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  • Agile Development

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

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  • Did I lose my RAID again?

    - by BarsMonster
    Hi! A little history: 2 years ago I was really excited to find out that mdadm is so powerful that it even can reshape arrays, so you can start with a smaller array and then grow it as you need. I've bought 3x1Tb drives and made a RAID-5. It was fine for a year. Then I bought 2x more, and tried to reshape to RAID-6 out of 5 drives, and due to some mess with superblock versions, lost all content. Had to rebuild it from scratch, but 2Tb of data were gone. Yesterday I bought 2 more drives, and this time I had everything: properly built array, UPS. I've disabled write intent map, added 2 new drives as spares and run a command to grow array to 7-disks. It started working, but speed was ridiculously slow, ~100kb/sec. After processing first 37Mb at such an amazing speed, one of old HDDs fails. I properly shutdown the PC and disconnected the failed drive. After bootup it appeared that it recreated the intent map as it was still in mdadm config, so I removed it from config and rebooted again. Now all I see is that all mdadm processes deadlock, and don't do anything. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1937 root 20 0 12992 608 444 D 0 0.1 0:00.00 mdadm 2283 root 20 0 12992 852 704 D 0 0.1 0:00.01 mdadm 2287 root 20 0 0 0 0 D 0 0.0 0:00.01 md0_reshape 2288 root 18 -2 12992 820 676 D 0 0.1 0:00.01 mdadm And all I see in mdstat is: $ cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active raid6 sdb1[1] sdg1[4] sdf1[7] sde1[6] sdd1[0] sdc1[5] 2929683456 blocks super 1.2 level 6, 1024k chunk, algorithm 2 [7/6] [UU_UUUU] [>....................] reshape = 0.0% (37888/976561152) finish=567604147.2min speed=0K/sec I've already tried mdadm 2.6.7, 3.1.4 and 3.2 - nothing helps. Did I lose my data again? Any suggestions on how can I make this work? OS is Ubuntu Server 10.04.2. PS. Needless to say, the data is inaccessible - I cannot mount /dev/md0 to save the most valuable data. You can see my disappointment - the very specific thing I was excited about failed twice taking 5Tb of my data with it. Update: It appears there is some nice info in kern.log: 21:38:48 ...: [ 166.522055] raid5: reshape will continue 21:38:48 ...: [ 166.522085] raid5: device sdb1 operational as raid disk 1 21:38:48 ...: [ 166.522091] raid5: device sdg1 operational as raid disk 4 21:38:48 ...: [ 166.522097] raid5: device sdf1 operational as raid disk 5 21:38:48 ...: [ 166.522102] raid5: device sde1 operational as raid disk 6 21:38:48 ...: [ 166.522107] raid5: device sdd1 operational as raid disk 0 21:38:48 ...: [ 166.522111] raid5: device sdc1 operational as raid disk 3 21:38:48 ...: [ 166.523942] raid5: allocated 7438kB for md0 21:38:48 ...: [ 166.524041] 1: w=1 pa=2 pr=5 m=2 a=2 r=7 op1=0 op2=0 21:38:48 ...: [ 166.524050] 4: w=2 pa=2 pr=5 m=2 a=2 r=7 op1=0 op2=0 21:38:48 ...: [ 166.524056] 5: w=3 pa=2 pr=5 m=2 a=2 r=7 op1=0 op2=0 21:38:48 ...: [ 166.524062] 6: w=4 pa=2 pr=5 m=2 a=2 r=7 op1=0 op2=0 21:38:48 ...: [ 166.524068] 0: w=5 pa=2 pr=5 m=2 a=2 r=7 op1=0 op2=0 21:38:48 ...: [ 166.524073] 3: w=6 pa=2 pr=5 m=2 a=2 r=7 op1=0 op2=0 21:38:48 ...: [ 166.524079] raid5: raid level 6 set md0 active with 6 out of 7 devices, algorithm 2 21:38:48 ...: [ 166.524519] RAID5 conf printout: 21:38:48 ...: [ 166.524523] --- rd:7 wd:6 21:38:48 ...: [ 166.524528] disk 0, o:1, dev:sdd1 21:38:48 ...: [ 166.524532] disk 1, o:1, dev:sdb1 21:38:48 ...: [ 166.524537] disk 3, o:1, dev:sdc1 21:38:48 ...: [ 166.524541] disk 4, o:1, dev:sdg1 21:38:48 ...: [ 166.524545] disk 5, o:1, dev:sdf1 21:38:48 ...: [ 166.524550] disk 6, o:1, dev:sde1 21:38:48 ...: [ 166.524553] ...ok start reshape thread 21:38:48 ...: [ 166.524727] md0: detected capacity change from 0 to 2999995858944 21:38:48 ...: [ 166.524735] md: reshape of RAID array md0 21:38:48 ...: [ 166.524740] md: minimum _guaranteed_ speed: 1000 KB/sec/disk. 21:38:48 ...: [ 166.524745] md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for reshape. 21:38:48 ...: [ 166.524756] md: using 128k window, over a total of 976561152 blocks. 21:39:05 ...: [ 166.525013] md0: 21:42:04 ...: [ 362.520063] INFO: task mdadm:1937 blocked for more than 120 seconds. 21:42:04 ...: [ 362.520068] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:42:04 ...: [ 362.520073] mdadm D 00000000ffffffff 0 1937 1 0x00000000 21:42:04 ...: [ 362.520083] ffff88002ef4f5d8 0000000000000082 0000000000015bc0 0000000000015bc0 21:42:04 ...: [ 362.520092] ffff88002eb5b198 ffff88002ef4ffd8 0000000000015bc0 ffff88002eb5ade0 21:42:04 ...: [ 362.520100] 0000000000015bc0 ffff88002ef4ffd8 0000000000015bc0 ffff88002eb5b198 21:42:04 ...: [ 362.520107] Call Trace: 21:42:04 ...: [ 362.520133] [<ffffffffa0224892>] get_active_stripe+0x312/0x3f0 [raid456] 21:42:04 ...: [ 362.520148] [<ffffffff81059ae0>] ? default_wake_function+0x0/0x20 21:42:04 ...: [ 362.520159] [<ffffffffa0228413>] make_request+0x243/0x4b0 [raid456] 21:42:04 ...: [ 362.520169] [<ffffffffa0221a90>] ? release_stripe+0x50/0x70 [raid456] 21:42:04 ...: [ 362.520179] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:42:04 ...: [ 362.520188] [<ffffffff81414df0>] md_make_request+0xc0/0x130 21:42:04 ...: [ 362.520194] [<ffffffff81414df0>] ? md_make_request+0xc0/0x130 21:42:04 ...: [ 362.520205] [<ffffffff8129f8c1>] generic_make_request+0x1b1/0x4f0 21:42:04 ...: [ 362.520214] [<ffffffff810f6515>] ? mempool_alloc_slab+0x15/0x20 21:42:04 ...: [ 362.520222] [<ffffffff8116c2ec>] ? alloc_buffer_head+0x1c/0x60 21:42:04 ...: [ 362.520230] [<ffffffff8129fc80>] submit_bio+0x80/0x110 21:42:04 ...: [ 362.520236] [<ffffffff8116c849>] submit_bh+0xf9/0x140 21:42:04 ...: [ 362.520244] [<ffffffff8116f124>] block_read_full_page+0x274/0x3b0 21:42:04 ...: [ 362.520251] [<ffffffff81172c90>] ? blkdev_get_block+0x0/0x70 21:42:04 ...: [ 362.520258] [<ffffffff8110d875>] ? __inc_zone_page_state+0x35/0x40 21:42:04 ...: [ 362.520265] [<ffffffff810f46d8>] ? add_to_page_cache_locked+0xe8/0x160 21:42:04 ...: [ 362.520272] [<ffffffff81173d78>] blkdev_readpage+0x18/0x20 21:42:04 ...: [ 362.520279] [<ffffffff810f484b>] __read_cache_page+0x7b/0xe0 21:42:04 ...: [ 362.520285] [<ffffffff81173d60>] ? blkdev_readpage+0x0/0x20 21:42:04 ...: [ 362.520290] [<ffffffff81173d60>] ? blkdev_readpage+0x0/0x20 21:42:04 ...: [ 362.520297] [<ffffffff810f57dc>] do_read_cache_page+0x3c/0x120 21:42:04 ...: [ 362.520304] [<ffffffff810f5909>] read_cache_page_async+0x19/0x20 21:42:04 ...: [ 362.520310] [<ffffffff810f591e>] read_cache_page+0xe/0x20 21:42:04 ...: [ 362.520317] [<ffffffff811a6cb0>] read_dev_sector+0x30/0xa0 21:42:04 ...: [ 362.520324] [<ffffffff811a7fcd>] amiga_partition+0x6d/0x460 21:42:04 ...: [ 362.520331] [<ffffffff811a7938>] check_partition+0x138/0x190 21:42:04 ...: [ 362.520338] [<ffffffff811a7a7a>] rescan_partitions+0xea/0x2f0 21:42:04 ...: [ 362.520344] [<ffffffff811744c7>] __blkdev_get+0x267/0x3d0 21:42:04 ...: [ 362.520350] [<ffffffff81174650>] ? blkdev_open+0x0/0xc0 21:42:04 ...: [ 362.520356] [<ffffffff81174640>] blkdev_get+0x10/0x20 21:42:04 ...: [ 362.520362] [<ffffffff811746c1>] blkdev_open+0x71/0xc0 21:42:04 ...: [ 362.520369] [<ffffffff811419f3>] __dentry_open+0x113/0x370 21:42:04 ...: [ 362.520377] [<ffffffff81253f8f>] ? security_inode_permission+0x1f/0x30 21:42:04 ...: [ 362.520385] [<ffffffff8114de3f>] ? inode_permission+0xaf/0xd0 21:42:04 ...: [ 362.520391] [<ffffffff81141d67>] nameidata_to_filp+0x57/0x70 21:42:04 ...: [ 362.520398] [<ffffffff8115207a>] do_filp_open+0x2da/0xba0 21:42:04 ...: [ 362.520406] [<ffffffff811134a8>] ? unmap_vmas+0x178/0x310 21:42:04 ...: [ 362.520414] [<ffffffff8115dbfa>] ? alloc_fd+0x10a/0x150 21:42:04 ...: [ 362.520421] [<ffffffff81141769>] do_sys_open+0x69/0x170 21:42:04 ...: [ 362.520428] [<ffffffff811418b0>] sys_open+0x20/0x30 21:42:04 ...: [ 362.520437] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:42:04 ...: [ 362.520446] INFO: task mdadm:2283 blocked for more than 120 seconds. 21:42:04 ...: [ 362.520450] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:42:04 ...: [ 362.520454] mdadm D 0000000000000000 0 2283 2212 0x00000000 21:42:04 ...: [ 362.520462] ffff88002cca7d98 0000000000000086 0000000000015bc0 0000000000015bc0 21:42:04 ...: [ 362.520470] ffff88002ededf78 ffff88002cca7fd8 0000000000015bc0 ffff88002ededbc0 21:42:04 ...: [ 362.520478] 0000000000015bc0 ffff88002cca7fd8 0000000000015bc0 ffff88002ededf78 21:42:04 ...: [ 362.520485] Call Trace: 21:42:04 ...: [ 362.520495] [<ffffffff81543a97>] __mutex_lock_slowpath+0xf7/0x180 21:42:04 ...: [ 362.520502] [<ffffffff8154397b>] mutex_lock+0x2b/0x50 21:42:04 ...: [ 362.520508] [<ffffffff8117404d>] __blkdev_put+0x3d/0x190 21:42:04 ...: [ 362.520514] [<ffffffff811741b0>] blkdev_put+0x10/0x20 21:42:04 ...: [ 362.520520] [<ffffffff811741f3>] blkdev_close+0x33/0x60 21:42:04 ...: [ 362.520527] [<ffffffff81145375>] __fput+0xf5/0x210 21:42:04 ...: [ 362.520534] [<ffffffff811454b5>] fput+0x25/0x30 21:42:04 ...: [ 362.520540] [<ffffffff811415ad>] filp_close+0x5d/0x90 21:42:04 ...: [ 362.520546] [<ffffffff81141697>] sys_close+0xb7/0x120 21:42:04 ...: [ 362.520553] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:42:04 ...: [ 362.520559] INFO: task md0_reshape:2287 blocked for more than 120 seconds. 21:42:04 ...: [ 362.520563] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:42:04 ...: [ 362.520567] md0_reshape D ffff88003aee96f0 0 2287 2 0x00000000 21:42:04 ...: [ 362.520575] ffff88003cf05a70 0000000000000046 0000000000015bc0 0000000000015bc0 21:42:04 ...: [ 362.520582] ffff88003aee9aa8 ffff88003cf05fd8 0000000000015bc0 ffff88003aee96f0 21:42:04 ...: [ 362.520590] 0000000000015bc0 ffff88003cf05fd8 0000000000015bc0 ffff88003aee9aa8 21:42:04 ...: [ 362.520597] Call Trace: 21:42:04 ...: [ 362.520608] [<ffffffffa0224892>] get_active_stripe+0x312/0x3f0 [raid456] 21:42:04 ...: [ 362.520616] [<ffffffff81059ae0>] ? default_wake_function+0x0/0x20 21:42:04 ...: [ 362.520626] [<ffffffffa0226f80>] reshape_request+0x4c0/0x9a0 [raid456] 21:42:04 ...: [ 362.520634] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:42:04 ...: [ 362.520644] [<ffffffffa022777a>] sync_request+0x31a/0x3a0 [raid456] 21:42:04 ...: [ 362.520651] [<ffffffff81052713>] ? __wake_up+0x53/0x70 21:42:04 ...: [ 362.520658] [<ffffffff814156b1>] md_do_sync+0x621/0xbb0 21:42:04 ...: [ 362.520668] [<ffffffff810387b9>] ? default_spin_lock_flags+0x9/0x10 21:42:04 ...: [ 362.520675] [<ffffffff8141640c>] md_thread+0x5c/0x130 21:42:04 ...: [ 362.520681] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:42:04 ...: [ 362.520688] [<ffffffff814163b0>] ? md_thread+0x0/0x130 21:42:04 ...: [ 362.520694] [<ffffffff81084416>] kthread+0x96/0xa0 21:42:04 ...: [ 362.520701] [<ffffffff810131ea>] child_rip+0xa/0x20 21:42:04 ...: [ 362.520707] [<ffffffff81084380>] ? kthread+0x0/0xa0 21:42:04 ...: [ 362.520713] [<ffffffff810131e0>] ? child_rip+0x0/0x20 21:42:04 ...: [ 362.520718] INFO: task mdadm:2288 blocked for more than 120 seconds. 21:42:04 ...: [ 362.520721] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:42:04 ...: [ 362.520725] mdadm D 0000000000000000 0 2288 1 0x00000000 21:42:04 ...: [ 362.520733] ffff88002cca9c18 0000000000000086 0000000000015bc0 0000000000015bc0 21:42:04 ...: [ 362.520741] ffff88003aee83b8 ffff88002cca9fd8 0000000000015bc0 ffff88003aee8000 21:42:04 ...: [ 362.520748] 0000000000015bc0 ffff88002cca9fd8 0000000000015bc0 ffff88003aee83b8 21:42:04 ...: [ 362.520755] Call Trace: 21:42:04 ...: [ 362.520763] [<ffffffff81543a97>] __mutex_lock_slowpath+0xf7/0x180 21:42:04 ...: [ 362.520771] [<ffffffff812a6d50>] ? exact_match+0x0/0x10 21:42:04 ...: [ 362.520777] [<ffffffff8154397b>] mutex_lock+0x2b/0x50 21:42:04 ...: [ 362.520783] [<ffffffff811742c8>] __blkdev_get+0x68/0x3d0 21:42:04 ...: [ 362.520790] [<ffffffff81174650>] ? blkdev_open+0x0/0xc0 21:42:04 ...: [ 362.520795] [<ffffffff81174640>] blkdev_get+0x10/0x20 21:42:04 ...: [ 362.520801] [<ffffffff811746c1>] blkdev_open+0x71/0xc0 21:42:04 ...: [ 362.520808] [<ffffffff811419f3>] __dentry_open+0x113/0x370 21:42:04 ...: [ 362.520815] [<ffffffff81253f8f>] ? security_inode_permission+0x1f/0x30 21:42:04 ...: [ 362.520821] [<ffffffff8114de3f>] ? inode_permission+0xaf/0xd0 21:42:04 ...: [ 362.520828] [<ffffffff81141d67>] nameidata_to_filp+0x57/0x70 21:42:04 ...: [ 362.520834] [<ffffffff8115207a>] do_filp_open+0x2da/0xba0 21:42:04 ...: [ 362.520841] [<ffffffff810ff0e1>] ? lru_cache_add_lru+0x21/0x40 21:42:04 ...: [ 362.520848] [<ffffffff8111109c>] ? do_anonymous_page+0x11c/0x330 21:42:04 ...: [ 362.520855] [<ffffffff81115d5f>] ? handle_mm_fault+0x31f/0x3c0 21:42:04 ...: [ 362.520862] [<ffffffff8115dbfa>] ? alloc_fd+0x10a/0x150 21:42:04 ...: [ 362.520868] [<ffffffff81141769>] do_sys_open+0x69/0x170 21:42:04 ...: [ 362.520874] [<ffffffff811418b0>] sys_open+0x20/0x30 21:42:04 ...: [ 362.520882] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:44:04 ...: [ 482.520065] INFO: task mdadm:1937 blocked for more than 120 seconds. 21:44:04 ...: [ 482.520071] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:44:04 ...: [ 482.520077] mdadm D 00000000ffffffff 0 1937 1 0x00000000 21:44:04 ...: [ 482.520087] ffff88002ef4f5d8 0000000000000082 0000000000015bc0 0000000000015bc0 21:44:04 ...: [ 482.520096] ffff88002eb5b198 ffff88002ef4ffd8 0000000000015bc0 ffff88002eb5ade0 21:44:04 ...: [ 482.520104] 0000000000015bc0 ffff88002ef4ffd8 0000000000015bc0 ffff88002eb5b198 21:44:04 ...: [ 482.520112] Call Trace: 21:44:04 ...: [ 482.520139] [<ffffffffa0224892>] get_active_stripe+0x312/0x3f0 [raid456] 21:44:04 ...: [ 482.520154] [<ffffffff81059ae0>] ? default_wake_function+0x0/0x20 21:44:04 ...: [ 482.520165] [<ffffffffa0228413>] make_request+0x243/0x4b0 [raid456] 21:44:04 ...: [ 482.520175] [<ffffffffa0221a90>] ? release_stripe+0x50/0x70 [raid456] 21:44:04 ...: [ 482.520185] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:44:04 ...: [ 482.520194] [<ffffffff81414df0>] md_make_request+0xc0/0x130 21:44:04 ...: [ 482.520201] [<ffffffff81414df0>] ? md_make_request+0xc0/0x130 21:44:04 ...: [ 482.520212] [<ffffffff8129f8c1>] generic_make_request+0x1b1/0x4f0 21:44:04 ...: [ 482.520221] [<ffffffff810f6515>] ? mempool_alloc_slab+0x15/0x20 21:44:04 ...: [ 482.520229] [<ffffffff8116c2ec>] ? alloc_buffer_head+0x1c/0x60 21:44:04 ...: [ 482.520237] [<ffffffff8129fc80>] submit_bio+0x80/0x110 21:44:04 ...: [ 482.520244] [<ffffffff8116c849>] submit_bh+0xf9/0x140 21:44:04 ...: [ 482.520252] [<ffffffff8116f124>] block_read_full_page+0x274/0x3b0 21:44:04 ...: [ 482.520258] [<ffffffff81172c90>] ? blkdev_get_block+0x0/0x70 21:44:04 ...: [ 482.520266] [<ffffffff8110d875>] ? __inc_zone_page_state+0x35/0x40 21:44:04 ...: [ 482.520273] [<ffffffff810f46d8>] ? add_to_page_cache_locked+0xe8/0x160 21:44:04 ...: [ 482.520280] [<ffffffff81173d78>] blkdev_readpage+0x18/0x20 21:44:04 ...: [ 482.520286] [<ffffffff810f484b>] __read_cache_page+0x7b/0xe0 21:44:04 ...: [ 482.520293] [<ffffffff81173d60>] ? blkdev_readpage+0x0/0x20 21:44:04 ...: [ 482.520299] [<ffffffff81173d60>] ? blkdev_readpage+0x0/0x20 21:44:04 ...: [ 482.520306] [<ffffffff810f57dc>] do_read_cache_page+0x3c/0x120 21:44:04 ...: [ 482.520313] [<ffffffff810f5909>] read_cache_page_async+0x19/0x20 21:44:04 ...: [ 482.520319] [<ffffffff810f591e>] read_cache_page+0xe/0x20 21:44:04 ...: [ 482.520327] [<ffffffff811a6cb0>] read_dev_sector+0x30/0xa0 21:44:04 ...: [ 482.520334] [<ffffffff811a7fcd>] amiga_partition+0x6d/0x460 21:44:04 ...: [ 482.520341] [<ffffffff811a7938>] check_partition+0x138/0x190 21:44:04 ...: [ 482.520348] [<ffffffff811a7a7a>] rescan_partitions+0xea/0x2f0 21:44:04 ...: [ 482.520355] [<ffffffff811744c7>] __blkdev_get+0x267/0x3d0 21:44:04 ...: [ 482.520361] [<ffffffff81174650>] ? blkdev_open+0x0/0xc0 21:44:04 ...: [ 482.520367] [<ffffffff81174640>] blkdev_get+0x10/0x20 21:44:04 ...: [ 482.520373] [<ffffffff811746c1>] blkdev_open+0x71/0xc0 21:44:04 ...: [ 482.520380] [<ffffffff811419f3>] __dentry_open+0x113/0x370 21:44:04 ...: [ 482.520388] [<ffffffff81253f8f>] ? security_inode_permission+0x1f/0x30 21:44:04 ...: [ 482.520396] [<ffffffff8114de3f>] ? inode_permission+0xaf/0xd0 21:44:04 ...: [ 482.520403] [<ffffffff81141d67>] nameidata_to_filp+0x57/0x70 21:44:04 ...: [ 482.520410] [<ffffffff8115207a>] do_filp_open+0x2da/0xba0 21:44:04 ...: [ 482.520417] [<ffffffff811134a8>] ? unmap_vmas+0x178/0x310 21:44:04 ...: [ 482.520426] [<ffffffff8115dbfa>] ? alloc_fd+0x10a/0x150 21:44:04 ...: [ 482.520432] [<ffffffff81141769>] do_sys_open+0x69/0x170 21:44:04 ...: [ 482.520438] [<ffffffff811418b0>] sys_open+0x20/0x30 21:44:04 ...: [ 482.520447] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:44:04 ...: [ 482.520458] INFO: task mdadm:2283 blocked for more than 120 seconds. 21:44:04 ...: [ 482.520462] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:44:04 ...: [ 482.520467] mdadm D 0000000000000000 0 2283 2212 0x00000000 21:44:04 ...: [ 482.520475] ffff88002cca7d98 0000000000000086 0000000000015bc0 0000000000015bc0 21:44:04 ...: [ 482.520483] ffff88002ededf78 ffff88002cca7fd8 0000000000015bc0 ffff88002ededbc0 21:44:04 ...: [ 482.520490] 0000000000015bc0 ffff88002cca7fd8 0000000000015bc0 ffff88002ededf78 21:44:04 ...: [ 482.520498] Call Trace: 21:44:04 ...: [ 482.520508] [<ffffffff81543a97>] __mutex_lock_slowpath+0xf7/0x180 21:44:04 ...: [ 482.520515] [<ffffffff8154397b>] mutex_lock+0x2b/0x50 21:44:04 ...: [ 482.520521] [<ffffffff8117404d>] __blkdev_put+0x3d/0x190 21:44:04 ...: [ 482.520527] [<ffffffff811741b0>] blkdev_put+0x10/0x20 21:44:04 ...: [ 482.520533] [<ffffffff811741f3>] blkdev_close+0x33/0x60 21:44:04 ...: [ 482.520541] [<ffffffff81145375>] __fput+0xf5/0x210 21:44:04 ...: [ 482.520547] [<ffffffff811454b5>] fput+0x25/0x30 21:44:04 ...: [ 482.520554] [<ffffffff811415ad>] filp_close+0x5d/0x90 21:44:04 ...: [ 482.520560] [<ffffffff81141697>] sys_close+0xb7/0x120 21:44:04 ...: [ 482.520568] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:44:04 ...: [ 482.520574] INFO: task md0_reshape:2287 blocked for more than 120 seconds. 21:44:04 ...: [ 482.520578] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:44:04 ...: [ 482.520582] md0_reshape D ffff88003aee96f0 0 2287 2 0x00000000 21:44:04 ...: [ 482.520590] ffff88003cf05a70 0000000000000046 0000000000015bc0 0000000000015bc0 21:44:04 ...: [ 482.520597] ffff88003aee9aa8 ffff88003cf05fd8 0000000000015bc0 ffff88003aee96f0 21:44:04 ...: [ 482.520605] 0000000000015bc0 ffff88003cf05fd8 0000000000015bc0 ffff88003aee9aa8 21:44:04 ...: [ 482.520612] Call Trace: 21:44:04 ...: [ 482.520623] [<ffffffffa0224892>] get_active_stripe+0x312/0x3f0 [raid456] 21:44:04 ...: [ 482.520633] [<ffffffff81059ae0>] ? default_wake_function+0x0/0x20 21:44:04 ...: [ 482.520643] [<ffffffffa0226f80>] reshape_request+0x4c0/0x9a0 [raid456] 21:44:04 ...: [ 482.520651] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:44:04 ...: [ 482.520661] [<ffffffffa022777a>] sync_request+0x31a/0x3a0 [raid456] 21:44:04 ...: [ 482.520668] [<ffffffff81052713>] ? __wake_up+0x53/0x70 21:44:04 ...: [ 482.520675] [<ffffffff814156b1>] md_do_sync+0x621/0xbb0 21:44:04 ...: [ 482.520685] [<ffffffff810387b9>] ? default_spin_lock_flags+0x9/0x10 21:44:04 ...: [ 482.520692] [<ffffffff8141640c>] md_thread+0x5c/0x130 21:44:04 ...: [ 482.520699] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:44:04 ...: [ 482.520705] [<ffffffff814163b0>] ? md_thread+0x0/0x130 21:44:04 ...: [ 482.520711] [<ffffffff81084416>] kthread+0x96/0xa0 21:44:04 ...: [ 482.520718] [<ffffffff810131ea>] child_rip+0xa/0x20 21:44:04 ...: [ 482.520725] [<ffffffff81084380>] ? kthread+0x0/0xa0 21:44:04 ...: [ 482.520730] [<ffffffff810131e0>] ? child_rip+0x0/0x20 21:44:04 ...: [ 482.520735] INFO: task mdadm:2288 blocked for more than 120 seconds. 21:44:04 ...: [ 482.520739] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:44:04 ...: [ 482.520743] mdadm D 0000000000000000 0 2288 1 0x00000000 21:44:04 ...: [ 482.520751] ffff88002cca9c18 0000000000000086 0000000000015bc0 0000000000015bc0 21:44:04 ...: [ 482.520759] ffff88003aee83b8 ffff88002cca9fd8 0000000000015bc0 ffff88003aee8000 21:44:04 ...: [ 482.520767] 0000000000015bc0 ffff88002cca9fd8 0000000000015bc0 ffff88003aee83b8 21:44:04 ...: [ 482.520774] Call Trace: 21:44:04 ...: [ 482.520782] [<ffffffff81543a97>] __mutex_lock_slowpath+0xf7/0x180 21:44:04 ...: [ 482.520790] [<ffffffff812a6d50>] ? exact_match+0x0/0x10 21:44:04 ...: [ 482.520797] [<ffffffff8154397b>] mutex_lock+0x2b/0x50 21:44:04 ...: [ 482.520804] [<ffffffff811742c8>] __blkdev_get+0x68/0x3d0 21:44:04 ...: [ 482.520810] [<ffffffff81174650>] ? blkdev_open+0x0/0xc0 21:44:04 ...: [ 482.520816] [<ffffffff81174640>] blkdev_get+0x10/0x20 21:44:04 ...: [ 482.520822] [<ffffffff811746c1>] blkdev_open+0x71/0xc0 21:44:04 ...: [ 482.520829] [<ffffffff811419f3>] __dentry_open+0x113/0x370 21:44:04 ...: [ 482.520837] [<ffffffff81253f8f>] ? security_inode_permission+0x1f/0x30 21:44:04 ...: [ 482.520843] [<ffffffff8114de3f>] ? inode_permission+0xaf/0xd0 21:44:04 ...: [ 482.520850] [<ffffffff81141d67>] nameidata_to_filp+0x57/0x70 21:44:04 ...: [ 482.520857] [<ffffffff8115207a>] do_filp_open+0x2da/0xba0 21:44:04 ...: [ 482.520864] [<ffffffff810ff0e1>] ? lru_cache_add_lru+0x21/0x40 21:44:04 ...: [ 482.520871] [<ffffffff8111109c>] ? do_anonymous_page+0x11c/0x330 21:44:04 ...: [ 482.520878] [<ffffffff81115d5f>] ? handle_mm_fault+0x31f/0x3c0 21:44:04 ...: [ 482.520885] [<ffffffff8115dbfa>] ? alloc_fd+0x10a/0x150 21:44:04 ...: [ 482.520891] [<ffffffff81141769>] do_sys_open+0x69/0x170 21:44:04 ...: [ 482.520897] [<ffffffff811418b0>] sys_open+0x20/0x30 21:44:04 ...: [ 482.520905] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:46:04 ...: [ 602.520053] INFO: task mdadm:1937 blocked for more than 120 seconds. 21:46:04 ...: [ 602.520059] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:46:04 ...: [ 602.520065] mdadm D 00000000ffffffff 0 1937 1 0x00000000 21:46:04 ...: [ 602.520075] ffff88002ef4f5d8 0000000000000082 0000000000015bc0 0000000000015bc0 21:46:04 ...: [ 602.520084] ffff88002eb5b198 ffff88002ef4ffd8 0000000000015bc0 ffff88002eb5ade0 21:46:04 ...: [ 602.520091] 0000000000015bc0 ffff88002ef4ffd8 0000000000015bc0 ffff88002eb5b198 21:46:04 ...: [ 602.520099] Call Trace: 21:46:04 ...: [ 602.520127] [<ffffffffa0224892>] get_active_stripe+0x312/0x3f0 [raid456] 21:46:04 ...: [ 602.520142] [<ffffffff81059ae0>] ? default_wake_function+0x0/0x20 21:46:04 ...: [ 602.520153] [<ffffffffa0228413>] make_request+0x243/0x4b0 [raid456] 21:46:04 ...: [ 602.520162] [<ffffffffa0221a90>] ? release_stripe+0x50/0x70 [raid456] 21:46:04 ...: [ 602.520171] [<ffffffff81084790>] ? autoremove_wake_function+0x0/0x40 21:46:04 ...: [ 602.520180] [<ffffffff81414df0>] md_make_request+0xc0/0x130 21:46:04 ...: [ 602.520187] [<ffffffff81414df0>] ? md_make_request+0xc0/0x130 21:46:04 ...: [ 602.520197] [<ffffffff8129f8c1>] generic_make_request+0x1b1/0x4f0 21:46:04 ...: [ 602.520206] [<ffffffff810f6515>] ? mempool_alloc_slab+0x15/0x20 21:46:04 ...: [ 602.520215] [<ffffffff8116c2ec>] ? alloc_buffer_head+0x1c/0x60 21:46:04 ...: [ 602.520222] [<ffffffff8129fc80>] submit_bio+0x80/0x110 21:46:04 ...: [ 602.520229] [<ffffffff8116c849>] submit_bh+0xf9/0x140 21:46:04 ...: [ 602.520237] [<ffffffff8116f124>] block_read_full_page+0x274/0x3b0 21:46:04 ...: [ 602.520244] [<ffffffff81172c90>] ? blkdev_get_block+0x0/0x70 21:46:04 ...: [ 602.520252] [<ffffffff8110d875>] ? __inc_zone_page_state+0x35/0x40 21:46:04 ...: [ 602.520259] [<ffffffff810f46d8>] ? add_to_page_cache_locked+0xe8/0x160 21:46:04 ...: [ 602.520266] [<ffffffff81173d78>] blkdev_readpage+0x18/0x20 21:46:04 ...: [ 602.520273] [<ffffffff810f484b>] __read_cache_page+0x7b/0xe0 21:46:04 ...: [ 602.520279] [<ffffffff81173d60>] ? blkdev_readpage+0x0/0x20 21:46:04 ...: [ 602.520285] [<ffffffff81173d60>] ? blkdev_readpage+0x0/0x20 21:46:04 ...: [ 602.520292] [<ffffffff810f57dc>] do_read_cache_page+0x3c/0x120 21:46:04 ...: [ 602.520300] [<ffffffff810f5909>] read_cache_page_async+0x19/0x20 21:46:04 ...: [ 602.520306] [<ffffffff810f591e>] read_cache_page+0xe/0x20 21:46:04 ...: [ 602.520314] [<ffffffff811a6cb0>] read_dev_sector+0x30/0xa0 21:46:04 ...: [ 602.520321] [<ffffffff811a7fcd>] amiga_partition+0x6d/0x460 21:46:04 ...: [ 602.520328] [<ffffffff811a7938>] check_partition+0x138/0x190 21:46:04 ...: [ 602.520335] [<ffffffff811a7a7a>] rescan_partitions+0xea/0x2f0 21:46:04 ...: [ 602.520342] [<ffffffff811744c7>] __blkdev_get+0x267/0x3d0 21:46:04 ...: [ 602.520348] [<ffffffff81174650>] ? blkdev_open+0x0/0xc0 21:46:04 ...: [ 602.520354] [<ffffffff81174640>] blkdev_get+0x10/0x20 21:46:04 ...: [ 602.520359] [<ffffffff811746c1>] blkdev_open+0x71/0xc0 21:46:04 ...: [ 602.520367] [<ffffffff811419f3>] __dentry_open+0x113/0x370 21:46:04 ...: [ 602.520375] [<ffffffff81253f8f>] ? security_inode_permission+0x1f/0x30 21:46:04 ...: [ 602.520383] [<ffffffff8114de3f>] ? inode_permission+0xaf/0xd0 21:46:04 ...: [ 602.520390] [<ffffffff81141d67>] nameidata_to_filp+0x57/0x70 21:46:04 ...: [ 602.520397] [<ffffffff8115207a>] do_filp_open+0x2da/0xba0 21:46:04 ...: [ 602.520404] [<ffffffff811134a8>] ? unmap_vmas+0x178/0x310 21:46:04 ...: [ 602.520413] [<ffffffff8115dbfa>] ? alloc_fd+0x10a/0x150 21:46:04 ...: [ 602.520419] [<ffffffff81141769>] do_sys_open+0x69/0x170 21:46:04 ...: [ 602.520425] [<ffffffff811418b0>] sys_open+0x20/0x30 21:46:04 ...: [ 602.520434] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b 21:46:04 ...: [ 602.520443] INFO: task mdadm:2283 blocked for more than 120 seconds. 21:46:04 ...: [ 602.520447] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 21:46:04 ...: [ 602.520451] mdadm D 0000000000000000 0 2283 2212 0x00000000 21:46:04 ...: [ 602.520460] ffff88002cca7d98 0000000000000086 0000000000015bc0 0000000000015bc0 21:46:04 ...: [ 602.520468] ffff88002ededf78 ffff88002cca7fd8 0000000000015bc0 ffff88002ededbc0 21:46:04 ...: [ 602.520475] 0000000000015bc0 ffff88002cca7fd8 0000000000015bc0 ffff88002ededf78 21:46:04 ...: [ 602.520483] Call Trace: 21:46:04 ...: [ 602.520492] [<ffffffff81543a97>] __mutex_lock_slowpath+0xf7/0x180 21:46:04 ...: [ 602.520500] [<ffffffff8154397b>] mutex_lock+0x2b/0x50 21:46:04 ...: [ 602.520506] [<ffffffff8117404d>] __blkdev_put+0x3d/0x190 21:46:04 ...: [ 602.520512] [<ffffffff811741b0>] blkdev_put+0x10/0x20 21:46:04 ...: [ 602.520518] [<ffffffff811741f3>] blkdev_close+0x33/0x60 21:46:04 ...: [ 602.520526] [<ffffffff81145375>] __fput+0xf5/0x210 21:46:04 ...: [ 602.520533] [<ffffffff811454b5>] fput+0x25/0x30 21:46:04 ...: [ 602.520539] [<ffffffff811415ad>] filp_close+0x5d/0x90 21:46:04 ...: [ 602.520545] [<ffffffff81141697>] sys_close+0xb7/0x120 21:46:04 ...: [ 602.520552] [<ffffffff810121b2>] system_call_fastpath+0x16/0x1b

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  • Firefox 3.5.6 causes entire computer to freeze

    - by Anthony Aziz
    Here's the situation: Environment: Just installed a fresh copy of Win7 Pro 32-bit to NTFS partition on 750GB SATA drive Hardware: E8400 3GHz ASUS P5QL Pro 4GB DDR2 1066 RAM EVGA 9800 GTX+ Plenty of cooling, no problems with hardware before Data is stored on a separate partition, including My Documents No security software is yet installed No extensions installed yet Problem: While using Firefox, sometimes the entire computer will freeze/hang. I get no mouse or keyboard input, can't CTRL+ALT+DEL, no "not responding" indication, just a static image on my display. My drivers are all up to date as far as I'm aware (I just installed this copy of Windows last week). I first noticed this when trying to install Xmarks. I went to the Xmarks site and tried to install and it would freeze. I managed to get it installed (Safe mode and the Mozilla addon site worked), but when I go to configure it (log in, etc), the computer freezes. I don't think it's a matter of usage time or memory issues, because while testing, I browsed wallpaper galleries for about 30 minutes, sometimes as many as 12-15 tabs open at a time, without issue. Sometimes I won't even try to install Xmarks at it will hang. I can install (some) other extensions, the only one I've tried is download status bar (which works). What I've done to try to fix: Restarted (duh) Windows safe mode Completely remove Firefox and install it to a new directory, according to Mozilla's KB (I haven't tried the profile manager, though I assume this does the same thing, except perhaps more thoroughly) Some BIOS changes, including Power options, disabling oveclocking (it was a modest overclock on the CPU, which has run Win7 beta and RC for almost a year now) Memtest Used another Windows user profile, same tragic results I'm STUCK now, with no idea what to do. I'm using Chrome as my main browser at the moment, but that's not something I want to be stuck with. I like Firefox and want to use it. I'm going to try creating a new profile first. One thing I did notice: I started leaving task manager and performance monitor open when anticipating (but dreading) a freeze. firefox.exe had low CPU and low memory, but it looked like overall disk usage was seeing some spikes on the small graph Performance Monitor gives you. I saw on one blog post a fellow using XP moved his Local Settings directory from a separate drive to his main drive, and that solved it, but I don't think my AppData directory is on my D: drive, and that's on the same physical device anyways. Still, something that might be worth trying. I'd extremely appreciate any help. Thanks very much. I really don't want to reinstall Windows from scratch again :( Anthony Aziz

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  • Generating moderately interesting images

    - by Williham Totland
    Abstract: Can you propose a mathematical-ish algorithm over a plane of pixels that will generate a moderately interesting image, preferably one that on the whole resembles something? The story thus far: Once upon a time I decided in an effort to reduce cycle waste on my (admittedly too) numerous computers, and set out to generate images in a moderately interesting fashion; using a PRNG and some clever math to create images that would, on the whole, resemble something. Or at least, that was the plan. As it turns out, clever math requires being a clever mathematician; this I am not. At some length I arrived at a method that preferred straight lines (as these are generally the components of which our world is made), perhaps too strongly. The result is mildly interesting; resembling, perhaps, city grids as such: Now for the question proper: Given the source code of this little program; can you improve upon it and propose a method that gives somewhat more interesting results? (e.g. not city grids, but perhaps faces, animals, geography, what have you) This is also meant as a sort of challenge; I suppose and as such I've set down some completely arbitrary and equally optional rules: The comments in the code says it all really. Suggestions and "solutions" should edit the algorithm itself, not the surrounding framework, except as for to fix errors that prevents the sample from compiling. The code should compile cleanly with a standard issue C compiler. (If the example provided doesn't, oops! Tell me, and I'll fix. :) The method should, though again, this is optional, not need to elicit help from your friendly neighborhood math library. Solutions should probably be deliverable by simply yanking out whatever is between the snip lines (the ones that say you should not edit above and below, respectively), with a statement to the effect of what you need to add to the preamble in particular. The code requires a C compiler and libpng to build; I'm not entirely confident that the MinGW compiler provides the necessities, but I would be surprised if it didn't. For Debian you'll want the libpng-dev package, and for Mac OS X you'll want the XCode tools.. The source code can be downloaded here. Warning: Massive code splurge incoming! // compile with gcc -o imggen -lpng imggen.c // optionally with -DITERATIONS=x, where x is an appropriate integer // If you're on a Mac or using MinGW, you may have to fiddle with the linker flags to find the library and includes. #include <stdio.h> #include <stdlib.h> #include <png.h> #ifdef ITERATIONS #define REPEAT #endif // ITERATIONS // YOU MAY CHANGE THE FOLLOWING DEFINES #define WIDTH 320 #define HEIGHT 240 // YOU MAY REPLACE THE FOLLOWING DEFINES AS APPROPRIATE #define INK 16384 void writePNG (png_bytepp imageBuffer, png_uint_32 width, png_uint_32 height, int iteration) { char *fname; asprintf(&fname, "out.%d.png", iteration); FILE *fp = fopen(fname, "wb"); if (!fp) return; png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); png_infop info_ptr = png_create_info_struct(png_ptr); png_init_io(png_ptr, fp); png_set_filter(png_ptr, PNG_FILTER_TYPE_DEFAULT, PNG_FILTER_NONE); png_set_compression_level(png_ptr, Z_BEST_COMPRESSION); png_set_IHDR(png_ptr, info_ptr, width, height, 8, PNG_COLOR_TYPE_GRAY, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); png_set_rows(png_ptr, info_ptr, imageBuffer); png_set_invert_mono(png_ptr); /// YOU MAY COMMENT OUT THIS LINE png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL); png_destroy_write_struct(&png_ptr, &info_ptr); fclose(fp); free(fname); } int main (int argc, const char * argv[]) { png_uint_32 height = HEIGHT, width = WIDTH; int iteration = 1; #ifdef REPEAT for (iteration = 1; iteration <= ITERATIONS; iteration++) { #endif // REPEAT png_bytepp imageBuffer = malloc(sizeof(png_bytep) * height); for (png_uint_32 i = 0; i < height; i++) { imageBuffer[i] = malloc(sizeof(png_byte) * width); for (png_uint_32 j = 0; j < width; j++) { imageBuffer[i][j] = 0; } } /// CUT ACROSS THE DASHED LINES /// ------------------------------------------- /// NO EDITING ABOVE THIS LINE; EXCEPT AS NOTED int ink = INK; int x = rand() % width, y = rand() % height; int xdir = (rand() % 2)?1:-1; int ydir = (rand() % 2)?1:-1; while (ink) { imageBuffer[y][x] = 255; --ink; xdir += (rand() % 2)?(1):(-1); ydir += (rand() % 2)?(1):(-1); if (ydir > 0) { ++y; } else if (ydir < 0) { --y; } if (xdir > 0) { ++x; } else if (xdir < 0) { --x; } if (x == -1 || y == -1 || x == width || y == height || x == y && x == 0) { x = rand() % width; y = rand() % height; xdir = (rand() % 2)?1:-1; ydir = (rand() % 2)?1:-1; } } /// NO EDITING BELOW THIS LINE /// ------------------------------------------- writePNG(imageBuffer, width, height, iteration); for (png_uint_32 i = 0; i < height; i++) { free(imageBuffer[i]); } free(imageBuffer); #ifdef REPEAT } #endif // REPEAT return 0; } Note: While this question doesn't strictly speaking seem "answerable" as such; I still believe that it can give rise to some manner of "right" answer. Maybe. Happy hunting.

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  • Confusing Java syntax...

    - by posfan12
    I'm trying to convert the following code (from Wikipedia) from Java to JavaScript: /* * 3 June 2003, [[:en:User:Cyp]]: * Maze, generated by my algorithm * 24 October 2006, [[:en:User:quin]]: * Source edited for clarity * 25 January 2009, [[:en:User:DebateG]]: * Source edited again for clarity and reusability * 1 June 2009, [[:en:User:Nandhp]]: * Source edited to produce SVG file when run from the command-line * * This program was originally written by [[:en:User:Cyp]], who * attached it to the image description page for an image generated by * it on en.wikipedia. The image was licensed under CC-BY-SA-3.0/GFDL. */ import java.awt.*; import java.applet.*; import java.util.Random; /* Define the bit masks */ class Constants { public static final int WALL_ABOVE = 1; public static final int WALL_BELOW = 2; public static final int WALL_LEFT = 4; public static final int WALL_RIGHT = 8; public static final int QUEUED = 16; public static final int IN_MAZE = 32; } public class Maze extends java.applet.Applet { /* The width and height (in cells) of the maze */ private int width; private int height; private int maze[][]; private static final Random rnd = new Random(); /* The width in pixels of each cell */ private int cell_width; /* Construct a Maze with the default width, height, and cell_width */ public Maze() { this(20,20,10); } /* Construct a Maze with specified width, height, and cell_width */ public Maze(int width, int height, int cell_width) { this.width = width; this.height = height; this.cell_width = cell_width; } /* Initialization method that will be called when the program is * run from the command-line. Maze will be written as SVG file. */ public static void main(String[] args) { Maze m = new Maze(); m.createMaze(); m.printSVG(); } /* Initialization method that will be called when the program is * run as an applet. Maze will be displayed on-screen. */ public void init() { createMaze(); } /* The maze generation algorithm. */ private void createMaze(){ int x, y, n, d; int dx[] = { 0, 0, -1, 1 }; int dy[] = { -1, 1, 0, 0 }; int todo[] = new int[height * width], todonum = 0; /* We want to create a maze on a grid. */ maze = new int[width][height]; /* We start with a grid full of walls. */ for (x = 0; x < width; ++x) { for (y = 0; y < height; ++y) { if (x == 0 || x == width - 1 || y == 0 || y == height - 1) { maze[x][y] = Constants.IN_MAZE; } else { maze[x][y] = 63; } } } /* Select any square of the grid, to start with. */ x = 1 + rnd.nextInt (width - 2); y = 1 + rnd.nextInt (height - 2); /* Mark this square as connected to the maze. */ maze[x][y] &= ~48; /* Remember the surrounding squares, as we will */ for (d = 0; d < 4; ++d) { if ((maze[][d][][d] & Constants.QUEUED) != 0) { /* want to connect them to the maze. */ todo[todonum++] = ((x + dx[d]) << Constants.QUEUED) | (y + dy[d]); maze[][d][][d] &= ~Constants.QUEUED; } } /* We won't be finished until all is connected. */ while (todonum > 0) { /* We select one of the squares next to the maze. */ n = rnd.nextInt (todonum); x = todo[n] >> 16; /* the top 2 bytes of the data */ y = todo[n] & 65535; /* the bottom 2 bytes of the data */ /* We will connect it, so remove it from the queue. */ todo[n] = todo[--todonum]; /* Select a direction, which leads to the maze. */ do { d = rnd.nextInt (4); } while ((maze[][d][][d] & Constants.IN_MAZE) != 0); /* Connect this square to the maze. */ maze[x][y] &= ~((1 << d) | Constants.IN_MAZE); maze[][d][][d] &= ~(1 << (d ^ 1)); /* Remember the surrounding squares, which aren't */ for (d = 0; d < 4; ++d) { if ((maze[][d][][d] & Constants.QUEUED) != 0) { /* connected to the maze, and aren't yet queued to be. */ todo[todonum++] = ((x + dx[d]) << Constants.QUEUED) | (y + dy[d]); maze[][d][][d] &= ~Constants.QUEUED; } } /* Repeat until finished. */ } /* Add an entrance and exit. */ maze[1][1] &= ~Constants.WALL_ABOVE; maze[width - 2][height - 2] &= ~Constants.WALL_BELOW; } /* Called by the applet infrastructure to display the maze on-screen. */ public void paint(Graphics g) { drawMaze(g); } /* Called to write the maze to an SVG file. */ public void printSVG() { System.out.format("<svg width=\"%d\" height=\"%d\" version=\"1.1\"" + " xmlns=\"http://www.w3.org/2000/svg\">\n", width*cell_width, height*cell_width); System.out.println(" <g stroke=\"black\" stroke-width=\"1\"" + " stroke-linecap=\"round\">"); drawMaze(null); System.out.println(" </g>\n</svg>"); } /* Main maze-drawing loop. */ public void drawMaze(Graphics g) { int x, y; for (x = 1; x < width - 1; ++x) { for (y = 1; y < height - 1; ++y) { if ((maze[x][y] & Constants.WALL_ABOVE) != 0) drawLine( x * cell_width, y * cell_width, (x + 1) * cell_width, y * cell_width, g); if ((maze[x][y] & Constants.WALL_BELOW) != 0) drawLine( x * cell_width, (y + 1) * cell_width, (x + 1) * cell_width, (y + 1) * cell_width, g); if ((maze[x][y] & Constants.WALL_LEFT) != 0) drawLine( x * cell_width, y * cell_width, x * cell_width, (y + 1) * cell_width, g); if ((maze[x][y] & Constants.WALL_RIGHT) != 0) drawLine((x + 1) * cell_width, y * cell_width, (x + 1) * cell_width, (y + 1) * cell_width, g); } } } /* Draw a line, either in the SVG file or on the screen. */ public void drawLine(int x1, int y1, int x2, int y2, Graphics g) { if ( g != null ) g.drawLine(x1, y1, x2, y2); else System.out.format(" <line x1=\"%d\" y1=\"%d\"" + " x2=\"%d\" y2=\"%d\" />\n", x1, y1, x2, y2); } } Anyway, I was chugging along fairly quickly when I came to a bit that I just don't understand: /* Remember the surrounding squares, as we will */ for (var d = 0; d < 4; ++d) { if ((maze[][d][][d] & Constants.QUEUED) != 0) { /* want to connect them to the maze. */ todo[todonum++] = ((x + dx[d]) << Constants.QUEUED) | (y + dy[d]); maze[][d][][d] &= ~Constants.QUEUED; } } What I don't get is why there are four sets of brackets following the "maze" parameter instead of just two, since "maze" is a two dimensional array, not a four dimensional array. I'm sure there's a good reason for this. Problem is, I just don't get it. Thanks!

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  • C++ assignment operators dynamic arrays

    - by user2905445
    First off i know the multiplying part is wrong but i have some questions about the code. 1. When i am overloading my operator+ i print out the matrix using cout << *this then right after i return *this and when i do a+b on matix a and matix b it doesnt give me the same thing this is very confusing. 2. When i make matrix c down in my main i cant use my default constructor for some reason because when i go to set it = using my assignment operator overloaded function it gives me an error saying "expression must be a modifiable value. although using my constructor that sets the row and column numbers is the same as my default constructor using (0,0). 3. My assignment operator= function uses a copy constructor to make a new matrix using the values on the right hand side of the equal sign and when i print out c it doesn't give me anything Any help would be great this is my hw for a algorithm class which i still need to do the algorithm for the multiplying matrices but i need to solve these issues first and im having a lot of trouble please help. //Programmer: Eric Oudin //Date: 10/21/2013 //Description: Working with matricies #include <iostream> using namespace std; class matrixType { public: friend ostream& operator<<(ostream&, const matrixType&); const matrixType& operator*(const matrixType&); matrixType& operator+(const matrixType&); matrixType& operator-(const matrixType&); const matrixType& operator=(const matrixType&); void fillMatrix(); matrixType(); matrixType(int, int); matrixType(const matrixType&); ~matrixType(); private: int **matrix; int rowSize; int columnSize; }; ostream& operator<< (ostream& osObject, const matrixType& matrix) { osObject << endl; for (int i=0;i<matrix.rowSize;i++) { for (int j=0;j<matrix.columnSize;j++) { osObject << matrix.matrix[i][j] <<", "; } osObject << endl; } return osObject; } const matrixType& matrixType::operator=(const matrixType& matrixRight) { matrixType temp(matrixRight); cout << temp; return temp; } const matrixType& matrixType::operator*(const matrixType& matrixRight) { matrixType temp(rowSize*matrixRight.columnSize, columnSize*matrixRight.rowSize); if(rowSize == matrixRight.columnSize) { for (int i=0;i<rowSize;i++) { for (int j=0;j<columnSize;j++) { temp.matrix[i][j] = matrix[i][j] * matrixRight.matrix[i][j]; } } } else { cout << "Cannot multiply matricies that have different size rows from the others columns." << endl; } return temp; } matrixType& matrixType::operator+(const matrixType& matrixRight) { if(rowSize == matrixRight.rowSize && columnSize == matrixRight.columnSize) { for (int i=0;i<rowSize;i++) { for (int j=0;j<columnSize;j++) { matrix[i][j] += matrixRight.matrix[i][j]; } } } else { cout << "Cannot add matricies that are different sizes." << endl; } cout << *this; return *this; } matrixType& matrixType::operator-(const matrixType& matrixRight) { matrixType temp(rowSize, columnSize); if(rowSize == matrixRight.rowSize && columnSize == matrixRight.columnSize) { for (int i=0;i<rowSize;i++) { for (int j=0;j<columnSize;j++) { matrix[i][j] -= matrixRight.matrix[i][j]; } } } else { cout << "Cannot subtract matricies that are different sizes." << endl; } return *this; } void matrixType::fillMatrix() { for (int i=0;i<rowSize;i++) { for (int j=0;j<columnSize;j++) { cout << "Enter the matix number at (" << i << "," << j << "):"; cin >> matrix[i][j]; } } } matrixType::matrixType() { rowSize=0; columnSize=0; matrix = new int*[rowSize]; for (int i=0; i < rowSize; i++) { matrix[i] = new int[columnSize]; } } matrixType::matrixType(int setRows, int setColumns) { rowSize=setRows; columnSize=setColumns; matrix = new int*[rowSize]; for (int i=0; i < rowSize; i++) { matrix[i] = new int[columnSize]; } } matrixType::matrixType(const matrixType& otherMatrix) { rowSize=otherMatrix.rowSize; columnSize=otherMatrix.columnSize; matrix = new int*[rowSize]; for (int i = 0; i < rowSize; i++) { for (int j = 0; j < columnSize; j++) { matrix[i]=new int[columnSize]; matrix[i][j]=otherMatrix.matrix[i][j]; } } } matrixType::~matrixType() { delete [] matrix; } int main() { matrixType a(2,2); matrixType b(2,2); matrixType c(0,0); cout << "fill matrix a:"<< endl;; a.fillMatrix(); cout << "fill matrix b:"<< endl;; b.fillMatrix(); cout << a; cout << b; c = a+b; cout <<"matrix a + matrix b =" << c; system("PAUSE"); return 0; }

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  • Will these optimizations to my Ruby implementation of diff improve performance in a Rails app?

    - by grg-n-sox
    <tl;dr> In source version control diff patch generation, would it be worth it to use the optimizations listed at the very bottom of this writing (see <optimizations>) in my Ruby implementation of diff for making diff patches? </tl;dr> <introduction> I am programming something I have never done before and there might already be tools out there to do the exact thing I am programming but at this point I am having too much fun to care so I am still going to do it from scratch, even if there is a tool for this. So anyways, I am working on a Ruby on Rails app and need a certain feature. Basically I want each entry in a table of mine, let's say for example a table of video games, to have a stored chunk of text that represents a review or something of the sort for that table entry. However, I want this text to be both editable by any registered user and also keep track of different submissions in a version control system. The simplest solution I could think of is just implement a solution that keeps track of the text body and the diff patch history of different versions of the text body as objects in Ruby and then serialize it, preferably in human readable form (so I'll most likely use YAML for this) for editing if needed due to corruption by a software bug or a mistake is made by an admin doing some version editing. So at first I just tried to dive in head first into this feature to find that the problem of generating a diff patch is more difficult that I thought to do efficiently. So I did some research and came across some ideas. Some I have implemented already and some I have not. However, it all pretty much revolves around the longest common subsequence problem, as you would already know if you have already done anything with diff or diff-like features, and optimization the function that solves it. Currently I have it so it truncates the compared versions of the text body from the beginning and end until non-matching lines are found. Then it solves the problem using a comparison matrix, but instead of incrementing the value stored in a cell when it finds a matching line like in most longest common subsequence algorithms I have seen examples of, I increment when I have a non-matching line so as to calculate edit distance instead of longest common subsequence. Although as far as I can tell between the two approaches, they are essentially two sides of the same coin so either could be used to derive an answer. It then back-traces through the comparison matrix and notes when there was an incrementation and in which adjacent cell (West, Northwest, or North) to determine that line's diff entry and assumes all other lines to be unchanged. Normally I would leave it at that, but since this is going into a Rails environment and not just some stand-alone Ruby script, I started getting worried about needing to optimize at least enough so if a spammer that somehow knew how I implemented the version control system and knew my worst case scenario entry still wouldn't be able to hit the server that bad. After some searching and reading of research papers and articles through the internet, I've come across several that seem decent but all seem to have pros and cons and I am having a hard time deciding how well in this situation that the pros and cons balance out. So are the ones listed here worth it? I have listed them with known pros and cons. </introduction> <optimizations> Chop the compared sequences into multiple chucks of subsequences by splitting where lines are unchanged, and then truncating each section of unchanged lines at the beginning and end of each section. Then solve the edit distance of each subsequence. Pro: Changes the time increase as the changed area gets bigger from a quadratic increase to something more similar to a linear increase. Con: Figuring out where to split already seems like you have to solve edit distance except now you don't care how it is changed. Would be fine if this was solvable by a process closer to solving hamming distance but a single insertion would throw this off. Use a cryptographic hash function to both convert all sequence elements into integers and ensure uniqueness. Then solve the edit distance comparing the hash integers instead of the sequence elements themselves. Pro: The operation of comparing two integers is faster than the operation of comparing two strings, so a slight performance gain is received after every comparison, which can be a lot overall. Con: Using a cryptographic hash function takes time to convert all the sequence elements and may end up costing more time to do the conversion that you gain back from the integer comparisons. You could use the built in hash function for a string but that will not guarantee uniqueness. Use lazy evaluation to only calculate the three center-most diagonals of the comparison matrix and then only calculate additional diagonals as needed. And then also use this approach to possibly remove the need on some comparisons to compare all three adjacent cells as desribed here. Pro: Can turn an algorithm that always takes O(n * m) time and make it so only worst case scenario is that time, best case becomes practically linear, and average case is somewhere between the two. Con: It is an algorithm I've only seen implemented in functional programming languages and I am having a difficult time comprehending how to convert this into Ruby based on how it is described at the site linked to above. Make a C module and do the hard work at the native level in C and just make a Ruby wrapper for it so Ruby can make all the calls to it that it needs. Pro: I have to imagine that evaluating something like this in could be a LOT faster. Con: I have no idea how Rails handles apps with ruby code that has C extensions and it hurts the portability of the app. This is an optimization for after the solving of edit distance, but idea is to store additional combined diffs with the ones produced by each version to make a delta-tree data structure with the most recently made diff as the root node of the tree so getting to any version takes worst case time of O(log n) instead of O(n). Pro: Would make going back to an old version a lot faster. Con: It would mean every new commit, the delta-tree would get a new root node that will cost time to reorganize the delta-tree for an operation that will be carried out a lot more often than going back a version, not to mention the unlikelihood it will be an old version. </optimizations> So are these things worth the effort?

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  • Monitoring tools that can take high rate and high volume?

    - by Jon Watte
    We're using Cacti with RRDTool to monitor and graph about 100,000 counters spread across about 1,000 Linux-based nodes. However, our current setup generally only gives us 5-minute graphs (with some data being minute-based); we often make changes where seeing feedback in "near real time" would be of value. I'd like approximately a week of 5- or 10-second data, a year of 1-minute data, and 5 years of 10-minute data. I have SSD disks and a dual-hexa-core server to spare. I tried setting up a Graphite/carbon/whisper server, and had about 15 nodes pipe to it, but it only has "average" for the retention function when promoting to older buckets. This is almost useless -- I'd like min, max, average, standard deviation, and perhaps "total sum" and "number of samples" or perhaps "95th percentile" available. The developer claims there's a new back-end "in beta" that allows you to write your own function, but this appears to still only do 1:1 retention (when saving older data, you really want the statistics calculated into many streams from a single input. Also, "in beta" seems a little risky for this installation. If I'm wrong about this assumption, I'd be happy to be shown my error! I've heard Zabbix recommended, but it puts data into MySQL or some other SQL database. 100,000 counters on a 5 second interval means 20,000 tps, and while I have an SSD, I don't have an 8-way RAID-6 with battery backup cache, which I think I'd need for that to work out :-) Again, if that's actually something that's not a problem, I'd be happy to be shown the error of my ways. Also, can Zabbix do the single data stream - promote with statistics thing? Finally, Munin claims to have a new 2.0 coming out "in beta" right now, and it boasts custom retention plans. However, again, it's that "in beta" part -- has anyone used that for real, and at scale? How did it perform, if so? I'm almost thinking about using a graphing front-end (such as Graphite) and rolling my own retention backend with a simple layer on top of mmap() and some stats. That wouldn't be particularly hard, and would probably perform very well, letting the kernel figure out the balance between frequency of flushing to disk and process operations. Any other suggestions I should look into? Note: it has to have shown itself able to sustain the kinds of data loads I'm suggesting above; if you can point at the specific implementation you're referencing, so much the better!

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  • APC PHP cache size does not exceed 32MB, even though settings allow for more

    - by hardy101
    I am setting up APC (v 3.1.9) on a high-traffic WordPress installation on CentOS 6.0 64 bit. I have figured out many of the quirks with APC, but something is still not quite right. No matter what settings I change, APC never actually caches more than 32MB. I'm trying to bump it up to 256 MB. 32MB is a default amount for apc.shm_size, so I am wondering if it's stuck there somehow. I have run the following echo '2147483648' > /proc/sys/kernel/shmmax to increase my system's shared memory to 2G (half of my 4G box). Then ran ipcs -lm which returns ------ Shared Memory Limits -------- max number of segments = 4096 max seg size (kbytes) = 2097152 max total shared memory (kbytes) = 8388608 min seg size (bytes) = 1 Also made a change in /etc/sysctl.conf then ran sysctl -p to make the settings stick on the server. Rebooted, too, for good measure. In my APC settings, I have mmap enabled (which happens by default in recent versions of APC). php.ini looks like: apc.stat=0 apc.shm_size="256M" apc.max_file_size="10M" apc.mmap_file_mask="/tmp/apc.XXXXXX" apc.ttl="7200" I am aware that mmap mode will ignore references to apc.shm_segments, so I have left it out with default 1. phpinfo() indicates the following about APC: Version 3.1.9 APC Debugging Disabled MMAP Support Enabled MMAP File Mask /tmp/apc.bPS7rB Locking type pthread mutex Locks Serialization Support php Revision $Revision: 308812 $ Build Date Oct 11 2011 22:55:02 Directive Local Value apc.cache_by_default On apc.canonicalize O apc.coredump_unmap Off apc.enable_cli Off apc.enabled On On apc.file_md5 Off apc.file_update_protection 2 apc.filters no value apc.gc_ttl 3600 apc.include_once_override Off apc.lazy_classes Off apc.lazy_functions Off apc.max_file_size 10M apc.mmap_file_mask /tmp/apc.bPS7rB apc.num_files_hint 1000 apc.preload_path no value apc.report_autofilter Off apc.rfc1867 Off apc.rfc1867_freq 0 apc.rfc1867_name APC_UPLOAD_PROGRESS apc.rfc1867_prefix upload_ apc.rfc1867_ttl 3600 apc.serializer default apc.shm_segments 1 apc.shm_size 256M apc.slam_defense On apc.stat Off apc.stat_ctime Off apc.ttl 7200 apc.use_request_time On apc.user_entries_hint 4096 apc.user_ttl 0 apc.write_lock On apc.php reveals the following graph, no matter how long the server runs (cache size fluctuates and hovers at just under 32MB. See image http://i.stack.imgur.com/2bwMa.png You can see that the cache is trying to allocate 256MB, but the brown piece of the pie keeps getting recycled at 32MB. This is confirmed as refreshing the apc.php page shows cached file counts that move up and down (implying that the cache is not holding onto all of its files). Does anyone have an idea of how to get APC to use more than 32 MB for its cache size?? **Note that the identical behavior occurs for eaccelerator, xcache, and APC. I read here: http://www.litespeedtech.com/support/forum/archive/index.php/t-5072.html that suEXEC could cause this problem.

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  • My VPS ubuntu server is very slow

    - by askmike
    I just installed a frech copy of Ubuntu 12.04 on my vps because my old installation was very slow, unfortunately this did not fix the problem. With slow I mean requests for my PHP websites take a long time, very slow (30 sec per request) to slow (3+ sec per request). When it's really bad SSH is also laggish. The websites are: askmike.org (pretty standard Wordpress) mvr.me (own PHP) slow? very slow: Here is a picture of loading a clean install of wordpress slow: here is a picture of loading a small PHP based website the vps The VPS has 256mb ram and an 25GB hdd. Besides serving the 2 small websites it isn't doing anything AFAIK. What have I installed Clean Ubuntu server 12.04 LAMP stack few things like git and nodejs (not using both) ossec (because I thought my server was getting hammered) munin What I already tried / done I installed munin so that I could watch io speed and such. The problem is that I don't know where to look for in the munin report. I checked logs and don't see anything strange (although I don't really know where to look for besides strange / repetitive errors and GET requests). I configured Apache MPM to: <IfModule mpm_prefork_module> StartServers 5 MinSpareServers 5 MaxSpareServers 10 MaxClients 40 MaxRequestsPerChild 0 </IfModule> (apache is using prefork, the default) Stats I copied the munin report as it appeared at 4:50 last night to a site hosted on a shared webhost. Note that tonight my mysql crashed somewhere after 1:00 (which is a new problem altogether), so therefor the graph for last night might look strange. Can anyone help me get my VPS up to normal speed? EDIT: Thanks for the replies. The VPS is 10 bucks a month and is from directvps.nl (Dutch host and I'm also dutch). I did two speed tests for disk IO: $ dd if=/dev/zero of=test bs=64k count=16k conv=fdatasync 1073741824 bytes (1.1 GB) copied, 23.1506 s, 46.4 MB/s $ dd if=/dev/zero of=test bs=64k count=16k conv=fdatasync 1073741824 bytes (1.1 GB) copied, 39.3796 s, 27.3 MB/s Anyway: how can I prove to my VPS host that it is to slow? I can understand a server being busy slowing a website down. But 5-30 sec loadtime for a normal PHP webpage?

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  • Help Me Make My Pascal Program Display Multiple Names Which Were Entered Plz.

    - by Sketchie
    Hey,Guys I'm having trouble displaying names using arrays in my Pascal program. But first heres the question I'm writing the program to answer : Develop pseudocode that accepts as input the name of an unspecified number of masqueraders who each have paid the full cost of their costume and the amount each has paid. A masquerader may have paid for a costume in any of the five sections in the band. The algorithm should determine the section in which the masquerader plays, based on the amount he/she has paid for the costume. The algorithm should also determine the number of masqueraders who have paid for costumes in each section. The names of persons and the section for which they have paid should be printed. A listing of the sections and the total number of persons registered to play in each section should also be printed, along with the total amount paid in each section. And here's what I've done so far(It's a bit messy): program Maqueprgrm; uses wincrt; type names=array [1..30]of string; var name:string; s1_nms:names; s2_nms:names; s3_nms:names; s4_nms:names; s5_nms:names; amt_paid:integer; stop,x,full,ins,ttl1,ttl2,ttl3,ttl4,ttl5,sec_1,sec_2,sec_3,sec_4,sec_5,sec:integer; begin stop := 0; writeln ('To Begin Data Collecting Section Press 1, To End Press 0'); readln(stop); while stop <0 do begin for x:= 1 to 30 do x:= x+1; writeln ('Please Enter The Name of Masquerader.'); readln (name); writeln ('Please Enter The Amount Paid For Costume.'); readln (amt_paid); IF amt_paid = 144 THEN Begin full:=full+1; {people who paid in full + 1} sec_1:=sec_1+1; {people in this section + 1} ttl1:= ttl1+amt_paid; {total money earned in this section + amount person paid} s1_nms[x]:= name; {People's names in this section plus current entry's name} End else IF amt_paid = 184 then Begin ins:=ins+1; sec_1:=sec_1+1; ttl1:=ttl1+amt_paid; s1_nms[x]:= name; end else IF amt_paid = 198 then Begin full:=full+1; sec_2:=sec_2+1; ttl2:=ttl2+amt_paid; s2_nms[x]:= 'name'; end else IF amt_paid = 153 then Begin ins:=ins+1; sec_2:=sec_2+1; ttl2:=ttl2+amt_paid; s2_nms[x]:= 'name'; end else IF amt_paid = 264 then Begin full:=full+1; sec_3:=sec_3+1; ttl3:=ttl3+amt_paid; s3_nms[x]:= 'name'; end else IF amt_paid = 322 then Begin ins:=ins+1; sec_3:=sec_3+1; ttl3:=ttl3+amt_paid; s3_nms[x]:= 'name'; end else IF amt_paid = 315 then Begin full:=full+1; sec_4:=sec_4+1; ttl4:=ttl4+amt_paid; s4_nms[x]:= 'name'; end else IF amt_paid = 402 then Begin ins:=ins+1; sec_4:=sec_4+1; ttl4:=ttl4+amt_paid; s4_nms[x]:= 'name'; end else IF amt_paid = 382. then Begin ins:=ins+1; sec_4:=sec_4+1; ttl4:=ttl4+amt_paid; s4_nms[x]:= 'name'; end else IF amt_paid = 488 then Begin ins:=ins+1; sec_5:=sec_5+1; ttl5:=ttl5+amt_paid; s5_nms[x]:= 'name'; end else begin Writeln ('Invalid Entry'); For x:= 1 to 30 do end; writeln (' To Enter More Data Press 1, To Print Data and Calculations Press 0'); Readln (stop); End; writeln ('For Information on Sections Press 1, 2, 3, 4, or 5 Respectively'); Readln (sec); IF Sec= 1 THEN Begin for x:= 1 to 30 do; begin writeln ('The Number of Revelers in This Section is ',Sec_1,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins ,'.'); Writeln ('The Names of Revelers in This Section is ', S1_Nms[x], '.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl1, '.'); End; end else IF Sec= 2 THEN Begin For x:= 1 to 30 do begin Writeln ('The Number of Revelers in This Section is ', Sec_2,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins ,'.'); Writeln ('The Names of Revelers in This Section is ', S2_Nms[x] ,'.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl2, '.'); End; End else IF Sec= 3 THEN Begin For x:= 1 to 30 do begin writeln ('The Number of Revelers in This Section is ', Sec_3,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins ,'.'); Writeln ('The Names of Revelers in This Section is ', S3_Nms[x] ,'.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl3, '.'); End; End else IF Sec= 4 THEN Begin For x:= 1 to 30 do begin writeln ('The Number of Revelers in This Section is ', Sec_4,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins, '.'); Writeln ('The Names of Revelers in This Section is ', S4_Nms [x],'.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl4 ,'.'); End; End else IF Sec= 5 THEN Begin For x:= 1 to 30 do begin writeln ('The Number of Revelers in This Section is ', Sec_5,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins, '.'); Writeln ('The Names of Revelers in This Section is ', S5_Nms[x], '.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl5 ,'.'); End; End else BEGIN Writeln ('Invalid Entry. For Information on Sections Press 1, 2, 3, 4, or 5 Respectively. '); End; end. The result I keep getting is that for the names in the section it is only the name of the last person entered that is displayed. For example it would display: The number of revelers in this section is 2 The number of revelers in the band who paid in full is 2 {Band is the whole thing divided into 5 section} The number of revelers in the band who paid in installments is 0 The names of revelers in this section is Amy Total amount collected by this section is 288 So yea, the program only displays "Amy" even though I entered more than 1 name. Do you guys know how to fix it also if it's not asking too much could you help me to make a while loop for the last portion of the program so that after the user sees the info for a section he can see another section. It sucks that I've been working on it for a while but if it doesn't run properly tomorrow I'll fail. Help would be greatly appreciated and responses are welcome anytime cause i'll be up anyway. P.S. Sorry for the long post.

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  • March 21st Links: ASP.NET, ASP.NET MVC, AJAX, Visual Studio, Silverlight

    - by ScottGu
    Here is the latest in my link-listing series. If you haven’t already, check out this month’s "Find a Hoster” page on the www.asp.net website to learn about great (and very inexpensive) ASP.NET hosting offers.  [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] ASP.NET URL Routing in ASP.NET 4: Scott Mitchell has a nice article that talks about the new URL routing features coming to Web Forms applications with ASP.NET 4.  Also check out my previous blog post on this topic. Control of Web Control ClientID Values in ASP.NET 4: Scott Mitchell has a nice article that describes how it is now easy to control the client “id” value emitted by server controls with ASP.NET 4. Web Deployment Made Awesome: Very nice MIX10 talk by Scott Hanselman on the new web deployment features coming with VS 2010, MSDeploy, and .NET 4.  Makes deploying web applications much, much easier. ASP.NET 4’s Browser Capabilities Support: Nice blog post by Stephen Walther that talks about the new browser definition capabilities support coming with ASP.NET 4. Integrating Twitter into an ASP.NET Website: Nice article by Scott Mitchell that demonstrates how to call and integrate Twitter from within your ASP.NET applications. Improving CSS with .LESS: Nice article by Scott Mitchell that describes how to optimize CSS using .LESS – a free, open source library. ASP.NET MVC Upgrading ASP.NET MVC 1 applications to ASP.NET MVC 2: Eilon Lipton from the ASP.NET team has a nice post that describes how to easily upgrade your ASP.NET MVC 1 applications to ASP.NET MVC 2.  He has an automated tool that makes this easy. Note that automated MVC upgrade support is also built-into VS 2010.  Use the tool in this blog post for updating existing MVC projects using VS 2008. Advanced ASP.NET MVC 2: Nice video talk by Brad Wilson of the ASP.NET MVC team.  In it he describes some of the more advanced features in ASP.NET MVC 2 and how to maximize your productivity with them. Dynamic Select Lists with ASP.NET MVC and jQuery: Michael Ceranski has a nice blog post that describes how to dynamically populate dropdownlists on the client using AJAX. AJAX Microsoft AJAX Minifier: We recently shipped an updated minifier utility that allows you to shrink/minify both JavaScript and CSS files – which can improve the performance of your web applications.  You can run this either manually as a command-line tool or now automatically integrate it using a Visual Studio build task.  You can download it for free here. Visual Studio VS 2010 Tip: Quickly Closing Documents: Nice blog post that describes some techniques for optimizing how windows are closed with the new VS 2010 IDE. Collpase to Definitions with Outlining: Nice tip from Zain on how to collapse your code editor to outline mode using Ctrl + M, Ctrl + O.  Also check out his post on copy/paste with outlining here. $299 VS 2010 Upgrade Offer for VS 2005/2008 Standard Users: Soma blogs about a nice VS 2010 upgrade offer you can take advantage of if you have VS 2005 or VS 2008 Standard editions.  For $299 you can upgrade to VS 2010 Professional edition. Dependency Graphics: Jason Zander (who runs the VS team) has a nice blog post that covers the new dependency graph support within VS 2010.  This makes it easier to visualize the dependencies within your application.  Also check out this video here. Layer Validation: Jason Zander has a nice blog post that talks about the new layer validation features in VS 2010.  This enables you to enforce cleaner layering within your projects and solutions.  VS 2010 Profiler Blog: The VS 2010 Profiler Team has their own blog and on it you can find a bunch of nice posts from the last few months that talk about a lot of the new features coming with VS 2010’s Profiler support.  Some really nice features coming. Silverlight Silverlight 4 Training Course: Nice free set of training courses from Microsoft that can help bring you up to speed on all of the new Silverlight 4 features and how to build applications with them.  Updated and current with the recently released Silverlight 4 RC build and tools. Getting Started with Silverlight and Windows Phone 7 Development: Nice blog post by Tim Heuer that summarizes how to get started building Windows Phone 7 applications using Silverlight.  Also check out my blog post from last week on how to build a Windows Phone 7 Twitter application using Silverlight. A Guide to What Has Changed with the Silverlight 4 RC: Nice summary post by Tim Heuer that describes all of the things that have changed between the Silverlight 4 Beta and the Silverlight 4 RC. Path Based Layout - Part 1 and Part 2: Christian Schormann has a nice blog post about a really cool new feature in Expression Blend 4 and Silverlight 4 called Path Layout. Also check out Andy Beaulieu’s blog post on this. Hope this helps, Scott

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  • The Incremental Architect&rsquo;s Napkin - #5 - Design functions for extensibility and readability

    - by Ralf Westphal
    Originally posted on: http://geekswithblogs.net/theArchitectsNapkin/archive/2014/08/24/the-incremental-architectrsquos-napkin---5---design-functions-for.aspx The functionality of programs is entered via Entry Points. So what we´re talking about when designing software is a bunch of functions handling the requests represented by and flowing in through those Entry Points. Designing software thus consists of at least three phases: Analyzing the requirements to find the Entry Points and their signatures Designing the functionality to be executed when those Entry Points get triggered Implementing the functionality according to the design aka coding I presume, you´re familiar with phase 1 in some way. And I guess you´re proficient in implementing functionality in some programming language. But in my experience developers in general are not experienced in going through an explicit phase 2. “Designing functionality? What´s that supposed to mean?” you might already have thought. Here´s my definition: To design functionality (or functional design for short) means thinking about… well, functions. You find a solution for what´s supposed to happen when an Entry Point gets triggered in terms of functions. A conceptual solution that is, because those functions only exist in your head (or on paper) during this phase. But you may have guess that, because it´s “design” not “coding”. And here is, what functional design is not: It´s not about logic. Logic is expressions (e.g. +, -, && etc.) and control statements (e.g. if, switch, for, while etc.). Also I consider calling external APIs as logic. It´s equally basic. It´s what code needs to do in order to deliver some functionality or quality. Logic is what´s doing that needs to be done by software. Transformations are either done through expressions or API-calls. And then there is alternative control flow depending on the result of some expression. Basically it´s just jumps in Assembler, sometimes to go forward (if, switch), sometimes to go backward (for, while, do). But calling your own function is not logic. It´s not necessary to produce any outcome. Functionality is not enhanced by adding functions (subroutine calls) to your code. Nor is quality increased by adding functions. No performance gain, no higher scalability etc. through functions. Functions are not relevant to functionality. Strange, isn´t it. What they are important for is security of investment. By introducing functions into our code we can become more productive (re-use) and can increase evolvability (higher unterstandability, easier to keep code consistent). That´s no small feat, however. Evolvable code can hardly be overestimated. That´s why to me functional design is so important. It´s at the core of software development. To sum this up: Functional design is on a level of abstraction above (!) logical design or algorithmic design. Functional design is only done until you get to a point where each function is so simple you are very confident you can easily code it. Functional design an logical design (which mostly is coding, but can also be done using pseudo code or flow charts) are complementary. Software needs both. If you start coding right away you end up in a tangled mess very quickly. Then you need back out through refactoring. Functional design on the other hand is bloodless without actual code. It´s just a theory with no experiments to prove it. But how to do functional design? An example of functional design Let´s assume a program to de-duplicate strings. The user enters a number of strings separated by commas, e.g. a, b, a, c, d, b, e, c, a. And the program is supposed to clear this list of all doubles, e.g. a, b, c, d, e. There is only one Entry Point to this program: the user triggers the de-duplication by starting the program with the string list on the command line C:\>deduplicate "a, b, a, c, d, b, e, c, a" a, b, c, d, e …or by clicking on a GUI button. This leads to the Entry Point function to get called. It´s the program´s main function in case of the batch version or a button click event handler in the GUI version. That´s the physical Entry Point so to speak. It´s inevitable. What then happens is a three step process: Transform the input data from the user into a request. Call the request handler. Transform the output of the request handler into a tangible result for the user. Or to phrase it a bit more generally: Accept input. Transform input into output. Present output. This does not mean any of these steps requires a lot of effort. Maybe it´s just one line of code to accomplish it. Nevertheless it´s a distinct step in doing the processing behind an Entry Point. Call it an aspect or a responsibility - and you will realize it most likely deserves a function of its own to satisfy the Single Responsibility Principle (SRP). Interestingly the above list of steps is already functional design. There is no logic, but nevertheless the solution is described - albeit on a higher level of abstraction than you might have done yourself. But it´s still on a meta-level. The application to the domain at hand is easy, though: Accept string list from command line De-duplicate Present de-duplicated strings on standard output And this concrete list of processing steps can easily be transformed into code:static void Main(string[] args) { var input = Accept_string_list(args); var output = Deduplicate(input); Present_deduplicated_string_list(output); } Instead of a big problem there are three much smaller problems now. If you think each of those is trivial to implement, then go for it. You can stop the functional design at this point. But maybe, just maybe, you´re not so sure how to go about with the de-duplication for example. Then just implement what´s easy right now, e.g.private static string Accept_string_list(string[] args) { return args[0]; } private static void Present_deduplicated_string_list( string[] output) { var line = string.Join(", ", output); Console.WriteLine(line); } Accept_string_list() contains logic in the form of an API-call. Present_deduplicated_string_list() contains logic in the form of an expression and an API-call. And then repeat the functional design for the remaining processing step. What´s left is the domain logic: de-duplicating a list of strings. How should that be done? Without any logic at our disposal during functional design you´re left with just functions. So which functions could make up the de-duplication? Here´s a suggestion: De-duplicate Parse the input string into a true list of strings. Register each string in a dictionary/map/set. That way duplicates get cast away. Transform the data structure into a list of unique strings. Processing step 2 obviously was the core of the solution. That´s where real creativity was needed. That´s the core of the domain. But now after this refinement the implementation of each step is easy again:private static string[] Parse_string_list(string input) { return input.Split(',') .Select(s => s.Trim()) .ToArray(); } private static Dictionary<string,object> Compile_unique_strings(string[] strings) { return strings.Aggregate( new Dictionary<string, object>(), (agg, s) => { agg[s] = null; return agg; }); } private static string[] Serialize_unique_strings( Dictionary<string,object> dict) { return dict.Keys.ToArray(); } With these three additional functions Main() now looks like this:static void Main(string[] args) { var input = Accept_string_list(args); var strings = Parse_string_list(input); var dict = Compile_unique_strings(strings); var output = Serialize_unique_strings(dict); Present_deduplicated_string_list(output); } I think that´s very understandable code: just read it from top to bottom and you know how the solution to the problem works. It´s a mirror image of the initial design: Accept string list from command line Parse the input string into a true list of strings. Register each string in a dictionary/map/set. That way duplicates get cast away. Transform the data structure into a list of unique strings. Present de-duplicated strings on standard output You can even re-generate the design by just looking at the code. Code and functional design thus are always in sync - if you follow some simple rules. But about that later. And as a bonus: all the functions making up the process are small - which means easy to understand, too. So much for an initial concrete example. Now it´s time for some theory. Because there is method to this madness ;-) The above has only scratched the surface. Introducing Flow Design Functional design starts with a given function, the Entry Point. Its goal is to describe the behavior of the program when the Entry Point is triggered using a process, not an algorithm. An algorithm consists of logic, a process on the other hand consists just of steps or stages. Each processing step transforms input into output or a side effect. Also it might access resources, e.g. a printer, a database, or just memory. Processing steps thus can rely on state of some sort. This is different from Functional Programming, where functions are supposed to not be stateful and not cause side effects.[1] In its simplest form a process can be written as a bullet point list of steps, e.g. Get data from user Output result to user Transform data Parse data Map result for output Such a compilation of steps - possibly on different levels of abstraction - often is the first artifact of functional design. It can be generated by a team in an initial design brainstorming. Next comes ordering the steps. What should happen first, what next etc.? Get data from user Parse data Transform data Map result for output Output result to user That´s great for a start into functional design. It´s better than starting to code right away on a given function using TDD. Please get me right: TDD is a valuable practice. But it can be unnecessarily hard if the scope of a functionn is too large. But how do you know beforehand without investing some thinking? And how to do this thinking in a systematic fashion? My recommendation: For any given function you´re supposed to implement first do a functional design. Then, once you´re confident you know the processing steps - which are pretty small - refine and code them using TDD. You´ll see that´s much, much easier - and leads to cleaner code right away. For more information on this approach I call “Informed TDD” read my book of the same title. Thinking before coding is smart. And writing down the solution as a bunch of functions possibly is the simplest thing you can do, I´d say. It´s more according to the KISS (Keep It Simple, Stupid) principle than returning constants or other trivial stuff TDD development often is started with. So far so good. A simple ordered list of processing steps will do to start with functional design. As shown in the above example such steps can easily be translated into functions. Moving from design to coding thus is simple. However, such a list does not scale. Processing is not always that simple to be captured in a list. And then the list is just text. Again. Like code. That means the design is lacking visuality. Textual representations need more parsing by your brain than visual representations. Plus they are limited in their “dimensionality”: text just has one dimension, it´s sequential. Alternatives and parallelism are hard to encode in text. In addition the functional design using numbered lists lacks data. It´s not visible what´s the input, output, and state of the processing steps. That´s why functional design should be done using a lightweight visual notation. No tool is necessary to draw such designs. Use pen and paper; a flipchart, a whiteboard, or even a napkin is sufficient. Visualizing processes The building block of the functional design notation is a functional unit. I mostly draw it like this: Something is done, it´s clear what goes in, it´s clear what comes out, and it´s clear what the processing step requires in terms of state or hardware. Whenever input flows into a functional unit it gets processed and output is produced and/or a side effect occurs. Flowing data is the driver of something happening. That´s why I call this approach to functional design Flow Design. It´s about data flow instead of control flow. Control flow like in algorithms is of no concern to functional design. Thinking about control flow simply is too low level. Once you start with control flow you easily get bogged down by tons of details. That´s what you want to avoid during design. Design is supposed to be quick, broad brush, abstract. It should give overview. But what about all the details? As Robert C. Martin rightly said: “Programming is abot detail”. Detail is a matter of code. Once you start coding the processing steps you designed you can worry about all the detail you want. Functional design does not eliminate all the nitty gritty. It just postpones tackling them. To me that´s also an example of the SRP. Function design has the responsibility to come up with a solution to a problem posed by a single function (Entry Point). And later coding has the responsibility to implement the solution down to the last detail (i.e. statement, API-call). TDD unfortunately mixes both responsibilities. It´s just coding - and thereby trying to find detailed implementations (green phase) plus getting the design right (refactoring). To me that´s one reason why TDD has failed to deliver on its promise for many developers. Using functional units as building blocks of functional design processes can be depicted very easily. Here´s the initial process for the example problem: For each processing step draw a functional unit and label it. Choose a verb or an “action phrase” as a label, not a noun. Functional design is about activities, not state or structure. Then make the output of an upstream step the input of a downstream step. Finally think about the data that should flow between the functional units. Write the data above the arrows connecting the functional units in the direction of the data flow. Enclose the data description in brackets. That way you can clearly see if all flows have already been specified. Empty brackets mean “no data is flowing”, but nevertheless a signal is sent. A name like “list” or “strings” in brackets describes the data content. Use lower case labels for that purpose. A name starting with an upper case letter like “String” or “Customer” on the other hand signifies a data type. If you like, you also can combine descriptions with data types by separating them with a colon, e.g. (list:string) or (strings:string[]). But these are just suggestions from my practice with Flow Design. You can do it differently, if you like. Just be sure to be consistent. Flows wired-up in this manner I call one-dimensional (1D). Each functional unit just has one input and/or one output. A functional unit without an output is possible. It´s like a black hole sucking up input without producing any output. Instead it produces side effects. A functional unit without an input, though, does make much sense. When should it start to work? What´s the trigger? That´s why in the above process even the first processing step has an input. If you like, view such 1D-flows as pipelines. Data is flowing through them from left to right. But as you can see, it´s not always the same data. It get´s transformed along its passage: (args) becomes a (list) which is turned into (strings). The Principle of Mutual Oblivion A very characteristic trait of flows put together from function units is: no functional units knows another one. They are all completely independent of each other. Functional units don´t know where their input is coming from (or even when it´s gonna arrive). They just specify a range of values they can process. And they promise a certain behavior upon input arriving. Also they don´t know where their output is going. They just produce it in their own time independent of other functional units. That means at least conceptually all functional units work in parallel. Functional units don´t know their “deployment context”. They now nothing about the overall flow they are place in. They are just consuming input from some upstream, and producing output for some downstream. That makes functional units very easy to test. At least as long as they don´t depend on state or resources. I call this the Principle of Mutual Oblivion (PoMO). Functional units are oblivious of others as well as an overall context/purpose. They are just parts of a whole focused on a single responsibility. How the whole is built, how a larger goal is achieved, is of no concern to the single functional units. By building software in such a manner, functional design interestingly follows nature. Nature´s building blocks for organisms also follow the PoMO. The cells forming your body do not know each other. Take a nerve cell “controlling” a muscle cell for example:[2] The nerve cell does not know anything about muscle cells, let alone the specific muscel cell it is “attached to”. Likewise the muscle cell does not know anything about nerve cells, let a lone a specific nerve cell “attached to” it. Saying “the nerve cell is controlling the muscle cell” thus only makes sense when viewing both from the outside. “Control” is a concept of the whole, not of its parts. Control is created by wiring-up parts in a certain way. Both cells are mutually oblivious. Both just follow a contract. One produces Acetylcholine (ACh) as output, the other consumes ACh as input. Where the ACh is going, where it´s coming from neither cell cares about. Million years of evolution have led to this kind of division of labor. And million years of evolution have produced organism designs (DNA) which lead to the production of these different cell types (and many others) and also to their co-location. The result: the overall behavior of an organism. How and why this happened in nature is a mystery. For our software, though, it´s clear: functional and quality requirements needs to be fulfilled. So we as developers have to become “intelligent designers” of “software cells” which we put together to form a “software organism” which responds in satisfying ways to triggers from it´s environment. My bet is: If nature gets complex organisms working by following the PoMO, who are we to not apply this recipe for success to our much simpler “machines”? So my rule is: Wherever there is functionality to be delivered, because there is a clear Entry Point into software, design the functionality like nature would do it. Build it from mutually oblivious functional units. That´s what Flow Design is about. In that way it´s even universal, I´d say. Its notation can also be applied to biology: Never mind labeling the functional units with nouns. That´s ok in Flow Design. You´ll do that occassionally for functional units on a higher level of abstraction or when their purpose is close to hardware. Getting a cockroach to roam your bedroom takes 1,000,000 nerve cells (neurons). Getting the de-duplication program to do its job just takes 5 “software cells” (functional units). Both, though, follow the same basic principle. Translating functional units into code Moving from functional design to code is no rocket science. In fact it´s straightforward. There are two simple rules: Translate an input port to a function. Translate an output port either to a return statement in that function or to a function pointer visible to that function. The simplest translation of a functional unit is a function. That´s what you saw in the above example. Functions are mutually oblivious. That why Functional Programming likes them so much. It makes them composable. Which is the reason, nature works according to the PoMO. Let´s be clear about one thing: There is no dependency injection in nature. For all of an organism´s complexity no DI container is used. Behavior is the result of smooth cooperation between mutually oblivious building blocks. Functions will often be the adequate translation for the functional units in your designs. But not always. Take for example the case, where a processing step should not always produce an output. Maybe the purpose is to filter input. Here the functional unit consumes words and produces words. But it does not pass along every word flowing in. Some words are swallowed. Think of a spell checker. It probably should not check acronyms for correctness. There are too many of them. Or words with no more than two letters. Such words are called “stop words”. In the above picture the optionality of the output is signified by the astrisk outside the brackets. It means: Any number of (word) data items can flow from the functional unit for each input data item. It might be none or one or even more. This I call a stream of data. Such behavior cannot be translated into a function where output is generated with return. Because a function always needs to return a value. So the output port is translated into a function pointer or continuation which gets passed to the subroutine when called:[3]void filter_stop_words( string word, Action<string> onNoStopWord) { if (...check if not a stop word...) onNoStopWord(word); } If you want to be nitpicky you might call such a function pointer parameter an injection. And technically you´re right. Conceptually, though, it´s not an injection. Because the subroutine is not functionally dependent on the continuation. Firstly continuations are procedures, i.e. subroutines without a return type. Remember: Flow Design is about unidirectional data flow. Secondly the name of the formal parameter is chosen in a way as to not assume anything about downstream processing steps. onNoStopWord describes a situation (or event) within the functional unit only. Translating output ports into function pointers helps keeping functional units mutually oblivious in cases where output is optional or produced asynchronically. Either pass the function pointer to the function upon call. Or make it global by putting it on the encompassing class. Then it´s called an event. In C# that´s even an explicit feature.class Filter { public void filter_stop_words( string word) { if (...check if not a stop word...) onNoStopWord(word); } public event Action<string> onNoStopWord; } When to use a continuation and when to use an event dependens on how a functional unit is used in flows and how it´s packed together with others into classes. You´ll see examples further down the Flow Design road. Another example of 1D functional design Let´s see Flow Design once more in action using the visual notation. How about the famous word wrap kata? Robert C. Martin has posted a much cited solution including an extensive reasoning behind his TDD approach. So maybe you want to compare it to Flow Design. The function signature given is:string WordWrap(string text, int maxLineLength) {...} That´s not an Entry Point since we don´t see an application with an environment and users. Nevertheless it´s a function which is supposed to provide a certain functionality. The text passed in has to be reformatted. The input is a single line of arbitrary length consisting of words separated by spaces. The output should consist of one or more lines of a maximum length specified. If a word is longer than a the maximum line length it can be split in multiple parts each fitting in a line. Flow Design Let´s start by brainstorming the process to accomplish the feat of reformatting the text. What´s needed? Words need to be assembled into lines Words need to be extracted from the input text The resulting lines need to be assembled into the output text Words too long to fit in a line need to be split Does sound about right? I guess so. And it shows a kind of priority. Long words are a special case. So maybe there is a hint for an incremental design here. First let´s tackle “average words” (words not longer than a line). Here´s the Flow Design for this increment: The the first three bullet points turned into functional units with explicit data added. As the signature requires a text is transformed into another text. See the input of the first functional unit and the output of the last functional unit. In between no text flows, but words and lines. That´s good to see because thereby the domain is clearly represented in the design. The requirements are talking about words and lines and here they are. But note the asterisk! It´s not outside the brackets but inside. That means it´s not a stream of words or lines, but lists or sequences. For each text a sequence of words is output. For each sequence of words a sequence of lines is produced. The asterisk is used to abstract from the concrete implementation. Like with streams. Whether the list of words gets implemented as an array or an IEnumerable is not important during design. It´s an implementation detail. Does any processing step require further refinement? I don´t think so. They all look pretty “atomic” to me. And if not… I can always backtrack and refine a process step using functional design later once I´ve gained more insight into a sub-problem. Implementation The implementation is straightforward as you can imagine. The processing steps can all be translated into functions. Each can be tested easily and separately. Each has a focused responsibility. And the process flow becomes just a sequence of function calls: Easy to understand. It clearly states how word wrapping works - on a high level of abstraction. And it´s easy to evolve as you´ll see. Flow Design - Increment 2 So far only texts consisting of “average words” are wrapped correctly. Words not fitting in a line will result in lines too long. Wrapping long words is a feature of the requested functionality. Whether it´s there or not makes a difference to the user. To quickly get feedback I decided to first implement a solution without this feature. But now it´s time to add it to deliver the full scope. Fortunately Flow Design automatically leads to code following the Open Closed Principle (OCP). It´s easy to extend it - instead of changing well tested code. How´s that possible? Flow Design allows for extension of functionality by inserting functional units into the flow. That way existing functional units need not be changed. The data flow arrow between functional units is a natural extension point. No need to resort to the Strategy Pattern. No need to think ahead where extions might need to be made in the future. I just “phase in” the remaining processing step: Since neither Extract words nor Reformat know of their environment neither needs to be touched due to the “detour”. The new processing step accepts the output of the existing upstream step and produces data compatible with the existing downstream step. Implementation - Increment 2 A trivial implementation checking the assumption if this works does not do anything to split long words. The input is just passed on: Note how clean WordWrap() stays. The solution is easy to understand. A developer looking at this code sometime in the future, when a new feature needs to be build in, quickly sees how long words are dealt with. Compare this to Robert C. Martin´s solution:[4] How does this solution handle long words? Long words are not even part of the domain language present in the code. At least I need considerable time to understand the approach. Admittedly the Flow Design solution with the full implementation of long word splitting is longer than Robert C. Martin´s. At least it seems. Because his solution does not cover all the “word wrap situations” the Flow Design solution handles. Some lines would need to be added to be on par, I guess. But even then… Is a difference in LOC that important as long as it´s in the same ball park? I value understandability and openness for extension higher than saving on the last line of code. Simplicity is not just less code, it´s also clarity in design. But don´t take my word for it. Try Flow Design on larger problems and compare for yourself. What´s the easier, more straightforward way to clean code? And keep in mind: You ain´t seen all yet ;-) There´s more to Flow Design than described in this chapter. In closing I hope I was able to give you a impression of functional design that makes you hungry for more. To me it´s an inevitable step in software development. Jumping from requirements to code does not scale. And it leads to dirty code all to quickly. Some thought should be invested first. Where there is a clear Entry Point visible, it´s functionality should be designed using data flows. Because with data flows abstraction is possible. For more background on why that´s necessary read my blog article here. For now let me point out to you - if you haven´t already noticed - that Flow Design is a general purpose declarative language. It´s “programming by intention” (Shalloway et al.). Just write down how you think the solution should work on a high level of abstraction. This breaks down a large problem in smaller problems. And by following the PoMO the solutions to those smaller problems are independent of each other. So they are easy to test. Or you could even think about getting them implemented in parallel by different team members. Flow Design not only increases evolvability, but also helps becoming more productive. All team members can participate in functional design. This goes beyon collective code ownership. We´re talking collective design/architecture ownership. Because with Flow Design there is a common visual language to talk about functional design - which is the foundation for all other design activities.   PS: If you like what you read, consider getting my ebook “The Incremental Architekt´s Napkin”. It´s where I compile all the articles in this series for easier reading. I like the strictness of Function Programming - but I also find it quite hard to live by. And it certainly is not what millions of programmers are used to. Also to me it seems, the real world is full of state and side effects. So why give them such a bad image? That´s why functional design takes a more pragmatic approach. State and side effects are ok for processing steps - but be sure to follow the SRP. Don´t put too much of it into a single processing step. ? Image taken from www.physioweb.org ? My code samples are written in C#. C# sports typed function pointers called delegates. Action is such a function pointer type matching functions with signature void someName(T t). Other languages provide similar ways to work with functions as first class citizens - even Java now in version 8. I trust you find a way to map this detail of my translation to your favorite programming language. I know it works for Java, C++, Ruby, JavaScript, Python, Go. And if you´re using a Functional Programming language it´s of course a no brainer. ? Taken from his blog post “The Craftsman 62, The Dark Path”. ?

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  • Big Data – Buzz Words: What is MapReduce – Day 7 of 21

    - by Pinal Dave
    In yesterday’s blog post we learned what is Hadoop. In this article we will take a quick look at one of the four most important buzz words which goes around Big Data – MapReduce. What is MapReduce? MapReduce was designed by Google as a programming model for processing large data sets with a parallel, distributed algorithm on a cluster. Though, MapReduce was originally Google proprietary technology, it has been quite a generalized term in the recent time. MapReduce comprises a Map() and Reduce() procedures. Procedure Map() performance filtering and sorting operation on data where as procedure Reduce() performs a summary operation of the data. This model is based on modified concepts of the map and reduce functions commonly available in functional programing. The library where procedure Map() and Reduce() belongs is written in many different languages. The most popular free implementation of MapReduce is Apache Hadoop which we will explore tomorrow. Advantages of MapReduce Procedures The MapReduce Framework usually contains distributed servers and it runs various tasks in parallel to each other. There are various components which manages the communications between various nodes of the data and provides the high availability and fault tolerance. Programs written in MapReduce functional styles are automatically parallelized and executed on commodity machines. The MapReduce Framework takes care of the details of partitioning the data and executing the processes on distributed server on run time. During this process if there is any disaster the framework provides high availability and other available modes take care of the responsibility of the failed node. As you can clearly see more this entire MapReduce Frameworks provides much more than just Map() and Reduce() procedures; it provides scalability and fault tolerance as well. A typical implementation of the MapReduce Framework processes many petabytes of data and thousands of the processing machines. How do MapReduce Framework Works? A typical MapReduce Framework contains petabytes of the data and thousands of the nodes. Here is the basic explanation of the MapReduce Procedures which uses this massive commodity of the servers. Map() Procedure There is always a master node in this infrastructure which takes an input. Right after taking input master node divides it into smaller sub-inputs or sub-problems. These sub-problems are distributed to worker nodes. A worker node later processes them and does necessary analysis. Once the worker node completes the process with this sub-problem it returns it back to master node. Reduce() Procedure All the worker nodes return the answer to the sub-problem assigned to them to master node. The master node collects the answer and once again aggregate that in the form of the answer to the original big problem which was assigned master node. The MapReduce Framework does the above Map () and Reduce () procedure in the parallel and independent to each other. All the Map() procedures can run parallel to each other and once each worker node had completed their task they can send it back to master code to compile it with a single answer. This particular procedure can be very effective when it is implemented on a very large amount of data (Big Data). The MapReduce Framework has five different steps: Preparing Map() Input Executing User Provided Map() Code Shuffle Map Output to Reduce Processor Executing User Provided Reduce Code Producing the Final Output Here is the Dataflow of MapReduce Framework: Input Reader Map Function Partition Function Compare Function Reduce Function Output Writer In a future blog post of this 31 day series we will explore various components of MapReduce in Detail. MapReduce in a Single Statement MapReduce is equivalent to SELECT and GROUP BY of a relational database for a very large database. Tomorrow In tomorrow’s blog post we will discuss Buzz Word – HDFS. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • “Query cost (relative to the batch)” <> Query cost relative to batch

    - by Dave Ballantyne
    OK, so that is quite a contradictory title, but unfortunately it is true that a common misconception is that the query with the highest percentage relative to batch is the worst performing.  Simply put, it is a lie, or more accurately we dont understand what these figures mean. Consider the two below simple queries: SELECT * FROM Person.BusinessEntity JOIN Person.BusinessEntityAddress ON Person.BusinessEntity.BusinessEntityID = Person.BusinessEntityAddress.BusinessEntityID go SELECT * FROM Sales.SalesOrderDetail JOIN Sales.SalesOrderHeader ON Sales.SalesOrderDetail.SalesOrderID = Sales.SalesOrderHeader.SalesOrderID After executing these and looking at the plans, I see this : So, a 13% / 87% split ,  but 13% / 87% of WHAT ? CPU ? Duration ? Reads ? Writes ? or some magical weighted algorithm ?  In a Profiler trace of the two we can find the metrics we are interested in. CPU and duration are well out but what about reads (210 and 1935)? To save you doing the maths, though you are more than welcome to, that’s a 90.2% / 9.8% split.  Close, but no cigar. Lets try a different tact.  Looking at the execution plan the “Estimated Subtree cost” of query 1 is 0.29449 and query 2 its 1.96596.  Again to save you the maths that works out to 13.03% and 86.97%, round those and thats the figures we are after.  But, what is the worrying word there ? “Estimated”.  So these are not “actual”  execution costs,  but what’s the problem in comparing the estimated costs to derive a meaning of “Most Costly”.  Well, in the case of simple queries such as the above , probably not a lot.  In more complicated queries , a fair bit. By modifying the second query to also show the total number of lines on each order SELECT *,COUNT(*) OVER (PARTITION BY Sales.SalesOrderDetail.SalesOrderID) FROM Sales.SalesOrderDetail JOIN Sales.SalesOrderHeader ON Sales.SalesOrderDetail.SalesOrderID = Sales.SalesOrderHeader.SalesOrderID The split in percentages is now 6% / 94% and the profiler metrics are : Even more of a discrepancy. Estimates can be out with actuals for a whole host of reasons,  scalar UDF’s are a particular bug bear of mine and in-fact the cost of a udf call is entirely hidden inside the execution plan.  It always estimates to 0 (well, a very small number). Take for instance the following udf Create Function dbo.udfSumSalesForCustomer(@CustomerId integer) returns money as begin Declare @Sum money Select @Sum= SUM(SalesOrderHeader.TotalDue) from Sales.SalesOrderHeader where CustomerID = @CustomerId return @Sum end If we have two statements , one that fires the udf and another that doesn't: Select CustomerID from Sales.Customer order by CustomerID go Select CustomerID,dbo.udfSumSalesForCustomer(Customer.CustomerID) from Sales.Customer order by CustomerID The costs relative to batch is a 50/50 split, but the has to be an actual cost of firing the udf. Indeed profiler shows us : No where even remotely near 50/50!!!! Moving forward to window framing functionality in SQL Server 2012 the optimizer sees ROWS and RANGE ( see here for their functional differences) as the same ‘cost’ too SELECT SalesOrderDetailID,SalesOrderId, SUM(LineTotal) OVER(PARTITION BY salesorderid ORDER BY Salesorderdetailid RANGE unbounded preceding) from Sales.SalesOrderdetail go SELECT SalesOrderDetailID,SalesOrderId, SUM(LineTotal) OVER(PARTITION BY salesorderid ORDER BY Salesorderdetailid Rows unbounded preceding) from Sales.SalesOrderdetail By now it wont be a great display to show you the Profiler trace reads a *tiny* bit different. So moral of the story, Percentage relative to batch can give a rough ‘finger in the air’ measurement, but dont rely on it as fact.

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  • Creating an ASP.NET report using Visual Studio 2010 - Part 2

    - by rajbk
    We continue building our report in this three part series. Creating an ASP.NET report using Visual Studio 2010 - Part 1 Creating an ASP.NET report using Visual Studio 2010 - Part 3 Creating the Client Report Definition file (RDLC) Add a folder called “RDLC”. This will hold our RDLC report.   Right click on the RDLC folder, select “Add new item..” and add an “RDLC” name of “Products”. We will use the “Report Wizard” to walk us through the steps of creating the RDLC.   In the next dialog, give the dataset a name called “ProductDataSet”. Change the data source to “NorthwindReports.DAL” and select “ProductRepository(GetProductsProjected)”. The fields that are returned from the method are shown on the right. Click next.   Drag and drop the ProductName, CategoryName, UnitPrice and Discontinued into the Values container. Note that you can create much more complex grouping using this UI. Click Next.   Most of the selections on this screen are grayed out because we did not choose a grouping in the previous screen. Click next. Choose a style for your report. Click next. The report graphic design surface is now visible. Right click on the report and add a page header and page footer. With the report design surface active, drag and drop a TextBox from the tool box to the page header. Drag one more textbox to the page header. We will use the text boxes to add some header text as shown in the next figure. You can change the font size and other properties of the textboxes using the formatting tool bar (marked in red). You can also resize the columns by moving your cursor in between columns and dragging. Adding Expressions Add two more text boxes to the page footer. We will use these to add the time the report was generated and page numbers. Right click on the first textbox in the page footer and select “Expression”. Add the following expression for the print date (note the = sign at the left of the expression in the dialog below) "© Northwind Traders " & Format(Now(),"MM/dd/yyyy hh:mm tt") Right click on the second text box and add the following for the page count.   Globals.PageNumber & " of " & Globals.TotalPages Formatting the page footer is complete.   We are now going to format the “Unit Price” column so it displays the number in currency format.  Right click on the [UnitPrice] column (not header) and select “Text Box Properties..” Under “Number”, select “Currency”. Hit OK. Adding a chart With the design surface active, go to the toolbox and drag and drop a chart control. You will need to move the product list table down first to make space for the chart contorl. The document can also be resized by dragging on the corner or at the page header/footer separator. In the next dialog, pick the first chart type. This can be changed later if needed. Click OK. The chart gets added to the design surface.   Click on the blue bars in the chart (not legend). This will bring up drop locations for dropping the fields. Drag and drop the UnitPrice and CategoryName into the top (y axis) and bottom (x axis) as shown below. This will give us the total unit prices for a given category. That is the best I could come up with as far as what report to render, sorry :-) Delete the legend area to get more screen estate. Resize the chart to your liking. Change the header, x axis and y axis text by double clicking on those areas. We made it this far. Let’s impress the client by adding a gradient to the bar graph :-) Right click on the blue bar and select “Series properties”. Under “Fill”, add a color and secondary color and select the Gradient style. We are done designing our report. In the next section you will see how to add the report to the report viewer control, bind to the data and make it refresh when the filter criteria are changed.   Creating an ASP.NET report using Visual Studio 2010 - Part 3

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  • The dislikes of TDD

    - by andrewstopford
    I enjoy debates about TDD and Brian Harrys blog post is no exception. Brian sounds out what he likes and dislikes about TDD and it's the dislikes I'll focus on. The idea of having unit tests that cover virtually every line of code that I’ve written that I have to refactor every time I refactor my code makes me shudder.  Doing this way makes me take nearly twice as long as it would otherwise take and I don’t feel like I get sufficient benefits from it. Refactoring your tests to match your refactored code sounds like the tests are suffering. Too many hard dependencies with no SOLID concerns are a sure fire reason you would do this. Maybe at the start of a TDD cycle you would need to do this as your design evolves and you remove these dependencies but this should quickly be resolved as you refactor. If you find your self still doing it then stop and look back at your design. Don’t get me wrong, I’m a big fan of unit tests.  I just prefer to write them after the code has stopped shaking a bit.  In fact most of my early testing is “manual”.  Either I write a small UI on top of my service that allows me to plug in values and try it or write some quick API tests that I throw away as soon as I have validated them. The problem with this is that a UI can make assumptions on your code that then just unit test around and very quickly the design becomes bad and you technical debt sweeps in. If you want to blackbox test your code with a UI then do so after your TDD cycles not before. This is probably by biggest issue with a literal TDD interpretation.  TDD says you never write a line of code without a failing test to show you need it.  I find it leads developers down a dangerous path.  Without any help from a methodology, I have met way too many developers in my life that “back into a solution”.  By this, I mean they write something, it mostly works and they discover a new requirement so they tack it on, and another and another and when they are done, they’ve got a monstrosity of special cases each designed to handle one specific scenario.  There’s way more code than there should be and it’s way too complicated to understand. I believe in finding general solutions to problems from which all the special cases naturally derive rather than building a solution of special cases.  In my mind, to do this, you have to start by conceptualizing and coding the framework of the general algorithm.  For me, that’s a relatively monolithic exercise. TDD is an development pratice not a methodology, the danger is that the solution becomes a mass of different things that violate DRY. TDD won't solve these problems, only good communication and practices like pairing will help. Above all else an assumption that TDD replaces a methodology is a mistake, combine it with what ever works for your team\business but only good communication will help. A good naming scheme\structure for folders, files and tests can help you and your team isolate what tests are for what.

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  • The Top Ten Security Top Ten Lists

    - by Troy Kitch
    As a marketer, we're always putting together the top 3, or 5 best, or an assortment of top ten lists. So instead of going that route, I've put together my top ten security top ten lists. These are not only for security practitioners, but also for the average Joe/Jane; because who isn't concerned about security these days? Now, there might not be ten for each one of these lists, but the title works best that way. Starting with my number ten (in no particular order): 10. Top 10 Most Influential Security-Related Movies Amrit Williams pulls together a great collection of security-related movies. He asks for comments on which one made you want to get into the business. I would have to say that my most influential movie(s), that made me want to get into the business of "stopping the bad guys" would have to be the James Bond series. I grew up on James Bond movies: thwarting the bad guy and saving the world. I recall being both ecstatic and worried when Silicon Valley-themed "A View to A Kill" hit theaters: "An investigation of a horse-racing scam leads 007 to a mad industrialist who plans to create a worldwide microchip monopoly by destroying California's Silicon Valley." Yikes! 9. Top Ten Security Careers From movies that got you into the career, here’s a top 10 list of security-related careers. It starts with number then, Information Security Analyst and ends with number one, Malware Analyst. They point out the significant growth in security careers and indicate that "according to the Bureau of Labor Statistics, the field is expected to experience growth rates of 22% between 2010-2020. If you are interested in getting into the field, Oracle has many great opportunities all around the world.  8. Top 125 Network Security Tools A bit outside of the range of 10, the top 125 Network Security Tools is an important list because it includes a prioritized list of key security tools practitioners are using in the hacking community, regardless of whether they are vendor supplied or open source. The exhaustive list provides ratings, reviews, searching, and sorting. 7. Top 10 Security Practices I have to give a shout out to my alma mater, Cal Poly, SLO: Go Mustangs! They have compiled their list of top 10 practices for students and faculty to follow. Educational institutions are a common target of web based attacks and miscellaneous errors according to the 2014 Verizon Data Breach Investigations Report.    6. (ISC)2 Top 10 Safe and Secure Online Tips for Parents This list is arguably the most important list on my list. The tips were "gathered from (ISC)2 member volunteers who participate in the organization’s Safe and Secure Online program, a worldwide initiative that brings top cyber security experts into schools to teach children ages 11-14 how to protect themselves in a cyber-connected world…If you are a parent, educator or organization that would like the Safe and Secure Online presentation delivered at your local school, or would like more information about the program, please visit here.” 5. Top Ten Data Breaches of the Past 12 Months This type of list is always changing, so it's nice to have a current one here from Techrader.com. They've compiled and commented on the top breaches. It is likely that most readers here were effected in some way or another. 4. Top Ten Security Comic Books Although mostly physical security controls, I threw this one in for fun. My vote for #1 (not on the list) would be Professor X. The guy can breach confidentiality, integrity, and availability just by messing with your thoughts. 3. The IOUG Data Security Survey's Top 10+ Threats to Organizations The Independent Oracle Users Group annual survey on enterprise data security, Leaders Vs. Laggards, highlights what Oracle Database users deem as the top 12 threats to their organization. You can find a nice graph on page 9; Figure 7: Greatest Threats to Data Security. 2. The Ten Most Common Database Security Vulnerabilities Though I don't necessarily agree with all of the vulnerabilities in this order...I like a list that focuses on where two-thirds of your sensitive and regulated data resides (Source: IDC).  1. OWASP Top Ten Project The Online Web Application Security Project puts together their annual list of the 10 most critical web application security risks that organizations should be including in their overall security, business risk and compliance plans. In particular, SQL injection risks continues to rear its ugly head each year. Oracle Audit Vault and Database Firewall can help prevent SQL injection attacks and monitor database and system activity as a detective security control. Did I miss any?

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  • SQL SERVER – Puzzle – Statistics are not Updated but are Created Once

    - by pinaldave
    After having excellent response to my quiz – Why SELECT * throws an error but SELECT COUNT(*) does not?I have decided to ask another puzzling question to all of you. I am running this test on SQL Server 2008 R2. Here is the quick scenario about my setup. Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated Note: Auto Update Statistics and Auto Create Statistics for database is TRUE Expected Result – Statistics should be updated – SQL SERVER – When are Statistics Updated – What triggers Statistics to Update Now the question is why the statistics are not updated? The common answer is – we can update the statistics ourselves using UPDATE STATISTICS TableName WITH FULLSCAN, ALL However, the solution I am looking is where statistics should be updated automatically based on algorithm mentioned here. Now the solution is to ____________________. Vinod Kumar is not allowed to take participate over here as he is the one who has helped me to build this puzzle. I will publish the solution on next week. Please leave a comment and if your comment consist valid answer, I will publish with due credit. Here is the script to reproduce the scenario which I mentioned. -- Execution Plans Difference -- Create Sample Database CREATE DATABASE SampleDB GO USE SampleDB GO -- Create Table CREATE TABLE ExecTable (ID INT, FirstName VARCHAR(100), LastName VARCHAR(100), City VARCHAR(100)) GO -- Insert One Thousand Records -- INSERT 1 INSERT INTO ExecTable (ID,FirstName,LastName,City) SELECT TOP 1000 ROW_NUMBER() OVER (ORDER BY a.name) RowID, 'Bob', CASE WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%20 = 1 THEN 'New York' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 5 THEN 'San Marino' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 3 THEN 'Los Angeles' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 7 THEN 'La Cinega' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 13 THEN 'San Diego' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 17 THEN 'Las Vegas' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Display statistics of the table - none listed sp_helpstats N'ExecTable', 'ALL' GO -- Select Statement SELECT FirstName, LastName, City FROM ExecTable WHERE City  = 'New York' GO -- Display statistics of the table sp_helpstats N'ExecTable', 'ALL' GO -- Replace your Statistics over here -- NOTE: Replace your _WA_Sys with stats from above query DBCC SHOW_STATISTICS('ExecTable', _WA_Sys_00000004_7D78A4E7); GO -------------------------------------------------------------- -- Round 2 -- Insert Ten Thousand Records -- INSERT 2 INSERT INTO ExecTable (ID,FirstName,LastName,City) SELECT TOP 10000 ROW_NUMBER() OVER (ORDER BY a.name) RowID, 'Bob', CASE WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%20 = 1 THEN 'New York' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 5 THEN 'San Marino' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 3 THEN 'Los Angeles' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 7 THEN 'La Cinega' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 13 THEN 'San Diego' WHEN  ROW_NUMBER() OVER (ORDER BY a.name)%20 = 17 THEN 'Las Vegas' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Select Statement SELECT FirstName, LastName, City FROM ExecTable WHERE City  = 'New York' GO -- Display statistics of the table sp_helpstats N'ExecTable', 'ALL' GO -- Replace your Statistics over here -- NOTE: Replace your _WA_Sys with stats from above query DBCC SHOW_STATISTICS('ExecTable', _WA_Sys_00000004_7D78A4E7); GO -- You will notice that Statistics are still updated with 1000 rows -- Clean up Database DROP TABLE ExecTable GO USE MASTER GO ALTER DATABASE SampleDB SET SINGLE_USER WITH ROLLBACK IMMEDIATE; GO DROP DATABASE SampleDB GO Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Index, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: SQL Statistics, Statistics

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  • Social Business Forum Milano: Day 2

    - by me
    @YourService. The business world has flipped and small business can capitalize  by Frank Eliason (twitter: @FrankEliason ) Technology and social media tools have made it easier than ever for companies to communicate with consumers. They can listen and join in on conversations, solve problems, get instant feedback about their products and services, and more. So why, then, are most companies not doing this? Instead, it seems as if customer service is at an all time low, and that the few companies who are choosing to focus on their customers are experiencing a great competitive advantage. At Your Service explains the importance of refocusing your business on your customers and your employees, and just how to do it. Explains how to create a culture of empowered employees who understand the value of a great customer experience Advises on the need to communicate that experience to their customers and potential customers Frank Eliason, recognized by BusinessWeek as the 'most famous customer service manager in the US, possibly in the world,' has built a reputation for helping large businesses improve the way they connect with customers and enhance their relationships Quotes from the Audience: Bertrand Duperrin ?@bduperrin social service is not about shutting up the loudest cutsomers ! #sbf12 @frankeliason Paolo Pelloni ?@paolopelloniGautam Ghosh ?@GautamGhosh RT @cecildijoux: #sbf12 @frankeliason you need to change things and fix the approach it's not about social media it's about driving change  Peter H. Reiser ?@peterreiser #sbf12 Company Experience = Product Experience + Customer Interactions + Employee Experience @yourservice Engage or lose! Socialize, mobilize, conversify: engage your employees to improve business performance Christian Finn (twitter: @cfinn) First Christian was presenting the flying monkey   Then he outlined the four principals to fix the Intranet: 1. Socalize the Intranet 2. Get Thee to a Single Repository 3. Mobilize the Intranet 4. Conversationalize Your Processes Quotes from the Audience: Oscar Berg ?@oscarberg Engaged employees think their work bring out the best of their ideas @cfinn #sbf12 http://pic.twitter.com/68eddp48 John Stepper ?@johnstepper I like @cfinn's "conversify your processes" A nice related concept to "narrating your work", part of working out loud. http://johnstepper.com/2012/05/26/working-out-loud-your-personal-content-strategy/ Oscar Berg ?@oscarberg Organizations are talent markets - socializing your intranet makes this market function better @cfinn #sbf12 For profit, productivity, and personal benefit: creating a collaborative culture at Deutsche Bank John Stepper (twitter:@johnstepper) Driving adoption of collaboration + social media platforms at Deutsche Bank. John shared some great best practices on how to deploy an enterprise wide  community model  in a large company. He started with the most important question What is the commercial value of adding social ? Then he talked about the success of Community of Practices deployment and outlined some key use cases including the relevant measures to proof the ROI of the investment. Examples:  Community of practice -> measure: systematic collection of value stories  Self-service website  -> measure: based on representative models Optimizing asset inventory - > measure: Actual counts  This use case was particular interesting.  It is a crowd sourced spending/saving of infrastructure model.  User can cancel IT services they don't need (as example Software xx).  5% of the saving goes to social responsibility projects. The John outlined some  best practices on how to address the WIIFM (What's In It For Me) question of the individual users:  - change from hierarchy to graph -  working out loud = observable work + narrating  your work  - add social skills to career objectives - example: building a purposeful social network course/training as part of the job development curriculum And last but not least John gave some important tips on how to get senior management buy-in by establishing management sponsored division level collaboration boards which defines clear uses cases and measures. This divisional use cases are then implemented using a common social platform.  Thanks John - I learned a lot from your presentation!   Quotes from the Audience: Ana Silva ?@AnaDataGirl #sbf12 what's in it for individuals at Deutsche Bank? Shapping their reputations in a big org says @johnstepper #e20Ana Silva ?@AnaDataGirl Any reason why not? MT @magatorlibero #sbf12 is Deutsche B. experience on applying social inside company applicable to Italian people? Oscar Berg ?@oscarberg Your career is not a ladder, it is a network that opens up opportunities - @johnstepper #sbf12 Oscar Berg ?@oscarberg @johnstepper: Institutionalizing collaboration is next - collaboration woven into the fabric of daily work #sbf12 Ana Silva ?@AnaDataGirl #sbf12 @johnstepper talking about how Deutsche Bank is using #socbiz to build purposeful CoP & save money

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  • Using the Katana Authentication handlers with NancyFx

    - by cibrax
    Once you write an OWIN Middleware service, it can be reused everywhere as long as OWIN is supported. In my last post, I discussed how you could write an Authentication Handler in Katana for Hawk (HMAC Authentication). Good news is NancyFx can be run as an OWIN handler, so you can use many of existing middleware services, including the ones that are ship with Katana. Running NancyFx as a OWIN handler is pretty straightforward, and discussed in detail as part of the NancyFx documentation here. After run the steps described there and you have the application working, only a few more steps are required to register the additional middleware services. The example bellow shows how the Startup class is modified to include Hawk authentication. public class Startup { public void Configuration(IAppBuilder app) { app.UseHawkAuthentication(new HawkAuthenticationOptions { Credentials = (id) => { return new HawkCredential { Id = "dh37fgj492je", Key = "werxhqb98rpaxn39848xrunpaw3489ruxnpa98w4rxn", Algorithm = "hmacsha256", User = "steve" }; } }); app.UseNancy(); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This code registers the Hawk Authentication Handler on top of the OWIN pipeline, so it will try to authenticate the calls before the request messages are passed over to NancyFx. The authentication handlers in Katana set the user principal in the OWIN environment using the key “server.User”. The following code shows how you can get that principal in a NancyFx module, public class HomeModule : NancyModule { public HomeModule() { Get["/"] = x => { var env = (IDictionary<string, object>)Context.Items[NancyOwinHost.RequestEnvironmentKey]; if (!env.ContainsKey("server.User") || env["server.User"] == null) { return HttpStatusCode.Unauthorized; } var identity = (ClaimsPrincipal)env["server.User"]; return "Hello " + identity.Identity.Name; }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Thanks to OWIN, you don’t know any details of how these cross cutting concerns can be implemented in every possible web application framework.

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  • Team Leaders & Authors - Manage and Report Workflow using "Print an Outline" in UPK

    - by [email protected]
    Did you know you can "print an outline?" You can print any outline or portion of an outline. Why might you want to "print an outline" in UPK... Have you ever wondered how many topics you have recorded, how many of your topics are ready for review, or even better, how many topics are complete! Do you need to report your project status to management? Maybe you just like to have a copy of your outline to refer to during development. Included in this output is the outline structure as well as the layout defined in the Details View of the Outline Editor. To print an outline, you must open either a module or section in the Outline Editor. A set of default data columns is automatically included in the output; however, you can configure which columns you want to appear in the report by switching to the Details view and customizing the columns. (To learn more about customizing your columns refer to the Add and Remove Columns section of the Content Development.pdf guide) To print an outline from the Outline Editor: 1. Open a module or section document in the Outline Editor. 2. Expand the documents to display the details that you want included in the report. 3. On the File menu, choose Print and use the toolbar icons to print, view, or save the report to a file. Personally, I opt to save my outline in Microsoft Excel. Using the delivered features of Microsoft Excel you can add columns of information, such as development notes, to your outline or you can graph and chart your Project status. As mentioned above you can configure what columns you want to appear in the outline. When utilizing the Print an Outline feature in conjunction with the Managing Workflow features of the UPK Multi-user instance you as a Team Lead or Author can better report project status. Read more about Managing Workflow below. Managing Workflow: The Properties toolpane contains special properties that allow authors to track document status or State as well as assign Document Ownership. Assign Content State The State property is an editable property for communicating the status of a document. This is particularly helpful when collaborating with other authors in a development team. Authors can assign a state to documents from the master list defined by the administrator. The default list of States includes (blank), Not Started, Draft, In Review, and Final. Administrators can customize the list by adding, deleting or renaming the values. To assign a State value to a document: 1. Make sure you are working online. 2. Display the Properties toolpane. 3. Select the document(s) to which you want to assign a state. Note: You can select multiple documents using the standard Windows selection keys (CTRL+click and SHIFT+click). 4. In the Workflow category, click in the State cell. 5. Select a value from the list. Assign Document Ownership In many enterprises, multiple authors often work together developing content in a team environment. Team leaders typically handle large projects by assigning specific development responsibilities to authors. The Owner property allows team leaders and authors to assign documents to themselves and other authors to track who is responsible for a specific document. You view and change document assignments for a document using the Owner property in the Properties toolpane. To assign a document owner: 1. Make sure you are working online. 2. On the View menu, choose Properties. 3. Select the document(s) to which you want to assign document responsibility. Note: You can select multiple documents using the standard Windows selection keys (CTRL+click and SHIFT+click). 4. In the Workflow category, click in the Owner cell. 5. Select a name from the list. Is anyone out there already using this feature? Share your ideas with the group. Those of you new to this feature, give it a test drive and let us know what you think. - Kathryn Lustenberger, Oracle UPK & Tutor Outbound Product Management

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  • Big Data – Beginning Big Data – Day 1 of 21

    - by Pinal Dave
    What is Big Data? I want to learn Big Data. I have no clue where and how to start learning about it. Does Big Data really means data is big? What are the tools and software I need to know to learn Big Data? I often receive questions which I mentioned above. They are good questions and honestly when we search online, it is hard to find authoritative and authentic answers. I have been working with Big Data and NoSQL for a while and I have decided that I will attempt to discuss this subject over here in the blog. In the next 21 days we will understand what is so big about Big Data. Big Data – Big Thing! Big Data is becoming one of the most talked about technology trends nowadays. The real challenge with the big organization is to get maximum out of the data already available and predict what kind of data to collect in the future. How to take the existing data and make it meaningful that it provides us accurate insight in the past data is one of the key discussion points in many of the executive meetings in organizations. With the explosion of the data the challenge has gone to the next level and now a Big Data is becoming the reality in many organizations. Big Data – A Rubik’s Cube I like to compare big data with the Rubik’s cube. I believe they have many similarities. Just like a Rubik’s cube it has many different solutions. Let us visualize a Rubik’s cube solving challenge where there are many experts participating. If you take five Rubik’s cube and mix up the same way and give it to five different expert to solve it. It is quite possible that all the five people will solve the Rubik’s cube in fractions of the seconds but if you pay attention to the same closely, you will notice that even though the final outcome is the same, the route taken to solve the Rubik’s cube is not the same. Every expert will start at a different place and will try to resolve it with different methods. Some will solve one color first and others will solve another color first. Even though they follow the same kind of algorithm to solve the puzzle they will start and end at a different place and their moves will be different at many occasions. It is  nearly impossible to have a exact same route taken by two experts. Big Market and Multiple Solutions Big Data is exactly like a Rubik’s cube – even though the goal of every organization and expert is same to get maximum out of the data, the route and the starting point are different for each organization and expert. As organizations are evaluating and architecting big data solutions they are also learning the ways and opportunities which are related to Big Data. There is not a single solution to big data as well there is not a single vendor which can claim to know all about Big Data. Honestly, Big Data is too big a concept and there are many players – different architectures, different vendors and different technology. What is Next? In this 31 days series we will be exploring many essential topics related to big data. I do not claim that you will be master of the subject after 31 days but I claim that I will be covering following topics in easy to understand language. Architecture of Big Data Big Data a Management and Implementation Different Technologies – Hadoop, Mapreduce Real World Conversations Best Practices Tomorrow In tomorrow’s blog post we will try to answer one of the very essential questions – What is Big Data? Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • SQL SERVER – SSMS: Top Object and Batch Execution Statistics Reports

    - by Pinal Dave
    The month of June till mid of July has been the fever of sports. First, it was Wimbledon Tennis and then the Soccer fever was all over. There is a huge number of fan followers and it is great to see the level at which people sometimes worship these sports. Being an Indian, I cannot forget to mention the India tour of England later part of July. Following these sports and as the events unfold to the finals, there are a number of ways the statisticians can slice and dice the numbers. Cue from soccer I can surely say there is a team performance against another team and then there is individual member fairs against a particular opponent. Such statistics give us a fair idea to how a team in the past or in the recent past has fared against each other, head-to-head stats during World cup and during other neutral venue games. All these statistics are just pointers. In reality, they don’t reflect the calibre of the current team because the individuals who performed in each of these games are totally different (Typical example being the Brazil Vs Germany semi-final match in FIFA 2014). So at times these numbers are misleading. It is worth investigating and get the next level information. Similar to these statistics, SQL Server Management studio is also equipped with a number of reports like a) Object Execution Statistics report and b) Batch Execution Statistics reports. As discussed in the example, the team scorecard is like the Batch Execution statistics and individual stats is like Object Level statistics. The analogy can be taken only this far, trust me there is no correlation between SQL Server functioning and playing sports – It is like I think about diet all the time except while I am eating. Performance – Batch Execution Statistics Let us view the first report which can be invoked from Server Node -> Reports -> Standard Reports -> Performance – Batch Execution Statistics. Most of the values that are displayed in this report come from the DMVs sys.dm_exec_query_stats and sys.dm_exec_sql_text(sql_handle). This report contains 3 distinctive sections as outline below.   Section 1: This is a graphical bar graph representation of Average CPU Time, Average Logical reads and Average Logical Writes for individual batches. The Batch numbers are indicative and the details of individual batch is available in section 3 (detailed below). Section 2: This represents a Pie chart of all the batches by Total CPU Time (%) and Total Logical IO (%) by batches. This graphical representation tells us which batch consumed the highest CPU and IO since the server started, provided plan is available in the cache. Section 3: This is the section where we can find the SQL statements associated with each of the batch Numbers. This also gives us the details of Average CPU / Average Logical Reads and Average Logical Writes in the system for the given batch with object details. Expanding the rows, I will also get the # Executions and # Plans Generated for each of the queries. Performance – Object Execution Statistics The second report worth a look is Object Execution statistics. This is a similar report as the previous but turned on its head by SQL Server Objects. The report has 3 areas to look as above. Section 1 gives the Average CPU, Average IO bar charts for specific objects. The section 2 is a graphical representation of Total CPU by objects and Total Logical IO by objects. The final section details the various objects in detail with the Avg. CPU, IO and other details which are self-explanatory. At a high-level both the reports are based on queries on two DMVs (sys.dm_exec_query_stats and sys.dm_exec_sql_text) and it builds values based on calculations using columns in them: SELECT * FROM    sys.dm_exec_query_stats s1 CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS s2 WHERE   s2.objectid IS NOT NULL AND DB_NAME(s2.dbid) IS NOT NULL ORDER BY  s1.sql_handle; This is one of the simplest form of reports and in future blogs we will look at more complex reports. I truly hope that these reports can give DBAs and developers a hint about what is the possible performance tuning area. As a closing point I must emphasize that all above reports pick up data from the plan cache. If a particular query has consumed a lot of resources earlier, but plan is not available in the cache, none of the above reports would show that bad query. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL Tagged: SQL Reports

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  • Selling Visual Studio ALM

    - by Tarun Arora
    Introduction As a consultant I have been selling Application Lifecycle Management services using Visual Studio and Team Foundation Server. I’ve been contacted various times by friends working in organization telling me that ALM processes in their company were benchmarked when dinosaurs walked the earth. Most of these individuals already know the great features Microsoft ALM tools offer and are keen to start a conversation with the CIO but don’t exactly know where to start. It is very important how you engage in your first conversation, if you start the conversation with ‘There is this great tooling from Microsoft which offers amazing features to boost developer productivity, … ‘ from experience I can tell you the reply from your CIO would be ‘I already know! Our existing landscape has a combination of bleeding edge open source and cutting edge licensed tools which already cover these features quite well, more over Microsoft products have a high licensing cost associated to them.’ You will always find it harder to sell by feature, the trick is to highlight the gap in the existing processes & tools and then highlight the impact of these gaps to the overall development processes, by now you would have captured enough attention to show off how the ALM tooling offered by Microsoft not only fills those gaps but offers great value adds to take their development practices to the next level. Rangers ALM Assessment Guide Image 1 – Welcome! First look at the Rangers ALM assessment guide Most organization already have some processes in place to cover aspects of ALM. How do you go about proving that there isn’t enough cover in place? This is where Visual Studio ALM Rangers ALM Assessment guide can help. The ALM assessment guide is really a tool that helps you gather information about Development practices and processes within a customer's environment. Several questionnaires are used to identify the current state of individual development lifecycle areas and decide on a desired state for those processes. It also presents guidance and roll-up summaries to help with recommendations moving forward. The ALM Rangers assessment guide can be downloaded from here. Image 2 – ALM Assessment guide divided into different functions of SDLC The assessment guide is divided into different functions of Software Development Lifecycle (listed below), this gives you the ability to access how mature the company is in different areas of SDLC. Architecture & Design Requirement Engineering & UX Development Software Configuration Management Governance Deployment & Operations Testing & Quality Assurance Project Planning & Management Each section has a set of questions, fill in the assessment by selecting “Never/Sometimes/Always” from the Answer column in the question sheets.  Each answer has weightage to the overall score. Each question has a link next to it, clicking the link takes you to the Reference sheet which gives you more details about the question along with a reason for “why you need to ask this question?”, “other ways to phrase the question” and “what to expect as an answer from the customer”. The trick is to engage the customer in a discussion. You need to probe a lot, listen to the customer and have a discussion with several team members, preferably without management to ensure that you receive candid feedback. This reminds me of a funny incident when during an ALM review a customer told me that they have a sophisticated semi-automated application deployment process, further discussions revealed that deployment actually involved 72 manual configuration steps per production node. Such observations can be recorded in the Issue Brainstorming worksheet for further consideration later. It is also worth mentioning the different levels of ALM maturity to the customer. By default the desired state of ALM maturity is set to Standard, it is possible to set a desired state by area, you should strive for Advanced or Dynamic, it always helps by explaining the classification and advantages. Image 3 – ALM levels by description The ALM assessment guide helps you arrive at a quantitative measure of the company’s ALM maturity. The resultant graph plotted on a spider’s web shows you the company’s current state of ALM maturity and the desired state of ALM maturity. Further since the results are classified by area you can immediately spot the areas where the customer needs immediate help. Image 4 – The spiders web! The red cross icons are areas shouting out for immediate attention, the yellow exclamation icons are areas that need improvement. These icons are calculated on the difference between the Current State of ALM maturity VS the Desired state of ALM maturity. Image 5 – Results by area Conclusion To conclude the Rangers ALM assessment guide gives you the ability to, Measure the customer’s current ALM maturity level Understand the ALM maturity level the customer desires to achieve Capture a healthy list of issues the customer wants to brainstorm further Now What’s next…? Download and get started with the Rangers ALM Assessment Guide. If you have successfully captured the above listed three pieces of information you are in a great state to make recommendations on the identified areas highlighting the benefits that Visual Studio ALM tools would offer. In the next post I will be covering how to take the ALM assessment results as the base to actually convert your recommendation into a sell.  Remember to subscribe to http://feeds.feedburner.com/TarunArora. I would love to hear your feedback! If you have any recommendations on things that I should consider or any questions or feedback, feel free to leave a comment. *** A special thanks goes out to fellow ranges Willy, Ethem and Philip for reviewing the blog post and providing valuable feedback. ***

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