. Here is his article in his own language. A while back I was thinking to start a blog post series on interviewing and employing IT personnel. At that time I had just read the ‘Smart and gets things done’ book (http://www.joelonsoftware.com/items/2007/06/05.html) and I was hyped up on some debatable topics regarding finding and employing the best people in the branch. I have no problem with hiring the best of the best; it’s just the definition of ‘the best of the best’ that makes things a bit more complicated. One of the fundamental books one can read on the topic of interviewing is the one mentioned above. If you have not read it, then you must do so; not because it contains the ultimate truth, and not because it gives the answers to most questions on the subject, but because the book contains an extensive set of questions about interviewing and employing people. Of course, a big part of these questions have different answers, depending on location, culture, available funds and so on. (What works in the US may not necessarily work in the Nordic countries or India, or it may work in a different way). The only thing that is valid regardless of any external factor is this: curiosity. In my belief there are two kinds of people – curious and not-so-curious; regardless of profession. Think about it – professional success is directly proportional to the individual’s curiosity + time of active experience in the field. (I say ‘active experience’ because vacations and any distractions do not count as experience :)  ) So, curiosity is the factor which will distinguish a good employee from the not-so-good one. But let’s shift our attention to something else for now: a few tips and tricks for successful interviews. Tip and trick #1: get your priorities straight. Your status usually dictates your priorities; for example, if the person looking for a job has just relocated to a new country, they might tend to ignore some of their priorities and overload others. In other words, setting priorities straight means to define the personal criteria by which the interview process is lead. For example, similar to the following questions can help define the criteria for someone looking for a job: How badly do I need a (any) job? Is it more important to work in a clean and quiet environment or is it important to get paid well (or both, if possible)? And so on… Furthermore, before going to the interview, the candidate should have a list of priorities, sorted by the most importance: e.g. I want a quiet environment, x amount of money, great helping boss, a desk next to a window and so on. Also it is a good idea to be prepared and know which factors can be compromised and to what extent. Tip and trick #2: the interview is a two-way street. A job candidate should not forget that the interview process is not a one-way street. What I mean by this is that while the employer is interviewing the potential candidate, the job seeker should not miss the chance to interview the employer. Usually, the employer and the candidate will meet for an interview and talk about a variety of topics. In a quality interview the candidate will be presented to key members of the team and will have the opportunity to ask them questions. By asking the right questions both parties will define their opinion about each other. For example, if the candidate talks to one of the potential bosses during the interview process and they notice that the potential manager has a hard time formulating a question, then it is up to the candidate to decide whether working with such person is a red flag for them. There are as many interview processes out there as there are companies and each one is different. Some bigger companies and corporates can afford pre-selection processes, 3 or even 4 stages of interviews, small companies usually settle with one interview. Some companies even give cognitive tests on the interview. Why not? In his book Joel suggests that a good candidate should be pampered and spoiled beyond belief with a week-long vacation in New York, fancy hotels, food and who knows what. For all I can imagine, an interview might even take place at the top of the Eifel tower (right, Mr. Joel, right?) I doubt, however, that this is the optimal way to capture the attention of a good employee. The ‘curiosity’ topic What I have learned so far in my professional experience is that opinions can be subjective. Plus, opinions on technology subjects can also be subjective. According to Joel, only hiring the best of the best is worth it. If you ask me, there is no such thing as best of the best, simply because human nature (well, aside from some physical limitations, like putting your pants on through your head :) ) has no boundaries. And why would it have boundaries? I have seen many curious and interesting people, naturally good at technology, though uninterested in it as one  can possibly be; I have also seen plenty of people interested in technology, who (in an ideal world) should have stayed far from it. At any rate, all of this sums up at the end to the ‘supply and demand’ factor. The interview process big-bang boils down to this: If there is a mutual benefit for both the employer and the potential employee to work together, then it all sorts out nicely. If there is no benefit, then it is much harder to get to a common place. Tip and trick #3: word-of-mouth is worth a thousand words Here I would just mention that the best thing a job candidate can get during the interview process is access to future team members or other employees of the new company. Nowadays the world has become quite small and everyone knows everyone. Look at LinkedIn, look at other professional networks and you will realize how small the world really is. Knowing people is a good way to become more approachable and to approach them. Tip and trick #4: Be confident. It is true that for some people confidence is as natural as breathing and others have to work hard to express it. Confidence is, however, a key factor in convincing the other side (potential employer or employee) that there is a great chance for success by working together. But it cannot get you very far if it’s not backed up by talent, curiosity and knowledge. Tip and trick #5: The right reasons What really bothers me in Sweden (and I am sure that there are similar situations in other countries) is that there is a tendency to fill quotas and to filter out candidates by criteria different from their skill and knowledge. In job ads I see quite often the phrases ‘positive thinker’, ‘team player’ and many similar hints about personality features. So my guess here is that discrimination has evolved to a new level. Let me clear up the definition of discrimination: ‘unfair treatment of a person or group on the basis of prejudice’. And prejudice is the ‘partiality that prevents objective consideration of an issue or situation’. In other words, there is not much difference whether a job candidate is filtered out by race, gender or by personality features – it is all a bad habit. And in reality, there is no proven correlation between the technology knowledge paired with skills and the personal features (gender, race, age, optimism). It is true that a significantly greater number of Darwin awards were given to men than to women, but I am sure that somewhere there is a paper or theory explaining the genetics behind this. J This topic actually brings to mind one of my favorite work related stories. A while back I was working for a big company with many teams involved in their processes. One of the teams was occupying 2 rooms – one had the team members and was full of light, colorful posters, chit-chats and giggles, whereas the other room was dark, lighted only by a single monitor with a quiet person in front of it. Later on I realized that the ‘dark room’ person was the guru and the ultimate problem-solving-brain who did not like the chats and giggles and hence was in a separate room. In reality, all severe problems which the chatty and cheerful team members could not solve and all emergencies were directed to ‘the dark room’. And thus all worked out well. The moral of the story: Personality has nothing to do with technology knowledge and skills. End of story. Summary: I’d like to stress the fact that there is no ultimately perfect candidate for a job, and there is no such thing as ‘best-of-the-best’. From my personal experience, the main criteria by which I measure people (co-workers and bosses) is the curiosity factor; I know from experience that the more curious and inventive a person is, the better chances there are for great achievements in their field. Related stories: (for extra credit) 1) Get your priorities straight. A while back as a consultant I was working for a few days at a time at different offices and for different clients, and so I was able to compare and analyze the work environments. There were two different places which I compared and recently I asked a friend of mine the following question: “Which one would you prefer as a work environment: a noisy office full of people, or a quiet office full of faulty smells because the office is rarely cleaned?” My friend was puzzled for a while, thought about it and said: “Hmm, you are talking about two different kinds of pollution… I will probably choose the second, since I can clean the workplace myself a bit…” 2) The interview is a two-way street. One time, during a job interview, I met a potential boss that had a hard time phrasing a question. At that particular time it was clear to me that I would not have liked to work under this person. According to my work religion, the properly asked question contains at least half of the answer. And if I work with someone who cannot ask a question… then I’d be doing double or triple work. At another interview, after the technical part with the team leader of the department, I was introduced to one of the team members and we were left alone for 5 minutes. I immediately jumped on the occasion and asked the blunt question: ‘What have you learned here for the past year and how do you like your job?’ The team member looked at me and said ‘Nothing really. I like playing with my cats at home, so I am out of here at 5pm and I don’t have time for much.’ I was disappointed at the time and I did not take the job offer. I wasn’t that shocked a few months later when the company went bankrupt. 3) The right reasons to take a job: personality check. A while back I was asked to serve as a job reference for a coworker. I agreed, and after some weeks I got a phone call from the company where my colleague was applying for a job. The conversation started with the manager’s question about my colleague’s personality and about their social skills. (You can probably guess what my internal reaction was… J ) So, after 30 minutes of pouring common sense into the interviewer’s head, we finally agreed on the fact that a shy or quiet personality has nothing to do with work skills and knowledge. Some years down the road my former colleague is taking the manager’s position as the manager is demoted to a different department. Reference: Feodor Georgiev, Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Create Your CRM Style

    - by Ruth
    Company branding can create a sense of spirit, belonging, familiarity, and fun. CRM On Demand has long offered company branding options, but now, with Release 17, those options have become quicker, easier, and more flexible. Themes (also known as Skins) allow you to customize the appearance of the CRM On Demand application for your entire company, or for individual roles. Users may also select the theme that works best for them. You can create a new theme in 5 minutes or less, but if you're anything like me, you may enjoy tinkering with it for a while longer. Before you begin tinkering, I recommend spending a few moments coming up with a design plan. If you have specific colors or logos you want for your theme, gather those first...that will move the process along much faster. If you want to match the color of an existing Web site or application, you can use tools, like Pixie, to match the HEX/HTML color values. Logos must be in a JPEG, JPG, PNG, or GIF file format. Header logos must be approximately 70 pixels high by 1680 pixels wide. Footer logos must be no more than 200 pixels wide. And, of course, you must have permission to use the images that you upload for your theme. Creating the theme itself is the simple part. Here are a few simple steps. Note: You must have the Manage Themes privilege to create custom themes. Click the Admin global link. Navigate to Application Customization Themes. Click New. Note: You may also choose to copy and edit and existing theme. Enter information for the following fields: Theme Name - Enter a name for your new theme. Show Default Help Link - Online help holds valuable information for all users, so I recommend selecting this check box. Show Default Training and Support Link - The Training and Support Center holds valuable information for all users, so I recommend selecting this check box. Description - Enter a description for your new theme. Click Save. Once you click Save, the Theme Detail page opens. From there, you can design your theme. The preview shows the Home, Detail, and List pages, with the new theme applied. For more detailed information about themes, click the Help link from any page in CRM On Demand Release 17, then search or browse to find the Creating New Themes page (Administering CRM On Demand Application Customization Creating New Themes). Click the Show Me link on that Help page to access the Creating Custom Themes quick guide. This quick guide shows how each of the page elements are defined.

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  • AIX Checklist for stable obiee deployment

    - by user554629
    Common AIX configuration issues     ( last updated 27 Aug 2012 ) OBIEE is a complicated system with many moving parts and connection points.The purpose of this article is to provide a checklist to discuss OBIEE deployment with your systems administrators. The information in this article is time sensitive, and updated as I discover new  issues or details. What makes OBIEE different? When Tech Support suggests AIX component upgrades to a stable, locked-down production AIX environment, it is common to get "push back".  "Why is this necessary?  We aren't we seeing issues with other software?"It's a fair question that I have often struggled to answer; here are the talking points: OBIEE is memory intensive.  It is the entire purpose of the software to trade memory for repetitive, more expensive database requests across a network. OBIEE is implemented in C++ and is very dependent on the C++ runtime to behave correctly. OBIEE is aggressively thread efficient;  if atomic operations on a particular architecture do not work correctly, the software crashes. OBIEE dynamically loads third-party database client libraries directly into the nqsserver process.  If the library is not thread-safe, or corrupts process memory the OBIEE crash happens in an unrelated part of the code.  These are extremely difficult bugs to find. OBIEE software uses 99% common source across multiple platforms:  Windows, Linux, AIX, Solaris and HPUX.  If a crash happens on only one platform, we begin to suspect other factors.  load intensity, system differences, configuration choices, hardware failures.  It is rare to have a single product require so many diverse technical skills.   My role in support is to understand system configurations, performance issues, and crashes.   An analyst trained in Business Analytics can't be expected to know AIX internals in the depth required to make configuration choices.  Here are some guidelines. AIX C++ Runtime must be at  version 11.1.0.4$ lslpp -L | grep xlC.aixobiee software will crash if xlC.aix.rte is downlevel;  this is not a "try it" suggestion.Nov 2011 11.1.0.4 version  is appropriate for all AIX versions ( 5, 6, 7 )Download from here:https://www-304.ibm.com/support/docview.wss?uid=swg24031426 No reboot is necessary to install, it can even be installed while applications are using the current version.Restart the apps, and they will pick up the latest version. AIX 5.3 Technology Level 12 is required when running on Power5,6,7 processorsAIX 6.1 was introduced with the newer Power chips, and we have seen no issues with 6.1 or 7.1 versions.Customers with an unstable deployment, dozens of unexplained crashes, became stable after the upgrade.If your AIX system is 5.3, the minimum TL level should be at or higher than this:$ oslevel -s  5300-12-03-1107IBM typically supports only the two latest versions of AIX ( 6.1 and 7.1, for example).  AIX 5.3 is still supported and popular running in an LPAR. obiee userid limits$ ulimit -Ha  ( hard limits )$ ulimit -a   ( default limits )core file size (blocks)     unlimiteddata seg size (kbytes)      unlimitedfile size (blocks)          unlimitedmax memory size (kbytes)    unlimitedopen files                  10240 cpu time (seconds)          unlimitedvirtual memory (kbytes)     unlimitedIt is best to establish the values in /etc/security/limitsroot user is needed to observe and modify this file.If you modify a limit, you will need to relog in to change it again.  For example,$ ulimit -c 0$ ulimit -c 2097151cannot modify limit: Operation not permitted$ ulimit -c unlimited$ ulimit -c0There are only two meaningful values for ulimit -c ; zero or unlimited.Anything else is likely to produce a truncated core file that cannot be analyzed. Deploy 32-bit or 64-bit ?Early versions of OBIEE offered 32-bit or 64-bit choice to AIX customers.The 32-bit choice was needed if a database vendor did not supply a 64-bit client library.That's no longer an issue and beginning with OBIEE 11, 32-bit code is no longer shipped.A common error that leads to "out of memory" conditions to to accept the 32-bit memory configuration choices on 64-bit deployments.  The significant configuration choices are: Maximum process data (heap) size is in an AIX environment variableLDR_CNTRL=IGNOREUNLOAD@LOADPUBLIC@PREREAD_SHLIB@MAXDATA=0x... Two thread stack sizes are made in obiee NQSConfig.INI[ SERVER ]SERVER_THREAD_STACK_SIZE = 0;DB_GATEWAY_THREAD_STACK_SIZE = 0; Sort memory in NQSConfig.INI[ GENERAL ]SORT_MEMORY_SIZE = 4 MB ;SORT_BUFFER_INCREMENT_SIZE = 256 KB ; Choosing a value for MAXDATA:0x080000000  2GB Default maximum 32-bit heap size ( 8 with 7 zeros )0x100000000  4GB 64-bit breaking even with 32-bit ( 1 with 8 zeros )0x200000000  8GB 64-bit double 32-bit max0x400000000 16GB 64-bit safetyUsing 2GB heap size for a 64-bit process will almost certainly lead to an out-of-memory situation.Registers are twice as big ... consume twice as much memory in the heap.Upgrading to a 4GB heap for a 64-bit process is just "breaking even" with 32-bit.A 32-bit process is constrained by the 32-bit virtual addressing limits.  Heap memory is used for dynamic requirements of obiee software, thread stacks for each of the configured threads, and sometimes for shared libraries. 64-bit processes are not constrained in this way;  extra heap space can be configured for safety against a query that might create a sudden requirement for excessive storage.  If the storage is not available, this query might crash the whole server and disrupt existing users.There is no performance penalty on AIX for configuring more memory than required;  extra memory can be configured for safety.  If there are no other considerations, start with 8GB.Choosing a value for Thread Stack size:zero is the value documented to select an appropriate default for thread stack size.  My preference is to change this to an absolute value, even if you intend to use the documented default;  it provides better documentation and removes the "surprise" factor.There are two thread types that can be configured. GATEWAY is used by a thread pool to call a database client library to establish a DB connection.The default size is 256KB;  many customers raise this to 512KB ( no performance penalty for over-configuring ). This value must be set to 1 MB if Teradata connections are used. SERVER threads are used to run queries.  OBIEE uses recursive algorithms during the analysis of query structures which can consume significant thread stack storage.  It's difficult to provide guidance on a value that depends on data and complexity.  The general notion is to provide more space than you think you need,  "double down" and increase the value if you run out, otherwise inspect the query to understand why it is too complex for the thread stack.  There are protections built into the software to abort a single user query that is too complex, but the algorithms don't cover all situations.256 KB  The default 32-bit stack size.  Many customers increased this to 512KB on 32-bit.  A 64-bit server is very likely to crash with this value;  the stack contains mostly register values, which are twice as big.512 KB  The documented 64-bit default.  Some early releases of obiee didn't set this correctly, resulting in 256KB stacks.1 MB  The recommended 64-bit setting.  If your system only ever uses 512KB of stack space, there is no performance penalty for using 1MB stack size.2 MB  Many large customers use this value for safety.  No performance penalty.nqscheduler does not use the NQSConfig.INI file to set thread stack size.If this process crashes because the thread stack is too small, use this to set 2MB:export OBI_BACKGROUND_STACK_SIZE=2048 Shared libraries are not (shared) When application libraries are loaded at run-time, AIX makes a decision on whether to load the libraries in a "public" memory segment.  If the filesystem library permissions do not have the "Read-Other" permission bit, AIX loads the library into private process memory with two significant side-effects:* The libraries reduce the heap storage available.      Might be significant in 32-bit processes;  irrelevant in 64-bit processes.* Library code is loaded into multiple real pages for execution;  one copy for each process.Multiple execution images is a significant issue for both 32- and 64-bit processes.The "real memory pages" saved by using public memory segments is a minor concern.  Today's machines typically have plenty of real memory.The real problem with private copies of libraries is that they consume processor cache blocks, which are limited.   The same library instructions executing in different real pages will cause memory delays as the i-cache ( instruction cache 128KB blocks) are refreshed from real memory.   Performance loss because instructions are delayed is something that is difficult to measure without access to low-level cache fault data.   The machine just appears to be running slowly for no observable reason.This is an easy problem to detect, and an easy problem to correct.Detection:  "genld -l" AIX command produces a list of the libraries used by each process and the AIX memory address where they are loaded.32-bit public segment is 13 ( "dxxxxxxx" ).   private segments are 2-a.64-bit public segment is 9 ( "9xxxxxxxxxxxxxxx") ; private segment is 8.genld -l | grep -v ' d| 9' | sort +2provides a list of privately loaded libraries. Repair: chmod o+r <libname>AIX shared libraries will have a suffix of ".so" or ".a".Another technique is to change all libraries in a selected directory to repair those that might not be currently loaded.   The usual directories that need repair are obiee code, httpd code and plugins, database client libraries and java.chmod o+r /shr/dir/*.a /shr/dir/*.so Configure your system for diagnosticsProduction systems shouldn't crash, and yet bad things happen to good software.If obiee software crashes and produces a core, you should configure your system for reliable transfer of the failing conditions to Oracle Tech Support.  Here's what we need to be able to diagnose a core file from your system.* fullcore enabled. chdev -lsys0 -a fullcore=true* core naming enabled. chcore -n on -d* ulimit must not truncate core. see item 3.* pstack.sh is used to capture core documentation.* obidoc is used to capture current AIX configuration.* snapcore  AIX utility captures core and libraries. Use the proper syntax. $ snapcore -r corename executable-fullpath   /tmp/snapcore will contain the .pax.Z output file.  It is compressed.* If cores are directed to a common directory, ensure obiee userid can write to the directory.  ( chcore -p /cores -d ; chmod 777 /cores )The filesystem must have sufficient space to hold a crashing obiee application.Use:  df -k  Check the "Free" column ( not "% Used" )  8388608 is 8GB. Disable Oracle Client Library signal handlingThe Oracle DB Client Library is frequently distributed with the sqlplus development kit.By default, the library enables a signal handler, which will document a call stack if the application crashes.   The signal handler is not needed, and definitely disruptive to obiee diagnostics.   It needs to be disabled.   sqlnet.ora is typically located at:   $ORACLE_HOME/network/admin/sqlnet.oraAdd this line at the top of the file:   DIAG_SIGHANDLER_ENABLED=FALSE Disable async query in the RPD connection pool.This might be an obiee 10.1.3.4 issue only ( still checking  )."async query" must be disabled in the connection pools.It was designed to enable query cancellation to a database, and turned out to have too many edge conditions in normal communication that produced random corruption of data and crashes.  Please ensure it is turned off in the RPD. Check AIX error report (errpt).Errors external to obiee applications can trigger crashes.  $ /bin/errpt -aHardware errors ( firmware, adapters, disks ) should be reported to IBM support.All application core files are recorded by AIX;  the most recent ones are listed first. Reserved for something important to say.

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