Search Results

Search found 12089 results on 484 pages for 'rule of three'.

Page 119/484 | < Previous Page | 115 116 117 118 119 120 121 122 123 124 125 126  | Next Page >

  • how to keep same header on starting of next page in pdf

    - by Santosh Singh
    Here is My Code. private void getActionItems(Document document, Chapter chapter, Section section, Paragraph pas) { List drbRefList = null; try { _actionService = new ActionItemImpl(); _aiBean = new ActionItemData(); if (_aiBean != null) { _actionList = new ArrayList(); LOG.info("business passed here is" + _business); _actionList = _actionService.getActionItemsForPDF(_userSSOID, _business, _reviewID, _connection); } LOG.info(" after calling getActionItemsForPDF"); LOG.info("_actionList" + _actionList); Table tablesh1 = new Table(1, 1); float[] widthsh1 = new float[1]; widthsh1[0] = ReviewConstants.MAGIC_DOTTWELVE; tablesh1.setTableFitsPage(true); tablesh1.setPadding(2); tablesh1.setSpacing(0); tablesh1.setWidth(ReviewConstants.MAGIC_ONEZEROZERO); tablesh1.setWidths(widthsh1); tablesh1.setBorderColor(Color.WHITE); Cell hcell = new Cell(new Paragraph(ReviewConstants.S_ACTIONHEADING, new Font(Font.HELVETICA, fontSize, Font.BOLD, Color.BLUE))); hcell.setHeader(true); tablesh1.addCell(hcell); section.add(tablesh1); Table actionTable = null; String businessUnit = reviewData.getBusinessUnit(); float[] widthac = null; //Updated for Nuclear Energy Engineering Business Unit Requirement by Naveen if(!"Nuclear Energy Engineering".equalsIgnoreCase(businessUnit)){ actionTable = new Table(ReviewConstants.NINE,ReviewConstants.THREE); widthac = new float[ReviewConstants.NINE]; widthac[0] = ReviewConstants.MAGIC_DOTONE; widthac[1] = ReviewConstants.MAGIC_DOTONEZERO; widthac[2] = ReviewConstants.MAGIC_DOTTWOZERO; widthac[ReviewConstants.THREE] = ReviewConstants.MAGIC_DOTTWOZERO; widthac[ReviewConstants.FOUR] = ReviewConstants.MAGIC_DOTONEZERO; widthac[ReviewConstants.FIVE] = ReviewConstants.MAGIC_DOTONEZERO; widthac[ReviewConstants.SIX] = ReviewConstants.MAGIC_DOTONEZERO; widthac[ReviewConstants.SEVEN] = ReviewConstants.MAGIC_DOTONEZERO; widthac[ReviewConstants.EIGHT] = ReviewConstants.MAGIC_DOTONEZERO; }else{ actionTable = new Table(ReviewConstants.SIX,ReviewConstants.THREE); widthac = new float[ReviewConstants.SIX]; widthac[0] = ReviewConstants.MAGIC_DOTONE; widthac[1] = ReviewConstants.MAGIC_THREEZERO; widthac[2] = ReviewConstants.MAGIC_THREEZERO; widthac[ReviewConstants.THREE] = ReviewConstants.MAGIC_THREEZERO; widthac[ReviewConstants.FOUR] = ReviewConstants.MAGIC_DOTONEZERO; widthac[ReviewConstants.FIVE] = ReviewConstants.MAGIC_DOTONEZERO; } actionTable.setTableFitsPage(true); actionTable.setPadding(2); actionTable.setSpacing(0); actionTable.setWidth(ReviewConstants.MAGIC_ONEZEROZERO); actionTable.setWidths(widthac); actionTable.setBorderWidth(1); Cell accell = new Cell(new Paragraph(ReviewConstants.S_ACTIONID, new Font(Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); if(!"Nuclear Energy Engineering".equalsIgnoreCase(businessUnit)){ accell = new Cell(new Paragraph(ReviewConstants.PDF_RT, new Font(Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); } accell = new Cell(new Paragraph(ReviewConstants.S_REQA, new Font(Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); accell = new Cell(new Paragraph(ReviewConstants.S_CLOSURE, new Font(Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); accell = new Cell(new Paragraph(ReviewConstants.S_DISPOSITION, new Font(Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); //added by santosh on 18 june actionTable.endHeaders(); document.add(actionTable); if(!"Nuclear Energy Engineering".equalsIgnoreCase(businessUnit)){ accell = new Cell(new Paragraph(ReviewConstants.S_DRB_REFERENCE, new Font( Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); accell = new Cell(new Paragraph(ReviewConstants.S_DEADLINE, new Font( Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); } accell = new Cell(new Paragraph(ReviewConstants.S_OWNER, new Font( Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); accell = new Cell(new Paragraph(ReviewConstants.S_STATE, new Font( Font.HELVETICA, fontSize, Font.BOLD))); accell.setHeader(true); actionTable.addCell(accell); int acSize = 0; if (_actionList != null) { acSize = _actionList.size(); } for (int i = 0; i < acSize; i++) { _aiBean = (ActionItemData) _actionList.get(i); Cell adCell = new Cell(new Paragraph(_aiBean.getActionID(), new Font( Font.HELVETICA, ReviewConstants.MAGIC_EIGHT))); adCell.setHeader(false); actionTable.addCell(adCell); if(!"Nuclear Energy Engineering".equalsIgnoreCase(businessUnit)){ if (_aiBean.getActionItemType().equals("0")) { adCell = new Cell(new Paragraph("Normal", new Font(Font.HELVETICA, fontSize))); } else { adCell = new Cell(new Paragraph("Critical", new Font(Font.HELVETICA, fontSize))); } adCell.setHeader(false); actionTable.addCell(adCell); } adCell = new Cell(new Paragraph(_aiBean.getRequiredAction(), new Font(Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); adCell = new Cell(new Paragraph(_aiBean.getClosureCriteria(), new Font(Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); String drbLink = ReviewConstants.EMPTY; drbRefList = new ArrayList(); if (!DRUtils.isEmpty(_aiBean.getState()) && ((_aiBean.getState() .equalsIgnoreCase(ReviewConstants.DRAFT_BEGUN_STATE)) || (_aiBean.getState() .equalsIgnoreCase(ReviewConstants.SCOPE_PROPOSED)) || (_aiBean .getState() .equalsIgnoreCase(ReviewConstants.RES_PROPOSED)))) { drbLink = ReviewConstants.EMPTY; _aiBean.setDisposition(ReviewConstants.EMPTY); } else { drbRefList = _actionService.getDrbRefForPDF(_aiBean.getActionSeqID(), _connection); int drbRefCnt = 0; if (drbRefList != null) { drbRefCnt = drbRefList.size(); int j = 0; for (j = 0; j < drbRefCnt; j++) { LOG.info("drbRefList.get(j)" + drbRefList.get(j).toString()); if (j < (drbRefCnt - 1)) { drbLink += drbRefList.get(j).toString() + ReviewConstants.COMMA_SPACE; } else { drbLink += drbRefList.get(j).toString(); } } } } LOG.info("drbLink" + drbLink); adCell = new Cell(new Paragraph(_aiBean.getDisposition(), new Font(Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); //Updated for Nuclear Energy Engineering Business Unit Requirement by Naveen if(!"Nuclear Energy Engineering".equalsIgnoreCase(businessUnit)){ adCell = new Cell(new Paragraph(drbLink, new Font( Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); adCell = new Cell(new Paragraph(_aiBean.getDeadline(), new Font(Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); } adCell = new Cell(new Paragraph(_aiBean.getActionItemOwnerName(), new Font(Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); adCell = new Cell(new Paragraph(_aiBean.getState(), new Font(Font.HELVETICA, fontSize))); adCell.setHeader(false); actionTable.addCell(adCell); //added by santosh actionTable.endHeaders(); document.add(actionTable); // added by santosh end } /*Phrase headerPhrase = new Phrase(); Table headTab = (Table)actionTable.getElement(0, 5); headerPhrase.add(headTab); HeaderFooter printHeader = new HeaderFooter(headerPhrase,false); System.out.println("addHeader"); document.setHeader(printHeader); actionTable.setLastHeaderRow(1); actionTable.endHeaders(); document.add(actionTable);*/ // added by santosh actionTable.endHeaders(); document.add(actionTable); // added by santosh end section.add(actionTable); } catch (Exception e) { LOG.error("General Exception occured", e); } }

    Read the article

  • C Number to Text problem with ones and tens..

    - by Joegabb
    #include<stdio.h> #include<conio.h> main() { int ones,tens,ventoteen, myloop = 0; long num2,cents2,centeens,cents1,thousands,hundreds; double num; do{ printf("Enter a number: "); scanf("%lf",&num); if(num<=10000 || num>=0) { if (num==0) { printf("\t\tZero"); } num=(num*100); num2= (long)num; thousands=num2/100000; num2=num2%100000; hundreds=num2/10000; num2=num2%10000; if ((num2>=1100) || (num2<=1900)) { tens=0; ones=0; ventoteen=num2%1000; } else { tens=num2/1000; num2=num2%1000; ones=num2/100; num2=num2%100; } if((num2>=11) && (num2<=19)) { cents1=0; cents2=0; centeens=num2%10; } else { cents1=num2/10; num2=num2%10; cents2=num2/1; } if (thousands == 1) printf("One thousand "); else if (thousands == 2) printf("Two thousand "); else if (thousands == 3) printf("Three Thousand "); else if (thousands == 4) printf("Four thousand "); else if (thousands == 5) printf("Five Thousand "); else if (thousands == 6) printf("Six thousand "); else if (thousands == 7) printf("Seven Thousand "); else if (thousands == 8) printf("Eight thousand "); else if (thousands == 9) printf("Nine Thousand "); else {} if (hundreds == 1) printf("one hundred "); else if (hundreds == 2) printf("two hundred "); else if (hundreds == 3) printf("three hundred "); else if (hundreds == 4) printf("four hundred "); else if (hundreds == 5) printf("five hundred "); else if (hundreds == 6) printf("six hundred "); else if (hundreds == 7) printf("seven hundred "); else if (hundreds == 8) printf("eight hundred "); else if (hundreds == 9) printf("nine hundred "); else {} switch(ventoteen) { case 1: printf("eleven ");break; case 2: printf("twelve ");break; case 3: printf("thirteen ");break; case 4: printf("fourteen ");break; case 5: printf("fifteen ");break; case 6: printf("sixteen ");break; case 7: printf("seventeen ");break; case 8: printf("eighteen ");break; case 9: printf("nineteen ");break; } switch(tens) { case 1: printf("ten ");break; case 2: printf("twenty ");break; case 3: printf("thirty ");break; case 4: printf("forty ");break; case 5: printf("fifty ");break; case 6: printf("sixty ");break; case 7: printf("seventy ");break; case 8: printf("eighty ");break; case 9: printf("ninety ");break; } switch(ones) { case 1: printf("one ");break; case 2: printf("two ");break; case 3: printf("three ");break; case 4: printf("four ");break; case 5: printf("five ");break; case 6: printf("six ");break; case 7: printf("seven ");break; case 8: printf("eight ");break; case 9: printf("nine ");break; } switch(cents1) { case 1: printf("and ten centavos ");break; case 2: printf("and twenty centavos ");break; case 3: printf("and thirty centavos ");break; case 4: printf("and fourty centavos ");break; case 5: printf("and fifty centavos ");break; case 6: printf("and sixty centavos ");break; case 7: printf("and seventy centavos ");break; case 8: printf("and eighty centavos ");break; case 9: printf("and ninety centavos ");break; } switch(centeens) { case 1: printf("and eleven centavos ");break; case 2: printf("and twelve centavos ");break; case 3: printf("and thirteen centavos ");break; case 4: printf("and fourteen centavos ");break; case 5: printf("and fifteen centavos ");break; case 6: printf("and sixteen centavos ");break; case 7: printf("and seventeen centavos ");break; case 8: printf("and eighteen centavos ");break; case 9: printf("and nineteen centavos ");break; } switch(cents2) { case 1: printf("and one centavos ");break; case 2: printf("and two centavos ");break; case 3: printf("and three centavos ");break; case 4: printf("and four centavos ");break; case 5: printf("and five centavos ");break; case 6: printf("and six centavos ");break; case 7: printf("and seven centavos ");break; case 8: printf("and eight centavos ");break; case 9: printf("and nine centavos ");break; } } getch(); }while(myloop == 0); return 0; } my code is working fine but the problem is when i input 1 - 90 nothing appears but when i input 100 the output would be fine and that is "One Hundred" and so as 1000 the output would be "One Thousand". thanks for the help..

    Read the article

  • Saving a Join Model

    - by Thorpe Obazee
    I've been reading the cookbook for a while now and still don't get how I'm supposed to do this: My original problem was this: A related Model isn't being validated From RabidFire's commment: If you want to count the number of Category models that a new Post is associated with (on save), then you need to do this in the beforeSave function as I've mentioned. As you've currently set up your models, you don't need to use the multiple rule anywhere. If you really, really want to validate against a list of Category IDs for some reason, then create a join model, and validate category_id with the multiple rule there. Now, I have these models and are now validating. The problem now is that data isn't being saved in the Join Table: class Post extends AppModel { var $name = 'Post'; var $hasMany = array( 'CategoryPost' => array( 'className' => 'CategoryPost' ) ); var $belongsTo = array( 'Page' => array( 'className' => 'Page' ) ); class Category extends AppModel { var $name = 'Category'; var $hasMany = array( 'CategoryPost' => array( 'className' => 'CategoryPost' ) ); class CategoryPost extends AppModel { var $name = 'CategoryPost'; var $validate = array( 'category_id' => array( 'rule' => array('multiple', array('in' => array(1, 2, 3, 4))), 'required' => FALSE, 'message' => 'Please select one, two or three options' ) ); var $belongsTo = array( 'Post' => array( 'className' => 'Post' ), 'Category' => array( 'className' => 'Category' ) ); This is the new Form: <div id="content-wrap"> <div id="main"> <h2>Add Post</h2> <?php echo $this->Session->flash();?> <div> <?php echo $this->Form->create('Post'); echo $this->Form->input('Post.title'); echo $this->Form->input('CategoryPost.category_id', array('multiple' => 'checkbox')); echo $this->Form->input('Post.body', array('rows' => '3')); echo $this->Form->input('Page.meta_keywords'); echo $this->Form->input('Page.meta_description'); echo $this->Form->end('Save Post'); ?> </div> <!-- main ends --> </div> The data I am producing from the form is as follows: Array ( [Post] => Array ( [title] => 1234 [body] => 1234 ) [CategoryPost] => Array ( [category_id] => Array ( [0] => 1 [1] => 2 ) ) [Page] => Array ( [meta_keywords] => 1234 [meta_description] => 1234 [title] => 1234 [layout] => index ) ) UPDATE: controller action //Controller action function admin_add() { // pr(Debugger::trace()); $this->set('categories', $this->Post->CategoryPost->Category->find('list')); if ( ! empty($this->data)) { $this->data['Page']['title'] = $this->data['Post']['title']; $this->data['Page']['layout'] = 'index'; debug($this->data); if ($this->Post->saveAll($this->data)) { $this->Session->setFlash('Your post has been saved', 'flash_good'); $this->redirect($this->here); } } } UPDATE #2: Should I just do this manually? The problem is that the join tables doesn't have things saved in it. Is there something I'm missing? UPDATE #3 RabidFire gave me a solution. I already did this before and am quite surprised as so why it didn't work. Thus, me asking here. The reason I think there is something wrong. I don't know where: Post beforeSave: function beforeSave() { if (empty($this->id)) { $this->data[$this->name]['uri'] = $this->getUniqueUrl($this->data[$this->name]['title']); } if (isset($this->data['CategoryPost']['category_id']) && is_array($this->data['CategoryPost']['category_id'])) { echo 'test'; $categoryPosts = array(); foreach ($this->data['CategoryPost']['category_id'] as $categoryId) { $categoryPost = array( 'category_id' => $categoryId ); array_push($categoryPosts, $categoryPost); } $this->data['CategoryPost'] = $categoryPosts; } debug($this->data); // Gives RabidFire's correct array for saving. return true; } My Post action: function admin_add() { // pr(Debugger::trace()); $this->set('categories', $this->Post->CategoryPost->Category->find('list')); if ( ! empty($this->data)) { $this->data['Page']['title'] = $this->data['Post']['title']; $this->data['Page']['layout'] = 'index'; debug($this->data); // First debug is giving the correct array as above. if ($this->Post->saveAll($this->data)) { debug($this->data); // STILL gives the above array. which shouldn't be because of the beforeSave in the Post Model // $this->Session->setFlash('Your post has been saved', 'flash_good'); // $this->redirect($this->here); } } }

    Read the article

  • 256 Windows Azure Worker Roles, Windows Kinect and a 90's Text-Based Ray-Tracer

    - by Alan Smith
    For a couple of years I have been demoing a simple render farm hosted in Windows Azure using worker roles and the Azure Storage service. At the start of the presentation I deploy an Azure application that uses 16 worker roles to render a 1,500 frame 3D ray-traced animation. At the end of the presentation, when the animation was complete, I would play the animation delete the Azure deployment. The standing joke with the audience was that it was that it was a “$2 demo”, as the compute charges for running the 16 instances for an hour was $1.92, factor in the bandwidth charges and it’s a couple of dollars. The point of the demo is that it highlights one of the great benefits of cloud computing, you pay for what you use, and if you need massive compute power for a short period of time using Windows Azure can work out very cost effective. The “$2 demo” was great for presenting at user groups and conferences in that it could be deployed to Azure, used to render an animation, and then removed in a one hour session. I have always had the idea of doing something a bit more impressive with the demo, and scaling it from a “$2 demo” to a “$30 demo”. The challenge was to create a visually appealing animation in high definition format and keep the demo time down to one hour.  This article will take a run through how I achieved this. Ray Tracing Ray tracing, a technique for generating high quality photorealistic images, gained popularity in the 90’s with companies like Pixar creating feature length computer animations, and also the emergence of shareware text-based ray tracers that could run on a home PC. In order to render a ray traced image, the ray of light that would pass from the view point must be tracked until it intersects with an object. At the intersection, the color, reflectiveness, transparency, and refractive index of the object are used to calculate if the ray will be reflected or refracted. Each pixel may require thousands of calculations to determine what color it will be in the rendered image. Pin-Board Toys Having very little artistic talent and a basic understanding of maths I decided to focus on an animation that could be modeled fairly easily and would look visually impressive. I’ve always liked the pin-board desktop toys that become popular in the 80’s and when I was working as a 3D animator back in the 90’s I always had the idea of creating a 3D ray-traced animation of a pin-board, but never found the energy to do it. Even if I had a go at it, the render time to produce an animation that would look respectable on a 486 would have been measured in months. PolyRay Back in 1995 I landed my first real job, after spending three years being a beach-ski-climbing-paragliding-bum, and was employed to create 3D ray-traced animations for a CD-ROM that school kids would use to learn physics. I had got into the strange and wonderful world of text-based ray tracing, and was using a shareware ray-tracer called PolyRay. PolyRay takes a text file describing a scene as input and, after a few hours processing on a 486, produced a high quality ray-traced image. The following is an example of a basic PolyRay scene file. background Midnight_Blue   static define matte surface { ambient 0.1 diffuse 0.7 } define matte_white texture { matte { color white } } define matte_black texture { matte { color dark_slate_gray } } define position_cylindrical 3 define lookup_sawtooth 1 define light_wood <0.6, 0.24, 0.1> define median_wood <0.3, 0.12, 0.03> define dark_wood <0.05, 0.01, 0.005>     define wooden texture { noise surface { ambient 0.2  diffuse 0.7  specular white, 0.5 microfacet Reitz 10 position_fn position_cylindrical position_scale 1  lookup_fn lookup_sawtooth octaves 1 turbulence 1 color_map( [0.0, 0.2, light_wood, light_wood] [0.2, 0.3, light_wood, median_wood] [0.3, 0.4, median_wood, light_wood] [0.4, 0.7, light_wood, light_wood] [0.7, 0.8, light_wood, median_wood] [0.8, 0.9, median_wood, light_wood] [0.9, 1.0, light_wood, dark_wood]) } } define glass texture { surface { ambient 0 diffuse 0 specular 0.2 reflection white, 0.1 transmission white, 1, 1.5 }} define shiny surface { ambient 0.1 diffuse 0.6 specular white, 0.6 microfacet Phong 7  } define steely_blue texture { shiny { color black } } define chrome texture { surface { color white ambient 0.0 diffuse 0.2 specular 0.4 microfacet Phong 10 reflection 0.8 } }   viewpoint {     from <4.000, -1.000, 1.000> at <0.000, 0.000, 0.000> up <0, 1, 0> angle 60     resolution 640, 480 aspect 1.6 image_format 0 }       light <-10, 30, 20> light <-10, 30, -20>   object { disc <0, -2, 0>, <0, 1, 0>, 30 wooden }   object { sphere <0.000, 0.000, 0.000>, 1.00 chrome } object { cylinder <0.000, 0.000, 0.000>, <0.000, 0.000, -4.000>, 0.50 chrome }   After setting up the background and defining colors and textures, the viewpoint is specified. The “camera” is located at a point in 3D space, and it looks towards another point. The angle, image resolution, and aspect ratio are specified. Two lights are present in the image at defined coordinates. The three objects in the image are a wooden disc to represent a table top, and a sphere and cylinder that intersect to form a pin that will be used for the pin board toy in the final animation. When the image is rendered, the following image is produced. The pins are modeled with a chrome surface, so they reflect the environment around them. Note that the scale of the pin shaft is not correct, this will be fixed later. Modeling the Pin Board The frame of the pin-board is made up of three boxes, and six cylinders, the front box is modeled using a clear, slightly reflective solid, with the same refractive index of glass. The other shapes are modeled as metal. object { box <-5.5, -1.5, 1>, <5.5, 5.5, 1.2> glass } object { box <-5.5, -1.5, -0.04>, <5.5, 5.5, -0.09> steely_blue } object { box <-5.5, -1.5, -0.52>, <5.5, 5.5, -0.59> steely_blue } object { cylinder <-5.2, -1.2, 1.4>, <-5.2, -1.2, -0.74>, 0.2 steely_blue } object { cylinder <5.2, -1.2, 1.4>, <5.2, -1.2, -0.74>, 0.2 steely_blue } object { cylinder <-5.2, 5.2, 1.4>, <-5.2, 5.2, -0.74>, 0.2 steely_blue } object { cylinder <5.2, 5.2, 1.4>, <5.2, 5.2, -0.74>, 0.2 steely_blue } object { cylinder <0, -1.2, 1.4>, <0, -1.2, -0.74>, 0.2 steely_blue } object { cylinder <0, 5.2, 1.4>, <0, 5.2, -0.74>, 0.2 steely_blue }   In order to create the matrix of pins that make up the pin board I used a basic console application with a few nested loops to create two intersecting matrixes of pins, which models the layout used in the pin boards. The resulting image is shown below. The pin board contains 11,481 pins, with the scene file containing 23,709 lines of code. For the complete animation 2,000 scene files will be created, which is over 47 million lines of code. Each pin in the pin-board will slide out a specific distance when an object is pressed into the back of the board. This is easily modeled by setting the Z coordinate of the pin to a specific value. In order to set all of the pins in the pin-board to the correct position, a bitmap image can be used. The position of the pin can be set based on the color of the pixel at the appropriate position in the image. When the Windows Azure logo is used to set the Z coordinate of the pins, the following image is generated. The challenge now was to make a cool animation. The Azure Logo is fine, but it is static. Using a normal video to animate the pins would not work; the colors in the video would not be the same as the depth of the objects from the camera. In order to simulate the pin board accurately a series of frames from a depth camera could be used. Windows Kinect The Kenect controllers for the X-Box 360 and Windows feature a depth camera. The Kinect SDK for Windows provides a programming interface for Kenect, providing easy access for .NET developers to the Kinect sensors. The Kinect Explorer provided with the Kinect SDK is a great starting point for exploring Kinect from a developers perspective. Both the X-Box 360 Kinect and the Windows Kinect will work with the Kinect SDK, the Windows Kinect is required for commercial applications, but the X-Box Kinect can be used for hobby projects. The Windows Kinect has the advantage of providing a mode to allow depth capture with objects closer to the camera, which makes for a more accurate depth image for setting the pin positions. Creating a Depth Field Animation The depth field animation used to set the positions of the pin in the pin board was created using a modified version of the Kinect Explorer sample application. In order to simulate the pin board accurately, a small section of the depth range from the depth sensor will be used. Any part of the object in front of the depth range will result in a white pixel; anything behind the depth range will be black. Within the depth range the pixels in the image will be set to RGB values from 0,0,0 to 255,255,255. A screen shot of the modified Kinect Explorer application is shown below. The Kinect Explorer sample application was modified to include slider controls that are used to set the depth range that forms the image from the depth stream. This allows the fine tuning of the depth image that is required for simulating the position of the pins in the pin board. The Kinect Explorer was also modified to record a series of images from the depth camera and save them as a sequence JPEG files that will be used to animate the pins in the animation the Start and Stop buttons are used to start and stop the image recording. En example of one of the depth images is shown below. Once a series of 2,000 depth images has been captured, the task of creating the animation can begin. Rendering a Test Frame In order to test the creation of frames and get an approximation of the time required to render each frame a test frame was rendered on-premise using PolyRay. The output of the rendering process is shown below. The test frame contained 23,629 primitive shapes, most of which are the spheres and cylinders that are used for the 11,800 or so pins in the pin board. The 1280x720 image contains 921,600 pixels, but as anti-aliasing was used the number of rays that were calculated was 4,235,777, with 3,478,754,073 object boundaries checked. The test frame of the pin board with the depth field image applied is shown below. The tracing time for the test frame was 4 minutes 27 seconds, which means rendering the2,000 frames in the animation would take over 148 hours, or a little over 6 days. Although this is much faster that an old 486, waiting almost a week to see the results of an animation would make it challenging for animators to create, view, and refine their animations. It would be much better if the animation could be rendered in less than one hour. Windows Azure Worker Roles The cost of creating an on-premise render farm to render animations increases in proportion to the number of servers. The table below shows the cost of servers for creating a render farm, assuming a cost of $500 per server. Number of Servers Cost 1 $500 16 $8,000 256 $128,000   As well as the cost of the servers, there would be additional costs for networking, racks etc. Hosting an environment of 256 servers on-premise would require a server room with cooling, and some pretty hefty power cabling. The Windows Azure compute services provide worker roles, which are ideal for performing processor intensive compute tasks. With the scalability available in Windows Azure a job that takes 256 hours to complete could be perfumed using different numbers of worker roles. The time and cost of using 1, 16 or 256 worker roles is shown below. Number of Worker Roles Render Time Cost 1 256 hours $30.72 16 16 hours $30.72 256 1 hour $30.72   Using worker roles in Windows Azure provides the same cost for the 256 hour job, irrespective of the number of worker roles used. Provided the compute task can be broken down into many small units, and the worker role compute power can be used effectively, it makes sense to scale the application so that the task is completed quickly, making the results available in a timely fashion. The task of rendering 2,000 frames in an animation is one that can easily be broken down into 2,000 individual pieces, which can be performed by a number of worker roles. Creating a Render Farm in Windows Azure The architecture of the render farm is shown in the following diagram. The render farm is a hybrid application with the following components: ·         On-Premise o   Windows Kinect – Used combined with the Kinect Explorer to create a stream of depth images. o   Animation Creator – This application uses the depth images from the Kinect sensor to create scene description files for PolyRay. These files are then uploaded to the jobs blob container, and job messages added to the jobs queue. o   Process Monitor – This application queries the role instance lifecycle table and displays statistics about the render farm environment and render process. o   Image Downloader – This application polls the image queue and downloads the rendered animation files once they are complete. ·         Windows Azure o   Azure Storage – Queues and blobs are used for the scene description files and completed frames. A table is used to store the statistics about the rendering environment.   The architecture of each worker role is shown below.   The worker role is configured to use local storage, which provides file storage on the worker role instance that can be use by the applications to render the image and transform the format of the image. The service definition for the worker role with the local storage configuration highlighted is shown below. <?xml version="1.0" encoding="utf-8"?> <ServiceDefinition name="CloudRay" >   <WorkerRole name="CloudRayWorkerRole" vmsize="Small">     <Imports>     </Imports>     <ConfigurationSettings>       <Setting name="DataConnectionString" />     </ConfigurationSettings>     <LocalResources>       <LocalStorage name="RayFolder" cleanOnRoleRecycle="true" />     </LocalResources>   </WorkerRole> </ServiceDefinition>     The two executable programs, PolyRay.exe and DTA.exe are included in the Azure project, with Copy Always set as the property. PolyRay will take the scene description file and render it to a Truevision TGA file. As the TGA format has not seen much use since the mid 90’s it is converted to a JPG image using Dave's Targa Animator, another shareware application from the 90’s. Each worker roll will use the following process to render the animation frames. 1.       The worker process polls the job queue, if a job is available the scene description file is downloaded from blob storage to local storage. 2.       PolyRay.exe is started in a process with the appropriate command line arguments to render the image as a TGA file. 3.       DTA.exe is started in a process with the appropriate command line arguments convert the TGA file to a JPG file. 4.       The JPG file is uploaded from local storage to the images blob container. 5.       A message is placed on the images queue to indicate a new image is available for download. 6.       The job message is deleted from the job queue. 7.       The role instance lifecycle table is updated with statistics on the number of frames rendered by the worker role instance, and the CPU time used. The code for this is shown below. public override void Run() {     // Set environment variables     string polyRayPath = Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), PolyRayLocation);     string dtaPath = Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), DTALocation);       LocalResource rayStorage = RoleEnvironment.GetLocalResource("RayFolder");     string localStorageRootPath = rayStorage.RootPath;       JobQueue jobQueue = new JobQueue("renderjobs");     JobQueue downloadQueue = new JobQueue("renderimagedownloadjobs");     CloudRayBlob sceneBlob = new CloudRayBlob("scenes");     CloudRayBlob imageBlob = new CloudRayBlob("images");     RoleLifecycleDataSource roleLifecycleDataSource = new RoleLifecycleDataSource();       Frames = 0;       while (true)     {         // Get the render job from the queue         CloudQueueMessage jobMsg = jobQueue.Get();           if (jobMsg != null)         {             // Get the file details             string sceneFile = jobMsg.AsString;             string tgaFile = sceneFile.Replace(".pi", ".tga");             string jpgFile = sceneFile.Replace(".pi", ".jpg");               string sceneFilePath = Path.Combine(localStorageRootPath, sceneFile);             string tgaFilePath = Path.Combine(localStorageRootPath, tgaFile);             string jpgFilePath = Path.Combine(localStorageRootPath, jpgFile);               // Copy the scene file to local storage             sceneBlob.DownloadFile(sceneFilePath);               // Run the ray tracer.             string polyrayArguments =                 string.Format("\"{0}\" -o \"{1}\" -a 2", sceneFilePath, tgaFilePath);             Process polyRayProcess = new Process();             polyRayProcess.StartInfo.FileName =                 Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), polyRayPath);             polyRayProcess.StartInfo.Arguments = polyrayArguments;             polyRayProcess.Start();             polyRayProcess.WaitForExit();               // Convert the image             string dtaArguments =                 string.Format(" {0} /FJ /P{1}", tgaFilePath, Path.GetDirectoryName (jpgFilePath));             Process dtaProcess = new Process();             dtaProcess.StartInfo.FileName =                 Path.Combine(Environment.GetEnvironmentVariable("RoleRoot"), dtaPath);             dtaProcess.StartInfo.Arguments = dtaArguments;             dtaProcess.Start();             dtaProcess.WaitForExit();               // Upload the image to blob storage             imageBlob.UploadFile(jpgFilePath);               // Add a download job.             downloadQueue.Add(jpgFile);               // Delete the render job message             jobQueue.Delete(jobMsg);               Frames++;         }         else         {             Thread.Sleep(1000);         }           // Log the worker role activity.         roleLifecycleDataSource.Alive             ("CloudRayWorker", RoleLifecycleDataSource.RoleLifecycleId, Frames);     } }     Monitoring Worker Role Instance Lifecycle In order to get more accurate statistics about the lifecycle of the worker role instances used to render the animation data was tracked in an Azure storage table. The following class was used to track the worker role lifecycles in Azure storage.   public class RoleLifecycle : TableServiceEntity {     public string ServerName { get; set; }     public string Status { get; set; }     public DateTime StartTime { get; set; }     public DateTime EndTime { get; set; }     public long SecondsRunning { get; set; }     public DateTime LastActiveTime { get; set; }     public int Frames { get; set; }     public string Comment { get; set; }       public RoleLifecycle()     {     }       public RoleLifecycle(string roleName)     {         PartitionKey = roleName;         RowKey = Utils.GetAscendingRowKey();         Status = "Started";         StartTime = DateTime.UtcNow;         LastActiveTime = StartTime;         EndTime = StartTime;         SecondsRunning = 0;         Frames = 0;     } }     A new instance of this class is created and added to the storage table when the role starts. It is then updated each time the worker renders a frame to record the total number of frames rendered and the total processing time. These statistics are used be the monitoring application to determine the effectiveness of use of resources in the render farm. Rendering the Animation The Azure solution was deployed to Windows Azure with the service configuration set to 16 worker role instances. This allows for the application to be tested in the cloud environment, and the performance of the application determined. When I demo the application at conferences and user groups I often start with 16 instances, and then scale up the application to the full 256 instances. The configuration to run 16 instances is shown below. <?xml version="1.0" encoding="utf-8"?> <ServiceConfiguration serviceName="CloudRay" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration" osFamily="1" osVersion="*">   <Role name="CloudRayWorkerRole">     <Instances count="16" />     <ConfigurationSettings>       <Setting name="DataConnectionString"         value="DefaultEndpointsProtocol=https;AccountName=cloudraydata;AccountKey=..." />     </ConfigurationSettings>   </Role> </ServiceConfiguration>     About six minutes after deploying the application the first worker roles become active and start to render the first frames of the animation. The CloudRay Monitor application displays an icon for each worker role instance, with a number indicating the number of frames that the worker role has rendered. The statistics on the left show the number of active worker roles and statistics about the render process. The render time is the time since the first worker role became active; the CPU time is the total amount of processing time used by all worker role instances to render the frames.   Five minutes after the first worker role became active the last of the 16 worker roles activated. By this time the first seven worker roles had each rendered one frame of the animation.   With 16 worker roles u and running it can be seen that one hour and 45 minutes CPU time has been used to render 32 frames with a render time of just under 10 minutes.     At this rate it would take over 10 hours to render the 2,000 frames of the full animation. In order to complete the animation in under an hour more processing power will be required. Scaling the render farm from 16 instances to 256 instances is easy using the new management portal. The slider is set to 256 instances, and the configuration saved. We do not need to re-deploy the application, and the 16 instances that are up and running will not be affected. Alternatively, the configuration file for the Azure service could be modified to specify 256 instances.   <?xml version="1.0" encoding="utf-8"?> <ServiceConfiguration serviceName="CloudRay" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration" osFamily="1" osVersion="*">   <Role name="CloudRayWorkerRole">     <Instances count="256" />     <ConfigurationSettings>       <Setting name="DataConnectionString"         value="DefaultEndpointsProtocol=https;AccountName=cloudraydata;AccountKey=..." />     </ConfigurationSettings>   </Role> </ServiceConfiguration>     Six minutes after the new configuration has been applied 75 new worker roles have activated and are processing their first frames.   Five minutes later the full configuration of 256 worker roles is up and running. We can see that the average rate of frame rendering has increased from 3 to 12 frames per minute, and that over 17 hours of CPU time has been utilized in 23 minutes. In this test the time to provision 140 worker roles was about 11 minutes, which works out at about one every five seconds.   We are now half way through the rendering, with 1,000 frames complete. This has utilized just under three days of CPU time in a little over 35 minutes.   The animation is now complete, with 2,000 frames rendered in a little over 52 minutes. The CPU time used by the 256 worker roles is 6 days, 7 hours and 22 minutes with an average frame rate of 38 frames per minute. The rendering of the last 1,000 frames took 16 minutes 27 seconds, which works out at a rendering rate of 60 frames per minute. The frame counts in the server instances indicate that the use of a queue to distribute the workload has been very effective in distributing the load across the 256 worker role instances. The first 16 instances that were deployed first have rendered between 11 and 13 frames each, whilst the 240 instances that were added when the application was scaled have rendered between 6 and 9 frames each.   Completed Animation I’ve uploaded the completed animation to YouTube, a low resolution preview is shown below. Pin Board Animation Created using Windows Kinect and 256 Windows Azure Worker Roles   The animation can be viewed in 1280x720 resolution at the following link: http://www.youtube.com/watch?v=n5jy6bvSxWc Effective Use of Resources According to the CloudRay monitor statistics the animation took 6 days, 7 hours and 22 minutes CPU to render, this works out at 152 hours of compute time, rounded up to the nearest hour. As the usage for the worker role instances are billed for the full hour, it may have been possible to render the animation using fewer than 256 worker roles. When deciding the optimal usage of resources, the time required to provision and start the worker roles must also be considered. In the demo I started with 16 worker roles, and then scaled the application to 256 worker roles. It would have been more optimal to start the application with maybe 200 worker roles, and utilized the full hour that I was being billed for. This would, however, have prevented showing the ease of scalability of the application. The new management portal displays the CPU usage across the worker roles in the deployment. The average CPU usage across all instances is 93.27%, with over 99% used when all the instances are up and running. This shows that the worker role resources are being used very effectively. Grid Computing Scenarios Although I am using this scenario for a hobby project, there are many scenarios where a large amount of compute power is required for a short period of time. Windows Azure provides a great platform for developing these types of grid computing applications, and can work out very cost effective. ·         Windows Azure can provide massive compute power, on demand, in a matter of minutes. ·         The use of queues to manage the load balancing of jobs between role instances is a simple and effective solution. ·         Using a cloud-computing platform like Windows Azure allows proof-of-concept scenarios to be tested and evaluated on a very low budget. ·         No charges for inbound data transfer makes the uploading of large data sets to Windows Azure Storage services cost effective. (Transaction charges still apply.) Tips for using Windows Azure for Grid Computing Scenarios I found the implementation of a render farm using Windows Azure a fairly simple scenario to implement. I was impressed by ease of scalability that Azure provides, and by the short time that the application took to scale from 16 to 256 worker role instances. In this case it was around 13 minutes, in other tests it took between 10 and 20 minutes. The following tips may be useful when implementing a grid computing project in Windows Azure. ·         Using an Azure Storage queue to load-balance the units of work across multiple worker roles is simple and very effective. The design I have used in this scenario could easily scale to many thousands of worker role instances. ·         Windows Azure accounts are typically limited to 20 cores. If you need to use more than this, a call to support and a credit card check will be required. ·         Be aware of how the billing model works. You will be charged for worker role instances for the full clock our in which the instance is deployed. Schedule the workload to start just after the clock hour has started. ·         Monitor the utilization of the resources you are provisioning, ensure that you are not paying for worker roles that are idle. ·         If you are deploying third party applications to worker roles, you may well run into licensing issues. Purchasing software licenses on a per-processor basis when using hundreds of processors for a short time period would not be cost effective. ·         Third party software may also require installation onto the worker roles, which can be accomplished using start-up tasks. Bear in mind that adding a startup task and possible re-boot will add to the time required for the worker role instance to start and activate. An alternative may be to use a prepared VM and use VM roles. ·         Consider using the Windows Azure Autoscaling Application Block (WASABi) to autoscale the worker roles in your application. When using a large number of worker roles, the utilization must be carefully monitored, if the scaling algorithms are not optimal it could get very expensive!

    Read the article

  • Diving into OpenStack Network Architecture - Part 2 - Basic Use Cases

    - by Ronen Kofman
      rkofman Normal rkofman 4 138 2014-06-05T03:38:00Z 2014-06-05T05:04:00Z 3 2735 15596 Oracle Corporation 129 36 18295 12.00 Clean Clean false false false false EN-US X-NONE HE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi; mso-bidi-language:AR-SA;} In the previous post we reviewed several network components including Open vSwitch, Network Namespaces, Linux Bridges and veth pairs. In this post we will take three simple use cases and see how those basic components come together to create a complete SDN solution in OpenStack. With those three use cases we will review almost the entire network setup and see how all the pieces work together. The use cases we will use are: 1.       Create network – what happens when we create network and how can we create multiple isolated networks 2.       Launch a VM – once we have networks we can launch VMs and connect them to networks. 3.       DHCP request from a VM – OpenStack can automatically assign IP addresses to VMs. This is done through local DHCP service controlled by OpenStack Neutron. We will see how this service runs and how does a DHCP request and response look like. In this post we will show connectivity, we will see how packets get from point A to point B. We first focus on how a configured deployment looks like and only later we will discuss how and when the configuration is created. Personally I found it very valuable to see the actual interfaces and how they connect to each other through examples and hands on experiments. After the end game is clear and we know how the connectivity works, in a later post, we will take a step back and explain how Neutron configures the components to be able to provide such connectivity.  We are going to get pretty technical shortly and I recommend trying these examples on your own deployment or using the Oracle OpenStack Tech Preview. Understanding these three use cases thoroughly and how to look at them will be very helpful when trying to debug a deployment in case something does not work. Use case #1: Create Network Create network is a simple operation it can be performed from the GUI or command line. When we create a network in OpenStack the network is only available to the tenant who created it or it could be defined as “shared” and then it can be used by all tenants. A network can have multiple subnets but for this demonstration purpose and for simplicity we will assume that each network has exactly one subnet. Creating a network from the command line will look like this: # neutron net-create net1 Created a new network: +---------------------------+--------------------------------------+ | Field                     | Value                                | +---------------------------+--------------------------------------+ | admin_state_up            | True                                 | | id                        | 5f833617-6179-4797-b7c0-7d420d84040c | | name                      | net1                                 | | provider:network_type     | vlan                                 | | provider:physical_network | default                              | | provider:segmentation_id  | 1000                                 | | shared                    | False                                | | status                    | ACTIVE                               | | subnets                   |                                      | | tenant_id                 | 9796e5145ee546508939cd49ad59d51f     | +---------------------------+--------------------------------------+ Creating a subnet for this network will look like this: # neutron subnet-create net1 10.10.10.0/24 Created a new subnet: +------------------+------------------------------------------------+ | Field            | Value                                          | +------------------+------------------------------------------------+ | allocation_pools | {"start": "10.10.10.2", "end": "10.10.10.254"} | | cidr             | 10.10.10.0/24                                  | | dns_nameservers  |                                                | | enable_dhcp      | True                                           | | gateway_ip       | 10.10.10.1                                     | | host_routes      |                                                | | id               | 2d7a0a58-0674-439a-ad23-d6471aaae9bc           | | ip_version       | 4                                              | | name             |                                                | | network_id       | 5f833617-6179-4797-b7c0-7d420d84040c           | | tenant_id        | 9796e5145ee546508939cd49ad59d51f               | +------------------+------------------------------------------------+ We now have a network and a subnet, on the network topology view this looks like this: Now let’s dive in and see what happened under the hood. Looking at the control node we will discover that a new namespace was created: # ip netns list qdhcp-5f833617-6179-4797-b7c0-7d420d84040c   The name of the namespace is qdhcp-<network id> (see above), let’s look into the namespace and see what’s in it: # ip netns exec qdhcp-5f833617-6179-4797-b7c0-7d420d84040c ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00     inet 127.0.0.1/8 scope host lo     inet6 ::1/128 scope host        valid_lft forever preferred_lft forever 12: tap26c9b807-7c: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN     link/ether fa:16:3e:1d:5c:81 brd ff:ff:ff:ff:ff:ff     inet 10.10.10.3/24 brd 10.10.10.255 scope global tap26c9b807-7c     inet6 fe80::f816:3eff:fe1d:5c81/64 scope link        valid_lft forever preferred_lft forever   We see two interfaces in the namespace, one is the loopback and the other one is an interface called “tap26c9b807-7c”. This interface has the IP address of 10.10.10.3 and it will also serve dhcp requests in a way we will see later. Let’s trace the connectivity of the “tap26c9b807-7c” interface from the namespace.  First stop is OVS, we see that the interface connects to bridge  “br-int” on OVS: # ovs-vsctl show 8a069c7c-ea05-4375-93e2-b9fc9e4b3ca1     Bridge "br-eth2"         Port "br-eth2"             Interface "br-eth2"                 type: internal         Port "eth2"             Interface "eth2"         Port "phy-br-eth2"             Interface "phy-br-eth2"     Bridge br-ex         Port br-ex             Interface br-ex                 type: internal     Bridge br-int         Port "int-br-eth2"             Interface "int-br-eth2"         Port "tap26c9b807-7c"             tag: 1             Interface "tap26c9b807-7c"                 type: internal         Port br-int             Interface br-int                 type: internal     ovs_version: "1.11.0"   In the picture above we have a veth pair which has two ends called “int-br-eth2” and "phy-br-eth2", this veth pair is used to connect two bridge in OVS "br-eth2" and "br-int". In the previous post we explained how to check the veth connectivity using the ethtool command. It shows that the two are indeed a pair: # ethtool -S int-br-eth2 NIC statistics:      peer_ifindex: 10 . .   #ip link . . 10: phy-br-eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 . . Note that “phy-br-eth2” is connected to a bridge called "br-eth2" and one of this bridge's interfaces is the physical link eth2. This means that the network which we have just created has created a namespace which is connected to the physical interface eth2. eth2 is the “VM network” the physical interface where all the virtual machines connect to where all the VMs are connected. About network isolation: OpenStack supports creation of multiple isolated networks and can use several mechanisms to isolate the networks from one another. The isolation mechanism can be VLANs, VxLANs or GRE tunnels, this is configured as part of the initial setup in our deployment we use VLANs. When using VLAN tagging as an isolation mechanism a VLAN tag is allocated by Neutron from a pre-defined VLAN tags pool and assigned to the newly created network. By provisioning VLAN tags to the networks Neutron allows creation of multiple isolated networks on the same physical link.  The big difference between this and other platforms is that the user does not have to deal with allocating and managing VLANs to networks. The VLAN allocation and provisioning is handled by Neutron which keeps track of the VLAN tags, and responsible for allocating and reclaiming VLAN tags. In the example above net1 has the VLAN tag 1000, this means that whenever a VM is created and connected to this network the packets from that VM will have to be tagged with VLAN tag 1000 to go on this particular network. This is true for namespace as well, if we would like to connect a namespace to a particular network we have to make sure that the packets to and from the namespace are correctly tagged when they reach the VM network. In the example above we see that the namespace interface “tap26c9b807-7c” has vlan tag 1 assigned to it, if we examine OVS we see that it has flows which modify VLAN tag 1 to VLAN tag 1000 when a packet goes to the VM network on eth2 and vice versa. We can see this using the dump-flows command on OVS for packets going to the VM network we see the modification done on br-eth2: #  ovs-ofctl dump-flows br-eth2 NXST_FLOW reply (xid=0x4):  cookie=0x0, duration=18669.401s, table=0, n_packets=857, n_bytes=163350, idle_age=25, priority=4,in_port=2,dl_vlan=1 actions=mod_vlan_vid:1000,NORMAL  cookie=0x0, duration=165108.226s, table=0, n_packets=14, n_bytes=1000, idle_age=5343, hard_age=65534, priority=2,in_port=2 actions=drop  cookie=0x0, duration=165109.813s, table=0, n_packets=1671, n_bytes=213304, idle_age=25, hard_age=65534, priority=1 actions=NORMAL   For packets coming from the interface to the namespace we see the following modification: #  ovs-ofctl dump-flows br-int NXST_FLOW reply (xid=0x4):  cookie=0x0, duration=18690.876s, table=0, n_packets=1610, n_bytes=210752, idle_age=1, priority=3,in_port=1,dl_vlan=1000 actions=mod_vlan_vid:1,NORMAL  cookie=0x0, duration=165130.01s, table=0, n_packets=75, n_bytes=3686, idle_age=4212, hard_age=65534, priority=2,in_port=1 actions=drop  cookie=0x0, duration=165131.96s, table=0, n_packets=863, n_bytes=160727, idle_age=1, hard_age=65534, priority=1 actions=NORMAL   To summarize we can see that when a user creates a network Neutron creates a namespace and this namespace is connected through OVS to the “VM network”. OVS also takes care of tagging the packets from the namespace to the VM network with the correct VLAN tag and knows to modify the VLAN for packets coming from VM network to the namespace. Now let’s see what happens when a VM is launched and how it is connected to the “VM network”. Use case #2: Launch a VM Launching a VM can be done from Horizon or from the command line this is how we do it from Horizon: Attach the network: And Launch Once the virtual machine is up and running we can see the associated IP using the nova list command : # nova list +--------------------------------------+--------------+--------+------------+-------------+-----------------+ | ID                                   | Name         | Status | Task State | Power State | Networks        | +--------------------------------------+--------------+--------+------------+-------------+-----------------+ | 3707ac87-4f5d-4349-b7ed-3a673f55e5e1 | Oracle Linux | ACTIVE | None       | Running     | net1=10.10.10.2 | +--------------------------------------+--------------+--------+------------+-------------+-----------------+ The nova list command shows us that the VM is running and that the IP 10.10.10.2 is assigned to this VM. Let’s trace the connectivity from the VM to VM network on eth2 starting with the VM definition file. The configuration files of the VM including the virtual disk(s), in case of ephemeral storage, are stored on the compute node at/var/lib/nova/instances/<instance-id>/. Looking into the VM definition file ,libvirt.xml,  we see that the VM is connected to an interface called “tap53903a95-82” which is connected to a Linux bridge called “qbr53903a95-82”: <interface type="bridge">       <mac address="fa:16:3e:fe:c7:87"/>       <source bridge="qbr53903a95-82"/>       <target dev="tap53903a95-82"/>     </interface>   Looking at the bridge using the brctl show command we see this: # brctl show bridge name     bridge id               STP enabled     interfaces qbr53903a95-82          8000.7e7f3282b836       no              qvb53903a95-82                                                         tap53903a95-82    The bridge has two interfaces, one connected to the VM (“tap53903a95-82 “) and another one ( “qvb53903a95-82”) connected to “br-int” bridge on OVS: # ovs-vsctl show 83c42f80-77e9-46c8-8560-7697d76de51c     Bridge "br-eth2"         Port "br-eth2"             Interface "br-eth2"                 type: internal         Port "eth2"             Interface "eth2"         Port "phy-br-eth2"             Interface "phy-br-eth2"     Bridge br-int         Port br-int             Interface br-int                 type: internal         Port "int-br-eth2"             Interface "int-br-eth2"         Port "qvo53903a95-82"             tag: 3             Interface "qvo53903a95-82"     ovs_version: "1.11.0"   As we showed earlier “br-int” is connected to “br-eth2” on OVS using the veth pair int-br-eth2,phy-br-eth2 and br-eth2 is connected to the physical interface eth2. The whole flow end to end looks like this: VM è tap53903a95-82 (virtual interface)è qbr53903a95-82 (Linux bridge) è qvb53903a95-82 (interface connected from Linux bridge to OVS bridge br-int) è int-br-eth2 (veth one end) è phy-br-eth2 (veth the other end) è eth2 physical interface. The purpose of the Linux Bridge connecting to the VM is to allow security group enforcement with iptables. Security groups are enforced at the edge point which are the interface of the VM, since iptables nnot be applied to OVS bridges we use Linux bridge to apply them. In the future we hope to see this Linux Bridge going away rules.  VLAN tags: As we discussed in the first use case net1 is using VLAN tag 1000, looking at OVS above we see that qvo41f1ebcf-7c is tagged with VLAN tag 3. The modification from VLAN tag 3 to 1000 as we go to the physical network is done by OVS  as part of the packet flow of br-eth2 in the same way we showed before. To summarize, when a VM is launched it is connected to the VM network through a chain of elements as described here. During the packet from VM to the network and back the VLAN tag is modified. Use case #3: Serving a DHCP request coming from the virtual machine In the previous use cases we have shown that both the namespace called dhcp-<some id> and the VM end up connecting to the physical interface eth2  on their respective nodes, both will tag their packets with VLAN tag 1000.We saw that the namespace has an interface with IP of 10.10.10.3. Since the VM and the namespace are connected to each other and have interfaces on the same subnet they can ping each other, in this picture we see a ping from the VM which was assigned 10.10.10.2 to the namespace: The fact that they are connected and can ping each other can become very handy when something doesn’t work right and we need to isolate the problem. In such case knowing that we should be able to ping from the VM to the namespace and back can be used to trace the disconnect using tcpdump or other monitoring tools. To serve DHCP requests coming from VMs on the network Neutron uses a Linux tool called “dnsmasq”,this is a lightweight DNS and DHCP service you can read more about it here. If we look at the dnsmasq on the control node with the ps command we see this: dnsmasq --no-hosts --no-resolv --strict-order --bind-interfaces --interface=tap26c9b807-7c --except-interface=lo --pid-file=/var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/pid --dhcp-hostsfile=/var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/host --dhcp-optsfile=/var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/opts --leasefile-ro --dhcp-range=tag0,10.10.10.0,static,120s --dhcp-lease-max=256 --conf-file= --domain=openstacklocal The service connects to the tap interface in the namespace (“--interface=tap26c9b807-7c”), If we look at the hosts file we see this: # cat  /var/lib/neutron/dhcp/5f833617-6179-4797-b7c0-7d420d84040c/host fa:16:3e:fe:c7:87,host-10-10-10-2.openstacklocal,10.10.10.2   If you look at the console output above you can see the MAC address fa:16:3e:fe:c7:87 which is the VM MAC. This MAC address is mapped to IP 10.10.10.2 and so when a DHCP request comes with this MAC dnsmasq will return the 10.10.10.2.If we look into the namespace at the time we initiate a DHCP request from the VM (this can be done by simply restarting the network service in the VM) we see the following: # ip netns exec qdhcp-5f833617-6179-4797-b7c0-7d420d84040c tcpdump -n 19:27:12.191280 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:fe:c7:87, length 310 19:27:12.191666 IP 10.10.10.3.bootps > 10.10.10.2.bootpc: BOOTP/DHCP, Reply, length 325   To summarize, the DHCP service is handled by dnsmasq which is configured by Neutron to listen to the interface in the DHCP namespace. Neutron also configures dnsmasq with the combination of MAC and IP so when a DHCP request comes along it will receive the assigned IP. Summary In this post we relied on the components described in the previous post and saw how network connectivity is achieved using three simple use cases. These use cases gave a good view of the entire network stack and helped understand how an end to end connection is being made between a VM on a compute node and the DHCP namespace on the control node. One conclusion we can draw from what we saw here is that if we launch a VM and it is able to perform a DHCP request and receive a correct IP then there is reason to believe that the network is working as expected. We saw that a packet has to travel through a long list of components before reaching its destination and if it has done so successfully this means that many components are functioning properly. In the next post we will look at some more sophisticated services Neutron supports and see how they work. We will see that while there are some more components involved for the most part the concepts are the same. @RonenKofman

    Read the article

  • Nginx HTTPS redirects causing loop

    - by Ben Chiappetta
    I've been banging my head against the wall trying to figure this out, so if anyone can help I'd appreciate it. My Nginx conf has three different redirect loops, haven't been able to get any of the three to work right. The three problem areas are: Redirecting memcache directory to SSL Redirecting accounts directory to SSL Redirecting SSL to www if non-www nginx.conf: user nginx; worker_processes 1; error_log /var/log/nginx/error.log warn; pid /var/run/nginx.pid; events { worker_connections 1024; } http { include /etc/nginx/mime.types; default_type application/octet-stream; log_format main '$remote_addr - $remote_user [$time_local] "$request" ' '$status $body_bytes_sent "$http_referer" ' '"$http_user_agent" "$http_x_forwarded_for"'; access_log /var/log/nginx/access.log main; error_log /var/log/nginx/error.log notice; sendfile on; #tcp_nopush on; keepalive_timeout 65; proxy_set_header X-Url-Scheme $scheme; #gzip on; rewrite_log on; include /etc/nginx/conf.d/*.conf; } conf.d/default.conf: server { listen 80; server_name <redacted>.net; rewrite ^(.*) http://www.<redacted>.net$1; } server { listen 80; server_name www.<redacted>.net; set_real_ip_from 192.168.30.4; set_real_ip_from 192.168.30.5; set_real_ip_from 192.168.30.10; real_ip_header X-Forwarded-For; #charset koi8-r; access_log /var/log/nginx/host.access.log main; root /var/www/html; index index.php index.html index.htm; location =/memcache { rewrite ^/(.*)$ https://$server_name$request_uri? permanent; } location /accounts { rewrite ^/(.*)$ https://$server_name$request_uri? permanent; } #error_page 404 /404.html; # redirect server error pages to the static page /50x.html # error_page 500 502 503 504 /50x.html; location = /50x.html { } # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000 # location ~ \.php$ { fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; include /etc/nginx/fastcgi_params; try_files $uri = 404; } # deny access to .htaccess files, if Apache's document root # concurs with nginx's one # location ~ /\.ht { deny all; } } conf.d/ssl.conf: # HTTPS server # server { listen 443; server_name <redacted>.net; rewrite ^(.*) https://www.<redacted>.net$1; } server { listen 443 default_server ssl; server_name www.<redacted>.net; set_real_ip_from 192.168.30.4; set_real_ip_from 192.168.30.5; set_real_ip_from 192.168.30.10; real_ip_header X-Forwarded-For; proxy_set_header X-Forwarded_Proto https; proxy_set_header Host $host; proxy_redirect off; proxy_max_temp_file_size 0; proxy_set_header X-Forwarded-Ssl on; set $https_enabled on; ssl_certificate <redacted>.crt; ssl_certificate_key <redacted>.key; ssl_session_timeout 5m; ssl_protocols SSLv2 SSLv3 TLSv1; ssl_ciphers HIGH:!aNULL:!MD5; ssl_prefer_server_ciphers on; root /var/www/html; index index.php index.html index.htm; location /memcache { auth_basic "Restricted"; auth_basic_user_file $document_root/memcache/.htpasswd; } location ~ \.php$ { fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; fastcgi_param HTTPS on; include /etc/nginx/fastcgi_params; try_files $uri = 404; } }

    Read the article

  • 5x5 matrix multiplication in C

    - by Rick
    I am stuck on this problem in my homework. I've made it this far and am sure the problem is in my three for loops. The question directly says to use 3 for loops so I know this is probably just a logic error. #include<stdio.h> void matMult(int A[][5],int B[][5],int C[][5]); int printMat_5x5(int A[5][5]); int main() { int A[5][5] = {{1,2,3,4,6}, {6,1,5,3,8}, {2,6,4,9,9}, {1,3,8,3,4}, {5,7,8,2,5}}; int B[5][5] = {{3,5,0,8,7}, {2,2,4,8,3}, {0,2,5,1,2}, {1,4,0,5,1}, {3,4,8,2,3}}; int C[5][5] = {0}; matMult(A,B,C); printMat_5x5(A); printf("\n"); printMat_5x5(B); printf("\n"); printMat_5x5(C); return 0; } void matMult(int A[][5], int B[][5], int C[][5]) { int i; int j; int k; for(i = 0; i <= 2; i++) { for(j = 0; j <= 4; j++) { for(k = 0; k <= 3; k++) { C[i][j] += A[i][k] * B[k][j]; } } } } int printMat_5x5(int A[5][5]){ int i; int j; for (i = 0;i < 5;i++) { for(j = 0;j < 5;j++) { printf("%2d",A[i][j]); } printf("\n"); } } EDIT: Here is the question, sorry for not posting it the first time. (2) Write a C function to multiply two five by five matrices. The prototype should read void matMult(int a[][5],int b[][5],int c[][5]); The resulting matrix product (a times b) is returned in the two dimensional array c (the third parameter of the function). Program your solution using three nested for loops (each generating the counter values 0, 1, 2, 3, 4) That is, DO NOT code specific formulas for the 5 by 5 case in the problem, but make your code general so it can be easily changed to compute the product of larger square matrices. Write a main program to test your function using the arrays a: 1 2 3 4 6 6 1 5 3 8 2 6 4 9 9 1 3 8 3 4 5 7 8 2 5 b: 3 5 0 8 7 2 2 4 8 3 0 2 5 1 2 1 4 0 5 1 3 4 8 2 3 Print your matrices in a neat format using a C function created for printing five by five matrices. Print all three matrices. Generate your test arrays in your main program using the C array initialization feature. enter code here

    Read the article

  • Python: Improving long cumulative sum

    - by Bo102010
    I have a program that operates on a large set of experimental data. The data is stored as a list of objects that are instances of a class with the following attributes: time_point - the time of the sample cluster - the name of the cluster of nodes from which the sample was taken code - the name of the node from which the sample was taken qty1 = the value of the sample for the first quantity qty2 = the value of the sample for the second quantity I need to derive some values from the data set, grouped in three ways - once for the sample as a whole, once for each cluster of nodes, and once for each node. The values I need to derive depend on the (time sorted) cumulative sums of qty1 and qty2: the maximum value of the element-wise sum of the cumulative sums of qty1 and qty2, the time point at which that maximum value occurred, and the values of qty1 and qty2 at that time point. I came up with the following solution: dataset.sort(key=operator.attrgetter('time_point')) # For the whole set sys_qty1 = 0 sys_qty2 = 0 sys_combo = 0 sys_max = 0 # For the cluster grouping cluster_qty1 = defaultdict(int) cluster_qty2 = defaultdict(int) cluster_combo = defaultdict(int) cluster_max = defaultdict(int) cluster_peak = defaultdict(int) # For the node grouping node_qty1 = defaultdict(int) node_qty2 = defaultdict(int) node_combo = defaultdict(int) node_max = defaultdict(int) node_peak = defaultdict(int) for t in dataset: # For the whole system ###################################################### sys_qty1 += t.qty1 sys_qty2 += t.qty2 sys_combo = sys_qty1 + sys_qty2 if sys_combo > sys_max: sys_max = sys_combo # The Peak class is to record the time point and the cumulative quantities system_peak = Peak(time_point=t.time_point, qty1=sys_qty1, qty2=sys_qty2) # For the cluster grouping ################################################## cluster_qty1[t.cluster] += t.qty1 cluster_qty2[t.cluster] += t.qty2 cluster_combo[t.cluster] = cluster_qty1[t.cluster] + cluster_qty2[t.cluster] if cluster_combo[t.cluster] > cluster_max[t.cluster]: cluster_max[t.cluster] = cluster_combo[t.cluster] cluster_peak[t.cluster] = Peak(time_point=t.time_point, qty1=cluster_qty1[t.cluster], qty2=cluster_qty2[t.cluster]) # For the node grouping ##################################################### node_qty1[t.node] += t.qty1 node_qty2[t.node] += t.qty2 node_combo[t.node] = node_qty1[t.node] + node_qty2[t.node] if node_combo[t.node] > node_max[t.node]: node_max[t.node] = node_combo[t.node] node_peak[t.node] = Peak(time_point=t.time_point, qty1=node_qty1[t.node], qty2=node_qty2[t.node]) This produces the correct output, but I'm wondering if it can be made more readable/Pythonic, and/or faster/more scalable. The above is attractive in that it only loops through the (large) dataset once, but unattractive in that I've essentially copied/pasted three copies of the same algorithm. To avoid the copy/paste issues of the above, I tried this also: def find_peaks(level, dataset): def grouping(object, attr_name): if attr_name == 'system': return attr_name else: return object.__dict__[attrname] cuml_qty1 = defaultdict(int) cuml_qty2 = defaultdict(int) cuml_combo = defaultdict(int) level_max = defaultdict(int) level_peak = defaultdict(int) for t in dataset: cuml_qty1[grouping(t, level)] += t.qty1 cuml_qty2[grouping(t, level)] += t.qty2 cuml_combo[grouping(t, level)] = (cuml_qty1[grouping(t, level)] + cuml_qty2[grouping(t, level)]) if cuml_combo[grouping(t, level)] > level_max[grouping(t, level)]: level_max[grouping(t, level)] = cuml_combo[grouping(t, level)] level_peak[grouping(t, level)] = Peak(time_point=t.time_point, qty1=node_qty1[grouping(t, level)], qty2=node_qty2[grouping(t, level)]) return level_peak system_peak = find_peaks('system', dataset) cluster_peak = find_peaks('cluster', dataset) node_peak = find_peaks('node', dataset) For the (non-grouped) system-level calculations, I also came up with this, which is pretty: dataset.sort(key=operator.attrgetter('time_point')) def cuml_sum(seq): rseq = [] t = 0 for i in seq: t += i rseq.append(t) return rseq time_get = operator.attrgetter('time_point') q1_get = operator.attrgetter('qty1') q2_get = operator.attrgetter('qty2') timeline = [time_get(t) for t in dataset] cuml_qty1 = cuml_sum([q1_get(t) for t in dataset]) cuml_qty2 = cuml_sum([q2_get(t) for t in dataset]) cuml_combo = [q1 + q2 for q1, q2 in zip(cuml_qty1, cuml_qty2)] combo_max = max(cuml_combo) time_max = timeline.index(combo_max) q1_at_max = cuml_qty1.index(time_max) q2_at_max = cuml_qty2.index(time_max) However, despite this version's cool use of list comprehensions and zip(), it loops through the dataset three times just for the system-level calculations, and I can't think of a good way to do the cluster-level and node-level calaculations without doing something slow like: timeline = defaultdict(int) cuml_qty1 = defaultdict(int) #...etc. for c in cluster_list: timeline[c] = [time_get(t) for t in dataset if t.cluster == c] cuml_qty1[c] = [q1_get(t) for t in dataset if t.cluster == c] #...etc. Does anyone here at Stack Overflow have suggestions for improvements? The first snippet above runs well for my initial dataset (on the order of a million records), but later datasets will have more records and clusters/nodes, so scalability is a concern. This is my first non-trivial use of Python, and I want to make sure I'm taking proper advantage of the language (this is replacing a very convoluted set of SQL queries, and earlier versions of the Python version were essentially very ineffecient straight transalations of what that did). I don't normally do much programming, so I may be missing something elementary. Many thanks!

    Read the article

  • Minimum-Waste Print Job Grouping Algorithm?

    - by Matt Mc
    I work at a publishing house and I am setting up one of our presses for "ganging", in other words, printing multiple jobs simultaneously. Given that different print jobs can have different quantities, and anywhere from 1 to 20 jobs might need to be considered at a time, the problem would be to determine which jobs to group together to minimize waste (waste coming from over-printing on smaller-quantity jobs in a given set, that is). Given the following stable data: All jobs are equal in terms of spatial size--placement on paper doesn't come into consideration. There are three "lanes", meaning that three jobs can be printed simultaneously. Ideally, each lane has one job. Part of the problem is minimizing how many lanes each job is run on. If necessary, one job could be run on two lanes, with a second job on the third lane. The "grouping" waste from a given set of jobs (let's say the quantities of them are x, y and z) would be the highest number minus the two lower numbers. So if x is the higher number, the grouping waste would be (x - y) + (x - z). Otherwise stated, waste is produced by printing job Y and Z (in excess of their quantities) up to the quantity of X. The grouping waste would be a qualifier for the given set, meaning it could not exceed a certain quantity or the job would simply be printed alone. So the question is stated: how to determine which sets of jobs are grouped together, out of any given number of jobs, based on the qualifiers of 1) Three similar quantities OR 2) Two quantities where one is approximately double the other, AND with the aim of minimal total grouping waste across the various sets. (Edit) Quantity Information: Typical job quantities can be from 150 to 350 on foreign languages, or 500 to 1000 on English print runs. This data can be used to set up some scenarios for an algorithm. For example, let's say you had 5 jobs: 1000, 500, 500, 450, 250 By looking at it, I can see a couple of answers. Obviously (1000/500/500) is not efficient as you'll have a grouping waste of 1000. (500/500/450) is better as you'll have a waste of 50, but then you run (1000) and (250) alone. But you could also run (1000/500) with 1000 on two lanes, (500/250) with 500 on two lanes and then (450) alone. In terms of trade-offs for lane minimization vs. wastage, we could say that any grouping waste over 200 is excessive. (End Edit) ...Needless to say, quite a problem. (For me.) I am a moderately skilled programmer but I do not have much familiarity with algorithms and I am not fully studied in the mathematics of the area. I'm I/P writing a sort of brute-force program that simply tries all options, neglecting any option tree that seems to have excessive grouping waste. However, I can't help but hope there's an easier and more efficient method. I've looked at various websites trying to find out more about algorithms in general and have been slogging my way through the symbology, but it's slow going. Unfortunately, Wikipedia's articles on the subject are very cross-dependent and it's difficult to find an "in". The only thing I've been able to really find would seem to be a definition of the rough type of algorithm I need: "Exclusive Distance Clustering", one-dimensionally speaking. I did look at what seems to be the popularly referred-to algorithm on this site, the Bin Packing one, but I was unable to see exactly how it would work with my problem. Any help is appreciated. :)

    Read the article

  • Explain the Peak and Flag Algorithm

    - by Isaac Levin
    EDIT Just was pointed that the requirements state peaks cannot be ends of Arrays. So I ran across this site http://codility.com/ Which gives you programming problems and gives you certificates if you can solve them in 2 hours. The very first question is one I have seen before, typically called the Peaks and Flags question. If you are not familiar A non-empty zero-indexed array A consisting of N integers is given. A peak is an array element which is larger than its neighbours. More precisely, it is an index P such that 0 < P < N - 1 and A[P - 1] < A[P] A[P + 1] . For example, the following array A: A[0] = 1 A[1] = 5 A[2] = 3 A[3] = 4 A[4] = 3 A[5] = 4 A[6] = 1 A[7] = 2 A[8] = 3 A[9] = 4 A[10] = 6 A[11] = 2 has exactly four peaks: elements 1, 3, 5 and 10. You are going on a trip to a range of mountains whose relative heights are represented by array A. You have to choose how many flags you should take with you. The goal is to set the maximum number of flags on the peaks, according to certain rules. Flags can only be set on peaks. What's more, if you take K flags, then the distance between any two flags should be greater than or equal to K. The distance between indices P and Q is the absolute value |P - Q|. For example, given the mountain range represented by array A, above, with N = 12, if you take: two flags, you can set them on peaks 1 and 5; three flags, you can set them on peaks 1, 5 and 10; four flags, you can set only three flags, on peaks 1, 5 and 10. You can therefore set a maximum of three flags in this case. Write a function that, given a non-empty zero-indexed array A of N integers, returns the maximum number of flags that can be set on the peaks of the array. For example, given the array above the function should return 3, as explained above. Assume that: N is an integer within the range [1..100,000]; each element of array A is an integer within the range [0..1,000,000,000]. Complexity: expected worst-case time complexity is O(N); expected worst-case space complexity is O(N), beyond input storage (not counting the storage required for input arguments). Elements of input arrays can be modified. So this makes sense, but I failed it using this code public int GetFlags(int[] A) { List<int> peakList = new List<int>(); for (int i = 0; i <= A.Length - 1; i++) { if ((A[i] > A[i + 1] && A[i] > A[i - 1])) { peakList.Add(i); } } List<int> flagList = new List<int>(); int distance = peakList.Count; flagList.Add(peakList[0]); for (int i = 1, j = 0, max = peakList.Count; i < max; i++) { if (Math.Abs(Convert.ToDecimal(peakList[j]) - Convert.ToDecimal(peakList[i])) >= distance) { flagList.Add(peakList[i]); j = i; } } return flagList.Count; } EDIT int[] A = new int[] { 7, 10, 4, 5, 7, 4, 6, 1, 4, 3, 3, 7 }; The correct answer is 3, but my application says 2 This I do not get, since there are 4 peaks (indices 1,4,6,8) and from that, you should be able to place a flag at 2 of the peaks (1 and 6) Am I missing something here? Obviously my assumption is that the beginning or end of an Array can be a peak, is this not the case? If this needs to go in Stack Exchange Programmers, I will move it, but thought dialog here would be helpful. EDIT

    Read the article

  • Duplication of menu items with ViewPager and Fragments

    - by Julian
    I'm building an Android Application (minimum SDK Level 10, Gingerbread 2.3.3) with some Fragments in a ViewPager. I'm using ActionBarSherlock to create an ActionBar and android-viewpagertabs to add tabs to the ViewPager just like in the Market client. I have one global menu item that I want to be shown on every tab/fragment. On the first of the three tabs I want to have two additional menu items. But now two strange things happen: First if I start the app, everything seems to be fine, I can see all three menu items on the first page and only one item if i swipe to the second and third tab. But if I swipe back to the second tab from the third one, I can see all three items again which shouldn't happen. If I swipe back to the first and then again to the second tab, everything is fine again. The other strange thing is that every time I rotate the device, the menu items from the fragment are added again, even though they are already in the menu. Code of the FragmentActivity that displays the ViewPager and its tabs: public class MainActivity extends FragmentActivity { public static final String TAG = "MainActivity"; private ActionBar actionBar; private Adapter adapter; private ViewPager viewPager; private ViewPagerTabs tabs; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.volksempfaenger); actionBar = getSupportActionBar(); adapter = new Adapter(getSupportFragmentManager()); adapter.addFragment(getString(R.string.title_tab_subscriptions), SubscriptionGridFragment.class); // adding more fragments here viewPager = (ViewPager) findViewById(R.id.viewpager); viewPager.setAdapter(adapter); tabs = (ViewPagerTabs) findViewById(R.id.tabs); tabs.setViewPager(viewPager); } public static class Adapter extends FragmentPagerAdapter implements ViewPagerTabProvider { private FragmentManager fragmentManager; private ArrayList<Class<? extends Fragment>> fragments; private ArrayList<String> titles; public Adapter(FragmentManager fm) { super(fm); fragmentManager = fm; fragments = new ArrayList<Class<? extends Fragment>>(); titles = new ArrayList<String>(); } public void addFragment(String title, Class<? extends Fragment> fragment) { titles.add(title); fragments.add(fragment); } @Override public int getCount() { return fragments.size(); } public String getTitle(int position) { return titles.get(position); } @Override public Fragment getItem(int position) { try { return fragments.get(position).newInstance(); } catch (InstantiationException e) { Log.wtf(TAG, e); } catch (IllegalAccessException e) { Log.wtf(TAG, e); } return null; } @Override public Object instantiateItem(View container, int position) { FragmentTransaction fragmentTransaction = fragmentManager .beginTransaction(); Fragment f = getItem(position); fragmentTransaction.add(container.getId(), f); fragmentTransaction.commit(); return f; } } @Override public boolean onCreateOptionsMenu(Menu menu) { BaseActivity.addGlobalMenu(this, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { return BaseActivity.handleGlobalMenu(this, item); } } Code of the fragment that shall have its own menu items: public class SubscriptionGridFragment extends Fragment { private GridView subscriptionList; private SubscriptionListAdapter adapter; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setHasOptionsMenu(true); } // ... @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { inflater.inflate(R.menu.subscription_list, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // ... } }

    Read the article

  • What can I do to improve a project if there is a no-listening situation. Developers vs Management

    - by NazGul
    Hi all, I hope that I'm not the only one and I can get a answer from someone with more experience than me, so I can think cleaner and I don't get depressed with this developer's life. I'm working as developer for a small company three years now. In that three years I'm working in the same project and sincerely, I think this project could be used as a CASE STUDY because it has all the situations that cannot happen in a project and that makes a project fails. To begin with, and I believe you've already noticed, the project has 3 years already (develoment only) and is still unfinished, because in every meeting there is a "new priority" ,or a "new problem" to be solve or a "new feature" to be add. So, first problem is no target set. How can you know when something is finished if you don't know what you want? I understand Management, because they see an oportunity and try to get that, but I don't understand how can they not see (or hear us) that they'll lose all they already have and what they'll eventually get. Second, there is no team group. My team consists of three people, a Senior Developer, a DBA and, finally, I for all the work (support, testing, new features, bug fixing, meeting, projet management of clients, etc) aka Junior Developer. The first (senior developer), does not perform any tests on his changes, so, most of the time, his changes give us problems (us = me, since I'm the one who will fix it). The second (DBA) is an uncompromising person and you can not talk to him, believe me, I tried! In his view, everything he does is fantastic... even if it is the most complicated to make it... And he does everything he wants, even if we need that only for 5 months later and would help some extra-hand to do the things we have to do for now. As you can see, there is very hard to work with no help... Third, there is no testings. Every... I repeat, Every release of the project, the customers wants to kill us, because there is a lot of bugs. Management? They say that they want tests before the release. Us? We say the same. Time? No time. Management? There is always some time to open the application and click in some buttons. Us? Try to explain that it is not so simple. Management doesn't care... end of story. Actually, must of the bugs could be avoid with a rigorous work... Some people just want to do the show to the Management. "Did you ask for this? Cool, it's done. Bugs? The Do-all-the-work guy will solve." Unfortunally for me, sometimes the Do-all-the-work also has to finish it. And to makes this all better, I'm the person who will listen the complaints from the customers. Cool, huh? I know, everyone makes mistakes. But there is mistakes and mistakes... To complete, in the Management view, "the problem is the lack of an individual project management", because we cannot do all the stuff they ask, even if there is no PM for the project itself. And ask us to work overtime without any reward... I do say all this stuff to the management and others members, but by telling this, the I'm the bad guy, the guy who is complain when everything is going well... but we need to work overtime... sigh What can I do to make it works? Anyone has a situation like this, what did you do? I hope you could understand my problem, my English is a little rusty. Thanks.

    Read the article

  • Selecting unique records in XSLT/XPath

    - by Daniel I-S
    I have to select only unique records from an XML document, in the context of an <xsl:for-each> loop. I am limited by Visual Studio to using XSL 1.0. <availList> <item> <schDate>2010-06-24</schDate> <schFrmTime>10:00:00</schFrmTime> <schToTime>13:00:00</schToTime> <variousOtherElements></variousOtherElements> </item> <item> <schDate>2010-06-24</schDate> <schFrmTime>10:00:00</schFrmTime> <schToTime>13:00:00</schToTime> <variousOtherElements></variousOtherElements> </item> <item> <schDate>2010-06-25</schDate> <schFrmTime>10:00:00</schFrmTime> <schToTime>12:00:00</schToTime> <variousOtherElements></variousOtherElements> </item> <item> <schDate>2010-06-26</schDate> <schFrmTime>13:00:00</schFrmTime> <schToTime>14:00:00</schToTime> <variousOtherElements></variousOtherElements> </item> <item> <schDate>2010-06-26</schDate> <schFrmTime>10:00:00</schFrmTime> <schToTime>12:00:00</schToTime> <variousOtherElements></variousOtherElements> </item> </availList> The uniqueness must be based on the value of the three child elements: schDate, schFrmTime and schToTime. If two item elements have the same values for all three child elements, they are duplicates. In the above XML, items one and two are duplicates. The rest are unique. As indicated above, each item contains other elements that we do not wish to include in the comparison. 'Uniqueness' should be a factor of those three elements, and those alone. I have attempted to accomplish this through the following: availList/item[not(schDate = preceding:: schDate and schFrmTime = preceding:: schFrmTime and schToTime = preceding:: schToTime)] The idea behind this is to select records where there is no preceding element with the same schDate, schFrmTime and schToTime. However, its output is missing the last item. This is because my XPath is actually excluding items where all of the child element values are matched within the entire preceding document. No single item matches all of the last item's child elements - but because each element's value is individually present in another item, the last item gets excluded. I could get the correct result by comparing all child values as a concatenated string to the same concatenated values for each preceding item. Does anybody know of a way I could do this?

    Read the article

  • Zen and the Art of File and Folder Organization

    - by Mark Virtue
    Is your desk a paragon of neatness, or does it look like a paper-bomb has gone off? If you’ve been putting off getting organized because the task is too huge or daunting, or you don’t know where to start, we’ve got 40 tips to get you on the path to zen mastery of your filing system. For all those readers who would like to get their files and folders organized, or, if they’re already organized, better organized—we have compiled a complete guide to getting organized and staying organized, a comprehensive article that will hopefully cover every possible tip you could want. Signs that Your Computer is Poorly Organized If your computer is a mess, you’re probably already aware of it.  But just in case you’re not, here are some tell-tale signs: Your Desktop has over 40 icons on it “My Documents” contains over 300 files and 60 folders, including MP3s and digital photos You use the Windows’ built-in search facility whenever you need to find a file You can’t find programs in the out-of-control list of programs in your Start Menu You save all your Word documents in one folder, all your spreadsheets in a second folder, etc Any given file that you’re looking for may be in any one of four different sets of folders But before we start, here are some quick notes: We’re going to assume you know what files and folders are, and how to create, save, rename, copy and delete them The organization principles described in this article apply equally to all computer systems.  However, the screenshots here will reflect how things look on Windows (usually Windows 7).  We will also mention some useful features of Windows that can help you get organized. Everyone has their own favorite methodology of organizing and filing, and it’s all too easy to get into “My Way is Better than Your Way” arguments.  The reality is that there is no perfect way of getting things organized.  When I wrote this article, I tried to keep a generalist and objective viewpoint.  I consider myself to be unusually well organized (to the point of obsession, truth be told), and I’ve had 25 years experience in collecting and organizing files on computers.  So I’ve got a lot to say on the subject.  But the tips I have described here are only one way of doing it.  Hopefully some of these tips will work for you too, but please don’t read this as any sort of “right” way to do it. At the end of the article we’ll be asking you, the reader, for your own organization tips. Why Bother Organizing At All? For some, the answer to this question is self-evident. And yet, in this era of powerful desktop search software (the search capabilities built into the Windows Vista and Windows 7 Start Menus, and third-party programs like Google Desktop Search), the question does need to be asked, and answered. I have a friend who puts every file he ever creates, receives or downloads into his My Documents folder and doesn’t bother filing them into subfolders at all.  He relies on the search functionality built into his Windows operating system to help him find whatever he’s looking for.  And he always finds it.  He’s a Search Samurai.  For him, filing is a waste of valuable time that could be spent enjoying life! It’s tempting to follow suit.  On the face of it, why would anyone bother to take the time to organize their hard disk when such excellent search software is available?  Well, if all you ever want to do with the files you own is to locate and open them individually (for listening, editing, etc), then there’s no reason to ever bother doing one scrap of organization.  But consider these common tasks that are not achievable with desktop search software: Find files manually.  Often it’s not convenient, speedy or even possible to utilize your desktop search software to find what you want.  It doesn’t work 100% of the time, or you may not even have it installed.  Sometimes its just plain faster to go straight to the file you want, if you know it’s in a particular sub-folder, rather than trawling through hundreds of search results. Find groups of similar files (e.g. all your “work” files, all the photos of your Europe holiday in 2008, all your music videos, all the MP3s from Dark Side of the Moon, all your letters you wrote to your wife, all your tax returns).  Clever naming of the files will only get you so far.  Sometimes it’s the date the file was created that’s important, other times it’s the file format, and other times it’s the purpose of the file.  How do you name a collection of files so that they’re easy to isolate based on any of the above criteria?  Short answer, you can’t. Move files to a new computer.  It’s time to upgrade your computer.  How do you quickly grab all the files that are important to you?  Or you decide to have two computers now – one for home and one for work.  How do you quickly isolate only the work-related files to move them to the work computer? Synchronize files to other computers.  If you have more than one computer, and you need to mirror some of your files onto the other computer (e.g. your music collection), then you need a way to quickly determine which files are to be synced and which are not.  Surely you don’t want to synchronize everything? Choose which files to back up.  If your backup regime calls for multiple backups, or requires speedy backups, then you’ll need to be able to specify which files are to be backed up, and which are not.  This is not possible if they’re all in the same folder. Finally, if you’re simply someone who takes pleasure in being organized, tidy and ordered (me! me!), then you don’t even need a reason.  Being disorganized is simply unthinkable. Tips on Getting Organized Here we present our 40 best tips on how to get organized.  Or, if you’re already organized, to get better organized. Tip #1.  Choose Your Organization System Carefully The reason that most people are not organized is that it takes time.  And the first thing that takes time is deciding upon a system of organization.  This is always a matter of personal preference, and is not something that a geek on a website can tell you.  You should always choose your own system, based on how your own brain is organized (which makes the assumption that your brain is, in fact, organized). We can’t instruct you, but we can make suggestions: You may want to start off with a system based on the users of the computer.  i.e. “My Files”, “My Wife’s Files”, My Son’s Files”, etc.  Inside “My Files”, you might then break it down into “Personal” and “Business”.  You may then realize that there are overlaps.  For example, everyone may want to share access to the music library, or the photos from the school play.  So you may create another folder called “Family”, for the “common” files. You may decide that the highest-level breakdown of your files is based on the “source” of each file.  In other words, who created the files.  You could have “Files created by ME (business or personal)”, “Files created by people I know (family, friends, etc)”, and finally “Files created by the rest of the world (MP3 music files, downloaded or ripped movies or TV shows, software installation files, gorgeous desktop wallpaper images you’ve collected, etc).”  This system happens to be the one I use myself.  See below:  Mark is for files created by meVC is for files created by my company (Virtual Creations)Others is for files created by my friends and familyData is the rest of the worldAlso, Settings is where I store the configuration files and other program data files for my installed software (more on this in tip #34, below). Each folder will present its own particular set of requirements for further sub-organization.  For example, you may decide to organize your music collection into sub-folders based on the artist’s name, while your digital photos might get organized based on the date they were taken.  It can be different for every sub-folder! Another strategy would be based on “currentness”.  Files you have yet to open and look at live in one folder.  Ones that have been looked at but not yet filed live in another place.  Current, active projects live in yet another place.  All other files (your “archive”, if you like) would live in a fourth folder. (And of course, within that last folder you’d need to create a further sub-system based on one of the previous bullet points). Put some thought into this – changing it when it proves incomplete can be a big hassle!  Before you go to the trouble of implementing any system you come up with, examine a wide cross-section of the files you own and see if they will all be able to find a nice logical place to sit within your system. Tip #2.  When You Decide on Your System, Stick to It! There’s nothing more pointless than going to all the trouble of creating a system and filing all your files, and then whenever you create, receive or download a new file, you simply dump it onto your Desktop.  You need to be disciplined – forever!  Every new file you get, spend those extra few seconds to file it where it belongs!  Otherwise, in just a month or two, you’ll be worse off than before – half your files will be organized and half will be disorganized – and you won’t know which is which! Tip #3.  Choose the Root Folder of Your Structure Carefully Every data file (document, photo, music file, etc) that you create, own or is important to you, no matter where it came from, should be found within one single folder, and that one single folder should be located at the root of your C: drive (as a sub-folder of C:\).  In other words, do not base your folder structure in standard folders like “My Documents”.  If you do, then you’re leaving it up to the operating system engineers to decide what folder structure is best for you.  And every operating system has a different system!  In Windows 7 your files are found in C:\Users\YourName, whilst on Windows XP it was C:\Documents and Settings\YourName\My Documents.  In UNIX systems it’s often /home/YourName. These standard default folders tend to fill up with junk files and folders that are not at all important to you.  “My Documents” is the worst offender.  Every second piece of software you install, it seems, likes to create its own folder in the “My Documents” folder.  These folders usually don’t fit within your organizational structure, so don’t use them!  In fact, don’t even use the “My Documents” folder at all.  Allow it to fill up with junk, and then simply ignore it.  It sounds heretical, but: Don’t ever visit your “My Documents” folder!  Remove your icons/links to “My Documents” and replace them with links to the folders you created and you care about! Create your own file system from scratch!  Probably the best place to put it would be on your D: drive – if you have one.  This way, all your files live on one drive, while all the operating system and software component files live on the C: drive – simply and elegantly separated.  The benefits of that are profound.  Not only are there obvious organizational benefits (see tip #10, below), but when it comes to migrate your data to a new computer, you can (sometimes) simply unplug your D: drive and plug it in as the D: drive of your new computer (this implies that the D: drive is actually a separate physical disk, and not a partition on the same disk as C:).  You also get a slight speed improvement (again, only if your C: and D: drives are on separate physical disks). Warning:  From tip #12, below, you will see that it’s actually a good idea to have exactly the same file system structure – including the drive it’s filed on – on all of the computers you own.  So if you decide to use the D: drive as the storage system for your own files, make sure you are able to use the D: drive on all the computers you own.  If you can’t ensure that, then you can still use a clever geeky trick to store your files on the D: drive, but still access them all via the C: drive (see tip #17, below). If you only have one hard disk (C:), then create a dedicated folder that will contain all your files – something like C:\Files.  The name of the folder is not important, but make it a single, brief word. There are several reasons for this: When creating a backup regime, it’s easy to decide what files should be backed up – they’re all in the one folder! If you ever decide to trade in your computer for a new one, you know exactly which files to migrate You will always know where to begin a search for any file If you synchronize files with other computers, it makes your synchronization routines very simple.   It also causes all your shortcuts to continue to work on the other machines (more about this in tip #24, below). Once you’ve decided where your files should go, then put all your files in there – Everything!  Completely disregard the standard, default folders that are created for you by the operating system (“My Music”, “My Pictures”, etc).  In fact, you can actually relocate many of those folders into your own structure (more about that below, in tip #6). The more completely you get all your data files (documents, photos, music, etc) and all your configuration settings into that one folder, then the easier it will be to perform all of the above tasks. Once this has been done, and all your files live in one folder, all the other folders in C:\ can be thought of as “operating system” folders, and therefore of little day-to-day interest for us. Here’s a screenshot of a nicely organized C: drive, where all user files are located within the \Files folder:   Tip #4.  Use Sub-Folders This would be our simplest and most obvious tip.  It almost goes without saying.  Any organizational system you decide upon (see tip #1) will require that you create sub-folders for your files.  Get used to creating folders on a regular basis. Tip #5.  Don’t be Shy About Depth Create as many levels of sub-folders as you need.  Don’t be scared to do so.  Every time you notice an opportunity to group a set of related files into a sub-folder, do so.  Examples might include:  All the MP3s from one music CD, all the photos from one holiday, or all the documents from one client. It’s perfectly okay to put files into a folder called C:\Files\Me\From Others\Services\WestCo Bank\Statements\2009.  That’s only seven levels deep.  Ten levels is not uncommon.  Of course, it’s possible to take this too far.  If you notice yourself creating a sub-folder to hold only one file, then you’ve probably become a little over-zealous.  On the other hand, if you simply create a structure with only two levels (for example C:\Files\Work) then you really haven’t achieved any level of organization at all (unless you own only six files!).  Your “Work” folder will have become a dumping ground, just like your Desktop was, with most likely hundreds of files in it. Tip #6.  Move the Standard User Folders into Your Own Folder Structure Most operating systems, including Windows, create a set of standard folders for each of its users.  These folders then become the default location for files such as documents, music files, digital photos and downloaded Internet files.  In Windows 7, the full list is shown below: Some of these folders you may never use nor care about (for example, the Favorites folder, if you’re not using Internet Explorer as your browser).  Those ones you can leave where they are.  But you may be using some of the other folders to store files that are important to you.  Even if you’re not using them, Windows will still often treat them as the default storage location for many types of files.  When you go to save a standard file type, it can become annoying to be automatically prompted to save it in a folder that’s not part of your own file structure. But there’s a simple solution:  Move the folders you care about into your own folder structure!  If you do, then the next time you go to save a file of the corresponding type, Windows will prompt you to save it in the new, moved location. Moving the folders is easy.  Simply drag-and-drop them to the new location.  Here’s a screenshot of the default My Music folder being moved to my custom personal folder (Mark): Tip #7.  Name Files and Folders Intelligently This is another one that almost goes without saying, but we’ll say it anyway:  Do not allow files to be created that have meaningless names like Document1.doc, or folders called New Folder (2).  Take that extra 20 seconds and come up with a meaningful name for the file/folder – one that accurately divulges its contents without repeating the entire contents in the name. Tip #8.  Watch Out for Long Filenames Another way to tell if you have not yet created enough depth to your folder hierarchy is that your files often require really long names.  If you need to call a file Johnson Sales Figures March 2009.xls (which might happen to live in the same folder as Abercrombie Budget Report 2008.xls), then you might want to create some sub-folders so that the first file could be simply called March.xls, and living in the Clients\Johnson\Sales Figures\2009 folder. A well-placed file needs only a brief filename! Tip #9.  Use Shortcuts!  Everywhere! This is probably the single most useful and important tip we can offer.  A shortcut allows a file to be in two places at once. Why would you want that?  Well, the file and folder structure of every popular operating system on the market today is hierarchical.  This means that all objects (files and folders) always live within exactly one parent folder.  It’s a bit like a tree.  A tree has branches (folders) and leaves (files).  Each leaf, and each branch, is supported by exactly one parent branch, all the way back to the root of the tree (which, incidentally, is exactly why C:\ is called the “root folder” of the C: drive). That hard disks are structured this way may seem obvious and even necessary, but it’s only one way of organizing data.  There are others:  Relational databases, for example, organize structured data entirely differently.  The main limitation of hierarchical filing structures is that a file can only ever be in one branch of the tree – in only one folder – at a time.  Why is this a problem?  Well, there are two main reasons why this limitation is a problem for computer users: The “correct” place for a file, according to our organizational rationale, is very often a very inconvenient place for that file to be located.  Just because it’s correctly filed doesn’t mean it’s easy to get to.  Your file may be “correctly” buried six levels deep in your sub-folder structure, but you may need regular and speedy access to this file every day.  You could always move it to a more convenient location, but that would mean that you would need to re-file back to its “correct” location it every time you’d finished working on it.  Most unsatisfactory. A file may simply “belong” in two or more different locations within your file structure.  For example, say you’re an accountant and you have just completed the 2009 tax return for John Smith.  It might make sense to you to call this file 2009 Tax Return.doc and file it under Clients\John Smith.  But it may also be important to you to have the 2009 tax returns from all your clients together in the one place.  So you might also want to call the file John Smith.doc and file it under Tax Returns\2009.  The problem is, in a purely hierarchical filing system, you can’t put it in both places.  Grrrrr! Fortunately, Windows (and most other operating systems) offers a way for you to do exactly that:  It’s called a “shortcut” (also known as an “alias” on Macs and a “symbolic link” on UNIX systems).  Shortcuts allow a file to exist in one place, and an icon that represents the file to be created and put anywhere else you please.  In fact, you can create a dozen such icons and scatter them all over your hard disk.  Double-clicking on one of these icons/shortcuts opens up the original file, just as if you had double-clicked on the original file itself. Consider the following two icons: The one on the left is the actual Word document, while the one on the right is a shortcut that represents the Word document.  Double-clicking on either icon will open the same file.  There are two main visual differences between the icons: The shortcut will have a small arrow in the lower-left-hand corner (on Windows, anyway) The shortcut is allowed to have a name that does not include the file extension (the “.docx” part, in this case) You can delete the shortcut at any time without losing any actual data.  The original is still intact.  All you lose is the ability to get to that data from wherever the shortcut was. So why are shortcuts so great?  Because they allow us to easily overcome the main limitation of hierarchical file systems, and put a file in two (or more) places at the same time.  You will always have files that don’t play nice with your organizational rationale, and can’t be filed in only one place.  They demand to exist in two places.  Shortcuts allow this!  Furthermore, they allow you to collect your most often-opened files and folders together in one spot for convenient access.  The cool part is that the original files stay where they are, safe forever in their perfectly organized location. So your collection of most often-opened files can – and should – become a collection of shortcuts! If you’re still not convinced of the utility of shortcuts, consider the following well-known areas of a typical Windows computer: The Start Menu (and all the programs that live within it) The Quick Launch bar (or the Superbar in Windows 7) The “Favorite folders” area in the top-left corner of the Windows Explorer window (in Windows Vista or Windows 7) Your Internet Explorer Favorites or Firefox Bookmarks Each item in each of these areas is a shortcut!  Each of those areas exist for one purpose only:  For convenience – to provide you with a collection of the files and folders you access most often. It should be easy to see by now that shortcuts are designed for one single purpose:  To make accessing your files more convenient.  Each time you double-click on a shortcut, you are saved the hassle of locating the file (or folder, or program, or drive, or control panel icon) that it represents. Shortcuts allow us to invent a golden rule of file and folder organization: “Only ever have one copy of a file – never have two copies of the same file.  Use a shortcut instead” (this rule doesn’t apply to copies created for backup purposes, of course!) There are also lesser rules, like “don’t move a file into your work area – create a shortcut there instead”, and “any time you find yourself frustrated with how long it takes to locate a file, create a shortcut to it and place that shortcut in a convenient location.” So how to we create these massively useful shortcuts?  There are two main ways: “Copy” the original file or folder (click on it and type Ctrl-C, or right-click on it and select Copy):  Then right-click in an empty area of the destination folder (the place where you want the shortcut to go) and select Paste shortcut: Right-drag (drag with the right mouse button) the file from the source folder to the destination folder.  When you let go of the mouse button at the destination folder, a menu pops up: Select Create shortcuts here. Note that when shortcuts are created, they are often named something like Shortcut to Budget Detail.doc (windows XP) or Budget Detail – Shortcut.doc (Windows 7).   If you don’t like those extra words, you can easily rename the shortcuts after they’re created, or you can configure Windows to never insert the extra words in the first place (see our article on how to do this). And of course, you can create shortcuts to folders too, not just to files! Bottom line: Whenever you have a file that you’d like to access from somewhere else (whether it’s convenience you’re after, or because the file simply belongs in two places), create a shortcut to the original file in the new location. Tip #10.  Separate Application Files from Data Files Any digital organization guru will drum this rule into you.  Application files are the components of the software you’ve installed (e.g. Microsoft Word, Adobe Photoshop or Internet Explorer).  Data files are the files that you’ve created for yourself using that software (e.g. Word Documents, digital photos, emails or playlists). Software gets installed, uninstalled and upgraded all the time.  Hopefully you always have the original installation media (or downloaded set-up file) kept somewhere safe, and can thus reinstall your software at any time.  This means that the software component files are of little importance.  Whereas the files you have created with that software is, by definition, important.  It’s a good rule to always separate unimportant files from important files. So when your software prompts you to save a file you’ve just created, take a moment and check out where it’s suggesting that you save the file.  If it’s suggesting that you save the file into the same folder as the software itself, then definitely don’t follow that suggestion.  File it in your own folder!  In fact, see if you can find the program’s configuration option that determines where files are saved by default (if it has one), and change it. Tip #11.  Organize Files Based on Purpose, Not on File Type If you have, for example a folder called Work\Clients\Johnson, and within that folder you have two sub-folders, Word Documents and Spreadsheets (in other words, you’re separating “.doc” files from “.xls” files), then chances are that you’re not optimally organized.  It makes little sense to organize your files based on the program that created them.  Instead, create your sub-folders based on the purpose of the file.  For example, it would make more sense to create sub-folders called Correspondence and Financials.  It may well be that all the files in a given sub-folder are of the same file-type, but this should be more of a coincidence and less of a design feature of your organization system. Tip #12.  Maintain the Same Folder Structure on All Your Computers In other words, whatever organizational system you create, apply it to every computer that you can.  There are several benefits to this: There’s less to remember.  No matter where you are, you always know where to look for your files If you copy or synchronize files from one computer to another, then setting up the synchronization job becomes very simple Shortcuts can be copied or moved from one computer to another with ease (assuming the original files are also copied/moved).  There’s no need to find the target of the shortcut all over again on the second computer Ditto for linked files (e.g Word documents that link to data in a separate Excel file), playlists, and any files that reference the exact file locations of other files. This applies even to the drive that your files are stored on.  If your files are stored on C: on one computer, make sure they’re stored on C: on all your computers.  Otherwise all your shortcuts, playlists and linked files will stop working! Tip #13.  Create an “Inbox” Folder Create yourself a folder where you store all files that you’re currently working on, or that you haven’t gotten around to filing yet.  You can think of this folder as your “to-do” list.  You can call it “Inbox” (making it the same metaphor as your email system), or “Work”, or “To-Do”, or “Scratch”, or whatever name makes sense to you.  It doesn’t matter what you call it – just make sure you have one! Once you have finished working on a file, you then move it from the “Inbox” to its correct location within your organizational structure. You may want to use your Desktop as this “Inbox” folder.  Rightly or wrongly, most people do.  It’s not a bad place to put such files, but be careful:  If you do decide that your Desktop represents your “to-do” list, then make sure that no other files find their way there.  In other words, make sure that your “Inbox”, wherever it is, Desktop or otherwise, is kept free of junk – stray files that don’t belong there. So where should you put this folder, which, almost by definition, lives outside the structure of the rest of your filing system?  Well, first and foremost, it has to be somewhere handy.  This will be one of your most-visited folders, so convenience is key.  Putting it on the Desktop is a great option – especially if you don’t have any other folders on your Desktop:  the folder then becomes supremely easy to find in Windows Explorer: You would then create shortcuts to this folder in convenient spots all over your computer (“Favorite Links”, “Quick Launch”, etc). Tip #14.  Ensure You have Only One “Inbox” Folder Once you’ve created your “Inbox” folder, don’t use any other folder location as your “to-do list”.  Throw every incoming or created file into the Inbox folder as you create/receive it.  This keeps the rest of your computer pristine and free of randomly created or downloaded junk.  The last thing you want to be doing is checking multiple folders to see all your current tasks and projects.  Gather them all together into one folder. Here are some tips to help ensure you only have one Inbox: Set the default “save” location of all your programs to this folder. Set the default “download” location for your browser to this folder. If this folder is not your desktop (recommended) then also see if you can make a point of not putting “to-do” files on your desktop.  This keeps your desktop uncluttered and Zen-like: (the Inbox folder is in the bottom-right corner) Tip #15.  Be Vigilant about Clearing Your “Inbox” Folder This is one of the keys to staying organized.  If you let your “Inbox” overflow (i.e. allow there to be more than, say, 30 files or folders in there), then you’re probably going to start feeling like you’re overwhelmed:  You’re not keeping up with your to-do list.  Once your Inbox gets beyond a certain point (around 30 files, studies have shown), then you’ll simply start to avoid it.  You may continue to put files in there, but you’ll be scared to look at it, fearing the “out of control” feeling that all overworked, chaotic or just plain disorganized people regularly feel. So, here’s what you can do: Visit your Inbox/to-do folder regularly (at least five times per day). Scan the folder regularly for files that you have completed working on and are ready for filing.  File them immediately. Make it a source of pride to keep the number of files in this folder as small as possible.  If you value peace of mind, then make the emptiness of this folder one of your highest (computer) priorities If you know that a particular file has been in the folder for more than, say, six weeks, then admit that you’re not actually going to get around to processing it, and move it to its final resting place. Tip #16.  File Everything Immediately, and Use Shortcuts for Your Active Projects As soon as you create, receive or download a new file, store it away in its “correct” folder immediately.  Then, whenever you need to work on it (possibly straight away), create a shortcut to it in your “Inbox” (“to-do”) folder or your desktop.  That way, all your files are always in their “correct” locations, yet you still have immediate, convenient access to your current, active files.  When you finish working on a file, simply delete the shortcut. Ideally, your “Inbox” folder – and your Desktop – should contain no actual files or folders.  They should simply contain shortcuts. Tip #17.  Use Directory Symbolic Links (or Junctions) to Maintain One Unified Folder Structure Using this tip, we can get around a potential hiccup that we can run into when creating our organizational structure – the issue of having more than one drive on our computer (C:, D:, etc).  We might have files we need to store on the D: drive for space reasons, and yet want to base our organized folder structure on the C: drive (or vice-versa). Your chosen organizational structure may dictate that all your files must be accessed from the C: drive (for example, the root folder of all your files may be something like C:\Files).  And yet you may still have a D: drive and wish to take advantage of the hundreds of spare Gigabytes that it offers.  Did you know that it’s actually possible to store your files on the D: drive and yet access them as if they were on the C: drive?  And no, we’re not talking about shortcuts here (although the concept is very similar). By using the shell command mklink, you can essentially take a folder that lives on one drive and create an alias for it on a different drive (you can do lots more than that with mklink – for a full rundown on this programs capabilities, see our dedicated article).  These aliases are called directory symbolic links (and used to be known as junctions).  You can think of them as “virtual” folders.  They function exactly like regular folders, except they’re physically located somewhere else. For example, you may decide that your entire D: drive contains your complete organizational file structure, but that you need to reference all those files as if they were on the C: drive, under C:\Files.  If that was the case you could create C:\Files as a directory symbolic link – a link to D:, as follows: mklink /d c:\files d:\ Or it may be that the only files you wish to store on the D: drive are your movie collection.  You could locate all your movie files in the root of your D: drive, and then link it to C:\Files\Media\Movies, as follows: mklink /d c:\files\media\movies d:\ (Needless to say, you must run these commands from a command prompt – click the Start button, type cmd and press Enter) Tip #18. Customize Your Folder Icons This is not strictly speaking an organizational tip, but having unique icons for each folder does allow you to more quickly visually identify which folder is which, and thus saves you time when you’re finding files.  An example is below (from my folder that contains all files downloaded from the Internet): To learn how to change your folder icons, please refer to our dedicated article on the subject. Tip #19.  Tidy Your Start Menu The Windows Start Menu is usually one of the messiest parts of any Windows computer.  Every program you install seems to adopt a completely different approach to placing icons in this menu.  Some simply put a single program icon.  Others create a folder based on the name of the software.  And others create a folder based on the name of the software manufacturer.  It’s chaos, and can make it hard to find the software you want to run. Thankfully we can avoid this chaos with useful operating system features like Quick Launch, the Superbar or pinned start menu items. Even so, it would make a lot of sense to get into the guts of the Start Menu itself and give it a good once-over.  All you really need to decide is how you’re going to organize your applications.  A structure based on the purpose of the application is an obvious candidate.  Below is an example of one such structure: In this structure, Utilities means software whose job it is to keep the computer itself running smoothly (configuration tools, backup software, Zip programs, etc).  Applications refers to any productivity software that doesn’t fit under the headings Multimedia, Graphics, Internet, etc. In case you’re not aware, every icon in your Start Menu is a shortcut and can be manipulated like any other shortcut (copied, moved, deleted, etc). With the Windows Start Menu (all version of Windows), Microsoft has decided that there be two parallel folder structures to store your Start Menu shortcuts.  One for you (the logged-in user of the computer) and one for all users of the computer.  Having two parallel structures can often be redundant:  If you are the only user of the computer, then having two parallel structures is totally redundant.  Even if you have several users that regularly log into the computer, most of your installed software will need to be made available to all users, and should thus be moved out of the “just you” version of the Start Menu and into the “all users” area. To take control of your Start Menu, so you can start organizing it, you’ll need to know how to access the actual folders and shortcut files that make up the Start Menu (both versions of it).  To find these folders and files, click the Start button and then right-click on the All Programs text (Windows XP users should right-click on the Start button itself): The Open option refers to the “just you” version of the Start Menu, while the Open All Users option refers to the “all users” version.  Click on the one you want to organize. A Windows Explorer window then opens with your chosen version of the Start Menu selected.  From there it’s easy.  Double-click on the Programs folder and you’ll see all your folders and shortcuts.  Now you can delete/rename/move until it’s just the way you want it. Note:  When you’re reorganizing your Start Menu, you may want to have two Explorer windows open at the same time – one showing the “just you” version and one showing the “all users” version.  You can drag-and-drop between the windows. Tip #20.  Keep Your Start Menu Tidy Once you have a perfectly organized Start Menu, try to be a little vigilant about keeping it that way.  Every time you install a new piece of software, the icons that get created will almost certainly violate your organizational structure. So to keep your Start Menu pristine and organized, make sure you do the following whenever you install a new piece of software: Check whether the software was installed into the “just you” area of the Start Menu, or the “all users” area, and then move it to the correct area. Remove all the unnecessary icons (like the “Read me” icon, the “Help” icon (you can always open the help from within the software itself when it’s running), the “Uninstall” icon, the link(s)to the manufacturer’s website, etc) Rename the main icon(s) of the software to something brief that makes sense to you.  For example, you might like to rename Microsoft Office Word 2010 to simply Word Move the icon(s) into the correct folder based on your Start Menu organizational structure And don’t forget:  when you uninstall a piece of software, the software’s uninstall routine is no longer going to be able to remove the software’s icon from the Start Menu (because you moved and/or renamed it), so you’ll need to remove that icon manually. Tip #21.  Tidy C:\ The root of your C: drive (C:\) is a common dumping ground for files and folders – both by the users of your computer and by the software that you install on your computer.  It can become a mess. There’s almost no software these days that requires itself to be installed in C:\.  99% of the time it can and should be installed into C:\Program Files.  And as for your own files, well, it’s clear that they can (and almost always should) be stored somewhere else. In an ideal world, your C:\ folder should look like this (on Windows 7): Note that there are some system files and folders in C:\ that are usually and deliberately “hidden” (such as the Windows virtual memory file pagefile.sys, the boot loader file bootmgr, and the System Volume Information folder).  Hiding these files and folders is a good idea, as they need to stay where they are and are almost never needed to be opened or even seen by you, the user.  Hiding them prevents you from accidentally messing with them, and enhances your sense of order and well-being when you look at your C: drive folder. Tip #22.  Tidy Your Desktop The Desktop is probably the most abused part of a Windows computer (from an organization point of view).  It usually serves as a dumping ground for all incoming files, as well as holding icons to oft-used applications, plus some regularly opened files and folders.  It often ends up becoming an uncontrolled mess.  See if you can avoid this.  Here’s why… Application icons (Word, Internet Explorer, etc) are often found on the Desktop, but it’s unlikely that this is the optimum place for them.  The “Quick Launch” bar (or the Superbar in Windows 7) is always visible and so represents a perfect location to put your icons.  You’ll only be able to see the icons on your Desktop when all your programs are minimized.  It might be time to get your application icons off your desktop… You may have decided that the Inbox/To-do folder on your computer (see tip #13, above) should be your Desktop.  If so, then enough said.  Simply be vigilant about clearing it and preventing it from being polluted by junk files (see tip #15, above).  On the other hand, if your Desktop is not acting as your “Inbox” folder, then there’s no reason for it to have any data files or folders on it at all, except perhaps a couple of shortcuts to often-opened files and folders (either ongoing or current projects).  Everything else should be moved to your “Inbox” folder. In an ideal world, it might look like this: Tip #23.  Move Permanent Items on Your Desktop Away from the Top-Left Corner When files/folders are dragged onto your desktop in a Windows Explorer window, or when shortcuts are created on your Desktop from Internet Explorer, those icons are always placed in the top-left corner – or as close as they can get.  If you have other files, folders or shortcuts that you keep on the Desktop permanently, then it’s a good idea to separate these permanent icons from the transient ones, so that you can quickly identify which ones the transients are.  An easy way to do this is to move all your permanent icons to the right-hand side of your Desktop.  That should keep them separated from incoming items. Tip #24.  Synchronize If you have more than one computer, you’ll almost certainly want to share files between them.  If the computers are permanently attached to the same local network, then there’s no need to store multiple copies of any one file or folder – shortcuts will suffice.  However, if the computers are not always on the same network, then you will at some point need to copy files between them.  For files that need to permanently live on both computers, the ideal way to do this is to synchronize the files, as opposed to simply copying them. We only have room here to write a brief summary of synchronization, not a full article.  In short, there are several different types of synchronization: Where the contents of one folder are accessible anywhere, such as with Dropbox Where the contents of any number of folders are accessible anywhere, such as with Windows Live Mesh Where any files or folders from anywhere on your computer are synchronized with exactly one other computer, such as with the Windows “Briefcase”, Microsoft SyncToy, or (much more powerful, yet still free) SyncBack from 2BrightSparks.  This only works when both computers are on the same local network, at least temporarily. A great advantage of synchronization solutions is that once you’ve got it configured the way you want it, then the sync process happens automatically, every time.  Click a button (or schedule it to happen automatically) and all your files are automagically put where they’re supposed to be. If you maintain the same file and folder structure on both computers, then you can also sync files depend upon the correct location of other files, like shortcuts, playlists and office documents that link to other office documents, and the synchronized files still work on the other computer! Tip #25.  Hide Files You Never Need to See If you have your files well organized, you will often be able to tell if a file is out of place just by glancing at the contents of a folder (for example, it should be pretty obvious if you look in a folder that contains all the MP3s from one music CD and see a Word document in there).  This is a good thing – it allows you to determine if there are files out of place with a quick glance.  Yet sometimes there are files in a folder that seem out of place but actually need to be there, such as the “folder art” JPEGs in music folders, and various files in the root of the C: drive.  If such files never need to be opened by you, then a good idea is to simply hide them.  Then, the next time you glance at the folder, you won’t have to remember whether that file was supposed to be there or not, because you won’t see it at all! To hide a file, simply right-click on it and choose Properties: Then simply tick the Hidden tick-box:   Tip #26.  Keep Every Setup File These days most software is downloaded from the Internet.  Whenever you download a piece of software, keep it.  You’ll never know when you need to reinstall the software. Further, keep with it an Internet shortcut that links back to the website where you originally downloaded it, in case you ever need to check for updates. See tip #33 below for a full description of the excellence of organizing your setup files. Tip #27.  Try to Minimize the Number of Folders that Contain Both Files and Sub-folders Some of the folders in your organizational structure will contain only files.  Others will contain only sub-folders.  And you will also have some folders that contain both files and sub-folders.  You will notice slight improvements in how long it takes you to locate a file if you try to avoid this third type of folder.  It’s not always possible, of course – you’ll always have some of these folders, but see if you can avoid it. One way of doing this is to take all the leftover files that didn’t end up getting stored in a sub-folder and create a special “Miscellaneous” or “Other” folder for them. Tip #28.  Starting a Filename with an Underscore Brings it to the Top of a List Further to the previous tip, if you name that “Miscellaneous” or “Other” folder in such a way that its name begins with an underscore “_”, then it will appear at the top of the list of files/folders. The screenshot below is an example of this.  Each folder in the list contains a set of digital photos.  The folder at the top of the list, _Misc, contains random photos that didn’t deserve their own dedicated folder: Tip #29.  Clean Up those CD-ROMs and (shudder!) Floppy Disks Have you got a pile of CD-ROMs stacked on a shelf of your office?  Old photos, or files you archived off onto CD-ROM (or even worse, floppy disks!) because you didn’t have enough disk space at the time?  In the meantime have you upgraded your computer and now have 500 Gigabytes of space you don’t know what to do with?  If so, isn’t it time you tidied up that stack of disks and filed them into your gorgeous new folder structure? So what are you waiting for?  Bite the bullet, copy them all back onto your computer, file them in their appropriate folders, and then back the whole lot up onto a shiny new 1000Gig external hard drive! Useful Folders to Create This next section suggests some useful folders that you might want to create within your folder structure.  I’ve personally found them to be indispensable. The first three are all about convenience – handy folders to create and then put somewhere that you can always access instantly.  For each one, it’s not so important where the actual folder is located, but it’s very important where you put the shortcut(s) to the folder.  You might want to locate the shortcuts: On your Desktop In your “Quick Launch” area (or pinned to your Windows 7 Superbar) In your Windows Explorer “Favorite Links” area Tip #30.  Create an “Inbox” (“To-Do”) Folder This has already been mentioned in depth (see tip #13), but we wanted to reiterate its importance here.  This folder contains all the recently created, received or downloaded files that you have not yet had a chance to file away properly, and it also may contain files that you have yet to process.  In effect, it becomes a sort of “to-do list”.  It doesn’t have to be called “Inbox” – you can call it whatever you want. Tip #31.  Create a Folder where Your Current Projects are Collected Rather than going hunting for them all the time, or dumping them all on your desktop, create a special folder where you put links (or work folders) for each of the projects you’re currently working on. You can locate this folder in your “Inbox” folder, on your desktop, or anywhere at all – just so long as there’s a way of getting to it quickly, such as putting a link to it in Windows Explorer’s “Favorite Links” area: Tip #32.  Create a Folder for Files and Folders that You Regularly Open You will always have a few files that you open regularly, whether it be a spreadsheet of your current accounts, or a favorite playlist.  These are not necessarily “current projects”, rather they’re simply files that you always find yourself opening.  Typically such files would be located on your desktop (or even better, shortcuts to those files).  Why not collect all such shortcuts together and put them in their own special folder? As with the “Current Projects” folder (above), you would want to locate that folder somewhere convenient.  Below is an example of a folder called “Quick links”, with about seven files (shortcuts) in it, that is accessible through the Windows Quick Launch bar: See tip #37 below for a full explanation of the power of the Quick Launch bar. Tip #33.  Create a “Set-ups” Folder A typical computer has dozens of applications installed on it.  For each piece of software, there are often many different pieces of information you need to keep track of, including: The original installation setup file(s).  This can be anything from a simple 100Kb setup.exe file you downloaded from a website, all the way up to a 4Gig ISO file that you copied from a DVD-ROM that you purchased. The home page of the software manufacturer (in case you need to look up something on their support pages, their forum or their online help) The page containing the download link for your actual file (in case you need to re-download it, or download an upgraded version) The serial number Your proof-of-purchase documentation Any other template files, plug-ins, themes, etc that also need to get installed For each piece of software, it’s a great idea to gather all of these files together and put them in a single folder.  The folder can be the name of the software (plus possibly a very brief description of what it’s for – in case you can’t remember what the software does based in its name).  Then you would gather all of these folders together into one place, and call it something like “Software” or “Setups”. If you have enough of these folders (I have several hundred, being a geek, collected over 20 years), then you may want to further categorize them.  My own categorization structure is based on “platform” (operating system): The last seven folders each represents one platform/operating system, while _Operating Systems contains set-up files for installing the operating systems themselves.  _Hardware contains ROMs for hardware I own, such as routers. Within the Windows folder (above), you can see the beginnings of the vast library of software I’ve compiled over the years: An example of a typical application folder looks like this: Tip #34.  Have a “Settings” Folder We all know that our documents are important.  So are our photos and music files.  We save all of these files into folders, and then locate them afterwards and double-click on them to open them.  But there are many files that are important to us that can’t be saved into folders, and then searched for and double-clicked later on.  These files certainly contain important information that we need, but are often created internally by an application, and saved wherever that application feels is appropriate. A good example of this is the “PST” file that Outlook creates for us and uses to store all our emails, contacts, appointments and so forth.  Another example would be the collection of Bookmarks that Firefox stores on your behalf. And yet another example would be the customized settings and configuration files of our all our software.  Granted, most Windows programs store their configuration in the Registry, but there are still many programs that use configuration files to store their settings. Imagine if you lost all of the above files!  And yet, when people are backing up their computers, they typically only back up the files they know about – those that are stored in the “My Documents” folder, etc.  If they had a hard disk failure or their computer was lost or stolen, their backup files would not include some of the most vital files they owned.  Also, when migrating to a new computer, it’s vital to ensure that these files make the journey. It can be a very useful idea to create yourself a folder to store all your “settings” – files that are important to you but which you never actually search for by name and double-click on to open them.  Otherwise, next time you go to set up a new computer just the way you want it, you’ll need to spend hours recreating the configuration of your previous computer! So how to we get our important files into this folder?  Well, we have a few options: Some programs (such as Outlook and its PST files) allow you to place these files wherever you want.  If you delve into the program’s options, you will find a setting somewhere that controls the location of the important settings files (or “personal storage” – PST – when it comes to Outlook) Some programs do not allow you to change such locations in any easy way, but if you get into the Registry, you can sometimes find a registry key that refers to the location of the file(s).  Simply move the file into your Settings folder and adjust the registry key to refer to the new location. Some programs stubbornly refuse to allow their settings files to be placed anywhere other then where they stipulate.  When faced with programs like these, you have three choices:  (1) You can ignore those files, (2) You can copy the files into your Settings folder (let’s face it – settings don’t change very often), or (3) you can use synchronization software, such as the Windows Briefcase, to make synchronized copies of all your files in your Settings folder.  All you then have to do is to remember to run your sync software periodically (perhaps just before you run your backup software!). There are some other things you may decide to locate inside this new “Settings” folder: Exports of registry keys (from the many applications that store their configurations in the Registry).  This is useful for backup purposes or for migrating to a new computer Notes you’ve made about all the specific customizations you have made to a particular piece of software (so that you’ll know how to do it all again on your next computer) Shortcuts to webpages that detail how to tweak certain aspects of your operating system or applications so they are just the way you like them (such as how to remove the words “Shortcut to” from the beginning of newly created shortcuts).  In other words, you’d want to create shortcuts to half the pages on the How-To Geek website! Here’s an example of a “Settings” folder: Windows Features that Help with Organization This section details some of the features of Microsoft Windows that are a boon to anyone hoping to stay optimally organized. Tip #35.  Use the “Favorite Links” Area to Access Oft-Used Folders Once you’ve created your great new filing system, work out which folders you access most regularly, or which serve as great starting points for locating the rest of the files in your folder structure, and then put links to those folders in your “Favorite Links” area of the left-hand side of the Windows Explorer window (simply called “Favorites” in Windows 7):   Some ideas for folders you might want to add there include: Your “Inbox” folder (or whatever you’ve called it) – most important! The base of your filing structure (e.g. C:\Files) A folder containing shortcuts to often-accessed folders on other computers around the network (shown above as Network Folders) A folder containing shortcuts to your current projects (unless that folder is in your “Inbox” folder) Getting folders into this area is very simple – just locate the folder you’re interested in and drag it there! Tip #36.  Customize the Places Bar in the File/Open and File/Save Boxes Consider the screenshot below: The highlighted icons (collectively known as the “Places Bar”) can be customized to refer to any folder location you want, allowing instant access to any part of your organizational structure. Note:  These File/Open and File/Save boxes have been superseded by new versions that use the Windows Vista/Windows 7 “Favorite Links”, but the older versions (shown above) are still used by a surprisingly large number of applications. The easiest way to customize these icons is to use the Group Policy Editor, but not everyone has access to this program.  If you do, open it up and navigate to: User Configuration > Administrative Templates > Windows Components > Windows Explorer > Common Open File Dialog If you don’t have access to the Group Policy Editor, then you’ll need to get into the Registry.  Navigate to: HKEY_CURRENT_USER \ Software \ Microsoft  \ Windows \ CurrentVersion \ Policies \ comdlg32 \ Placesbar It should then be easy to make the desired changes.  Log off and log on again to allow the changes to take effect. Tip #37.  Use the Quick Launch Bar as a Application and File Launcher That Quick Launch bar (to the right of the Start button) is a lot more useful than people give it credit for.  Most people simply have half a dozen icons in it, and use it to start just those programs.  But it can actually be used to instantly access just about anything in your filing system: For complete instructions on how to set this up, visit our dedicated article on this topic. Tip #38.  Put a Shortcut to Windows Explorer into Your Quick Launch Bar This is only necessary in Windows Vista and Windows XP.  The Microsoft boffins finally got wise and added it to the Windows 7 Superbar by default. Windows Explorer – the program used for managing your files and folders – is one of the most useful programs in Windows.  Anyone who considers themselves serious about being organized needs instant access to this program at any time.  A great place to create a shortcut to this program is in the Windows XP and Windows Vista “Quick Launch” bar: To get it there, locate it in your Start Menu (usually under “Accessories”) and then right-drag it down into your Quick Launch bar (and create a copy). Tip #39.  Customize the Starting Folder for Your Windows 7 Explorer Superbar Icon If you’re on Windows 7, your Superbar will include a Windows Explorer icon.  Clicking on the icon will launch Windows Explorer (of course), and will start you off in your “Libraries” folder.  Libraries may be fine as a starting point, but if you have created yourself an “Inbox” folder, then it would probably make more sense to start off in this folder every time you launch Windows Explorer. To change this default/starting folder location, then first right-click the Explorer icon in the Superbar, and then right-click Properties:Then, in Target field of the Windows Explorer Properties box that appears, type %windir%\explorer.exe followed by the path of the folder you wish to start in.  For example: %windir%\explorer.exe C:\Files If that folder happened to be on the Desktop (and called, say, “Inbox”), then you would use the following cleverness: %windir%\explorer.exe shell:desktop\Inbox Then click OK and test it out. Tip #40.  Ummmmm…. No, that’s it.  I can’t think of another one.  That’s all of the tips I can come up with.  I only created this one because 40 is such a nice round number… Case Study – An Organized PC To finish off the article, I have included a few screenshots of my (main) computer (running Vista).  The aim here is twofold: To give you a sense of what it looks like when the above, sometimes abstract, tips are applied to a real-life computer, and To offer some ideas about folders and structure that you may want to steal to use on your own PC. Let’s start with the C: drive itself.  Very minimal.  All my files are contained within C:\Files.  I’ll confine the rest of the case study to this folder: That folder contains the following: Mark: My personal files VC: My business (Virtual Creations, Australia) Others contains files created by friends and family Data contains files from the rest of the world (can be thought of as “public” files, usually downloaded from the Net) Settings is described above in tip #34 The Data folder contains the following sub-folders: Audio:  Radio plays, audio books, podcasts, etc Development:  Programmer and developer resources, sample source code, etc (see below) Humour:  Jokes, funnies (those emails that we all receive) Movies:  Downloaded and ripped movies (all legal, of course!), their scripts, DVD covers, etc. Music:  (see below) Setups:  Installation files for software (explained in full in tip #33) System:  (see below) TV:  Downloaded TV shows Writings:  Books, instruction manuals, etc (see below) The Music folder contains the following sub-folders: Album covers:  JPEG scans Guitar tabs:  Text files of guitar sheet music Lists:  e.g. “Top 1000 songs of all time” Lyrics:  Text files MIDI:  Electronic music files MP3 (representing 99% of the Music folder):  MP3s, either ripped from CDs or downloaded, sorted by artist/album name Music Video:  Video clips Sheet Music:  usually PDFs The Data\Writings folder contains the following sub-folders: (all pretty self-explanatory) The Data\Development folder contains the following sub-folders: Again, all pretty self-explanatory (if you’re a geek) The Data\System folder contains the following sub-folders: These are usually themes, plug-ins and other downloadable program-specific resources. The Mark folder contains the following sub-folders: From Others:  Usually letters that other people (friends, family, etc) have written to me For Others:  Letters and other things I have created for other people Green Book:  None of your business Playlists:  M3U files that I have compiled of my favorite songs (plus one M3U playlist file for every album I own) Writing:  Fiction, philosophy and other musings of mine Mark Docs:  Shortcut to C:\Users\Mark Settings:  Shortcut to C:\Files\Settings\Mark The Others folder contains the following sub-folders: The VC (Virtual Creations, my business – I develop websites) folder contains the following sub-folders: And again, all of those are pretty self-explanatory. Conclusion These tips have saved my sanity and helped keep me a productive geek, but what about you? What tips and tricks do you have to keep your files organized?  Please share them with us in the comments.  Come on, don’t be shy… Similar Articles Productive Geek Tips Fix For When Windows Explorer in Vista Stops Showing File NamesWhy Did Windows Vista’s Music Folder Icon Turn Yellow?Print or Create a Text File List of the Contents in a Directory the Easy WayCustomize the Windows 7 or Vista Send To MenuAdd Copy To / Move To on Windows 7 or Vista Right-Click Menu TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows Track Daily Goals With 42Goals Video Toolbox is a Superb Online Video Editor Fun with 47 charts and graphs Tomorrow is Mother’s Day Check the Average Speed of YouTube Videos You’ve Watched OutlookStatView Scans and Displays General Usage Statistics

    Read the article

  • Ajax Control Toolkit July 2011 Release and the New HTML Editor Extender

    - by Stephen Walther
    I’m happy to announce the July 2011 release of the Ajax Control Toolkit which includes important bug fixes and a completely new HTML Editor Extender control. You can download the July 2011 Release by visiting the Ajax Control Toolkit CodePlex site at: http://AjaxControlToolkit.CodePlex.com Using the New HTML Editor Extender Control You can use the new HTML Editor Extender to extend any standard ASP.NET TextBox control so that it supports rich formatting such as bold, italics, bulleted lists, numbered lists, typefaces and different foreground and background colors. The following code illustrates how you can extend a standard ASP.NET TextBox control with the HtmlEditorExtender: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Simple.aspx.cs" Inherits="WebApplication1.Simple" %> <%@ Register TagPrefix="asp" Namespace="AjaxControlToolkit" Assembly="AjaxControlToolkit" %> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title>Simple</title> </head> <body> <form id="form1" runat="server"> <asp:ToolkitScriptManager runat="Server" /> <asp:TextBox ID="txtComments" TextMode="MultiLine" Columns="60" Rows="8" runat="server" /> <asp:HtmlEditorExtender TargetControlID="txtComments" runat="server" /> </form> </body> </html> This page has the following three controls: ToolkitScriptManager – The ToolkitScriptManager renders all of the scripts required by the Ajax Control Toolkit. TextBox – The TextBox control is a standard ASP.NET TextBox which is set to display multiple lines (a TextArea instead of an Input element). HtmlEditorExtender – The HtmlEditorExtender is set to extend the TextBox control. You can use the standard TextBox Text property to read the rich text entered into the TextBox control on the server. Lightweight and HTML5 The HTML Editor Extender works on all modern browsers including the most recent versions of Mozilla Firefox (Firefox 5), Google Chrome (Chrome 12), and Apple Safari (Safari 5). Furthermore, the HTML Editor Extender is compatible with Microsoft Internet Explorer 6 and newer. The HTML Editor Extender is very lightweight. It takes advantage of the HTML5 ContentEditable attribute so it does not require an iframe or complex browser workarounds. If you select View Source in your browser while using the HTML Editor Extender, we hope that you will be pleasantly surprised by how little markup and script is generated by the HTML Editor Extender. Customizable Toolbar Buttons Depending on the web application that you are building, you will want to display different toolbar buttons with the HTML Editor Extender. One of the design goals of the HTML Editor Extender was to make it very easy for you to customize the toolbar buttons. Imagine, for example, that you want to use the HTML Editor Extender when accepting comments on blog posts. In that case, you might want to restrict the type of formatting that a user can display. You might want to enable a user to format text as bold or italic but you do not want the user to make any other formatting changes. The following page illustrates how you can customize the HTML Editor Extender toolbar: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="CustomToolbar.aspx.cs" Inherits="WebApplication1.CustomToolbar" %> <%@ Register TagPrefix="asp" Namespace="AjaxControlToolkit" Assembly="AjaxControlToolkit" %> <html> <head runat="server"> <title>Custom Toolbar</title> </head> <body> <form id="form1" runat="server"> <asp:ToolkitScriptManager Runat="server" /> <asp:TextBox ID="txtComments" TextMode="MultiLine" Columns="50" Rows="10" Text="Hello <b>world!</b>" Runat="server" /> <asp:HtmlEditorExtender TargetControlID="txtComments" runat="server"> <Toolbar> <asp:Bold /> <asp:Italic /> </Toolbar> </asp:HtmlEditorExtender> </form> </body> </html> Notice that the HTML Editor Extender in the page above has a Toolbar subtag. You can list the toolbar buttons which you want to appear within the subtag. In the case above, only Bold and Italic buttons are displayed. Here is a complete list of the Toolbar buttons currently supported by the HTML Editor Extender: Undo Redo Bold Italic Underline StrikeThrough Subscript Superscript JustifyLeft JustifyCenter JustifyRight JustifyFull InsertOrderedList InsertUnorderedList CreateLink UnLink RemoveFormat SelectAll UnSelect Delete Cut Copy Paste BackgroundColorSelector ForeColorSelector FontNameSelector FontSizeSelector Indent Outdent InsertHorizontalRule HorizontalSeparator Of course the HTML Editor Extender was designed to be extensible. You can create your own buttons and add them to the control. Compatible with the AntiXSS Library When using the HTML Editor Extender on a public facing website, we strongly recommend that you use the HTML Editor Extender with the AntiXSS Library. If you allow users to submit arbitrary HTML, and you don’t take any action to strip out malicious markup, then you are opening your website to Cross-Site Scripting Attacks (XSS attacks). The HTML Editor Extender uses the Provider Model to support different Sanitizer Providers. The July 2011 release of the Ajax Control Toolkit ships with a single Sanitizer Provider which uses the AntiXSS library (see http://AntiXss.CodePlex.com ). A Sanitizer Provider is responsible for sanitizing HTML markup by removing any malicious elements, attributes, and attribute values. For example, the AntiXss Sanitizer Provider will take the following block of HTML: <b><a href=""javascript:doEvil()"">Visit Grandma</a></b> <script>doEvil()</script> And return the following sanitized block of HTML: <b><a href="">Visit Grandma</a></b> Notice that the JavaScript href and <SCRIPT> tag are both stripped out. Be aware that there are a depressingly large number of ways to sneak evil markup into your HTML. You definitely want a Sanitizer as a safety net. Before you can use the AntiXSS Sanitizer Provider, you must add three assemblies to your web application: AntiXSSLibrary.dll, HtmlSanitizationLibrary.dll, and SanitizerProviders.dll. All three assemblies are included with the CodePlex download of the Ajax Control Toolkit in the SanitizerProviders folder. Here’s how you modify your web.config file to use the AntiXSS Sanitizer Provider: <configuration> <configSections> <sectionGroup name="system.web"> <section name="sanitizer" requirePermission="false" type="AjaxControlToolkit.Sanitizer.ProviderSanitizerSection, AjaxControlToolkit"/> </sectionGroup> </configSections> <system.web> <compilation targetFramework="4.0" debug="true"/> <sanitizer defaultProvider="AntiXssSanitizerProvider"> <providers> <add name="AntiXssSanitizerProvider" type="AjaxControlToolkit.Sanitizer.AntiXssSanitizerProvider"></add> </providers> </sanitizer> </system.web> </configuration> You can detect whether the HTML Editor Extender is using the AntiXSS Sanitizer Provider by checking the HtmlEditorExtender SanitizerProvider property like this: if (MyHtmlEditorExtender.SanitizerProvider == null) { throw new Exception("Please enable the AntiXss Sanitizer!"); } When the SanitizerProvider property has the value null, you know that a Sanitizer Provider has not been configured in the web.config file. Because the AntiXSS library requires Full Trust, you cannot use the AntiXSS Sanitizer Provider with most shared website hosting providers. Because most shared hosting providers only support Medium Trust and not Full Trust, we do not recommend using the HTML Editor Extender with a public website hosted with a shared hosting provider. Why a New HTML Editor Control? The Ajax Control Toolkit now includes two HTML Editor controls. Why did we introduce a new HTML Editor control when there was already an existing HTML Editor? We think you will like the new HTML Editor much more than the previous one. We had several goals with the new HTML Editor Extender: Lightweight – We wanted to leverage HTML5 to create a lightweight HTML Editor. The new HTML Editor generates much less markup and script than the previous HTML Editor. Secure – We wanted to make it easy to integrate the AntiXSS library with the HTML Editor. If you are creating a public facing website, we strongly recommend that you use the AntiXSS Provider. Customizable – We wanted to make it easy for users to customize the toolbar buttons displayed by the HTML Editor. Compatibility – We wanted to ensure that the HTML Editor will work with the latest versions of the most popular browsers (including Internet Explorer 6 and higher). The old HTML Editor control is still included in the Ajax Control Toolkit and continues to live in the AjaxControlToolkit.HTMLEditor namespace. We have not modified the control and you can continue to use the control in the same way as you have used it in the past. However, we hope that you will consider migrating to the new HTML Editor Extender for the reasons listed above. Summary We’ve introduced a new Ajax Control Toolkit control with this release. I want to thank the developers and testers on the Superexpert team for the huge amount of work which they put into this control. It was a non-trivial task to build an entirely new control which has the complexity of the HTML Editor in less than 6 weeks. Please let us know what you think! We want to hear your feedback. If you discover issues with the new HTML Editor Extender control, or you have questions about the control, or you have ideas for how it can be improved, then please post them to this blog. Tomorrow starts a new sprint

    Read the article

  • SQL SERVER – Guest Posts – Feodor Georgiev – The Context of Our Database Environment – Going Beyond the Internal SQL Server Waits – Wait Type – Day 21 of 28

    - by pinaldave
    This guest post is submitted by Feodor. 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. In this article Feodor explains the server-client-server process, and concentrated on the mutual waits between client and SQL Server. This is essential in grasping the concept of waits in a ‘global’ application plan. Recently I was asked to write a blog post about the wait statistics in SQL Server and since I had been thinking about writing it for quite some time now, here it is. It is a wide-spread idea that the wait statistics in SQL Server will tell you everything about your performance. Well, almost. Or should I say – barely. The reason for this is that SQL Server is always a part of a bigger system – there are always other players in the game: whether it is a client application, web service, any other kind of data import/export process and so on. In short, the SQL Server surroundings look like this: This means that SQL Server, aside from its internal waits, also depends on external waits and settings. As we can see in the picture above, SQL Server needs to have an interface in order to communicate with the surrounding clients over the network. For this communication, SQL Server uses protocol interfaces. I will not go into detail about which protocols are best, but you can read this article. Also, review the information about the TDS (Tabular data stream). As we all know, our system is only as fast as its slowest component. This means that when we look at our environment as a whole, the SQL Server might be a victim of external pressure, no matter how well we have tuned our database server performance. Let’s dive into an example: let’s say that we have a web server, hosting a web application which is using data from our SQL Server, hosted on another server. The network card of the web server for some reason is malfunctioning (think of a hardware failure, driver failure, or just improper setup) and does not send/receive data faster than 10Mbs. On the other end, our SQL Server will not be able to send/receive data at a faster rate either. This means that the application users will notify the support team and will say: “My data is coming very slow.” Now, let’s move on to a bit more exciting example: imagine that there is a similar setup as the example above – one web server and one database server, and the application is not using any stored procedure calls, but instead for every user request the application is sending 80kb query over the network to the SQL Server. (I really thought this does not happen in real life until I saw it one day.) So, what happens in this case? To make things worse, let’s say that the 80kb query text is submitted from the application to the SQL Server at least 100 times per minute, and as often as 300 times per minute in peak times. Here is what happens: in order for this query to reach the SQL Server, it will have to be broken into a of number network packets (according to the packet size settings) – and will travel over the network. On the other side, our SQL Server network card will receive the packets, will pass them to our network layer, the packets will get assembled, and eventually SQL Server will start processing the query – parsing, allegorizing, generating the query execution plan and so on. So far, we have already had a serious network overhead by waiting for the packets to reach our Database Engine. There will certainly be some processing overhead – until the database engine deals with the 80kb query and its 20 subqueries. The waits you see in the DMVs are actually collected from the point the query reaches the SQL Server and the packets are assembled. Let’s say that our query is processed and it finally returns 15000 rows. These rows have a certain size as well, depending on the data types returned. This means that the data will have converted to packages (depending on the network size package settings) and will have to reach the application server. There will also be waits, however, this time you will be able to see a wait type in the DMVs called ASYNC_NETWORK_IO. What this wait type indicates is that the client is not consuming the data fast enough and the network buffers are filling up. Recently Pinal Dave posted a blog on Client Statistics. What Client Statistics does is captures the physical flow characteristics of the query between the client(Management Studio, in this case) and the server and back to the client. As you see in the image, there are three categories: Query Profile Statistics, Network Statistics and Time Statistics. Number of server roundtrips–a roundtrip consists of a request sent to the server and a reply from the server to the client. For example, if your query has three select statements, and they are separated by ‘GO’ command, then there will be three different roundtrips. TDS Packets sent from the client – TDS (tabular data stream) is the language which SQL Server speaks, and in order for applications to communicate with SQL Server, they need to pack the requests in TDS packets. TDS Packets sent from the client is the number of packets sent from the client; in case the request is large, then it may need more buffers, and eventually might even need more server roundtrips. TDS packets received from server –is the TDS packets sent by the server to the client during the query execution. Bytes sent from client – is the volume of the data set to our SQL Server, measured in bytes; i.e. how big of a query we have sent to the SQL Server. This is why it is best to use stored procedures, since the reusable code (which already exists as an object in the SQL Server) will only be called as a name of procedure + parameters, and this will minimize the network pressure. Bytes received from server – is the amount of data the SQL Server has sent to the client, measured in bytes. Depending on the number of rows and the datatypes involved, this number will vary. But still, think about the network load when you request data from SQL Server. Client processing time – is the amount of time spent in milliseconds between the first received response packet and the last received response packet by the client. Wait time on server replies – is the time in milliseconds between the last request packet which left the client and the first response packet which came back from the server to the client. Total execution time – is the sum of client processing time and wait time on server replies (the SQL Server internal processing time) Here is an illustration of the Client-server communication model which should help you understand the mutual waits in a client-server environment. Keep in mind that a query with a large ‘wait time on server replies’ means the server took a long time to produce the very first row. This is usual on queries that have operators that need the entire sub-query to evaluate before they proceed (for example, sort and top operators). However, a query with a very short ‘wait time on server replies’ means that the query was able to return the first row fast. However a long ‘client processing time’ does not necessarily imply the client spent a lot of time processing and the server was blocked waiting on the client. It can simply mean that the server continued to return rows from the result and this is how long it took until the very last row was returned. The bottom line is that developers and DBAs should work together and think carefully of the resource utilization in the client-server environment. From experience I can say that so far I have seen only cases when the application developers and the Database developers are on their own and do not ask questions about the other party’s world. I would recommend using the Client Statistics tool during new development to track the performance of the queries, and also to find a synchronous way of utilizing resources between the client – server – client. Here is another example: think about similar setup as above, but add another server to the game. Let’s say that we keep our media on a separate server, and together with the data from our SQL Server we need to display some images on the webpage requested by our user. No matter how simple or complicated the logic to get the images is, if the images are 500kb each our users will get the page slowly and they will still think that there is something wrong with our data. Anyway, I don’t mean to get carried away too far from SQL Server. Instead, what I would like to say is that DBAs should also be aware of ‘the big picture’. I wrote a blog post a while back on this topic, and if you are interested, you can read it here about the big picture. And finally, here are some guidelines for monitoring the network performance and improving it: Run a trace and outline all queries that return more than 1000 rows (in Profiler you can actually filter and sort the captured trace by number of returned rows). This is not a set number; it is more of a guideline. The general thought is that no application user can consume that many rows at once. Ask yourself and your fellow-developers: ‘why?’. Monitor your network counters in Perfmon: Network Interface:Output queue length, Redirector:Network errors/sec, TCPv4: Segments retransmitted/sec and so on. Make sure to establish a good friendship with your network administrator (buy them coffee, for example J ) and get into a conversation about the network settings. Have them explain to you how the network cards are setup – are they standalone, are they ‘teamed’, what are the settings – full duplex and so on. Find some time to read a bit about networking. In this short blog post I hope I have turned your attention to ‘the big picture’ and the fact that there are other factors affecting our SQL Server, aside from its internal workings. As a further reading I would still highly recommend the Wait Stats series on this blog, also I would recommend you have the coffee break conversation with your network admin as soon as possible. This guest post is written by Feodor Georgiev. Read all the post in the Wait Types and Queue series. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL

    Read the article

  • Heaps of Trouble?

    - by Paul White NZ
    If you’re not already a regular reader of Brad Schulz’s blog, you’re missing out on some great material.  In his latest entry, he is tasked with optimizing a query run against tables that have no indexes at all.  The problem is, predictably, that performance is not very good.  The catch is that we are not allowed to create any indexes (or even new statistics) as part of our optimization efforts. In this post, I’m going to look at the problem from a slightly different angle, and present an alternative solution to the one Brad found.  Inevitably, there’s going to be some overlap between our entries, and while you don’t necessarily need to read Brad’s post before this one, I do strongly recommend that you read it at some stage; he covers some important points that I won’t cover again here. The Example We’ll use data from the AdventureWorks database, copied to temporary unindexed tables.  A script to create these structures is shown below: CREATE TABLE #Custs ( CustomerID INTEGER NOT NULL, TerritoryID INTEGER NULL, CustomerType NCHAR(1) COLLATE SQL_Latin1_General_CP1_CI_AI NOT NULL, ); GO CREATE TABLE #Prods ( ProductMainID INTEGER NOT NULL, ProductSubID INTEGER NOT NULL, ProductSubSubID INTEGER NOT NULL, Name NVARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AI NOT NULL, ); GO CREATE TABLE #OrdHeader ( SalesOrderID INTEGER NOT NULL, OrderDate DATETIME NOT NULL, SalesOrderNumber NVARCHAR(25) COLLATE SQL_Latin1_General_CP1_CI_AI NOT NULL, CustomerID INTEGER NOT NULL, ); GO CREATE TABLE #OrdDetail ( SalesOrderID INTEGER NOT NULL, OrderQty SMALLINT NOT NULL, LineTotal NUMERIC(38,6) NOT NULL, ProductMainID INTEGER NOT NULL, ProductSubID INTEGER NOT NULL, ProductSubSubID INTEGER NOT NULL, ); GO INSERT #Custs ( CustomerID, TerritoryID, CustomerType ) SELECT C.CustomerID, C.TerritoryID, C.CustomerType FROM AdventureWorks.Sales.Customer C WITH (TABLOCK); GO INSERT #Prods ( ProductMainID, ProductSubID, ProductSubSubID, Name ) SELECT P.ProductID, P.ProductID, P.ProductID, P.Name FROM AdventureWorks.Production.Product P WITH (TABLOCK); GO INSERT #OrdHeader ( SalesOrderID, OrderDate, SalesOrderNumber, CustomerID ) SELECT H.SalesOrderID, H.OrderDate, H.SalesOrderNumber, H.CustomerID FROM AdventureWorks.Sales.SalesOrderHeader H WITH (TABLOCK); GO INSERT #OrdDetail ( SalesOrderID, OrderQty, LineTotal, ProductMainID, ProductSubID, ProductSubSubID ) SELECT D.SalesOrderID, D.OrderQty, D.LineTotal, D.ProductID, D.ProductID, D.ProductID FROM AdventureWorks.Sales.SalesOrderDetail D WITH (TABLOCK); The query itself is a simple join of the four tables: SELECT P.ProductMainID AS PID, P.Name, D.OrderQty, H.SalesOrderNumber, H.OrderDate, C.TerritoryID FROM #Prods P JOIN #OrdDetail D ON P.ProductMainID = D.ProductMainID AND P.ProductSubID = D.ProductSubID AND P.ProductSubSubID = D.ProductSubSubID JOIN #OrdHeader H ON D.SalesOrderID = H.SalesOrderID JOIN #Custs C ON H.CustomerID = C.CustomerID ORDER BY P.ProductMainID ASC OPTION (RECOMPILE, MAXDOP 1); Remember that these tables have no indexes at all, and only the single-column sampled statistics SQL Server automatically creates (assuming default settings).  The estimated query plan produced for the test query looks like this (click to enlarge): The Problem The problem here is one of cardinality estimation – the number of rows SQL Server expects to find at each step of the plan.  The lack of indexes and useful statistical information means that SQL Server does not have the information it needs to make a good estimate.  Every join in the plan shown above estimates that it will produce just a single row as output.  Brad covers the factors that lead to the low estimates in his post. In reality, the join between the #Prods and #OrdDetail tables will produce 121,317 rows.  It should not surprise you that this has rather dire consequences for the remainder of the query plan.  In particular, it makes a nonsense of the optimizer’s decision to use Nested Loops to join to the two remaining tables.  Instead of scanning the #OrdHeader and #Custs tables once (as it expected), it has to perform 121,317 full scans of each.  The query takes somewhere in the region of twenty minutes to run to completion on my development machine. A Solution At this point, you may be thinking the same thing I was: if we really are stuck with no indexes, the best we can do is to use hash joins everywhere. We can force the exclusive use of hash joins in several ways, the two most common being join and query hints.  A join hint means writing the query using the INNER HASH JOIN syntax; using a query hint involves adding OPTION (HASH JOIN) at the bottom of the query.  The difference is that using join hints also forces the order of the join, whereas the query hint gives the optimizer freedom to reorder the joins at its discretion. Adding the OPTION (HASH JOIN) hint results in this estimated plan: That produces the correct output in around seven seconds, which is quite an improvement!  As a purely practical matter, and given the rigid rules of the environment we find ourselves in, we might leave things there.  (We can improve the hashing solution a bit – I’ll come back to that later on). Faster Nested Loops It might surprise you to hear that we can beat the performance of the hash join solution shown above using nested loops joins exclusively, and without breaking the rules we have been set. The key to this part is to realize that a condition like (A = B) can be expressed as (A <= B) AND (A >= B).  Armed with this tremendous new insight, we can rewrite the join predicates like so: SELECT P.ProductMainID AS PID, P.Name, D.OrderQty, H.SalesOrderNumber, H.OrderDate, C.TerritoryID FROM #OrdDetail D JOIN #OrdHeader H ON D.SalesOrderID >= H.SalesOrderID AND D.SalesOrderID <= H.SalesOrderID JOIN #Custs C ON H.CustomerID >= C.CustomerID AND H.CustomerID <= C.CustomerID JOIN #Prods P ON P.ProductMainID >= D.ProductMainID AND P.ProductMainID <= D.ProductMainID AND P.ProductSubID = D.ProductSubID AND P.ProductSubSubID = D.ProductSubSubID ORDER BY D.ProductMainID OPTION (RECOMPILE, LOOP JOIN, MAXDOP 1, FORCE ORDER); I’ve also added LOOP JOIN and FORCE ORDER query hints to ensure that only nested loops joins are used, and that the tables are joined in the order they appear.  The new estimated execution plan is: This new query runs in under 2 seconds. Why Is It Faster? The main reason for the improvement is the appearance of the eager Index Spools, which are also known as index-on-the-fly spools.  If you read my Inside The Optimiser series you might be interested to know that the rule responsible is called JoinToIndexOnTheFly. An eager index spool consumes all rows from the table it sits above, and builds a index suitable for the join to seek on.  Taking the index spool above the #Custs table as an example, it reads all the CustomerID and TerritoryID values with a single scan of the table, and builds an index keyed on CustomerID.  The term ‘eager’ means that the spool consumes all of its input rows when it starts up.  The index is built in a work table in tempdb, has no associated statistics, and only exists until the query finishes executing. The result is that each unindexed table is only scanned once, and just for the columns necessary to build the temporary index.  From that point on, every execution of the inner side of the join is answered by a seek on the temporary index – not the base table. A second optimization is that the sort on ProductMainID (required by the ORDER BY clause) is performed early, on just the rows coming from the #OrdDetail table.  The optimizer has a good estimate for the number of rows it needs to sort at that stage – it is just the cardinality of the table itself.  The accuracy of the estimate there is important because it helps determine the memory grant given to the sort operation.  Nested loops join preserves the order of rows on its outer input, so sorting early is safe.  (Hash joins do not preserve order in this way, of course). The extra lazy spool on the #Prods branch is a further optimization that avoids executing the seek on the temporary index if the value being joined (the ‘outer reference’) hasn’t changed from the last row received on the outer input.  It takes advantage of the fact that rows are still sorted on ProductMainID, so if duplicates exist, they will arrive at the join operator one after the other. The optimizer is quite conservative about introducing index spools into a plan, because creating and dropping a temporary index is a relatively expensive operation.  It’s presence in a plan is often an indication that a useful index is missing. I want to stress that I rewrote the query in this way primarily as an educational exercise – I can’t imagine having to do something so horrible to a production system. Improving the Hash Join I promised I would return to the solution that uses hash joins.  You might be puzzled that SQL Server can create three new indexes (and perform all those nested loops iterations) faster than it can perform three hash joins.  The answer, again, is down to the poor information available to the optimizer.  Let’s look at the hash join plan again: Two of the hash joins have single-row estimates on their build inputs.  SQL Server fixes the amount of memory available for the hash table based on this cardinality estimate, so at run time the hash join very quickly runs out of memory. This results in the join spilling hash buckets to disk, and any rows from the probe input that hash to the spilled buckets also get written to disk.  The join process then continues, and may again run out of memory.  This is a recursive process, which may eventually result in SQL Server resorting to a bailout join algorithm, which is guaranteed to complete eventually, but may be very slow.  The data sizes in the example tables are not large enough to force a hash bailout, but it does result in multiple levels of hash recursion.  You can see this for yourself by tracing the Hash Warning event using the Profiler tool. The final sort in the plan also suffers from a similar problem: it receives very little memory and has to perform multiple sort passes, saving intermediate runs to disk (the Sort Warnings Profiler event can be used to confirm this).  Notice also that because hash joins don’t preserve sort order, the sort cannot be pushed down the plan toward the #OrdDetail table, as in the nested loops plan. Ok, so now we understand the problems, what can we do to fix it?  We can address the hash spilling by forcing a different order for the joins: SELECT P.ProductMainID AS PID, P.Name, D.OrderQty, H.SalesOrderNumber, H.OrderDate, C.TerritoryID FROM #Prods P JOIN #Custs C JOIN #OrdHeader H ON H.CustomerID = C.CustomerID JOIN #OrdDetail D ON D.SalesOrderID = H.SalesOrderID ON P.ProductMainID = D.ProductMainID AND P.ProductSubID = D.ProductSubID AND P.ProductSubSubID = D.ProductSubSubID ORDER BY D.ProductMainID OPTION (MAXDOP 1, HASH JOIN, FORCE ORDER); With this plan, each of the inputs to the hash joins has a good estimate, and no hash recursion occurs.  The final sort still suffers from the one-row estimate problem, and we get a single-pass sort warning as it writes rows to disk.  Even so, the query runs to completion in three or four seconds.  That’s around half the time of the previous hashing solution, but still not as fast as the nested loops trickery. Final Thoughts SQL Server’s optimizer makes cost-based decisions, so it is vital to provide it with accurate information.  We can’t really blame the performance problems highlighted here on anything other than the decision to use completely unindexed tables, and not to allow the creation of additional statistics. I should probably stress that the nested loops solution shown above is not one I would normally contemplate in the real world.  It’s there primarily for its educational and entertainment value.  I might perhaps use it to demonstrate to the sceptical that SQL Server itself is crying out for an index. Be sure to read Brad’s original post for more details.  My grateful thanks to him for granting permission to reuse some of his material. Paul White Email: [email protected] Twitter: @PaulWhiteNZ

    Read the article

  • Building a Windows Phone 7 Twitter Application using Silverlight

    - by ScottGu
    On Monday I had the opportunity to present the MIX 2010 Day 1 Keynote in Las Vegas (you can watch a video of it here).  In the keynote I announced the release of the Silverlight 4 Release Candidate (we’ll ship the final release of it next month) and the VS 2010 RC tools for Silverlight 4.  I also had the chance to talk for the first time about how Silverlight and XNA can now be used to build Windows Phone 7 applications. During my talk I did two quick Windows Phone 7 coding demos using Silverlight – a quick “Hello World” application and a “Twitter” data-snacking application.  Both applications were easy to build and only took a few minutes to create on stage.  Below are the steps you can follow yourself to build them on your own machines as well. [Note: In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Building a “Hello World” Windows Phone 7 Application First make sure you’ve installed the Windows Phone Developer Tools CTP – this includes the Visual Studio 2010 Express for Windows Phone development tool (which will be free forever and is the only thing you need to develop and build Windows Phone 7 applications) as well as an add-on to the VS 2010 RC that enables phone development within the full VS 2010 as well. After you’ve downloaded and installed the Windows Phone Developer Tools CTP, launch the Visual Studio 2010 Express for Windows Phone that it installs or launch the VS 2010 RC (if you have it already installed), and then choose “File”->”New Project.”  Here, you’ll find the usual list of project template types along with a new category: “Silverlight for Windows Phone”. The first CTP offers two application project templates. The first is the “Windows Phone Application” template - this is what we’ll use for this example. The second is the “Windows Phone List Application” template - which provides the basic layout for a master-details phone application: After creating a new project, you’ll get a view of the design surface and markup. Notice that the design surface shows the phone UI, letting you easily see how your application will look while you develop. For those familiar with Visual Studio, you’ll also find the familiar ToolBox, Solution Explorer and Properties pane. For our HelloWorld application, we’ll start out by adding a TextBox and a Button from the Toolbox. Notice that you get the same design experience as you do for Silverlight on the web or desktop. You can easily resize, position and align your controls on the design surface. Changing properties is easy with the Properties pane. We’ll change the name of the TextBox that we added to username and change the page title text to “Hello world.” We’ll then write some code by double-clicking on the button and create an event handler in the code-behind file (MainPage.xaml.cs). We’ll start out by changing the title text of the application. The project template included this title as a TextBlock with the name textBlockListTitle (note that the current name incorrectly includes the word “list”; that will be fixed for the final release.)  As we write code against it we get intellisense showing the members available.  Below we’ll set the Text property of the title TextBlock to “Hello “ + the Text property of the TextBox username: We now have all the code necessary for a Hello World application.  We have two choices when it comes to deploying and running the application. We can either deploy to an actual device itself or use the built-in phone emulator: Because the phone emulator is actually the phone operating system running in a virtual machine, we’ll get the same experience developing in the emulator as on the device. For this sample, we’ll just press F5 to start the application with debugging using the emulator.  Once the phone operating system loads, the emulator will run the new “Hello world” application exactly as it would on the device: Notice that we can change several settings of the emulator experience with the emulator toolbar – which is a floating toolbar on the top right.  This includes the ability to re-size/zoom the emulator and two rotate buttons.  Zoom lets us zoom into even the smallest detail of the application: The orientation buttons allow us easily see what the application looks like in landscape mode (orientation change support is just built into the default template): Note that the emulator can be reused across F5 debug sessions - that means that we don’t have to start the emulator for every deployment. We’ve added a dialog that will help you from accidentally shutting down the emulator if you want to reuse it.  Launching an application on an already running emulator should only take ~3 seconds to deploy and run. Within our Hello World application we’ll click the “username” textbox to give it focus.  This will cause the software input panel (SIP) to open up automatically.  We can either type a message or – since we are using the emulator – just type in text.  Note that the emulator works with Windows 7 multi-touch so, if you have a touchscreen, you can see how interaction will feel on a device just by pressing the screen. We’ll enter “MIX 10” in the textbox and then click the button – this will cause the title to update to be “Hello MIX 10”: We provide the same Visual Studio experience when developing for the phone as other .NET applications. This means that we can set a breakpoint within the button event handler, press the button again and have it break within the debugger: Building a “Twitter” Windows Phone 7 Application using Silverlight Rather than just stop with “Hello World” let’s keep going and evolve it to be a basic Twitter client application. We’ll return to the design surface and add a ListBox, using the snaplines within the designer to fit it to the device screen and make the best use of phone screen real estate.  We’ll also rename the Button “Lookup”: We’ll then return to the Button event handler in Main.xaml.cs, and remove the original “Hello World” line of code and take advantage of the WebClient networking class to asynchronously download a Twitter feed. This takes three lines of code in total: (1) declaring and creating the WebClient, (2) attaching an event handler and then (3) calling the asynchronous DownloadStringAsync method. In the DownloadStringAsync call, we’ll pass a Twitter Uri plus a query string which pulls the text from the “username” TextBox. This feed will pull down the respective user’s most frequent posts in an XML format. When the call completes, the DownloadStringCompleted event is fired and our generated event handler twitter_DownloadStringCompleted will be called: The result returned from the Twitter call will come back in an XML based format.  To parse this we’ll use LINQ to XML. LINQ to XML lets us create simple queries for accessing data in an xml feed. To use this library, we’ll first need to add a reference to the assembly (right click on the References folder in the solution explorer and choose “Add Reference): We’ll then add a “using System.Xml.Linq” namespace reference at the top of the code-behind file at the top of Main.xaml.cs file: We’ll then add a simple helper class called TwitterItem to our project. TwitterItem has three string members – UserName, Message and ImageSource: We’ll then implement the twitter_DownloadStringCompleted event handler and use LINQ to XML to parse the returned XML string from Twitter.  What the query is doing is pulling out the three key pieces of information for each Twitter post from the username we passed as the query string. These are the ImageSource for their profile image, the Message of their tweet and their UserName. For each Tweet in the XML, we are creating a new TwitterItem in the IEnumerable<XElement> returned by the Linq query.  We then assign the generated TwitterItem sequence to the ListBox’s ItemsSource property: We’ll then do one more step to complete the application. In the Main.xaml file, we’ll add an ItemTemplate to the ListBox. For the demo, I used a simple template that uses databinding to show the user’s profile image, their tweet and their username. <ListBox Height="521" HorizonalAlignment="Left" Margin="0,131,0,0" Name="listBox1" VerticalAlignment="Top" Width="476"> <ListBox.ItemTemplate> <DataTemplate> <StackPanel Orientation="Horizontal" Height="132"> <Image Source="{Binding ImageSource}" Height="73" Width="73" VerticalAlignment="Top" Margin="0,10,8,0"/> <StackPanel Width="370"> <TextBlock Text="{Binding UserName}" Foreground="#FFC8AB14" FontSize="28" /> <TextBlock Text="{Binding Message}" TextWrapping="Wrap" FontSize="24" /> </StackPanel> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> </ListBox> Now, pressing F5 again, we are able to reuse the emulator and re-run the application. Once the application has launched, we can type in a Twitter username and press the  Button to see the results. Try my Twitter user name (scottgu) and you’ll get back a result of TwitterItems in the Listbox: Try using the mouse (or if you have a touchscreen device your finger) to scroll the items in the Listbox – you should find that they move very fast within the emulator.  This is because the emulator is hardware accelerated – and so gives you the same fast performance that you get on the actual phone hardware. Summary Silverlight and the VS 2010 Tools for Windows Phone (and the corresponding Expression Blend Tools for Windows Phone) make building Windows Phone applications both really easy and fun.  At MIX this week a number of great partners (including Netflix, FourSquare, Seesmic, Shazaam, Major League Soccer, Graphic.ly, Associated Press, Jackson Fish and more) showed off some killer application prototypes they’ve built over the last few weeks.  You can watch my full day 1 keynote to see them in action. I think they start to show some of the promise and potential of using Silverlight with Windows Phone 7.  I’ll be doing more blog posts in the weeks and months ahead that cover that more. Hope this helps, Scott

    Read the article

  • C# coding standards” Use the const directive only on natural constants

    - by Nathan Wilfert
    I've seen these 2 guidelines in coding c# standard and I’m not sure the what the 2nd one means. With the exception of zero and one, never hard-code a numeric value; always declare a constant instead. Use the const directive only on natural constants such as the number of days of the week. 1st what is the definition of a natural constants and if the number is not a natural constants given the 1st rule how does one declare a constant in c# without the const directive? See http://www.scribd.com/doc/10731655/IDesign-C-Coding-Standard-232 for reference.

    Read the article

  • SmoothLife Is a Super Smooth Version of Conway’s Game of Life [Video]

    - by Jason Fitzpatrick
    What happens if you change cellular automaton program Game of Life to use floating point values instead of integers? You end up with SmoothLife, a fluid and organic growth simulator. SmoothLife is a family of rules created by Stephan Rafler. It was designed as a continuous version of Conway’s Game of Life – using floating point values instead of integers. This rule is SmoothLifeL which supports many interesting phenomena such as gliders that can travel in any direction, rotating pairs of gliders, wickstretchers and the appearance of elastic tension in the ‘cords’ that join the blobs. You can check out the paper outlining how SmoothLife works here and then grab the source code to run your own simulation here. [via Boing Boing] HTG Explains: What is the Windows Page File and Should You Disable It? How To Get a Better Wireless Signal and Reduce Wireless Network Interference How To Troubleshoot Internet Connection Problems

    Read the article

  • LLBLGen Pro v3.5 has been released!

    - by FransBouma
    Last weekend we released LLBLGen Pro v3.5! Below the list of what's new in this release. Of course, not everything is on this list, like the large amount of work we put in refactoring the runtime framework. The refactoring was necessary because our framework has two paradigms which are added to the framework at a different time, and from a design perspective in the wrong order (the paradigm we added first, SelfServicing, should have been built on top of Adapter, the other paradigm, which was added more than a year after the first released version). The refactoring made sure the framework re-uses more code across the two paradigms (they already shared a lot of code) and is better prepared for the future. We're not done yet, but refactoring a massive framework like ours without breaking interfaces and existing applications is ... a bit of a challenge ;) To celebrate the release of v3.5, we give every customer a 30% discount! Use the coupon code NR1ORM with your order :) The full list of what's new: Designer Rule based .NET Attribute definitions. It's now possible to specify a rule using fine-grained expressions with an attribute definition to define which elements of a given type will receive the attribute definition. Rules can be assigned to attribute definitions on the project level, to make it even easier to define attribute definitions in bulk for many elements in the project. More information... Revamped Project Settings dialog. Multiple project related properties and settings dialogs have been merged into a single dialog called Project Settings, which makes it easier to configure the various settings related to project elements. It also makes it easier to find features previously not used  by many (e.g. type conversions) More information... Home tab with Quick Start Guides. To make new users feel right at home, we added a home tab with quick start guides which guide you through four main use cases of the designer. System Type Converters. Many common conversions have been implemented by default in system type converters so users don't have to develop their own type converters anymore for these type conversions. Bulk Element Setting Manipulator. To change setting values for multiple project elements, it was a little cumbersome to do that without a lot of clicking and opening various editors. This dialog makes changing settings for multiple elements very easy. EDMX Importer. It's now possible to import entity model data information from an existing Entity Framework EDMX file. Other changes and fixes See for the full list of changes and fixes the online documentation. LLBLGen Pro Runtime Framework WCF Data Services (OData) support has been added. It's now possible to use your LLBLGen Pro runtime framework powered domain layer in a WCF Data Services application using the VS.NET tools for WCF Data Services. WCF Data Services is a Microsoft technology for .NET 4 to expose your domain model using OData. More information... New query specification and execution API: QuerySpec. QuerySpec is our new query specification and execution API as an alternative to Linq and our more low-level API. It's build, like our Linq provider, on top of our lower-level API. More information... SQL Server 2012 support. The SQL Server DQE allows paging using the new SQL Server 2012 style. More information... System Type converters. For a common set of types the LLBLGen Pro runtime framework contains built-in type conversions so you don't need to write your own type converters anymore. Public/NonPublic property support. It's now possible to mark a field / navigator as non-public which is reflected in the runtime framework as an internal/friend property instead of a public property. This way you can hide properties from the public interface of a generated class and still access it through code added to the generated code base. FULL JOIN support. It's now possible to perform FULL JOIN joins using the native query api and QuerySpec. It's left to the developer to check whether the used target database supports FULL (OUTER) JOINs. Using a FULL JOIN with entity fetches is not recommended, and should only be used when both participants in the join aren't the target of the fetch. Dependency Injection Tracing. It's now possible to enable tracing on dependency injection. Enable tracing at level '4' on the traceswitch 'ORMGeneral'. This will emit trace information about which instance of which type got an instance of type T injected into property P. Entity Instances in projections in Linq. It's now possible to return an entity instance in a custom Linq projection. It's now also possible to pass this instance to a method inside the query projection. Inheritance fully supported in this construct. Entity Framework support The Entity Framework has been updated in the recent year with code-first support and a new simpler context api: DbContext (with DbSet). The amount of code to generate is smaller and the context simpler. LLBLGen Pro v3.5 comes with support for DbContext and DbSet and generates code which utilizes these new classes. NHibernate support NHibernate v3.2+ built-in proxy factory factory support. By default the built-in ProxyFactoryFactory is selected. FluentNHibernate Session Manager uses 1.2 syntax. Fluent NHibernate mappings generate a SessionManager which uses the v1.2 syntax for the ProxyFactoryFactory location Optionally emit schema / catalog name in mappings Two settings have been added which allow the user to control whether the catalog name and/or schema name as known in the project in the designer is emitted into the mappings.

    Read the article

  • When should JavaScript generate HTML?

    - by VirtuosiMedia
    I try to generate as little HTML from JavaScript as possible. Instead, I prefer to manipulate existing markup whenever I can and only generate HTML when I need to dynamically insert an element that isn't a good candidate for using Ajax. This, I believe, makes it far easier to maintain the code and quickly make changes to it because the markup is easier to read and trace. My rule of thumb is: HTML is for document structure, CSS is for presentation, JavaScript is for behavior. However, I've seen a lot of JS code that generates mounds of HTML, including entire forms and content-heavy modal dialogs. In general, which method is considered best practice? In what circumstances should JavaScript be used to generate HTML and when should it not?

    Read the article

  • [GEEK SCHOOL] Network Security 1: Securing User Accounts and Passwords in Windows

    - by Matt Klein
    This How-To Geek School class is intended for people who want to learn more about security when using Windows operating systems. You will learn many principles that will help you have a more secure computing experience and will get the chance to use all the important security tools and features that are bundled with Windows. Obviously, we will share everything you need to know about using them effectively. In this first lesson, we will talk about password security; the different ways of logging into Windows and how secure they are. In the proceeding lesson, we will explain where Windows stores all the user names and passwords you enter while working in this operating systems, how safe they are, and how to manage this data. Moving on in the series, we will talk about User Account Control, its role in improving the security of your system, and how to use Windows Defender in order to protect your system from malware. Then, we will talk about the Windows Firewall, how to use it in order to manage the apps that get access to the network and the Internet, and how to create your own filtering rules. After that, we will discuss the SmartScreen Filter – a security feature that gets more and more attention from Microsoft and is now widely used in its Windows 8.x operating systems. Moving on, we will discuss ways to keep your software and apps up-to-date, why this is important and which tools you can use to automate this process as much as possible. Last but not least, we will discuss the Action Center and its role in keeping you informed about what’s going on with your system and share several tips and tricks about how to stay safe when using your computer and the Internet. Let’s get started by discussing everyone’s favorite subject: passwords. The Types of Passwords Found in Windows In Windows 7, you have only local user accounts, which may or may not have a password. For example, you can easily set a blank password for any user account, even if that one is an administrator. The only exception to this rule are business networks where domain policies force all user accounts to use a non-blank password. In Windows 8.x, you have both local accounts and Microsoft accounts. If you would like to learn more about them, don’t hesitate to read the lesson on User Accounts, Groups, Permissions & Their Role in Sharing, in our Windows Networking series. Microsoft accounts are obliged to use a non-blank password due to the fact that a Microsoft account gives you access to Microsoft services. Using a blank password would mean exposing yourself to lots of problems. Local accounts in Windows 8.1 however, can use a blank password. On top of traditional passwords, any user account can create and use a 4-digit PIN or a picture password. These concepts were introduced by Microsoft to speed up the sign in process for the Windows 8.x operating system. However, they do not replace the use of a traditional password and can be used only in conjunction with a traditional user account password. Another type of password that you encounter in Windows operating systems is the Homegroup password. In a typical home network, users can use the Homegroup to easily share resources. A Homegroup can be joined by a Windows device only by using the Homegroup password. If you would like to learn more about the Homegroup and how to use it for network sharing, don’t hesitate to read our Windows Networking series. What to Keep in Mind When Creating Passwords, PINs and Picture Passwords When creating passwords, a PIN, or a picture password for your user account, we would like you keep in mind the following recommendations: Do not use blank passwords, even on the desktop computers in your home. You never know who may gain unwanted access to them. Also, malware can run more easily as administrator because you do not have a password. Trading your security for convenience when logging in is never a good idea. When creating a password, make it at least eight characters long. Make sure that it includes a random mix of upper and lowercase letters, numbers, and symbols. Ideally, it should not be related in any way to your name, username, or company name. Make sure that your passwords do not include complete words from any dictionary. Dictionaries are the first thing crackers use to hack passwords. Do not use the same password for more than one account. All of your passwords should be unique and you should use a system like LastPass, KeePass, Roboform or something similar to keep track of them. When creating a PIN use four different digits to make things slightly harder to crack. When creating a picture password, pick a photo that has at least 10 “points of interests”. Points of interests are areas that serve as a landmark for your gestures. Use a random mixture of gesture types and sequence and make sure that you do not repeat the same gesture twice. Be aware that smudges on the screen could potentially reveal your gestures to others. The Security of Your Password vs. the PIN and the Picture Password Any kind of password can be cracked with enough effort and the appropriate tools. There is no such thing as a completely secure password. However, passwords created using only a few security principles are much harder to crack than others. If you respect the recommendations shared in the previous section of this lesson, you will end up having reasonably secure passwords. Out of all the log in methods in Windows 8.x, the PIN is the easiest to brute force because PINs are restricted to four digits and there are only 10,000 possible unique combinations available. The picture password is more secure than the PIN because it provides many more opportunities for creating unique combinations of gestures. Microsoft have compared the two login options from a security perspective in this post: Signing in with a picture password. In order to discourage brute force attacks against picture passwords and PINs, Windows defaults to your traditional text password after five failed attempts. The PIN and the picture password function only as alternative login methods to Windows 8.x. Therefore, if someone cracks them, he or she doesn’t have access to your user account password. However, that person can use all the apps installed on your Windows 8.x device, access your files, data, and so on. How to Create a PIN in Windows 8.x If you log in to a Windows 8.x device with a user account that has a non-blank password, then you can create a 4-digit PIN for it, to use it as a complementary login method. In order to create one, you need to go to “PC Settings”. If you don’t know how, then press Windows + C on your keyboard or flick from the right edge of the screen, on a touch-enabled device, then press “Settings”. The Settings charm is now open. Click or tap the link that says “Change PC settings”, on the bottom of the charm. In PC settings, go to Accounts and then to “Sign-in options”. Here you will find all the necessary options for changing your existing password, creating a PIN, or a picture password. To create a PIN, press the “Add” button in the PIN section. The “Create a PIN” wizard is started and you are asked to enter the password of your user account. Type it and press “OK”. Now you are asked to enter a 4-digit pin in the “Enter PIN” and “Confirm PIN” fields. The PIN has been created and you can now use it to log in to Windows. How to Create a Picture Password in Windows 8.x If you log in to a Windows 8.x device with a user account that has a non-blank password, then you can also create a picture password and use it as a complementary login method. In order to create one, you need to go to “PC settings”. In PC Settings, go to Accounts and then to “Sign-in options”. Here you will find all the necessary options for changing your existing password, creating a PIN, or a picture password. To create a picture password, press the “Add” button in the “Picture password” section. The “Create a picture password” wizard is started and you are asked to enter the password of your user account. You are shown a guide on how the picture password works. Take a few seconds to watch it and learn the gestures that can be used for your picture password. You will learn that you can create a combination of circles, straight lines, and taps. When ready, press “Choose picture”. Browse your Windows 8.x device and select the picture you want to use for your password and press “Open”. Now you can drag the picture to position it the way you want. When you like how the picture is positioned, press “Use this picture” on the left. If you are not happy with the picture, press “Choose new picture” and select a new one, as shown during the previous step. After you have confirmed that you want to use this picture, you are asked to set up your gestures for the picture password. Draw three gestures on the picture, any combination you wish. Please remember that you can use only three gestures: circles, straight lines, and taps. Once you have drawn those three gestures, you are asked to confirm. Draw the same gestures one more time. If everything goes well, you are informed that you have created your picture password and that you can use it the next time you sign in to Windows. If you don’t confirm the gestures correctly, you will be asked to try again, until you draw the same gestures twice. To close the picture password wizard, press “Finish”. Where Does Windows Store Your Passwords? Are They Safe? All the passwords that you enter in Windows and save for future use are stored in the Credential Manager. This tool is a vault with the usernames and passwords that you use to log on to your computer, to other computers on the network, to apps from the Windows Store, or to websites using Internet Explorer. By storing these credentials, Windows can automatically log you the next time you access the same app, network share, or website. Everything that is stored in the Credential Manager is encrypted for your protection.

    Read the article

  • Formal Languages, Inductive Proofs &amp; Regular Expressions

    - by MarkPearl
    So I am slogging away at my UNISA stuff. I have just finished doing the initial once non stop read through the first 11 chapters of my COS 201 Textbook - “Introduction to Computer Theory 2nd Edition” by Daniel Cohen. It has been an interesting couple of days, with familiar concepts coming up as well as some new territory. In this posting I am going to cover the first couple of chapters of the book. Let start with Formal Languages… What exactly is a formal language? Pretty much a no duh question for me but still a good one to ask – a formal language is a language that is defined in a precise mathematical way. Does that mean that the English language is a formal language? I would say no – and my main motivation for this is that one can have an English sentence that is correct grammatically that is also ambiguous. For example the ambiguous sentence: "I once shot an elephant in my pyjamas.” For this and possibly many other reasons that I am unaware of, English is termed a “Natural Language”. So why the importance of formal languages in computer science? Again a no duh question in my mind… If we want computers to be effective and useful tools then we need them to be able to evaluate a series of commands in some form of language that when interpreted by the device no confusion will exist as to what we were requesting. Imagine the mayhem that would exist if a computer misinterpreted a command to print a document and instead decided to delete it. So what is a Formal Language made up of… For my study purposes a language is made up of a finite alphabet. For a formal language to exist there needs to be a specification on the language that will describe whether a string of characters has membership in the language or not. There are two basic ways to do this: By a “machine” that will recognize strings of the language (e.g. Finite Automata). By a rule that describes how strings of a language can be formed (e.g. Regular Expressions). When we use the phrase “string of characters”, we can also be referring to a “word”. What is an Inductive Proof? So I am not to far into my textbook and of course it starts referring to proofs and different types. I have had to go through several different approaches of proofs in the past, but I can never remember their formal names , so when I saw “inductive proof” I thought to myself – what the heck is that? Google to the rescue… An inductive proof is like a normal proof but it employs a neat trick which allows you to prove a statement about an arbitrary number n by first proving it is true when n is 1 and then assuming it is true for n=k and showing it is true for n=k+1. The idea is that if you want to show that someone can climb to the nth floor of a fire escape, you need only show that you can climb the ladder up to the fire escape (n=1) and then show that you know how to climb the stairs from any level of the fire escape (n=k) to the next level (n=k+1). Does this sound like a form of recursion? No surprise then that in the same chapter they deal with recursive definitions. An example of a recursive definition for the language EVEN would the 3 rules below: 2 is in EVEN If x is in EVEN then so is x+2 The only elements in the set EVEN are those that be produced by the rules above. Nothing to exciting… So if a definition for a language is done recursively, then it makes sense that the language can be proved using induction. Regular Expressions So I am wondering to myself what use is this all – in fact – I find this the biggest challenge to any university material is that it is quite hard to find the immediate practical applications of some theory in real life stuff. How great was my joy when I suddenly saw the word regular expression being introduced. I had been introduced to regular expressions on Stack Overflow where I was trying to recognize if some text measurement put in by a user was in a valid form or not. For instance, the imperial system of measurement where you have feet and inches can be represented in so many different ways. I had eventually turned to regular expressions as an easy way to check if my parser could correctly parse the text or not and convert it to a normalize measurement. So some rules about languages and regular expressions… Any finite language can be represented by at least one if not more regular expressions A regular expressions is almost a rule syntax for expressing how regular languages can be formed regular expressions are cool For a regular expression to be valid for a language it must be able to generate all the words in the language and no other words. This is important. It doesn’t help me if my regular expression parses 100% of my measurement texts but also lets one or two invalid texts to pass as well. Okay, so this posting jumps around a bit – but introduces some very basic fundamentals for the subject which will be built on in later postings… Time to go and do some practical examples now…

    Read the article

  • Uploading and Importing CSV file to SQL Server in ASP.NET WebForms

    - by Vincent Maverick Durano
    Few weeks ago I was working with a small internal project  that involves importing CSV file to Sql Server database and thought I'd share the simple implementation that I did on the project. In this post I will demonstrate how to upload and import CSV file to SQL Server database. As some may have already know, importing CSV file to SQL Server is easy and simple but difficulties arise when the CSV file contains, many columns with different data types. Basically, the provider cannot differentiate data types between the columns or the rows, blindly it will consider them as a data type based on first few rows and leave all the data which does not match the data type. To overcome this problem, I used schema.ini file to define the data type of the CSV file and allow the provider to read that and recognize the exact data types of each column. Now what is schema.ini? Taken from the documentation: The Schema.ini is a information file, used to define the data structure and format of each column that contains data in the CSV file. If schema.ini file exists in the directory, Microsoft.Jet.OLEDB provider automatically reads it and recognizes the data type information of each column in the CSV file. Thus, the provider intelligently avoids the misinterpretation of data types before inserting the data into the database. For more information see: http://msdn.microsoft.com/en-us/library/ms709353%28VS.85%29.aspx Points to remember before creating schema.ini:   1. The schema information file, must always named as 'schema.ini'.   2. The schema.ini file must be kept in the same directory where the CSV file exists.   3. The schema.ini file must be created before reading the CSV file.   4. The first line of the schema.ini, must the name of the CSV file, followed by the properties of the CSV file, and then the properties of the each column in the CSV file. Here's an example of how the schema looked like: [Employee.csv] ColNameHeader=False Format=CSVDelimited DateTimeFormat=dd-MMM-yyyy Col1=EmployeeID Long Col2=EmployeeFirstName Text Width 100 Col3=EmployeeLastName Text Width 50 Col4=EmployeeEmailAddress Text Width 50 To get started lets's go a head and create a simple blank database. Just for the purpose of this demo I created a database called TestDB. After creating the database then lets go a head and fire up Visual Studio and then create a new WebApplication project. Under the root application create a folder called UploadedCSVFiles and then place the schema.ini on that folder. The uploaded CSV files will be stored in this folder after the user imports the file. Now add a WebForm in the project and set up the HTML mark up and add one (1) FileUpload control one(1)Button and three (3) Label controls. After that we can now proceed with the codes for uploading and importing the CSV file to SQL Server database. Here are the full code blocks below: 1: using System; 2: using System.Data; 3: using System.Data.SqlClient; 4: using System.Data.OleDb; 5: using System.IO; 6: using System.Text; 7:   8: namespace WebApplication1 9: { 10: public partial class CSVToSQLImporting : System.Web.UI.Page 11: { 12: private string GetConnectionString() 13: { 14: return System.Configuration.ConfigurationManager.ConnectionStrings["DBConnectionString"].ConnectionString; 15: } 16: private void CreateDatabaseTable(DataTable dt, string tableName) 17: { 18:   19: string sqlQuery = string.Empty; 20: string sqlDBType = string.Empty; 21: string dataType = string.Empty; 22: int maxLength = 0; 23: StringBuilder sb = new StringBuilder(); 24:   25: sb.AppendFormat(string.Format("CREATE TABLE {0} (", tableName)); 26:   27: for (int i = 0; i < dt.Columns.Count; i++) 28: { 29: dataType = dt.Columns[i].DataType.ToString(); 30: if (dataType == "System.Int32") 31: { 32: sqlDBType = "INT"; 33: } 34: else if (dataType == "System.String") 35: { 36: sqlDBType = "NVARCHAR"; 37: maxLength = dt.Columns[i].MaxLength; 38: } 39:   40: if (maxLength > 0) 41: { 42: sb.AppendFormat(string.Format(" {0} {1} ({2}), ", dt.Columns[i].ColumnName, sqlDBType, maxLength)); 43: } 44: else 45: { 46: sb.AppendFormat(string.Format(" {0} {1}, ", dt.Columns[i].ColumnName, sqlDBType)); 47: } 48: } 49:   50: sqlQuery = sb.ToString(); 51: sqlQuery = sqlQuery.Trim().TrimEnd(','); 52: sqlQuery = sqlQuery + " )"; 53:   54: using (SqlConnection sqlConn = new SqlConnection(GetConnectionString())) 55: { 56: sqlConn.Open(); 57: SqlCommand sqlCmd = new SqlCommand(sqlQuery, sqlConn); 58: sqlCmd.ExecuteNonQuery(); 59: sqlConn.Close(); 60: } 61:   62: } 63: private void LoadDataToDatabase(string tableName, string fileFullPath, string delimeter) 64: { 65: string sqlQuery = string.Empty; 66: StringBuilder sb = new StringBuilder(); 67:   68: sb.AppendFormat(string.Format("BULK INSERT {0} ", tableName)); 69: sb.AppendFormat(string.Format(" FROM '{0}'", fileFullPath)); 70: sb.AppendFormat(string.Format(" WITH ( FIELDTERMINATOR = '{0}' , ROWTERMINATOR = '\n' )", delimeter)); 71:   72: sqlQuery = sb.ToString(); 73:   74: using (SqlConnection sqlConn = new SqlConnection(GetConnectionString())) 75: { 76: sqlConn.Open(); 77: SqlCommand sqlCmd = new SqlCommand(sqlQuery, sqlConn); 78: sqlCmd.ExecuteNonQuery(); 79: sqlConn.Close(); 80: } 81: } 82: protected void Page_Load(object sender, EventArgs e) 83: { 84:   85: } 86: protected void BTNImport_Click(object sender, EventArgs e) 87: { 88: if (FileUpload1.HasFile) 89: { 90: FileInfo fileInfo = new FileInfo(FileUpload1.PostedFile.FileName); 91: if (fileInfo.Name.Contains(".csv")) 92: { 93:   94: string fileName = fileInfo.Name.Replace(".csv", "").ToString(); 95: string csvFilePath = Server.MapPath("UploadedCSVFiles") + "\\" + fileInfo.Name; 96:   97: //Save the CSV file in the Server inside 'MyCSVFolder' 98: FileUpload1.SaveAs(csvFilePath); 99:   100: //Fetch the location of CSV file 101: string filePath = Server.MapPath("UploadedCSVFiles") + "\\"; 102: string strSql = "SELECT * FROM [" + fileInfo.Name + "]"; 103: string strCSVConnString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filePath + ";" + "Extended Properties='text;HDR=YES;'"; 104:   105: // load the data from CSV to DataTable 106:   107: OleDbDataAdapter adapter = new OleDbDataAdapter(strSql, strCSVConnString); 108: DataTable dtCSV = new DataTable(); 109: DataTable dtSchema = new DataTable(); 110:   111: adapter.FillSchema(dtCSV, SchemaType.Mapped); 112: adapter.Fill(dtCSV); 113:   114: if (dtCSV.Rows.Count > 0) 115: { 116: CreateDatabaseTable(dtCSV, fileName); 117: Label2.Text = string.Format("The table ({0}) has been successfully created to the database.", fileName); 118:   119: string fileFullPath = filePath + fileInfo.Name; 120: LoadDataToDatabase(fileName, fileFullPath, ","); 121:   122: Label1.Text = string.Format("({0}) records has been loaded to the table {1}.", dtCSV.Rows.Count, fileName); 123: } 124: else 125: { 126: LBLError.Text = "File is empty."; 127: } 128: } 129: else 130: { 131: LBLError.Text = "Unable to recognize file."; 132: } 133:   134: } 135: } 136: } 137: } The code above consists of three (3) private methods which are the GetConnectionString(), CreateDatabaseTable() and LoadDataToDatabase(). The GetConnectionString() is a method that returns a string. This method basically gets the connection string that is configured in the web.config file. The CreateDatabaseTable() is method that accepts two (2) parameters which are the DataTable and the filename. As the method name already suggested, this method automatically create a Table to the database based on the source DataTable and the filename of the CSV file. The LoadDataToDatabase() is a method that accepts three (3) parameters which are the tableName, fileFullPath and delimeter value. This method is where the actual saving or importing of data from CSV to SQL server happend. The codes at BTNImport_Click event handles the uploading of CSV file to the specified location and at the same time this is where the CreateDatabaseTable() and LoadDataToDatabase() are being called. If you notice I also added some basic trappings and validations within that event. Now to test the importing utility then let's create a simple data in a CSV format. Just for the simplicity of this demo let's create a CSV file and name it as "Employee" and add some data on it. Here's an example below: 1,VMS,Durano,[email protected] 2,Jennifer,Cortes,[email protected] 3,Xhaiden,Durano,[email protected] 4,Angel,Santos,[email protected] 5,Kier,Binks,[email protected] 6,Erika,Bird,[email protected] 7,Vianne,Durano,[email protected] 8,Lilibeth,Tree,[email protected] 9,Bon,Bolger,[email protected] 10,Brian,Jones,[email protected] Now save the newly created CSV file in some location in your hard drive. Okay let's run the application and browse the CSV file that we have just created. Take a look at the sample screen shots below: After browsing the CSV file. After clicking the Import Button Now if we look at the database that we have created earlier you'll notice that the Employee table is created with the imported data on it. See below screen shot.   That's it! I hope someone find this post useful! Technorati Tags: ASP.NET,CSV,SQL,C#,ADO.NET

    Read the article

< Previous Page | 115 116 117 118 119 120 121 122 123 124 125 126  | Next Page >