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  • Database per application VS One big database for all applications

    - by Jorge Vargas
    Hello, I'm designing a few applications that will share 2 or 3 database tables and all of the other tables will be independent of each app. The shared databases contain mostly user information, and there might occur the case where other tables need to be shared, but that's my instinct speaking. I'm leaning over the one database for all applications solution because I want to have referential integrity, and I won't have to keep the same information up to date in each of the databases, but I'm probably going to end with a database of 100+ tables where only groups of ten tables will have related information. The database per application approach helps me keep everything more organized, but I don't know a way to keep the related tables in all databases up to date. So, the basic question is: which of both approaches do you recommend? Thanks, Jorge Vargas.

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  • How To Remove People and Objects From Photographs In Photoshop

    - by Eric Z Goodnight
    You might think that it’s a complicated process to remove objects from photographs. But really Photoshop makes it quite simple, even when removing all traces of a person from digital photographs. Read on to see just how easy it is. Photoshop was originally created to be an image editing program, and it excels at it. With hardly any Photoshop experience, any beginner can begin removing objects or people from their photos. Have some friends that photobombed an otherwise great pic? Tell them to say their farewells, because here’s how to get rid of them with Photoshop! Tools for Removing Objects Removing an object is not really “magical” work. Your goal is basically to cover up the information you don’t want in an image with information you do want. In this sample image, we want to remove the cigar smoking man, and leave the geisha. Here’s a couple of the tools that can be useful to work with when attempting this kind of task. Clone Stamp and Pattern Stamp Tool: Samples parts of your image from your background, and allows you to paint into your image with your mouse or stylus. Eraser and Brush Tools: Paint flat colors and shapes, and erase cloned layers of image information. Basic, down and dirty photo editing tools. Pen, Quick Selection, Lasso, and Crop tools: Select, isolate, and remove parts of your image with these selection tools. All useful in their own way. Some, like the pen tool, are nightmarishly tough on beginners. Remove a Person with the Clone Stamp Tool (Video) The video above uses the Clone Stamp tool to sample and paint with the background texture. It’s a simple tool to use, although it can be confusing, possibly counter-intuitive. Here’s some pointers, in addition to the video above. Select shortcut key to choose the Clone tool stamp from the Tools Panel. Always create a copy of your background layer before doing heavy edits by right clicking on the background in your Layers Panel and selecting “Duplicate.” Hold with the Clone Tool selected, and click anywhere in your image to sample that area. When you’re sampling an area, your cursor is “Aligned” with your sample area. When you paint, your sample area moves. You can turn the “Aligned” setting off by clicking the in the Options Panel at the top of your screen if you want. Change your brush size and hardness as shown in the video by right-clicking in your image. Use your lasso to copy and paste pieces of your image in order to cover up any parts that seem appropriate. Photoshop Magic with the “Content-Aware Fill” One of the hallmark features of CS5 is the “Content-Aware Fill.” Content aware fill can be an excellent shortcut to removing objects and even people in Photoshop, but it is somewhat limited, and can get confused. Here’s a basic rundown on how it works. Select an object using your Lasso tool, shortcut key . The Lasso works fine as this selection can be rough. Navigate to Edit > Fill, and select “Content-Aware,” as illustrated above, from the pull-down menu. It’s surprisingly simple. After some processing, Photoshop has done the work of removing the object for you. It takes a few moments, and it is not perfect, so be prepared to touch it up with some Copy-Paste, or some Clone stamp action. Content Aware Fill Has Its Limits Keep in mind that the Content Aware Fill is meant to be used with other techniques in mind. It doesn’t always perform perfectly, but can give you a great starting point. Take this image for instance. It is actually plausible to hide this figure and make this image look like he was never there at all. With a selection made with the Lasso tool, navigate to Edit > Fill and select “Content Aware” again. The result is surprisingly good, but as you can see, worthy of some touch up. With a result like this one, you’ll have to get your hands dirty with copy-paste to create believable lines in the background. With many photographs, Content Aware Fill will simply get confused and give you results you won’t be happy with. Additional Touch Up for Bad Background Textures with the Pattern Stamp Tool For the perfectionist, cleaning up the lumpy looking textures that the Clone Stamp can leave is fairly simple using the Pattern Stamp Tool. Sample an piece of your image with your Marquee Tool, shortcut key . Navigate to Edit > Define Pattern to create a new Pattern from your selection. Click OK to continue. Click and hold down on the Clone Stamp tool in your Tools Panel until you can select the Pattern Stamp Tool. Pick your new pattern from the Options at the top of your screen, in the Options Panel. Then simply right click in your image in order to pick as soft a brush as possible to paint with. Paint into your image until your background is as smooth as you want it to be, making your painted out object more and more invisible. If you get lines from your repeated texture, experiment turning the on and off and paint over them. In addition to this, simple use of the Crop Tool, shortcut , can recompose an image, making it look as if it never had another object in it at all. Combine these techniques to find a method that works best for your images. Have questions or comments concerning Graphics, Photos, Filetypes, or Photoshop? Send your questions to [email protected], and they may be featured in a future How-To Geek Graphics article. Image Credits: Geisha Kyoto Gion by Todd Laracuenta via Wikipedia, used under Creative Commons. Moai Rano raraku by Aurbina, in Public Domain. Chris Young visits Wrigley by TonyTheTiger, via Wikipedia, used under Creative Commons. Latest Features How-To Geek ETC Ask How-To Geek: How Can I Monitor My Bandwidth Usage? Internet Explorer 9 RC Now Available: Here’s the Most Interesting New Stuff Here’s a Super Simple Trick to Defeating Fake Anti-Virus Malware How to Change the Default Application for Android Tasks Stop Believing TV’s Lies: The Real Truth About "Enhancing" Images The How-To Geek Valentine’s Day Gift Guide CyanogenMod Updates; Rolls out Android 2.3 to the Less Fortunate MyPaint is an Open-Source Graphics App for Digital Painters Can the Birds and Pigs Really Be Friends in the End? [Angry Birds Video] Add the 2D Version of the New Unity Interface to Ubuntu 10.10 and 11.04 MightyMintyBoost Is a 3-in-1 Gadget Charger Watson Ties Against Human Jeopardy Opponents

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  • Coordinates from 3DS Max to XNA 3.5

    - by David Conde
    Hello My problem is this. I have a simple box made in 3DS Max 2009, the Box is 10x10x10. I've tried to load it on XNA and traslate the camera for 15 units, but I can seem to find the values needed to see the box properly. Can anyone point me to a good resource where I can find some good introduction to XNA coordinate system and how is a simple box made in 3DS Max imported properly Best regards, David

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  • 2D animation example in pyglet (python) looping through 2 images/sprites every x seconds

    - by Bentley4
    Suppose you have two images: step1.png and step2.png . Can anyone show me a very simple example in pyglet how to loop through those 2 images say every 0.5 seconds? The character doesn't have to move, just a simple black screen with a fixed region wherein the two images continually change every 0.5 secs. I know how to make a character move, shoot projectiles etc. but I just can't figure out how to control the looping speed of the images.

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  • Visio drawing in SharePoint 2007

    - by MartinIsti
    Yesterday I decided to improve a SharePoint site a bit by replacing the very basic navigation web part ( content editor web part with a 5x4 table that contains only text with hyperlinks and very far from being pretty) with something fancier. I decided to use Visio for that. I created a quite simple chart: Simple I admit, but much better than this one: Do you agree? ;o) I think I will make the visio drawing a bit fancier but the main point of this blog is how to publish it into a SharePoint site?...(read more)

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  • Silverlight hierarchy gridview with MVVM

    - by Suresh Behera
    Since few days i have been struggling to bind a gridview from a simple WCF async call. Following article look promising… http://blogs.telerik.com/vladimirenchev/posts/09-10-16/how_to_silverlight_grid_hierarchy_load_on_demand_using_mvvm_and_ria_services.aspx I conclude binding is not simple traditional databind() method call from gridview if you don’t know howto ;) Thanks, Suresh...(read more)

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  • Introducing the New Face of Fusion Applications

    - by mvaughan
    By Misha Vaughan and Kathy Miedema, Oracle Applications User Experience At OpenWorld 2012, the Oracle Applications User Experience (UX) team unveiled the new face of Fusion Applications. You may have seen it in sessions presented by Chris Leone, Anthony Lye, Jeremy Ashley or others, or you may have gotten a look on the demogrounds. This screenshot shows the new Oracle Fusion Applications entry experience.Why are we delivering a new face for Fusion Applications? Because, says Ashley, the vice president of the Oracle Applications User Experience team, we want to provide a simple, modern, productive way for users to complete their top quick-entry tasks. The idea is to provide a clear, productive user experience that is backed by the full functionality of Fusion Applications. The first release of the new face of Fusion focuses on three types of users. It provides a fully functional gateway to Fusion Applications for: New and casual users who need quick access to self-service tasks Professional users who need fast access to quick-entry, high-volume tasks Users who are looking for a way to quickly brand their portal for employees The new face of Fusion allows users to move easily from navigation to action, Ashley said, and it has been designed for any device -- Mac, PC, iPad, Android, SmartBoard -- in the browser. The Oracle Fusion Applications Employee Directory. How did we build it? The new face of Fusion essentially is a custom shell, developed by the Apps UX team, and a set of page templates that embodies a simple design aesthetic. It’s repeatable, providing consistency across its pages, and requires little to zero training. More specifically, the new face of Fusion has been built on ADF. The Applications UX team created pages in JDeveloper using local tasks flows bound to existing view objects. Three new components were commissioned from ADF, and existing Fusion components were re-skinned to deliver a simple, modern user experience. It really is that simple – and to prove that point, we’ve been sharing our story around the new face of Fusion on several Oracle channels such as this one. Want to know more? Check the VoX blog for our favorite highlights from OpenWorld, which included demos of the new face of Fusion. And take a look at these posts from Ace Directors Debra Lilley, and Floyd Teter. Special mention to Floyd for the first screen shot credit. Also a nod to Wilfred vander Deijl for capturing the demo to share as part 1 and part 2. We will also be hitting upcoming user group conferences with our demos, and you can always reach out to one of our Fusion User Experience Advocates for a look.

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  • New Pluralsight Course: HTML5 Canvas Fundamentals

    - by dwahlin
      I just finished up a new course for Pluralsight titled HTML5 Canvas Fundamentals that I had a blast putting together. It’s all about the client and involves a lot of pixel manipulation and graphics creation which is challenging and fun at the same time. The goal of the course is to walk you through the fundamentals, start a gradual jog into the API functions, and then start sprinting as you learn how to build a business chart canvas application from scratch that uses many of the available APIs . It’s fun stuff and very useful in a variety of scenarios including Web (desktop or mobile) and even Windows 8 Metro applications. Here’s a sample video from the course that talks about building a simple bar chart using the HTML5 Canvas:   Additional details about the course are shown next.   HTML5 Canvas Fundamentals The HTML5 Canvas provides a powerful way to render graphics, charts, and other types of visual data without relying on plugins such as Flash or Silverlight. In this course you’ll be introduced to key features available in the canvas API and see how they can be used to render shapes, text, video, images, and more. You’ll also learn how to work with gradients, perform animations, transform shapes, and build a custom charting application from scratch. If you’re looking to learn more about using the HTML5 Canvas in your Web applications then this course will break down the learning curve and give you a great start!    Getting Started with the HTML5 Canvas Introduction HTML5 Canvas Usage Scenarios Demo: Game Demos Demo: Engaging Applications Demo: Charting HTML5 Canvas Fundamentals Hello World Demo Overview of the Canvas API Demo: Canvas API Documentation Summary    Drawing with the HTML5 Canvas Introduction Drawing Rectangles and Ellipses Demo: Simple Bar Chart Demo: Simple Bar Chart with Transforms Demo: Drawing Circles Demo: Using arcTo() Drawing Lines and Paths Demo: Drawing Lines Demo: Simple Line Chart Demo: Using bezierCurveTo() Demo: Using quadraticCurveTo() Drawing Text Demo: Filling, Stroking, and Measuring Text Demo: Using Canvas Transforms with Text Drawing Images Demo: Using Image Functions Drawing Videos Demo: Syncing Video with a Canvas Summary    Manipulating Pixels  Introduction Rendering Gradients Demo: Creating Linear Gradients Demo: Creating Radial Gradients Using Transforms Demo: Getting Started with Transform Functions Demo: Using transform() and and setTransform() Accessing Pixels Demo: Creating Pixels Dynamically Demo: Grayscale Pixels Animation Fundamentals Demo: Getting Started with Animation Demo: Using Gradients, Transforms, and Animations Summary    Building a Custom Data Chart Introduction Creating the CanvasChart Object Creating the CanvasChart Shell Code Rendering Text and Gradients Rendering Data Points Text and Guide Lines Connecting Data Point Lines Rendering Data Points Adding Animation Adding Overlays and Interactivity Summary     Related Courses:  

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  • Fun with Declarative Components

    - by [email protected]
    Use case background I have been asked on a number of occasions if our selectOneChoice component could allow random text to be entered, as well as having a list of selections available. Unfortunately, the selectOneChoice component only allows entry via the dropdown selection list and doesn't allow text entry. I was thinking of possible solutions and thought that this might make a good example for using a declarative component.My initial idea My first thought was to use an af:inputText to allow the text entry, and an af:selectOneChoice with mode="compact" for the selections. To get it to layout horizontally, we would want to use an af:panelGroupLayout with layout="horizontal". To get the label for this to line up correctly, we'll need to wrap the af:panelGroupLayout with an af:panelLabelAndMessage. This is the basic structure: <af:panelLabelAndMessage> <af:panelGroupLayout layout="horizontal"> <af:inputText/> <af:selectOneChoice mode="compact"/> </af:panelgroupLayout></af:panelLabelAndMessage> Make it into a declarative component One of the steps to making a declarative component is deciding what attributes we want to be able to specify. To keep this example simple, let's just have: 'label' (the label of our declarative component)'value' (what we want to bind to the value of the input text)'items' (the select items in our dropdown) Here is the initial declarative component code (saved as file "inputTextWithChoice.jsff"): <?xml version='1.0' encoding='UTF-8'?><!-- Copyright (c) 2008, Oracle and/or its affiliates. All rights reserved. --><jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1" xmlns:f="http://java.sun.com/jsf/core" xmlns:af="http://xmlns.oracle.com/adf/faces/rich"> <jsp:directive.page contentType="text/html;charset=utf-8"/> <af:componentDef var="attrs" componentVar="comp"> <af:xmlContent> <component xmlns="http://xmlns.oracle.com/adf/faces/rich/component"> <description>Input text with choice component.</description> <attribute> <description>Label</description> <attribute-name>label</attribute-name> <attribute-class>java.lang.String</attribute-class> </attribute> <attribute> <description>Value</description> <attribute-name>value</attribute-name> <attribute-class>java.lang.Object</attribute-class> </attribute> <attribute> <description>Choice Select Items Value</description> <attribute-name>items</attribute-name> <attribute-class>[[Ljavax.faces.model.SelectItem;</attribute-class> </attribute> </component> </af:xmlContent> <af:panelLabelAndMessage id="myPlm" label="#{attrs.label}" for="myIt"> <af:panelGroupLayout id="myPgl" layout="horizontal"> <af:inputText id="myIt" value="#{attrs.value}" partialTriggers="mySoc" label="myIt" simple="true" /> <af:selectOneChoice id="mySoc" label="mySoc" simple="true" mode="compact" value="#{attrs.value}" autoSubmit="true"> <f:selectItems id="mySIs" value="#{attrs.items}" /> </af:selectOneChoice> </af:panelGroupLayout> </af:panelLabelAndMessage> </af:componentDef></jsp:root> By having af:inputText and af:selectOneChoice both have the same value, then (assuming that this passed in as an EL expression) selecting something in the selectOneChoice will update the value in the af:inputText. To use this declarative component in a jspx page: <af:declarativeComponent id="myItwc" viewId="inputTextWithChoice.jsff" label="InputText with Choice" value="#{demoInput.choiceValue}" items="#{demoInput.selectItems}" /> Some problems arise At first glace, this seems to be functioning like we want it to. However, there is a side effect to having the af:inputText and af:selectOneChoice share a value, if one changes, so does the other. The problem here is that when we update the af:inputText to something that doesn't match one of the selections in the af:selectOneChoice, the af:selectOneChoice will set itself to null (since the value doesn't match one of the selections) and the next time the page is submitted, it will submit the null value and the af:inputText will be empty. Oops, we don't want that. Hmm, what to do. Okay, how about if we make sure that the current value is always available in the selection list. But, lets not render it if the value is empty. We also need to add a partialTriggers attribute so that this gets updated when the af:inputText is changed. Plus, we really don't want to select this item so let's disable it. <af:selectOneChoice id="mySoc" partialTriggers="myIt" label="mySoc" simple="true" mode="compact" value="#{attrs.value}" autoSubmit="true"> <af:selectItem id="mySI" label="Selected:#{attrs.value}" value="#{attrs.value}" disabled="true" rendered="#{!empty attrs.value}"/> <af:separator id="mySp" /> <f:selectItems id="mySIs" value="#{attrs.items}" /></af:selectOneChoice> That seems to be working pretty good. One minor issue that we probably can't do anything about is that when you enter something in the inputText and then click on the selectOneChoice, the popup is displayed, but then goes away because it has been replaced via PPR because we told it to with the partialTriggers="myIt". This is not that big a deal, since if you are entering something manually, you probably don't want to select something from the list right afterwards. Making it look like a single component. Now, let's play around a bit with the contentStyle of the af:inputText and the af:selectOneChoice so that the compact icon will layout inside the af:inputText, making it look more like an af:selectManyChoice. We need to add some padding-right to the af;inputText so there is space for the icon. These adjustments were for the Fusion FX skin. <af:inputText id="myIt" partialTriggers="mySoc" autoSubmit="true" contentStyle="padding-right: 15px;" value="#{attrs.value}" label="myIt" simple="true" /><af:selectOneChoice id="mySoc" partialTriggers="myIt" contentStyle="position: relative; top: -2px; left: -19px;" label="mySoc" simple="true" mode="compact" value="#{attrs.value}" autoSubmit="true"> <af:selectItem id="mySI" label="Selected:#{attrs.value}" value="#{attrs.value}" disabled="true" rendered="#{!empty attrs.value}"/> <af:separator id="mySp" /> <f:selectItems id="mySIs" value="#{attrs.items}" /></af:selectOneChoice> There you have it, a declarative component that allows for suggested selections, but also allows arbitrary text to be entered. This could be used for search field, where the 'items' attribute could be populated with popular searches. Lines of java code written: 0

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  • Slick2d/Nifty-gui input

    - by eerongal
    I'm trying to get input from slick2d into nifty gui. Ive searched online, and I've seen a few examples, but I can't seem to get it working right. i've tried the example on here but I can't seem to get everything working. I'm not entirely sure what I'm doing wrong. I've also looked at examples using the JMonkeyEngine to help point me in the right direction, but still having issues with input. I can get everything else working like i need. Here's the code for my element controller: package gui; import java.util.Properties; import de.lessvoid.nifty.Nifty; import de.lessvoid.nifty.controls.Controller; import de.lessvoid.nifty.elements.Element; import de.lessvoid.nifty.input.NiftyInputEvent; import de.lessvoid.nifty.screen.Screen; import de.lessvoid.xml.xpp3.Attributes; public class BaseElementController implements Controller { private Element element; public void bind(Nifty arg0, Screen arg1, Element arg2, Properties arg3, Attributes arg4) { this.element = element; } public void init(Properties arg0, Attributes arg1) { // TODO Auto-generated method stub } public boolean inputEvent(NiftyInputEvent arg0) { // TODO Auto-generated method stub return false; } public void onFocus(boolean arg0) { // TODO Auto-generated method stub } public void onStartScreen() { // TODO Auto-generated method stub } public void test() { System.out.println("test"); } public void bam() { System.out.println("bam"); } } Here's my XML file: <?xml version="1.0" encoding="UTF-8" standalone="no"?> <nifty> <useStyles filename="nifty-default-styles.xml"/> <useControls filename="nifty-default-controls.xml"/> <screen id="screen2" controller="gui.BaseScreenController"> <layer backgroundColor="#fff0" childLayout="absolute" id="layer4" controller="gui.BaseElementController"> <panel childLayout="center" height="30%" id="panel1" style="nifty-panel-simple" width="50%" x="282" y="334" controller="gui.BaseElementController"> <control id="checkbox1" name="checkbox"/> <control childLayout="center" id="button2" label="button2" name="button" x="381" y="224" visibleToMouse="true" controller="gui.BaseElementController"> <interact onClick="bam()"/> </control> </panel> <text text="${CALL.getPlayerName()}" style="nifty-label" width="100%" height="100%" x="0" y="10" /> </layer> </screen> </nifty> Here's how I'm trying to bind the controller: public void init(GameContainer gc) throws SlickException { Input input = gc.getInput(); inputSystem = new PlainSlickInputSystem(); inputSystem.setInput(input); gui = new Gui(); gui.init(gc, inputSystem, "gui/tset.xml", "screen2"); input.removeListener(this); input.removeListener(inputSystem); input.addListener(inputSystem); } Essentially, all that happens right now is the screen loads up and displays, and it grabs the variable correctly in the label, but none of the input seems to be getting forwarded to Nifty from slick. I assume there's something I'm missing, but I can't seem to figure out what that is. In so far as what I have tried, I attempted to define a custom input listener to pick up events and assign that to my game in order to pick up input, which did not work, so i dropped that implementation, at current i'm trying to take the default inputs and bind then with a PlainSlickInputSystem and assigning that to the input (as shown in the first example link). On code execution, all the code is hit, and i've put several system.out.println's to get ouput of what is happening (the code above has been cleaned for presentation), and i even see the elements getting bound to the controller, yet it doesn't pick up controller events. As far as EXACTLY what's wrong, that I don't know, because I've followed all implementations i can find of this, and none of them seem to do anything it's like the input is just getting thrown out. None of the objects from niftyGui appear to be recognizing any input. Here is the binding from my objects at run time: ******INITIALIZED SCREEN: de.lessvoid.nifty.screen.Screen@4a1ab1c1 ******INITIALIZED ELEMENT: button2 (de.lessvoid.nifty.elements.Element@1e8c1be9) ******INITIALIZED ELEMENT: focusable => true, width => 100px {nifty-button#panel}, backgroundImage => button/button.png {nifty-button#panel}, label => button2, paddingLeft => 7px {nifty-button#panel}, imageMode => sprite-resize:100,23,0,2,96,2,2,2,96,2,19,2,96,2,2 {nifty-button#panel}, paddingRight => 7px {nifty-button#panel}, id => button2, visibleToMouse => true, height => 23px {nifty-button#panel}, style => nifty-button, name => button, inputMapping => de.lessvoid.nifty.input.mapping.MenuInputMapping, childLayout => center, controller => gui.BaseElementController, y => 224, x => 381 ******INITIALIZED SCREEN: de.lessvoid.nifty.screen.Screen@4a1ab1c1 ******INITIALIZED ELEMENT: panel1 (de.lessvoid.nifty.elements.Element@373ec894) ******INITIALIZED ELEMENT: id => panel1, height => 30%, style => nifty-panel-simple, width => 50%, backgroundImage => panel/nifty-panel-simple.png {nifty-panel-simple}, controller => gui.BaseElementController, childLayout => center, padding => 5px {nifty-panel-simple}, imageMode => resize:9,2,9,9,9,2,9,2,9,2,9,9 {nifty-panel-simple}, y => 334, x => 282 ******INITIALIZED SCREEN: de.lessvoid.nifty.screen.Screen@4a1ab1c1 ******INITIALIZED ELEMENT: layer4 (de.lessvoid.nifty.elements.Element@6427d489) ******INITIALIZED ELEMENT: id => layer4, backgroundColor => #fff0, controller => gui.BaseElementController, childLayout => absolute the button2 object is getting bound to my BaseElementController, but i can't seem to get it into the defined "onClick" call.

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  • How Parallelism Works in SQL Server

    - by Paul White
    You might have noticed that January was a quiet blogging month for me.  Part of the reason was that I was working on a series of articles for Simple Talk, examining how parallel query execution really works.  The first part is published today at: http://www.simple-talk.com/sql/learn-sql-server/understanding-and-using-parallelism-in-sql-server/ . This introductory piece is not quite as deeply technical as my SQLblog posts tend to be, but I hope there be enough interesting material to make...(read more)

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  • SQL SERVER – Creating All New Database with Full Recovery Model

    - by pinaldave
    Sometimes, complex problems have very simple solutions. Let us see the following email which I received recently. “Hi Pinal, In our system when we create new database, by default, they are all created with the Simple Recovery Model. We have to manually change the recovery model after we create the database. We used the following simple T-SQL code: CREATE DATABASE dbname. We are very frustrated with this situation. We want all our databases to have the Full Recovery Model option by default. We are considering the following methods; please suggest the most efficient one among them. 1) Creating a Policy; when it is violated, the database model can be fixed 2) Triggers at Server Level 3) Automated Job which goes through all the databases and checks their recovery model; if the DBA has not changed the model, then the job will list the Databases and change their recovery model Also, we have a situation where we need a database in the Simple Recovery Model as well – how to white list them? Please suggest the best method.” Indeed, an interesting email! The answer to their question, i.e., which is the best method to fit their needs (white list, default, etc)? It will be NONE of the above. Here is the solution in one line and also the easiest way: Just go to your Model database: Path in SSMS >> Databases > System Databases >> model >> Right Click Properties >> Options >> Recovery Model - Select Full from dropdown. Every newly created database takes its base template from the Model Database. If you create a custom SP in the Model Database, when you create a new database, it will automatically exist in that database. Any database that was already created before making changes in the Model Database will not be affected at all. Creating Policy is also a good method, and I will blog about this in a separate blog post, but looking at current specifications of the reader, I think the Model Database should be modified to have a Full Recovery Option. While writing this blog post, I remembered my another blog post where the model database log file was growing drastically even though there were no transactions SQL SERVER – Log File Growing for Model Database – model Database Log File Grew Too Big. NOTE: Please do not touch the Model Database unnecessary. It is a strict “No.” If you want to create an object that you need in all the databases, then instead of creating it in model database, I suggest that you create a new database called maintenance and create the object there. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, Readers Question, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Python class representation under the hood

    - by decentralised
    OK, here is a simple Python class: class AddSomething(object): __metaclass__ = MyMetaClass x = 10 def __init__(self, a): self.a = a def add(self, a, b): return a + b We have specified a metaclass, and that means we could write something like this: class MyMetaClass(type): def __init__(cls, name, bases, cdict): # do something with the class Now, the cdict holds a representation of AddSomething: AddSomething = type('AddSomething', (object,), {'x' : 10, '__init__': __init__, 'add': add}) So my question is simple, are all Python classes represented in this second format internally? If not, how are they represented? EDIT - Python 2.7

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  • Big Visible Charts

    - by Robert May
    An important part of Agile is the concept of transparency and visibility. In proper functioning teams, stakeholders can look at any team at any time in the iteration or release and see how that team is doing by simply looking at what we call Big Visible Charts. If you’ve done Scrum, you’ve seen these charts. However, interpreting these charts can often be an art form. There are several different charts that can be useful. In this newsletter, I’ll focus on the Iteration Burndown and Cumulative Flow charts. I’ve included a copy of the spreadsheet that I used to create the charts, and if you don’t have a tool that creates them for you, you can use this spreadsheet to do so. Our preferred tool for managing Scrum projects is Rally. Rally creates all of these charts for you, saving you quite a bit of time. The Iteration Burndown and Cumulative Flow Charts This is the main chart that teams use. Although less useful to stakeholders, this chart is critical to the team and provides quite a bit of information to the team about how their iteration is going. Most charts are a combination of the charts below, so you may need to combine aspects of each section to understand what is happening in your iterations. Ideal Ah, isn’t that a pretty picture? Unfortunately, it’s also very unrealistic. I’ve seen iterations that come close to ideal, but never that match perfectly. If your iteration matches perfectly, chances are, someone is playing with the numbers. Reality is just too difficult to have a burndown chart that matches this exactly. Late Planning Iteration started, but the team didn’t. You can tell this by the fact that the real number of estimated hours didn’t appear until day two. In the cumulative flow, you can also see that nothing was defined in Day one and two. You want to avoid situations like this. You’ll note that the team had to burn faster than is ideal to meet the iteration because of the late planning. This often results in long weeks and days. Testing Starved Determining whether or not testing is starved is difficult without the cumulative flow. The pattern in the burndown could be nothing more that developers not completing stories early enough or could be caused by stories being too big. With the cumulative flow, however, you see that only small bites are in progress and stories were completed early, but testing didn’t start testing until the end of the iteration, and didn’t complete testing all stories in the iteration. When this happens, question whether or not your testing resources are sufficient for your team and whether or not acceptance is adequately defined. No Testing With this one, both graphs show the same thing; the team needs testers and testing! Without testing, what was completed cannot be verified to make sure that it is acceptable to the business. If you find yourself in this situation, review your testing practices and acceptance testing process and make changes today. Late Development With this situation, both graphs tell a story. In the top graph, you can see that the hours failed to burn down as quickly as the team expected. This could be caused by the team not correctly estimating their hours or the team could have had illness or some other issue that affected them. Often, when teams are tackling something that is more unknown, they’ll run into technical barriers that cause the burn down to happen slower than expected. In the cumulative flow graph, you can see that not much was completed in the first few days. This could be because of illness or technical barriers or simply poor estimation. Testing was able to keep up with everything that was completed, however. No Tool Updating When you see graphs that look like this, you can be assured that it’s because the team is not updating the tool that generates the graphs. Review your policy for when they are to update. On the teams that I run, I require that each team member updates the tool at least once daily. You should also check to see how well the team is breaking down stories into tasks. If they’re creating few large tasks, graphs can look similar to this. As a general rule, I never allow tasks, other than Unit Testing and Uncertainty, to be greater than eight hours in duration. Scope Increase I always encourage team members to enter in however much time they think they have left on a task, even if that means increasing the total amount of time left to do. You get a much better and more realistic picture this way. Increasing time remaining could explain the burndown graph, but by looking at the cumulative flow graph, we can see that stories were added to the iteration and scope was increased. Since planning should consume all of the hours in the iteration, this is almost always a bad thing. If the scope change happened late in the iteration and the hours remaining were well below the ideal burn, then increasing scope is probably o.k., but estimation needs to get better. However, with the charts above, that’s clearly not what happened and the team was required to do extra work to make the iteration. If you find this happening, your product owner and ScrumMasters need training. The team also needs to learn to say no. Scope Decrease Scope decreases are just as bad as scope increases. Usually, graphs above show that the team did a poor job of estimating their stories and part way through had to reduce scope to change the iteration. This will happen once in a while, but if you find it’s a pattern on your team, you need to re-evaluate planning. Some teams are hopelessly optimistic. In those cases, I’ll introduce a task I call “Uncertainty.” With Uncertainty, the team estimates how many hours they might need if things don’t go well with the tasks they’ve defined. They try to estimate things that could go poorly and increase the time appropriately. Having an Uncertainty task allows them to have a low and high estimate. Uncertainty should not just be an arbitrary buffer. It must correlate to real uncertainty in the tasks that have been defined. Stories are too Big Often, we see graphs like the ones above. Note that the burndown looks fairly good, other than the chunky acceptance of stories. However, when you look at cumulative flow, you can see that at one point, everything is in progress. This is a bad thing. When you see graphs like this, you’re in one of two states. You may just have a very small team and can only handle one or two stories in your iteration. If you have more than one or two people, then the most likely problem is that your stories are far too big. To combat this, break large high hour stories into smaller pieces that can be completed independently and accepted independently. If you don’t, you’ll likely be requiring your testers to do heroic things to complete testing on the last day of the iteration and you’re much more likely to have the entire iteration fail, because of the limited amount of things that can be completed. Summary There are other charts that can be useful when doing scrum. If you don’t have any big visible charts, you really need to evaluate your process and change. These charts can provide the team a wealth of information and help you write better software. If you have any questions about charts that you’re seeing on your team, contact me with a screen capture of the charts and I’ll tell you what I’m seeing in those charts. I always want this information to be useful, so please let me know if you have other questions. Technorati Tags: Agile

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  • ASP.NET Horizontal Menu Control

    A few weeks ago, I was working on an ASP.NET web application and needed a simple horizontal menu with a submenu. I decided to use ASP.NET's Menu control: Just drag and drop the control on to the page. Simple enough, but the control did not provide access key and target window support on menu items. I have put together a tutorial on how to include an access key attribute, include a target attribute, and include a site map path.

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  • Remove files from Bazaar

    - by Kristopher Ives
    I'm using Bazaar (bzr) to keep source code for a website updated, but we've ran into a problem when we remove files from version control. The files we are removing are ones we never intended to version to begin with. When this happens we use bzr rm --keep to remove the file from version control, but keep the file in the file system. Doing a bzr push or bzr pull results in the removed file(s) being removed on the other branches (other sites that use our code) We need a way to make sure that a bzr push or bzr pull doesn't actually remove those from the working copy. Anyone have any ideas?

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  • How to exercise and feel well when programming?

    - by Filip Ekberg
    While I'm sitting here in my expensive chair which was told to me were gonna help me with my neck and shoulder pains; it didn't. So don't go spend $2,000 on a chair because it's not gonna help. I am trying everything to keep my body in shape, exercising to keep my pizza-body slim and just to feel well in general. What I'd like to do is take a couple of seconds, maybe when the code compiles, to reach up, do a couple of X and feel good. But, what is this X? When I sit there at work, what will everyone think when I stand up and start to hula hula because I want to exercise my basin? I know a lot of programmers out there do have pain so let's come up with a little list together to help us all keep our joints feeling good. Programming gives me joint pain, how do i avoid it without quitting programming?

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  • Algorithm to generate multifaced cube?

    - by OnePie
    Are there any elegant soloution to generate a simple-six sided cube, where each cube is made out of more than one face? The method I have used ended up a horrible and complicated mess of logic that is imopssible to follow and most likely to maintain. The algorithm should not generate reduntant vertices, and should output the indice list for the mesh as well. The reason I need this is that the cubes vertices will be deformed depending on various factors, meaning that a simple six-faced cube will nto do.

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  • The 20 Most Important Keyboard Shortcuts For Windows PCs

    - by Chris Hoffman
    Keyboard shortcuts are practically essential for using any type of PC. They’ll speed up almost everything you do. But long lists of keyboard shortcuts can quickly become overwhelming if you’re just getting started. This list will cover the most useful keyboard shortcuts that every Windows user should know. If you haven’t used keyboard shortcuts much, these will show you just how useful keyboard shortcuts can be. Windows Key + Search The Windows key is particularly important on Windows 8 — especially before Windows 8.1 — because it allows you to quickly return to the Start screen. On Windows 7, it opens the Start menu. Either way, you can start typing immediately after you press the Windows key to search for programs, settings, and files. For example, if you want to launch Firefox, you can press the Windows key, start typing the word Firefox, and press Enter when the Firefox shortcut appears. It’s a quick way to launch programs, open files, and locate Control Panel options without even touching your mouse and without digging through a cluttered Start menu. You can also use the arrow keys to select the shortcut you want to launch before pressing Enter. Copy, Cut, Paste Copy, Cut, and Paste are extremely important keyboard shortcuts for text-editing. If you do any typing on your computer, you probably use them. These options can be accessed using the mouse, either by right-clicking on selected text or opening the application’s Edit menu, but this is the slowest way to do it. After selecting some text, press Ctrl+C to copy it or Ctrl+X to cut it. Position the cursor where you want the text and use Ctrl+V to paste it. These shortcuts can save you a huge amount of time over using the mouse. Search the Current Page or File To quickly perform a search in the current application — whether you’re in a web browser, PDF viewer, document editor, or almost any other type of application — press Ctrl+F. The application’s search (or “Find”) feature will pop up, and you can instantly start typing a phrase you want to search for. You can generally press Enter to  go to the next appearance of the word or phrase in the document, quickly searching through it for what you’re interested in. Switch Between Applications and Tabs Rather than clicking buttons on your taskbar, Alt+Tab is a very quick way to switch between running applications. Windows orders the list of open windows by the order you accessed them, so if you’re only using two different applications, you can just press Alt+Tab to quickly switch between them. If switching between more than two windows, you’ll have to hold the Alt key and press Tab repeatedly to toggle through the list of open windows. If you miss the window you want, you can always press Alt+Shift+Tab to move through the list in reverse. To move between tabs in an application — such as the browser tabs in your web browser — press Ctrl+Tab. Ctrl+Shift+Tab will move through tabs in reverse. Quickly Print If you’re the kind of person who still prints things, you can quickly open the print window by pressing Ctrl+P. This can be faster than hunting down the Print option in every program you want to print something from. Basic Browser Shortcuts Web browser shortcuts can save you tons of time, too. Ctrl+T is a very useful one, as it will open a new tab with the address bar focused, so you can quickly press Ctrl +T, type a search phrase or web address, and press Enter to go there. To go back or forward while browsing, hold the Ctrl key and press the left or right arrow keys. If you’d just like to focus your web browser’s address bar so you can type a new web address or search without opening a new tab, press Ctrl + L. You can then start typing something and press Enter. Close Tabs and Windows To quickly close the current application, press Alt+F4. This works on the desktop and even in new Windows 8-style applications. To quickly close the current browser tab or document, press Ctrl+W. This will often close the current window if there are no other tabs open. Lock Your Computer When you’re done using your computer and want to step away, you may want to lock it. People won’t be able to log in and access your desktop unless they know your password. You can do this from the Start menu or Start screen, but the fastest way to lock your screen is by quickly pressing Windows Key + L before you get up. Access the Task Manager Ctrl+Alt+Delete will take you to a screen that allows you to quickly launch the Task Manager or perform other operations, such as signing out. This is particularly useful because if can be used to recover from situations where your computer doesn’t appear responsive or isn’t accepting input. For example, if a full-screen game becomes unresponsive, Ctrl+Alt+Delete will often allow you to escape from it and end it via the Task Manager. Windows 8 Shortcuts On Windows 8 PCs, there are other very important keyboard shortcuts. Windows Key + C will open your Charms bar, while Windows Key + Tab will open the new App Switcher. These keyboard shortcuts will allow you to avoid the hot corners, which can be tedious to use with a mouse. On the desktop side, Windows Key + D will take you back to the desktop from anywhere. Windows Key + X will open a special “power user menu” that gives you quick access to options that are hidden in the new Windows 8 interface, including Shut Down, Restart, and Control Panel. If you’re interested in learning more keyboard shortcuts, be sure to check our longer lists of 47 keyboard shortcuts that work in all web browsers and 42+ keyboard shortcuts to speed up text-editing. Image Credit: Jeroen Bennink on Flickr     

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  • What is the best way to manage one's session variables?

    - by donde
    In my .NET web app, I keep basic user info in a user session object. I also usually keep a director class in the session; which is basically just has info about whatever thing it being worked on on that screen (like a customer id). I am trying to keep from adding a ton of sessions. I also want to make sure at any given time ONLY the sessions that are necessary are in memory. This means I need an effective way of managing my session variables. Any suggestions?

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  • Profiling Startup Of VS2012 &ndash; SpeedTrace Profiler

    - by Alois Kraus
    SpeedTrace is a relatively unknown profiler made a company called Ipcas. A single professional license does cost 449€+VAT. For the test I did use SpeedTrace 4.5 which is currently Beta. Although it is cheaper than dotTrace it has by far the most options to influence how profiling does work. First you need to create a tracing project which does configure tracing for one process type. You can start the application directly from the profiler or (much more interesting) it does attach to a specific process when it is started. For this you need to check “Trace the specified …” radio button and enter the process name in the “Process Name of the Trace” edit box. You can even selectively enable tracing for processes with a specific command line. Then you need to activate the trace project by pressing the Activate Project button and you are ready to start VS as usual. If you want to profile the next 10 VS instances that you start you can set the Number of Processes counter to e.g. 10. This is immensely helpful if you are trying to profile only the next 5 started processes. As you can see there are many more tabs which do allow to influence tracing in a much more sophisticated way. SpeedTrace is the only profiler which does not rely entirely on the profiling Api of .NET. Instead it does modify the IL code (instrumentation on the fly) to write tracing information to disc which can later be analyzed. This approach is not only very fast but it does give you unprecedented analysis capabilities. Once the traces are collected they do show up in your workspace where you can open the trace viewer. I do skip the other windows because this view is by far the most useful one. You can sort the methods not only by Wall Clock time but also by CPU consumption and wait time which none of the other products support in their views at the same time. If you want to optimize for CPU consumption sort by CPU time. If you want to find out where most time is spent you need Clock Total time and Clock Waiting. There you can directly see if the method did take long because it did wait on something or it did really execute stuff that did take so long. Once you have found a method you want to drill deeper you can double click on a method to get to the Caller/Callee view which is similar to the JetBrains Method Grid view. But this time you do see much more. In the middle is the clicked method. Above are the methods that call you and below are the methods that you do directly call. Normally you would then start digging deeper to find the end of the chain where the slow method worth optimizing is located. But there is a shortcut. You can press the magic   button to calculate the aggregation of all called methods. This is displayed in the lower left window where you can see each method call and how long it did take. There you can also sort to see if this call stack does only contain methods (e.g. WCF connect calls which you cannot make faster) not worth optimizing. YourKit has a similar feature where it is called Callees List. In the Functions tab you have in the context menu also many other useful analysis options One really outstanding feature is the View Call History Drilldown. When you select this one you get not a sum of all method invocations but a list with the duration of each method call. This is not surprising since SpeedTrace does use tracing to get its timings. There you can get many useful graphs how this method did behave over time. Did it become slower at some point in time or was only the first call slow? The diagrams and the list will tell you that. That is all fine but what should I do when one method call was slow? I want to see from where it was coming from. No problem select the method in the list hit F10 and you get the call stack. This is a life saver if you e.g. search for serialization problems. Today Serializers are used everywhere. You want to find out from where the 5s XmlSerializer.Deserialize call did come from? Hit F10 and you get the call stack which did invoke the 5s Deserialize call. The CPU timeline tab is also useful to find out where long pauses or excessive CPU consumption did happen. Click in the graph to get the Thread Stacks window where you can get a quick overview what all threads were doing at this time. This does look like the Stack Traces feature in YourKit. Only this time you get the last called method first which helps to quickly see what all threads were executing at this moment. YourKit does generate a rather long list which can be hard to go through when you have many threads. The thread list in the middle does not give you call stacks or anything like that but you see which methods were found most often executing code by the profiler which is a good indication for methods consuming most CPU time. This does sound too good to be true? I have not told you the best part yet. The best thing about this profiler is the staff behind it. When I do see a crash or some other odd behavior I send a mail to Ipcas and I do get usually the next day a mail that the problem has been fixed and a download link to the new version. The guys at Ipcas are even so helpful to log in to your machine via a Citrix Client to help you to get started profiling your actual application you want to profile. After a 2h telco I was converted from a hater to a believer of this tool. The fast response time might also have something to do with the fact that they are actively working on 4.5 to get out of the door. But still the support is by far the best I have encountered so far. The only downside is that you should instrument your assemblies including the .NET Framework to get most accurate numbers. You can profile without doing it but then you will see very high JIT times in your process which can severely affect the correctness of the measured timings. If you do not care about exact numbers you can also enable in the main UI in the Data Trace tab logging of method arguments of primitive types. If you need to know what files at which times were opened by your application you can find it out without a debugger. Since SpeedTrace does read huge trace files in its reader you should perhaps use a 64 bit machine to be able to analyze bigger traces as well. The memory consumption of the trace reader is too high for my taste. But they did promise for the next version to come up with something much improved.

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  • Map building - Tower Defense

    - by Dan K
    Before diving too deep into my question, let it be known that I am learning as far as java script goes and figured a simple Tower Defense game would be an excellent way to learn things. So I have found a simple background image with a path drawn on it and my question is how would I go about building a path so that I can animate my objects. Would I have to take the image and overlay a grid system, or can I store the path in some sort of array and have my objects move across it? Here is the background image:

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  • JSP Precompilation for ADF Applications

    - by Duncan Mills
    A question that comes up from time to time, particularly in relation to build automation, is how to best pre-compile the .jspx and .jsff files in an ADF application. Thus ensuring that the app is ready to run as soon as it's installed into WebLogic. In the normal run of things, the first poor soul to hit a page pays the price and has to wait a little whilst the JSP is compiled into a servlet. Everyone else subsequently gets a free lunch. So it's a reasonable thing to want to do... Let Me List the Ways So forth to Google (other search engines are available)... which lead me to a fairly old article on WLDJ - Removing Performance Bottlenecks Through JSP Precompilation. Technololgy wise, it's somewhat out of date, but the one good point that it made is that it's really not very useful to try and use the precompile option in the weblogic.xml file. That's a really good observation - particularly if you're trying to integrate a pre-compile step into a Hudson Continuous Integration process. That same article mentioned an alternative approach for programmatic pre-compilation using weblogic.jspc. This seemed like a much more useful approach for a CI environment. However, weblogic.jspc is now obsoleted by weblogic.appc so we'll use that instead.  Thanks to Steve for the pointer there. And So To APPC APPC has documentation - always a great place to start, and supports usage both from Ant via the wlappc task and from the command line using the weblogic.appc command. In my testing I took the latter approach. Usage, as the documentation will show you, is superficially pretty simple.  The nice thing here, is that you can pass an existing EAR file (generated of course using OJDeploy) and that EAR will be updated in place with the freshly compiled servlet classes created from the JSPs. Appc takes care of all the unpacking, compiling and re-packing of the EAR for you. Neat.  So we're done right...? Not quite. The Devil is in the Detail  OK so I'm being overly dramatic but it's not all plain sailing, so here's a short guide to using weblogic.appc to compile a simple ADF application without pain.  Information You'll Need The following is based on the assumption that you have a stand-alone WLS install with the Application Development  Runtime installed and a suitable ADF enabled domain created. This could of course all be run off of a JDeveloper install as well 1. Your Weblogic home directory. Everything you need is relative to this so make a note.  In my case it's c:\builds\wls_ps4. 2. Next deploy your EAR as normal and have a peek inside it using your favourite zip management tool. First of all look at the weblogic-application.xml inside the EAR /META-INF directory. Have a look for any library references. Something like this: <library-ref>    <library-name>adf.oracle.domain</library-name> </library-ref>   Make a note of the library ref (adf.oracle.domain in this case) , you'll need that in a second. 3. Next open the nested WAR file within the EAR and then have a peek inside the weblogic.xml file in the /WEB-INF directory. Again  make a note of the library references. 4. Now start the WebLogic as per normal and run the WebLogic console app (e.g. http://localhost:7001/console). In the Domain Structure navigator, select Deployments. 5. For each of the libraries you noted down drill into the library definition and make a note of the .war, .ear or .jar that defines the library. For example, in my case adf.oracle.domain maps to "C:\ builds\ WLS_PS4\ oracle_common\ modules\ oracle. adf. model_11. 1. 1\ adf. oracle. domain. ear". Note the extra spaces that are salted throughout this string as it is displayed in the console - just to make it annoying, you'll have to strip these out. 6. Finally you'll need the location of the adfsharebean.jar. We need to pass this on the classpath for APPC so that the ADFConfigLifeCycleCallBack listener can be found. In a more complex app of your own you may need additional classpath entries as well.  Now we're ready to go, and it's a simple matter of applying the information we have gathered into the relevant command line arguments for the utility A Simple CMD File to Run APPC  Here's the stub .cmd file I'm using on Windows to run this. @echo offREM Stub weblogic.appc Runner setlocal set WLS_HOME=C:\builds\WLS_PS4 set ADF_LIB_ROOT=%WLS_HOME%\oracle_common\modulesset COMMON_LIB_ROOT=%WLS_HOME%\wlserver_10.3\common\deployable-libraries set ADF_WEBAPP=%ADF_LIB_ROOT%\oracle.adf.view_11.1.1\adf.oracle.domain.webapp.war set ADF_DOMAIN=%ADF_LIB_ROOT%\oracle.adf.model_11.1.1\adf.oracle.domain.ear set JSTL=%COMMON_LIB_ROOT%\jstl-1.2.war set JSF=%COMMON_LIB_ROOT%\jsf-1.2.war set ADF_SHARE=%ADF_LIB_ROOT%\oracle.adf.share_11.1.1\adfsharembean.jar REM Set up the WebLogic Environment so appc can be found call %WLS_HOME%\wlserver_10.3\server\bin\setWLSEnv.cmd CLS REM Now compile away!java weblogic.appc -verbose -library %ADF_WEBAPP%,%ADF_DOMAIN%,%JSTL%,%JSF% -classpath %ADF_SHARE% %1 endlocal Running the above on a target ADF .ear  file will zip through and create all of the relevant compiled classes inside your nested .war file in the \WEB-INF\classes\jsp_servlet\ directory (but don't take my word for it, run it and take a look!) And So... In the immortal words of  the Pet Shop Boys, Was It Worth It? Well, here's where you'll have to do your own testing. In  my case here, with a simple ADF application, pre-compilation shaved an non-scientific "3 Elephants" off of the initial page load time for the first access of each page. That's a pretty significant payback for such a simple step to add into your CI process, so why not give it a go.

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  • NUMA-aware placement of communication variables

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

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