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• C# 2D Camera Max Zoom

  - by Craig

  I have a simple ship sprite moving around the screen along with a 2D Camera. I have zooming in and out working, however when I zoom out it goes past the world bounds and has the cornflower blue background showing. How do I sort it that I can only zoom out as far as showing the entire world (which is a picture of OZ) and thats it? I dont want any of the cornflower blue showing. Cheers! namespace GamesCoursework_1 { /// <summary> /// This is the main type for your game /// </summary> public class Game1 : Microsoft.Xna.Framework.Game { GraphicsDeviceManager graphics; SpriteBatch spriteBatch; // player variables Texture2D Ship; Vector2 Ship_Position; float Ship_Rotation = 0.0f; Vector2 Ship_Origin; Vector2 Ship_Velocity; const float tangentialVelocity = 4f; float friction = 0.05f; static Point CameraViewport = new Point(800, 800); Camera2d cam = new Camera2d((int)CameraViewport.X, (int)CameraViewport.Y); //Size of world static Point worldSize = new Point(1600, 1600); // Screen variables static Point worldCenter = new Point(worldSize.X / 2, worldSize.Y / 2); Rectangle playerBounds = new Rectangle(CameraViewport.X / 2, CameraViewport.Y / 2, worldSize.X - CameraViewport.X, worldSize.Y - CameraViewport.Y); Rectangle worldBounds = new Rectangle(0, 0, worldSize.X, worldSize.Y); Texture2D background; public Game1() { graphics = new GraphicsDeviceManager(this); graphics.PreferredBackBufferWidth = CameraViewport.X; graphics.PreferredBackBufferHeight = CameraViewport.Y; Content.RootDirectory = "Content"; } /// <summary> /// Allows the game to perform any initialization it needs to before starting to run. /// This is where it can query for any required services and load any non-graphic /// related content. Calling base.Initialize will enumerate through any components /// and initialize them as well. /// </summary> protected override void Initialize() { // TODO: Add your initialization logic here base.Initialize(); } /// <summary> /// LoadContent will be called once per game and is the place to load /// all of your content. /// </summary> protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); // TODO: use this.Content to load your game content here Ship = Content.Load<Texture2D>("Ship"); Ship_Origin.X = Ship.Width / 2; Ship_Origin.Y = Ship.Height / 2; background = Content.Load<Texture2D>("aus"); Ship_Position = new Vector2(worldCenter.X, worldCenter.Y); cam.Pos = Ship_Position; cam.Zoom = 1f; } /// <summary> /// UnloadContent will be called once per game and is the place to unload /// all content. /// </summary> protected override void UnloadContent() { // TODO: Unload any non ContentManager content here } /// <summary> /// Allows the game to run logic such as updating the world, /// checking for collisions, gathering input, and playing audio. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); // TODO: Add your update logic here Ship_Position = Ship_Velocity + Ship_Position; keyPressed(); base.Update(gameTime); } /// <summary> /// This is called when the game should draw itself. /// </summary> /// <param name="gameTime">Provides a snapshot of timing values.</param> protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); // TODO: Add your drawing code here spriteBatch.Begin(SpriteSortMode.Deferred, BlendState.AlphaBlend, null, null, null,null, cam.get_transformation(GraphicsDevice)); spriteBatch.Draw(background, Vector2.Zero, Color.White); spriteBatch.Draw(Ship, Ship_Position, Ship.Bounds, Color.White, Ship_Rotation, Ship_Origin, 1.0f, SpriteEffects.None, 0f); spriteBatch.End(); base.Draw(gameTime); } private void Ship_Move(Vector2 move) { Ship_Position += move; } private void keyPressed() { KeyboardState keyState; // Move right keyState = Keyboard.GetState(); if (keyState.IsKeyDown(Keys.Right)) { Ship_Rotation = Ship_Rotation + 0.1f; } if (keyState.IsKeyDown(Keys.Left)) { Ship_Rotation = Ship_Rotation - 0.1f; } if (keyState.IsKeyDown(Keys.Up)) { Ship_Velocity.X = (float)Math.Cos(Ship_Rotation) * tangentialVelocity; Ship_Velocity.Y = (float)Math.Sin(Ship_Rotation) * tangentialVelocity; if ((int)Ship_Position.Y < playerBounds.Bottom && (int)Ship_Position.Y > playerBounds.Top) cam._pos.Y = Ship_Position.Y; if ((int)Ship_Position.X > playerBounds.Left && (int)Ship_Position.X < playerBounds.Right) cam._pos.X = Ship_Position.X; Ship_Position += new Vector2(tangentialVelocity, 0); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(tangentialVelocity * 2, 0.0f); Ship_Position += new Vector2(-tangentialVelocity, 0.0f); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(-tangentialVelocity * 2, 0.0f); Ship_Position += new Vector2(0.0f, -tangentialVelocity); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(0.0f, -tangentialVelocity * 2); Ship_Position += new Vector2(0.0f, tangentialVelocity); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(0.0f, 2 * tangentialVelocity); } else if(Ship_Velocity != Vector2.Zero) { float i = Ship_Velocity.X; float j = Ship_Velocity.Y; Ship_Velocity.X = i -= friction * i; Ship_Velocity.Y = j -= friction * j; if ((int)Ship_Position.Y < playerBounds.Bottom && (int)Ship_Position.Y > playerBounds.Top) cam._pos.Y = Ship_Position.Y; if ((int)Ship_Position.X > playerBounds.Left && (int)Ship_Position.X < playerBounds.Right) cam._pos.X = Ship_Position.X; Ship_Position += new Vector2(tangentialVelocity, 0); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(tangentialVelocity * 2, 0.0f); Ship_Position += new Vector2(-tangentialVelocity, 0.0f); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(-tangentialVelocity * 2, 0.0f); Ship_Position += new Vector2(0.0f, -tangentialVelocity); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(0.0f, -tangentialVelocity * 2); Ship_Position += new Vector2(0.0f, tangentialVelocity); if (!worldBounds.Contains(new Point((int)Ship_Position.X, (int)Ship_Position.Y))) Ship_Position -= new Vector2(0.0f, 2 * tangentialVelocity); } if (keyState.IsKeyDown(Keys.Q)) { if (cam.Zoom < 2f) cam.Zoom += 0.05f; } if (keyState.IsKeyDown(Keys.A)) { if (cam.Zoom > 0.3f) cam.Zoom -= 0.05f; } } } }

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• Functional Programming, JavaScript and UI - some neophyte questions

  - by jamesson

  This has been discussed in other threads, however I am hoping for some comments relevant to UI and an explanation of some vitriol I had flung my way in a Certain IRC Channel Which shall remain nameless. In the discussion here, the comments in the accepted answer suggest that I approach the given code from a functional perspective, which was new to me at the time. Wikipedia said, among other things, that FP "avoids state and mutable data", which includes according to the discussion global vars. Now, being that I am already pretty far along in my project I am not going to learn FP before I finish, but... How is it possible to avoid global vars if, for instance, I have a UI whose entire functionality changes if a mousebutton is down? I have a number of things like this. Why was there a strong negative reaction in the Certain IRC channel to implementing FP in JS? When I Brought up what seemed to me to be supportive comments by Crockford, people got even madder. Now, this being IRC there is no rep system, but they at least gave indication of having read TGP (which I haven't gotten to yet) so I'm assuming they're not idiots. Many thanks in advance Joe

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• Make Gameobject Stand On Surface Facing Certain Direction

  - by Julian

  I want to make a biped character stand on any surface I click on. Surfaces have up vectors of any of positive or negative X,Y,Z. So imagine a cube with each face being a gameobject whose up vector pointing directly away from the cube. If my character is facing "forward" and I click on a surface which is to the left or right of me ( left or right walls), I want my character to now be standing on that surface but still be facing in the direction he initially was. If I click on a wall which is in the forward path of my character i want him to now be standing on that surface and his forward to now be what was once "up" relative to my character. Here is the code I am working with now. void Update() { if (Input.GetMouseButtonUp (0)) { RaycastHit hit; var ray = Camera.main.ScreenPointToRay(Input.mousePosition); if (Physics.Raycast(ray, out hit)) { Vector3 upVectBefore = transform.up; Vector3 forwardVectBefore = transform.forward; Quaternion rotationVectBefore = transform.rotation; Vector3 hitPosition = hit.transform.position; transform.position = hitPosition; float lookDifference = Vector3.Distance(hit.transform.up, forwardVectBefore); if(Vector3.Distance(hit.transform.up, upVectBefore) < .23) //Same normal { transform.rotation = rotationVectBefore; } else if(lookDifference > 1.412 && lookDifference <= 1.70607) //side wall { transform.up = hit.transform.up; transform.forward = forwardVectBefore; } else //head on wall { transform.up = hit.transform.up; transform.forward = upVectBefore; } } } } The first case "Same normal" works fine, however the other two do not work as I would like them to. Sometimes my character is laying down on the surface or on the wrong side of the surface. Does anyone know nice way of solving this problem?

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• Realistic Jumping

  - by Seth Taddiken

  I want to make the jumping that my character does more realistic. This is what I've tried so far but it doesn't seem very realistic when the player jumps. I want it to jump up at a certain speed then slow down as it gets to the top then eventually stopping (for about one frame) and then slowly going back down but going faster and faster as it goes back down. I've been trying to make the speed at which the player jumps up slow down by one each frame then become negative and go down faster... but it doesn't work very well public bool isPlayerDown = true; public bool maxJumpLimit = false; public bool gravityReality = false; public bool leftWall = false; public bool rightWall = false; public float x = 76f; public float y = 405f; if (Keyboard.GetState().IsKeyDown(up) && this.isPlayerDown == true && this.y <= 405f) { this.isPlayerDown = false; } if (this.isPlayerDown == false && this.maxJumpLimit == false) { this.y = this.y - 6; } if (this.y <= 200) { this.maxJumpLimit = true; } if (this.isPlayerDown == true) { this.y = 405f; this.isPlayerDown = true; this.maxJumpLimit = false; } if (this.gravityReality == true) { this.y = this.y + 2f; this.gravityReality = false; } if (this.maxJumpLimit == true) { this.y = this.y + 2f; this.gravityReality = true; } if (this.y > 405f) { this.isPlayerDown = true; }

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• Weird bug in Visual Studio 11 Beta when running on Windows 8

  - by raccoon_tim

  With the Windows 8 Consumer Preview version out in the open and the Visual Studio 11 Beta also available, I’ve been putting some more effort into trying them both out. The first impression of the new Visual Studio 11 build was: Why doesn’t it work at all on Windows 8?! The issues I encountered were odd to say the least. Visual Studio did install correctly, which was a good sign, but when I started it, I was greeted with a multitude of popups each telling me that some package could not be loaded. So I clicked away for quite some time to finally be greeted by the new default visual style of Visual Studio. The next thing I wanted to do was start a new project so I pressed “New Project” and got the “Microsoft.VisualStudio.Dialogs.DialogInitializationException” exception. After some pondering and even submitting a bug report I found another already reported bug “http://connect.microsoft.com/VisualStudio/feedback/details/727578/vs-do-not-work-with-finnish-number-format-on-w8-64-bit”. It turns out that the dialog initialization failure has something to do with the packages no being loaded and following the presented workaround helped. The trick is to change the negative number sign to “-“ (U+002D) from the additional settings of your regional settings. This issue appears to have a wider reach than just Visual Studio as I heard at TechDays Finland 2012 that the same fix has to be made when using Hyper-V.

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• How do I get a different type of scrollbars in 12.04? [closed]

  - by Joseph Garvin

  Possible Duplicate: How do I disable overlay scrollbars? By default 12.04 uses overlay scroll bars that do not suit my taste, and every method I've found so far of disabling them makes them broken in a different way. When I was using 11.10 this wasn't a problem because I could still change the GTK theme. In 12.04, the Appearance settings only contain a few stock themes, and other than the special purpose contrast ones they all have the overlay scroll bars. If I aptitude search gtk3 | grep theme I get no results so there appears to be no packaged alternative either. Most suggestions I've seen for disabling the overlay scroll bars involve uninstalling packages or editing files as root. I want to disable them just for the current user, not for everyone on the whole box; as should be the case for any theme/display setting. There is a gsettings command that temporarily disables the overlay scrollbars just for the current user, but this has two problems of its own: The setting doesn't stick after log off. Because who would want to save settings? The scroll bars put in place have no contrast. They have a black scroller on a black background and are completely unusable. In short what I'd like to know is how to disable overlay scroll bars such that: My preference is user specific. My preference is actually saved. The scroller can actually be seen against the background without having to use a special high contrast theme that makes my whole desktop look like a negative photo from Tron.

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• Long 'Wait' Time for three php/CSS files. Is something blocking them?

  - by William Pitcher

  I have been speed optimizing a Wordpress site to little effect. There are three files CSS-related php files from the Wordpress theme that are delaying page loads on the site. One of the three files is basically one line of custom CSS from the custom CSS feature in the theme. You can see what I am talking about with this Pingdom speed test: The yellow is 'Wait'. There are no slow items in the cut-off portion of the image. The full results are here: Pingdom Results Page 1. Any thoughts on what might be causing this? I understand that I have blocking CSS or JS files, but I don't see anything that would be causing that long of a wait. When I ran the P3 Plugin Profiler, Wordpress and all plugins appeared fine -- it is the theme that is taking all the time. GTmetrix recommends avoiding dynamic queries. I assume all the ver=3.61 references are to the version of Wordpress (which I am using). I noticed that my Wordpress sites using other themes don't make this query (at least not over and over). 2. Is this typical coding practice? 3. How much negative impact do these query-strings have -- a little or a lot? I tried searching for similar questions here, please excuse me if I missed something. Sometimes, I know just enough to be dangerous.

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• can I achieve my dreams without a degree? [closed]

  - by Dhananjay

  It's really giving me a lot stress as my parents saying me to join college but I don't want. I know I can learn all programming by self studying but they keep saying join college otherwise no one will give you job. I always think positive but sometimes I also start thinking like them (what if my life will be spoiled if I do not go to college) There are so much things on internet. I can learn c++, objective c, java, AI, html, php all through internet (at least I think that I can learn whole by self studying and I can give 10 hour/day easily for studying) and I will keep practicing and become a good programmer in 2 years and then try to do some job for experience so no need to waste 4 years just for studying things which I can learn in 2 years and no need to waste money on college because they teach physics, chemistry all in first 2 years and I only want to study comp. Science. But now again I am thinking negative that what will happen if I do not get degree and what will I do after learning programming if I don't get job? Please suggest what should I do? Should I join college? or self study? Can I achieve my dreams without a degree if I study hard and learn many things? I have full confidence that I can self teach myself better than they will teach in college. I will open my app company and many more. But maybe I am over confident because I don't know what happens in real world. How they treat a person without degree, etc. Anyone of you had gone through this condition? What did you do?

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• How to deal with elimination of duplicate logic vs. cost of complexity increase?

  - by Gabriel

  I just wrote some code that is very representative of a recurring theme (in my coding world lately): repeated logic leads to an instinct to eliminate duplication which results in something that is more complex the tradeoff seems wrong to me (the examples of the negative side aren't worth posting - but this is probably the 20th console utility I've written in the past 12 months). I'm curious if I'm missing some techniques or if this is really just on of those "experience tells you when to do what" type of issues. Here's the code... I'm tempted to leave it as is, even though there will be about 20 of those if-blocks when I'm done. static void Main(string[] sargs) { try { var urls = new DirectTrackRestUrls(); var restCall = new DirectTrackRestCall(); var logger = new ConsoleLogger(); Args args = (Args)Enum.Parse(typeof(Args), string.Join(",", sargs)); if (args.HasFlag(Args.Campaigns)) { var getter = new ResourceGetter(logger, urls.ListAdvertisers, restCall); restCall.UriVariables.Add("access_id", 1); getter.GotResource += new ResourceGetter.GotResourceEventHandler(getter_GotResource); getter.GetResources(); SaveResources(); } if (args.HasFlag(Args.Advertisers)) { var getter = new ResourceGetter(logger, urls.ListAdvertisers, restCall); restCall.UriVariables.Add("access_id", 1); getter.GotResource += new ResourceGetter.GotResourceEventHandler(getter_GotResource); getter.GetResources(); SaveResources(); } if (args.HasFlag(Args.CampaignGroups)) { var getter = new ResourceGetter(logger, urls.ListCampaignGroups, restCall); getter.GotResource += new ResourceGetter.GotResourceEventHandler(getter_GotResource); getter.GetResources(); SaveResources(); } } catch (Exception e) { Console.WriteLine(e.InnerException); Console.WriteLine(e.StackTrace); }

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• Reflection velocity

  - by MindSeeker

  I'm trying to get a moving circular object to bounce (elastically) off of an immovable circular object. Am I doing this right? (The results look right, but I hate to trust that alone, and I can't find a tutorial that tackles this problem and includes the nitty gritty math/code to verify what I'm doing). If it is right, is there a better/faster/more elegant way to do this? Note that the object (this) is the moving circle, and the EntPointer object is the immovable circle. //take vector separating the two centers <x, y>, and then get unit vector of the result: MathVector2d unitnormal = MathVector2d(this -> Retxpos() - EntPointer -> Retxpos(), this -> Retypos() - EntPointer -> Retypos()).UnitVector(); //take tangent <-y, x> of the unitnormal: MathVector2d unittangent = MathVector2d(-unitnormal.ycomp, unitnormal.xcomp); MathVector2d V1 = MathVector2d(this -> Retxvel(), this -> Retyvel()); //Calculate the normal and tangent vector lengths of the velocity: (the normal changes, the tangent stays the same) double LengthNormal = DotProduct(unitnormal, V1); double LengthTangent = DotProduct(unittangent, V1); MathVector2d VelVecNewNormal = unitnormal.ScalarMultiplication(-LengthNormal); //the negative of what it was before MathVector2d VelVecNewTangent = unittangent.ScalarMultiplication(LengthTangent); //this stays the same MathVector2d NewVel = VectorAddition(VelVecNewNormal, VelVecNewTangent); //combine them xvel = NewVel.xcomp; //and then apply them yvel = NewVel.ycomp; Note also that this question is just about velocity, the position code is handled elsewhere (in other words, assume that this code is implemented at the exact moment that the circles begin to overlap). Thanks in advance for your help and time!

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• Is SEO affected negatively by having densely encoded identifiers of content in URLs?

  - by casperOne

  This isn't about where to put the id of a piece of unique content in URLs, but more about densely packing the URL (or, does it just not matter). Take for example, a hypothetical post in a blog: http://tempuri.org/123456789/seo-friendly-title The ID that uniquely identifies this is 123456789. This corresponds to a look-up and is the direct key in the underlying data store. However, I could encode that in say, hexadecimal, like so: http://tempuri.org/75bcd15/seo-friendly-title And that would be shorter. One could take it even further and have more compact encodings; since URLs are case sensitive, one could imagine an encoding that uses numbers, lowercase and uppercase letters, for a base of 62 (26 upper case + 26 lower case + 10 digits): 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz For a resulting URL of: http://tempuri.org/8M0kX/seo-friendly-title The question is, does densely packing the ID of the content (the requirement is that an ID is mandatory for look-ups) have a negative impact on SEO (and dare I ask, might it have any positive impact), or is it just not worth the time? Note that this is not for a URL shortening service, so saving space in the URL for browser limitation purposes is not an issue.

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• Is there a formula for this?

  - by Gortron

  TL/DR: Any way to work out if known numbers between a known start and ending figure should be positive or negative numbers? I am developing an application in PHP which can import and read PDFs. The PDFs are financial ones such as bank statements with records of transactions in and out of a bank account. I only have PDFs to work with, no other formats such as CSV unfortunately. I convert the PDF to HTML using pdftohtml and start parsing the data, the intended end result is an array of transactions. So far I have it working smoothly collecting dates, descriptions and balance. Converting the XML instead doesn't help. There are other pieces of transcriptional data such as debit or credit amounts. In the PDF, the credit amount is in one column and the debit amount is in another column so it is quite clear in the PDF. However, when converted to HTML, the formatting is lost and therefor I don't know if the amount was a credit or debit amount. So, my question is, given a starting balance and an ending balance and several known figures in between, is it possible for a programme to work out if those known figures in between are credit or debit amounts? I imagine there could potentially be several combinations of those known values to reach the ending balance so I'd like to apply a formula to return the correct credit/debit sequence only if its the only possible solution. If there are several ways of adding/subtracting the known values to reach the end balance, I can ask the user to look at it manually but I'd like to keep this to a minimum if possible. Possible to do, do you think? Thank you in advance for any help.

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• Leaving my ongoing internship for a better company

  - by AnonymousAsExpected

  Hi. I am currently employed as an intern with a software company X. I had no particular interest in working on their line of work, but since I had no other alternative, I had to join it. I had also applied to a good company Y, which has a better name than X and the work is exactly what I wanted. More than anything, the mention of Y on my resume will make a big difference later. I really had no idea that Y would accept me, since they were not replying to my repeated requests to inform me of the status of my application. Now fifteen days into my internship with X, Y sent me an offer letter to join. What should I do now? There are other interns working with X on the same project I was, and so of course the work won't suffer. My problem is, I want to quit X, but how do I do it in the most polite way possible? I am afraid to ask my boss, he is rude already and I fear he might take it badly. And how do I handle this in my resume? If two years down the line someone asks me why I left X for Y, won't that look bad? I am really confused, working with Y would be like a dream come true. But I fear the negative impact of leaving X. Hoping that someone can perhaps share a similar experience.

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• What packages are safe to uninstall to reduce installation size?

  - by mathematician1975

  This question is similar to a previous question I asked How can I turn my desktop Ubuntu 8.04 into a command line only install?. I was wondering if anyone can recommend any other bulky packages from the standard 8.04 installation that can reduce the size on disk of my installation. All I really require is socket functionality, g++ and gcc, some kind of text editor and SSH client and server. Things that I don't require are things like media players, audio packages, and the more "superficial" kind of desktop niceties. Is there anything particularly large in a standard install that is safe for me to remove without compromising my requirements above? I am a bit apprehensive about trying to uninstall items and I am not totally confident about removal of particular things having a negative effect on the functionality of any other things I might need (an example is would it be safe for me to remove everything to do with Perl, or does the system/kernel/other processes require this) ??? Basically I would like to be left with the kind of items that would have been installed in the CLI version of 8.04 (had the alternative iso image not been faulty). Any help/suggestions would be gratefully received.

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• How to stop reducing life? [closed]

  - by SystemNetworks

  CODE Input input = gc.getInput(); int xpos = Mouse.getX(); int ypos = Mouse.getY(); emu = "Enemy Life : " + enemyLife; Life = "Your Life Is" + life; Mousepos = "X:" + xpos + "Y:" + ypos; //test test1 = "Test INT" + test1int; if(!repeatStop) { //if this button is press, the damage will add up. When //pressed fight, it would start reducing the enemy health. if(input.isKeyPressed(Input.KEY_1)) { test1int += 1; } } if((xpos>1007 &xpos<1297)&&(ypos>881 && ypos<971)) { //Fight button if(Mouse.isButtonDown(0)){ finishTurn=true; } } //fight has started if(finishTurn==true) { //this would reduce the enemy life if(floodControl1==false) { enemyLife-=test1int; } //PROBLEM: Does not stop reducing! //the below code was not successful. It did not stop it // from reducing further. if(test1int>10) { floodControl1=true; } } QUESTION: Ok now, this is what is does. When I press the key, 1, it adds up the damage to the enemy. When I press fight, It will then start to reduce the enemy's health. Now my problem is, it kept on reducing and deducting it until negative! How do I deduct it to my desired damage (My desired damage is the one when press key 1)?

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• What do ptLineDist and relativeCCW do?

  - by Fasih Khatib

  I saw these methods in the Line2D Java Docs but did not understand what they do? Javadoc for ptLineDist says: Returns the distance from a point to this line. The distance measured is the distance between the specified point and the closest point on the infinitely-extended line defined by this Line2D. If the specified point intersects the line, this method returns 0.0 Doc for relativeCCW says: Returns an indicator of where the specified point (PX, PY) lies with respect to the line segment from (X1, Y1) to (X2, Y2). The return value can be either 1, -1, or 0 and indicates in which direction the specified line must pivot around its first endpoint, (X1, Y1), in order to point at the specified point (PX, PY). A return value of 1 indicates that the line segment must turn in the direction that takes the positive X axis towards the negative Y axis. In the default coordinate system used by Java 2D, this direction is counterclockwise. A return value of -1 indicates that the line segment must turn in the direction that takes the positive X axis towards the positive Y axis. In the default coordinate system, this direction is clockwise. A return value of 0 indicates that the point lies exactly on the line segment. Note that an indicator value of 0 is rare and not useful for determining colinearity because of floating point rounding issues. If the point is colinear with the line segment, but not between the endpoints, then the value will be -1 if the point lies "beyond (X1, Y1)" or 1 if the point lies "beyond (X2, Y2)".

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• Hard drive clicking noise on Acer AO722

  - by Blank

  I'm running Ubuntu 11.10 on an Acer Aspire One 722. Whenever I'm on battery power I get a clicking sound from my hard drive every 5 seconds or so (this does not happen when the laptop is plugged in). I'm dual booting with Windows 7 and I don't get the clicking sound in Windows. The clicking sound stops when I run the command:sudo hdparm -B 254 /dev/sda Also, according to:sudo smartctl -H /dev/sda my hard drive is healthy. Is this clicking sound something I can just ignore? Or is it a serious problem and will it eventually damage my computer? If so, how would I fix it? I have tried adding hdparm -B 254 /dev/sda to my /etc/rc.local file, but I still run into the clicking problem if my computer boots while plugged in and is then unplugged. Also, I'm finding this fix to be unreliable. Sometimes it works, sometimes it does not. Is this a good solution and is there a better way of doing this? Also, would running my laptop with a -B value of 254 have any negative effects? (I read somewhere about a lower level protecting the hard drive from bumps)

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• loading a heightmap as texture in shader

  - by wtherapy

  I have a height map of 256x256, containing, foreach cell, not only height as a normal float value ( not 0-1 ) and also 2 gradient values ( for X and Y ), also as normal float values ( not 0-1 ). I have uploaded the texture via normal texture loading: glEnable( GL_TEXTURE_2D ); glGenTextures( 1, &m_uglID ); DEBUG_OUTPUT("Err %x\n", glGetError()); glBindTexture( GL_TEXTURE_2D , m_uglID ); DEBUG_OUTPUT("Err %x\n", glGetError()); glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB32F, unW + 1, unH + 1, 0, GL_RGB, GL_FLOAT, pvBytes ); DEBUG_OUTPUT("Err %x\n", glGetError()); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_LINEAR); DEBUG_OUTPUT("Err %x\n", glGetError()); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_LINEAR); DEBUG_OUTPUT("Err %x\n", glGetError()); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); DEBUG_OUTPUT("Err %x\n", glGetError()); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); DEBUG_OUTPUT("Err %x\n", glGetError()); as a parenthesis, the debug output is: Err 500 Err 0 Err 0 Err 0 Err 500 Err 500 Err 0 Err 0 pvBytes is a 256x256 array of typedef struct _tGradientHeightCell { float v; float px; float py; } TGradientHeightCell, *LPTGradientHeightCell; then, m_ugl_HeightMapTexture = glGetUniformLocation(m_uglProgram, "TexHeightMap"); I load it via: glEnable(GL_TEXTURE_2D ); glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D , pTexture->GetID()); glUniform1i(m_ugl_HeightMapTexture, 0); in shader, I just access it: uniform sampler2D TexHeightMap; vec4 GetVertCellParameters( uint i, uint j ) { return texture( TexHeightMap, vec2( i, j ) ); } vec4 vH00 = GetVertCellParameters( i, j ); My problem is that, when passing negative values in one of the values in TGradientHeightCell ( v, px, py ), the texture is corrupted. I need the values to be passed exact as I have them in memory. Any help appreciated.

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• How to persuade C fanatics to work on my C++ open source project?

  - by paperjam

  I am launching an open-source project into a space where a lot of the development is still done Linux-kernel-style, i.e. C-language with a low-level mindset. There are multiple benefits to C++ in our space but I fear those used to working in C will be scared off. How can I make the case for the benefits of C++? Specifically, the following C++ attributes are very valuable: concept of objects and reference-counting pointers - really don't want to have to malloc(sizeof(X)) or memcpy() structs templates for specialising whole bodies of code with specific performance optimizations and for avoiding duplication of code. template metaprogramming related to the above syntactic sweetness available (e.g. operator overloading, to be used in very small doses) STL Boost libraries Many of the knee-jerk negative reactions to C++ are illfounded. Performance does not suffer: modern compilers can flatten dozens of call stack levels and avoid bloat through wide use of template specializations. Granted, when using metaprogramming and building multiple specializations of a large call tree, compile time is slower but there are ways to mitigate this. How can I sell C++?

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• Transforms in Box2D

  - by user1264811

  I'm attempting to implement a camera in my game. I had it working for regular objects, but I began using Box2D and obviously things changed a bit. I have a Body object that I want to draw at the center of the screen. Basically what I'm doing is subtracting the viewportX and viewportY to the Body. I use this code that currently is not working as it should: public void paint(Graphics2D g, int viewportX, int viewportY) { Transform xf = new Transform(); // m_body is the Body object xf.set(m_body.getTransform()); // Here what I attemp to do is take the transform and alter it // by the viewportX and Y, which is something like **-240, -150**. // Why is it negative? Because an object has coordinates 500, 300 would be displayed // at 160, 150 when the subtraction is done. // With the DrawUtils.toScale(), it's just how I convert the units from JBox2D units // to my units. Vec2 v = Transform.mulTrans(xf, new Vec2(DrawUtils.toScale(-viewportX), DrawUtils.toScale(-viewportY))); // Set the new transform to the new vector. Keep the old angle. xf.set(v, xf.q.getAngle()); g.setColor(Color.white); // I know for a fact that the following method works 100%. It correctly displays // my object, just that it doesn't follow it. for (Fixture f = m_body.getFixtureList(); f != null; f = f.getNext()) DrawUtils.drawShape(f, xf); } Hopefully I didn't over comment this and you understand my problem. I don't want to alter the actual physics position of the object, I just want to display it in the center.

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• Can an Employer turn you down if you have said the fact about current work culture being bad [closed]

  - by MansonRix

  I had recently an interview where I scored good in 1st two round of technical interview . Then in the 3rd round was the managerial round where the guy started about my experience and whether I have vaptured any requirement and handled and trained any teams. This went pretty well for around 50 mins . Then there was the awkward question , Interviewer: why amI looking for a change? Me: coz I want to explore my carrier options? Interviewer: But your current company is big enough and you can explore options over there? (This was supposedly the trap) Me: Apart from that I am missing the flexibilty of working with Us and Europe based company as my current company is not that flexible. Interviewer: What exactly you don't find flexible. Me: The login time . Even if you get late by 1sec you might have to explin. Though this is not a big problem , still I will prefer flexibilty as we are working really hard. Interviewer: Allright ( Then couple of more questions) , Hope to C U Ya , that's pretty much it . Now I called up HR and they say , they are yet to get the feedback from Interviewer. Did I screw it? I mean does some one really have to pretend always by saying positive things about company and manager though not saying negative things?

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• Sensible Way to Pass Web Data in XML to a SQL Server Database

  - by Emtucifor

  After exploring several different ways to pass web data to a database for update purposes, I'm wondering if XML might be a good strategy. The database is currently SQL 2000. In a few months it will move to SQL 2005 and I will be able to change things if needed, but I need a SQL 2000 solution now. First of all, the database in question uses the EAV model. I know that this kind of database is generally highly frowned on, so for the purposes of this question, please just accept that this is not going to change. The current update method has the web server inserting values (that have all been converted first to their correct underlying types, then to sql_variant) to a temp table. A stored procedure is then run which expects the temp table to exist and it takes care of updating, inserting, or deleting things as needed. So far, only a single element has needed to be updated at a time. But now, there is a requirement to be able to edit multiple elements at once, and also to support hierarchical elements, each of which can have its own list of attributes. Here's some example XML I hand-typed to demonstrate what I'm thinking of. Note that in this database the Entity is Element and an ID of 0 signifies "create" aka an insert of a new item. <Elements> <Element ID="1234"> <Attr ID="221">Value</Attr> <Attr ID="225">287</Attr> <Attr ID="234"> <Element ID="99825"> <Attr ID="7">Value1</Attr> <Attr ID="8">Value2</Attr> <Attr ID="9" Action="delete" /> </Element> <Element ID="99826" Action="delete" /> <Element ID="0" Type="24"> <Attr ID="7">Value4</Attr> <Attr ID="8">Value5</Attr> <Attr ID="9">Value6</Attr> </Element> <Element ID="0" Type="24"> <Attr ID="7">Value7</Attr> <Attr ID="8">Value8</Attr> <Attr ID="9">Value9</Attr> </Element> </Attr> <Rel ID="3827" Action="delete" /> <Rel ID="2284" Role="parent"> <Element ID="3827" /> <Element ID="3829" /> <Attr ID="665">1</Attr> </Rel> <Rel ID="0" Type="23" Role="child"> <Element ID="3830" /> <Attr ID="67" </Rel> </Element> <Element ID="0" Type="87"> <Attr ID="221">Value</Attr> <Attr ID="225">569</Attr> <Attr ID="234"> <Element ID="0" Type="24"> <Attr ID="7">Value10</Attr> <Attr ID="8">Value11</Attr> <Attr ID="9">Value12</Attr> </Element> </Attr> </Element> <Element ID="1235" Action="delete" /> </Elements> Some Attributes are straight value types, such as AttrID 221. But AttrID 234 is a special "multi-value" type that can have a list of elements underneath it, and each one can have one or more values. Types only need to be presented when a new item is created, since the ElementID fully implies the type if it already exists. I'll probably support only passing in changed items (as detected by javascript). And there may be an Action="Delete" on Attr elements as well, since NULLs are treated as "unselected"--sometimes it's very important to know if a Yes/No question has intentionally been answered No or if no one's bothered to say Yes yet. There is also a different kind of data, a Relationship. At this time, those are updated through individual AJAX calls as things are edited in the UI, but I'd like to include those so that changes to relationships can be canceled (right now, once you change it, it's done). So those are really elements, too, but they are called Rel instead of Element. Relationships are implemented as ElementID1 and ElementID2, so the RelID 2284 in the XML above is in the database as: ElementID 2284 ElementID1 1234 ElementID2 3827 Having multiple children in one relationship isn't currently supported, but it would be nice later. Does this strategy and the example XML make sense? Is there a more sensible way? I'm just looking for some broad critique to help save me from going down a bad path. Any aspect that you'd like to comment on would be helpful. The web language happens to be Classic ASP, but that could change to ASP.Net at some point. A persistence engine like Linq or nHibernate is probably not acceptable right now--I just want to get this already working application enhanced without a huge amount of development time. I'll choose the answer that shows experience and has a balance of good warnings about what not to do, confirmations of what I'm planning to do, and recommendations about something else to do. I'll make it as objective as possible. P.S. I'd like to handle unicode characters as well as very long strings (10k +). UPDATE I have had this working for some time and I used the ADO Recordset Save-To-Stream trick to make creating the XML really easy. The result seems to be fairly fast, though if speed ever becomes a problem I may revisit this. In the meantime, my code works to handle any number of elements and attributes on the page at once, including updating, deleting, and creating new items all in one go. I settled on a scheme like so for all my elements: Existing data elements Example: input name e12345_a678 (element 12345, attribute 678), the input value is the value of the attribute. New elements Javascript copies a hidden template of the set of HTML elements needed for the type into the correct location on the page, increments a counter to get a new ID for this item, and prepends the number to the names of the form items. var newid = 0; function metadataAdd(reference, nameid, value) { var t = document.createElement('input'); t.setAttribute('name', nameid); t.setAttribute('id', nameid); t.setAttribute('type', 'hidden'); t.setAttribute('value', value); reference.appendChild(t); } function multiAdd(target, parentelementid, attrid, elementtypeid) { var proto = document.getElementById('a' + attrid + '_proto'); var instance = document.createElement('p'); target.parentNode.parentNode.insertBefore(instance, target.parentNode); var thisid = ++newid; instance.innerHTML = proto.innerHTML.replace(/{prefix}/g, 'n' + thisid + '_'); instance.id = 'n' + thisid; instance.className += ' new'; metadataAdd(instance, 'n' + thisid + '_p', parentelementid); metadataAdd(instance, 'n' + thisid + '_c', attrid); metadataAdd(instance, 'n' + thisid + '_t', elementtypeid); return false; } Example: Template input name _a678 becomes n1_a678 (a new element, the first one on the page, attribute 678). all attributes of this new element are tagged with the same prefix of n1. The next new item will be n2, and so on. Some hidden form inputs are created: n1_t, value is the elementtype of the element to be created n1_p, value is the parent id of the element (if it is a relationship) n1_c, value is the child id of the element (if it is a relationship) Deleting elements A hidden input is created in the form e12345_t with value set to 0. The existing controls displaying that attribute's values are disabled so they are not included in the form post. So "set type to 0" is treated as delete. With this scheme, every item on the page has a unique name and can be distinguished properly, and every action can be represented properly. When the form is posted, here's a sample of building one of the two recordsets used (classic ASP code): Set Data = Server.CreateObject("ADODB.Recordset") Data.Fields.Append "ElementID", adInteger, 4, adFldKeyColumn Data.Fields.Append "AttrID", adInteger, 4, adFldKeyColumn Data.Fields.Append "Value", adLongVarWChar, 2147483647, adFldIsNullable Or adFldMayBeNull Data.CursorLocation = adUseClient Data.CursorType = adOpenDynamic Data.Open This is the recordset for values, the other is for the elements themselves. I step through the posted form and for the element recordset use a Scripting.Dictionary populated with instances of a custom Class that has the properties I need, so that I can add the values piecemeal, since they don't always come in order. New elements are added as negative to distinguish them from regular elements (rather than requiring a separate column to indicate if it is new or addresses an existing element). I use regular expression to tear apart the form keys: "^(e|n)([0-9]{1,10})_(a|p|t|c)([0-9]{0,10})$" Then, adding an attribute looks like this. Data.AddNew ElementID.Value = DataID AttrID.Value = Integerize(Matches(0).SubMatches(3)) AttrValue.Value = Request.Form(Key) Data.Update ElementID, AttrID, and AttrValue are references to the fields of the recordset. This method is hugely faster than using Data.Fields("ElementID").Value each time. I loop through the Dictionary of element updates and ignore any that don't have all the proper information, adding the good ones to the recordset. Then I call my data-updating stored procedure like so: Set Cmd = Server.CreateObject("ADODB.Command") With Cmd Set .ActiveConnection = MyDBConn .CommandType = adCmdStoredProc .CommandText = "DataPost" .Prepared = False .Parameters.Append .CreateParameter("@ElementMetadata", adLongVarWChar, adParamInput, 2147483647, XMLFromRecordset(Element)) .Parameters.Append .CreateParameter("@ElementData", adLongVarWChar, adParamInput, 2147483647, XMLFromRecordset(Data)) End With Result.Open Cmd ' previously created recordset object with options set Here's the function that does the xml conversion: Private Function XMLFromRecordset(Recordset) Dim Stream Set Stream = Server.CreateObject("ADODB.Stream") Stream.Open Recordset.Save Stream, adPersistXML Stream.Position = 0 XMLFromRecordset = Stream.ReadText End Function Just in case the web page needs to know, the SP returns a recordset of any new elements, showing their page value and their created value (so I can see that n1 is now e12346 for example). Here are some key snippets from the stored procedure. Note this is SQL 2000 for now, though I'll be able to switch to 2005 soon: CREATE PROCEDURE [dbo].[DataPost] @ElementMetaData ntext, @ElementData ntext AS DECLARE @hdoc int --- snip --- EXEC sp_xml_preparedocument @hdoc OUTPUT, @ElementMetaData, '<xml xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" />' INSERT #ElementMetadata (ElementID, ElementTypeID, ElementID1, ElementID2) SELECT * FROM OPENXML(@hdoc, '/xml/rs:data/rs:insert/z:row', 0) WITH ( ElementID int, ElementTypeID int, ElementID1 int, ElementID2 int ) ORDER BY ElementID -- orders negative items (new elements) first so they begin counting at 1 for later ID calculation EXEC sp_xml_removedocument @hdoc --- snip --- UPDATE E SET E.ElementTypeID = M.ElementTypeID FROM Element E INNER JOIN #ElementMetadata M ON E.ElementID = M.ElementID WHERE E.ElementID >= 1 AND M.ElementTypeID >= 1 The following query does the correlation of the negative new element ids to the newly inserted ones: UPDATE #ElementMetadata -- Correlate the new ElementIDs with the input rows SET NewElementID = Scope_Identity() - @@RowCount + DataID WHERE ElementID < 0 Other set-based queries do all the other work of validating that the attributes are allowed, are the correct data type, and inserting, updating, and deleting elements and attributes. I hope this brief run-down is useful to others some day! Converting ADO Recordsets to an XML stream was a huge winner for me as it saved all sorts of time and had a namespace and schema already defined that made the results come out correctly. Using a flatter XML format with 2 inputs was also much easier than sticking to some ideal about having everything in a single XML stream.

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• Sensible Way to Pass Web Data to Sql Server Database

  - by Emtucifor

  After exploring several different ways to pass web data to a database for update purposes, I'm wondering if XML might be a good strategy. The database is currently SQL 2000. In a few months it will move to SQL 2005 and I will be able to change things if needed, but I need a SQL 2000 solution now. First of all, the database in question uses the EAV model. I know that this kind of database is generally highly frowned on, so for the purposes of this question, please just accept that this is not going to change. The current update method has the web server inserting values (that have all been converted first to their correct underlying types, then to sql_variant) to a temp table. A stored procedure is then run which expects the temp table to exist and it takes care of updating, inserting, or deleting things as needed. So far, only a single element has needed to be updated at a time. But now, there is a requirement to be able to edit multiple elements at once, and also to support hierarchical elements, each of which can have its own list of attributes. Here's some example XML I hand-typed to demonstrate what I'm thinking of. Note that in this database the Entity is Element and an ID of 0 signifies "create" aka an insert of a new item. <Elements> <Element ID="1234"> <Attr ID="221">Value</Attr> <Attr ID="225">287</Attr> <Attr ID="234"> <Element ID="99825"> <Attr ID="7">Value1</Attr> <Attr ID="8">Value2</Attr> <Attr ID="9" Action="delete" /> </Element> <Element ID="99826" Action="delete" /> <Element ID="0" Type="24"> <Attr ID="7">Value4</Attr> <Attr ID="8">Value5</Attr> <Attr ID="9">Value6</Attr> </Element> <Element ID="0" Type="24"> <Attr ID="7">Value7</Attr> <Attr ID="8">Value8</Attr> <Attr ID="9">Value9</Attr> </Element> </Attr> <Rel ID="3827" Action="delete" /> <Rel ID="2284" Role="parent"> <Element ID="3827" /> <Element ID="3829" /> <Attr ID="665">1</Attr> </Rel> <Rel ID="0" Type="23" Role="child"> <Element ID="3830" /> <Attr ID="67" </Rel> </Element> <Element ID="0" Type="87"> <Attr ID="221">Value</Attr> <Attr ID="225">569</Attr> <Attr ID="234"> <Element ID="0" Type="24"> <Attr ID="7">Value10</Attr> <Attr ID="8">Value11</Attr> <Attr ID="9">Value12</Attr> </Element> </Attr> </Element> <Element ID="1235" Action="delete" /> </Elements> Some Attributes are straight value types, such as AttrID 221. But AttrID 234 is a special "multi-value" type that can have a list of elements underneath it, and each one can have one or more values. Types only need to be presented when a new item is created, since the ElementID fully implies the type if it already exists. I'll probably support only passing in changed items (as detected by javascript). And there may be an Action="Delete" on Attr elements as well, since NULLs are treated as "unselected"--sometimes it's very important to know if a Yes/No question has intentionally been answered No or if no one's bothered to say Yes yet. There is also a different kind of data, a Relationship. At this time, those are updated through individual AJAX calls as things are edited in the UI, but I'd like to include those so that changes to relationships can be canceled (right now, once you change it, it's done). So those are really elements, too, but they are called Rel instead of Element. Relationships are implemented as ElementID1 and ElementID2, so the RelID 2284 in the XML above is in the database as: ElementID 2284 ElementID1 1234 ElementID2 3827 Having multiple children in one relationship isn't currently supported, but it would be nice later. Does this strategy and the example XML make sense? Is there a more sensible way? I'm just looking for some broad critique to help save me from going down a bad path. Any aspect that you'd like to comment on would be helpful. The web language happens to be Classic ASP, but that could change to ASP.Net at some point. A persistence engine like Linq or nHibernate is probably not acceptable right now--I just want to get this already working application enhanced without a huge amount of development time. I'll choose the answer that shows experience and has a balance of good warnings about what not to do, confirmations of what I'm planning to do, and recommendations about something else to do. I'll make it as objective as possible. P.S. I'd like to handle unicode characters as well as very long strings (10k +). UPDATE I have had this working for some time and I used the ADO Recordset Save-To-Stream trick to make creating the XML really easy. The result seems to be fairly fast, though if speed ever becomes a problem I may revisit this. In the meantime, my code works to handle any number of elements and attributes on the page at once, including updating, deleting, and creating new items all in one go. I settled on a scheme like so for all my elements: Existing data elements Example: input name e12345_a678 (element 12345, attribute 678), the input value is the value of the attribute. New elements Javascript copies a hidden template of the set of HTML elements needed for the type into the correct location on the page, increments a counter to get a new ID for this item, and prepends the number to the names of the form items. var newid = 0; function metadataAdd(reference, nameid, value) { var t = document.createElement('input'); t.setAttribute('name', nameid); t.setAttribute('id', nameid); t.setAttribute('type', 'hidden'); t.setAttribute('value', value); reference.appendChild(t); } function multiAdd(target, parentelementid, attrid, elementtypeid) { var proto = document.getElementById('a' + attrid + '_proto'); var instance = document.createElement('p'); target.parentNode.parentNode.insertBefore(instance, target.parentNode); var thisid = ++newid; instance.innerHTML = proto.innerHTML.replace(/{prefix}/g, 'n' + thisid + '_'); instance.id = 'n' + thisid; instance.className += ' new'; metadataAdd(instance, 'n' + thisid + '_p', parentelementid); metadataAdd(instance, 'n' + thisid + '_c', attrid); metadataAdd(instance, 'n' + thisid + '_t', elementtypeid); return false; } Example: Template input name _a678 becomes n1_a678 (a new element, the first one on the page, attribute 678). all attributes of this new element are tagged with the same prefix of n1. The next new item will be n2, and so on. Some hidden form inputs are created: n1_t, value is the elementtype of the element to be created n1_p, value is the parent id of the element (if it is a relationship) n1_c, value is the child id of the element (if it is a relationship) Deleting elements A hidden input is created in the form e12345_t with value set to 0. The existing controls displaying that attribute's values are disabled so they are not included in the form post. So "set type to 0" is treated as delete. With this scheme, every item on the page has a unique name and can be distinguished properly, and every action can be represented properly. When the form is posted, here's a sample of building one of the two recordsets used (classic ASP code): Set Data = Server.CreateObject("ADODB.Recordset") Data.Fields.Append "ElementID", adInteger, 4, adFldKeyColumn Data.Fields.Append "AttrID", adInteger, 4, adFldKeyColumn Data.Fields.Append "Value", adLongVarWChar, 2147483647, adFldIsNullable Or adFldMayBeNull Data.CursorLocation = adUseClient Data.CursorType = adOpenDynamic Data.Open This is the recordset for values, the other is for the elements themselves. I step through the posted form and for the element recordset use a Scripting.Dictionary populated with instances of a custom Class that has the properties I need, so that I can add the values piecemeal, since they don't always come in order. New elements are added as negative to distinguish them from regular elements (rather than requiring a separate column to indicate if it is new or addresses an existing element). I use regular expression to tear apart the form keys: "^(e|n)([0-9]{1,10})_(a|p|t|c)([0-9]{0,10})$" Then, adding an attribute looks like this. Data.AddNew ElementID.Value = DataID AttrID.Value = Integerize(Matches(0).SubMatches(3)) AttrValue.Value = Request.Form(Key) Data.Update ElementID, AttrID, and AttrValue are references to the fields of the recordset. This method is hugely faster than using Data.Fields("ElementID").Value each time. I loop through the Dictionary of element updates and ignore any that don't have all the proper information, adding the good ones to the recordset. Then I call my data-updating stored procedure like so: Set Cmd = Server.CreateObject("ADODB.Command") With Cmd Set .ActiveConnection = MyDBConn .CommandType = adCmdStoredProc .CommandText = "DataPost" .Prepared = False .Parameters.Append .CreateParameter("@ElementMetadata", adLongVarWChar, adParamInput, 2147483647, XMLFromRecordset(Element)) .Parameters.Append .CreateParameter("@ElementData", adLongVarWChar, adParamInput, 2147483647, XMLFromRecordset(Data)) End With Result.Open Cmd ' previously created recordset object with options set Here's the function that does the xml conversion: Private Function XMLFromRecordset(Recordset) Dim Stream Set Stream = Server.CreateObject("ADODB.Stream") Stream.Open Recordset.Save Stream, adPersistXML Stream.Position = 0 XMLFromRecordset = Stream.ReadText End Function Just in case the web page needs to know, the SP returns a recordset of any new elements, showing their page value and their created value (so I can see that n1 is now e12346 for example). Here are some key snippets from the stored procedure. Note this is SQL 2000 for now, though I'll be able to switch to 2005 soon: CREATE PROCEDURE [dbo].[DataPost] @ElementMetaData ntext, @ElementData ntext AS DECLARE @hdoc int --- snip --- EXEC sp_xml_preparedocument @hdoc OUTPUT, @ElementMetaData, '<xml xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" />' INSERT #ElementMetadata (ElementID, ElementTypeID, ElementID1, ElementID2) SELECT * FROM OPENXML(@hdoc, '/xml/rs:data/rs:insert/z:row', 0) WITH ( ElementID int, ElementTypeID int, ElementID1 int, ElementID2 int ) ORDER BY ElementID -- orders negative items (new elements) first so they begin counting at 1 for later ID calculation EXEC sp_xml_removedocument @hdoc --- snip --- UPDATE E SET E.ElementTypeID = M.ElementTypeID FROM Element E INNER JOIN #ElementMetadata M ON E.ElementID = M.ElementID WHERE E.ElementID >= 1 AND M.ElementTypeID >= 1 The following query does the correlation of the negative new element ids to the newly inserted ones: UPDATE #ElementMetadata -- Correlate the new ElementIDs with the input rows SET NewElementID = Scope_Identity() - @@RowCount + DataID WHERE ElementID < 0 Other set-based queries do all the other work of validating that the attributes are allowed, are the correct data type, and inserting, updating, and deleting elements and attributes. I hope this brief run-down is useful to others some day! Converting ADO Recordsets to an XML stream was a huge winner for me as it saved all sorts of time and had a namespace and schema already defined that made the results come out correctly. Using a flatter XML format with 2 inputs was also much easier than sticking to some ideal about having everything in a single XML stream.

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• FreeBSD performance tuning. Sysctls, loader.conf, kernel

  - by SaveTheRbtz

  I wanted to share knowledge of tuning FreeBSD via sysctl.conf/loader.conf/KENCONF. It was initially based on Igor Sysoev's (author of nginx) presentation about FreeBSD tuning up to 100,000-200,000 active connections. Tunings are for FreeBSD-CURRENT. Since 7.2 amd64 some of them are tuned well by default. Prior 7.0 some of them are boot only (set via /boot/loader.conf) or does not exist at all. sysctl.conf: # No zero mapping feature # May break wine # (There are also reports about broken samba3) #security.bsd.map_at_zero=0 # If you have really busy webserver with apache13 you may run out of processes #kern.maxproc=10000 # Same for servers with apache2 / Pound #kern.threads.max_threads_per_proc=4096 # Max. backlog size kern.ipc.somaxconn=4096 # Shared memory // 7.2+ can use shared memory > 2Gb kern.ipc.shmmax=2147483648 # Sockets kern.ipc.maxsockets=204800 # Can cause this on older kernels: # http://old.nabble.com/Significant-performance-regression-for-increased-maxsockbuf-on-8.0-RELEASE-tt26745981.html#a26745981 ) kern.ipc.maxsockbuf=10485760 # Mbuf 2k clusters (on amd64 7.2+ 25600 is default) # For such high value vm.kmem_size must be increased to 3G kern.ipc.nmbclusters=262144 # Jumbo pagesize(_SC_PAGESIZE) clusters # Used as general packet storage for jumbo frames # can be monitored via `netstat -m` #kern.ipc.nmbjumbop=262144 # Jumbo 9k/16k clusters # If you are using them #kern.ipc.nmbjumbo9=65536 #kern.ipc.nmbjumbo16=32768 # For lower latency you can decrease scheduler's maximum time slice # default: stathz/10 (~ 13) #kern.sched.slice=1 # Increase max command-line length showed in `ps` (e.g for Tomcat/Java) # Default is PAGE_SIZE / 16 or 256 on x86 # This avoids commands to be presented as [executable] in `ps` # For more info see: http://www.freebsd.org/cgi/query-pr.cgi?pr=120749 kern.ps_arg_cache_limit=4096 # Every socket is a file, so increase them kern.maxfiles=204800 kern.maxfilesperproc=200000 kern.maxvnodes=200000 # On some systems HPET is almost 2 times faster than default ACPI-fast # Useful on systems with lots of clock_gettime / gettimeofday calls # See http://old.nabble.com/ACPI-fast-default-timecounter,-but-HPET-83--faster-td23248172.html # After revision 222222 HPET became default: http://svnweb.freebsd.org/base?view=revision&revision=222222 kern.timecounter.hardware=HPET # Small receive space, only usable on http-server, on file server this # should be increased to 65535 or even more #net.inet.tcp.recvspace=8192 # This is useful on Fat-Long-Pipes #net.inet.tcp.recvbuf_max=10485760 #net.inet.tcp.recvbuf_inc=65535 # Small send space is useful for http servers that serve small files # Autotuned since 7.x net.inet.tcp.sendspace=16384 # This is useful on Fat-Long-Pipes #net.inet.tcp.sendbuf_max=10485760 #net.inet.tcp.sendbuf_inc=65535 # Turn off receive autotuning # You can play with it. #net.inet.tcp.recvbuf_auto=0 #net.inet.tcp.sendbuf_auto=0 # This should be enabled if you going to use big spaces (>64k) # Also timestamp field is useful when using syncookies net.inet.tcp.rfc1323=1 # Turn this off on high-speed, lossless connections (LAN 1Gbit+) # If you set it there is no need in TCP_NODELAY sockopt (see man tcp) net.inet.tcp.delayed_ack=0 # This feature is useful if you are serving data over modems, Gigabit Ethernet, # or even high speed WAN links (or any other link with a high bandwidth delay product), # especially if you are also using window scaling or have configured a large send window. # Automatically disables on small RTT ( http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/tcp_subr.c?#rev1.237 ) # This sysctl was removed in 10-CURRENT: # See: http://www.mail-archive.com/[email protected]/msg06178.html #net.inet.tcp.inflight.enable=0 # TCP slowstart algorithm tunings # We assuming we have very fast clients #net.inet.tcp.slowstart_flightsize=100 #net.inet.tcp.local_slowstart_flightsize=100 # Disable randomizing of ports to avoid false RST # Before usage check SA here www.bsdcan.org/2006/papers/ImprovingTCPIP.pdf # (it's also says that port randomization auto-disables at some conn.rates, but I didn't checked it thou) #net.inet.ip.portrange.randomized=0 # Increase portrange # For outgoing connections only. Good for seed-boxes and ftp servers. net.inet.ip.portrange.first=1024 net.inet.ip.portrange.last=65535 # # stops route cache degregation during a high-bandwidth flood # http://www.freebsd.org/doc/en/books/handbook/securing-freebsd.html #net.inet.ip.rtexpire=2 net.inet.ip.rtminexpire=2 net.inet.ip.rtmaxcache=1024 # Security net.inet.ip.redirect=0 net.inet.ip.sourceroute=0 net.inet.ip.accept_sourceroute=0 net.inet.icmp.maskrepl=0 net.inet.icmp.log_redirect=0 net.inet.icmp.drop_redirect=1 net.inet.tcp.drop_synfin=1 # # There is also good example of sysctl.conf with comments: # http://www.thern.org/projects/sysctl.conf # # icmp may NOT rst, helpful for those pesky spoofed # icmp/udp floods that end up taking up your outgoing # bandwidth/ifqueue due to all that outgoing RST traffic. # #net.inet.tcp.icmp_may_rst=0 # Security net.inet.udp.blackhole=1 net.inet.tcp.blackhole=2 # IPv6 Security # For more info see http://www.fosslc.org/drupal/content/security-implications-ipv6 # Disable Node info replies # To see this vulnerability in action run `ping6 -a sglAac ::1` or `ping6 -w ::1` on unprotected node net.inet6.icmp6.nodeinfo=0 # Turn on IPv6 privacy extensions # For more info see proposal http://unix.derkeiler.com/Mailing-Lists/FreeBSD/net/2008-06/msg00103.html net.inet6.ip6.use_tempaddr=1 net.inet6.ip6.prefer_tempaddr=1 # Disable ICMP redirect net.inet6.icmp6.rediraccept=0 # Disable acceptation of RA and auto linklocal generation if you don't use them #net.inet6.ip6.accept_rtadv=0 #net.inet6.ip6.auto_linklocal=0 # Increases default TTL, sometimes useful # Default is 64 net.inet.ip.ttl=128 # Lessen max segment life to conserve resources # ACK waiting time in miliseconds # (default: 30000. RFC from 1979 recommends 120000) net.inet.tcp.msl=5000 # Max bumber of timewait sockets net.inet.tcp.maxtcptw=200000 # Don't use tw on local connections # As of 15 Apr 2009. Igor Sysoev says that nolocaltimewait has some buggy realization. # So disable it or now till get fixed #net.inet.tcp.nolocaltimewait=1 # FIN_WAIT_2 state fast recycle net.inet.tcp.fast_finwait2_recycle=1 # Time before tcp keepalive probe is sent # default is 2 hours (7200000) #net.inet.tcp.keepidle=60000 # Should be increased until net.inet.ip.intr_queue_drops is zero net.inet.ip.intr_queue_maxlen=4096 # Interrupt handling via multiple CPU, but with context switch. # You can play with it. Default is 1; #net.isr.direct=0 # This is for routers only #net.inet.ip.forwarding=1 #net.inet.ip.fastforwarding=1 # This speed ups dummynet when channel isn't saturated net.inet.ip.dummynet.io_fast=1 # Increase dummynet(4) hash #net.inet.ip.dummynet.hash_size=2048 #net.inet.ip.dummynet.max_chain_len # Should be increased when you have A LOT of files on server # (Increase until vfs.ufs.dirhash_mem becomes lower) vfs.ufs.dirhash_maxmem=67108864 # Note from commit http://svn.freebsd.org/base/head@211031 : # For systems with RAID volumes and/or virtualization envirnments, where # read performance is very important, increasing this sysctl tunable to 32 # or even more will demonstratively yield additional performance benefits. vfs.read_max=32 # Explicit Congestion Notification (see http://en.wikipedia.org/wiki/Explicit_Congestion_Notification) net.inet.tcp.ecn.enable=1 # Flowtable - flow caching mechanism # Useful for routers #net.inet.flowtable.enable=1 #net.inet.flowtable.nmbflows=65535 # Extreme polling tuning #kern.polling.burst_max=1000 #kern.polling.each_burst=1000 #kern.polling.reg_frac=100 #kern.polling.user_frac=1 #kern.polling.idle_poll=0 # IPFW dynamic rules and timeouts tuning # Increase dyn_buckets till net.inet.ip.fw.curr_dyn_buckets is lower net.inet.ip.fw.dyn_buckets=65536 net.inet.ip.fw.dyn_max=65536 net.inet.ip.fw.dyn_ack_lifetime=120 net.inet.ip.fw.dyn_syn_lifetime=10 net.inet.ip.fw.dyn_fin_lifetime=2 net.inet.ip.fw.dyn_short_lifetime=10 # Make packets pass firewall only once when using dummynet # i.e. packets going thru pipe are passing out from firewall with accept #net.inet.ip.fw.one_pass=1 # shm_use_phys Wires all shared pages, making them unswappable # Use this to lessen Virtual Memory Manager's work when using Shared Mem. # Useful for databases #kern.ipc.shm_use_phys=1 # ZFS # Enable prefetch. Useful for sequential load type i.e fileserver. # FreeBSD sets vfs.zfs.prefetch_disable to 1 on any i386 systems and # on any amd64 systems with less than 4GB of avaiable memory # For additional info check this nabble thread http://old.nabble.com/Samba-read-speed-performance-tuning-td27964534.html #vfs.zfs.prefetch_disable=0 # On highload servers you may notice following message in dmesg: # "Approaching the limit on PV entries, consider increasing either the # vm.pmap.shpgperproc or the vm.pmap.pv_entry_max tunable" vm.pmap.shpgperproc=2048 loader.conf: # Accept filters for data, http and DNS requests # Useful when your software uses select() instead of kevent/kqueue or when you under DDoS # DNS accf available on 8.0+ accf_data_load="YES" accf_http_load="YES" accf_dns_load="YES" # Async IO system calls aio_load="YES" # Linux specific devices in /dev # As for 8.1 it only /dev/full #lindev_load="YES" # Adds NCQ support in FreeBSD # WARNING! all ad[0-9]+ devices will be renamed to ada[0-9]+ # 8.0+ only #ahci_load="YES" #siis_load="YES" # FreeBSD 8.2+ # New Congestion Control for FreeBSD # http://caia.swin.edu.au/urp/newtcp/tools/cc_chd-readme-0.1.txt # http://www.ietf.org/proceedings/78/slides/iccrg-5.pdf # Initial merge commit message http://www.mail-archive.com/[email protected]/msg31410.html #cc_chd_load="YES" # Increase kernel memory size to 3G. # # Use ONLY if you have KVA_PAGES in kernel configuration, and you have more than 3G RAM # Otherwise panic will happen on next reboot! # # It's required for high buffer sizes: kern.ipc.nmbjumbop, kern.ipc.nmbclusters, etc # Useful on highload stateful firewalls, proxies or ZFS fileservers # (FreeBSD 7.2+ amd64 users: Check that current value is lower!) #vm.kmem_size="3G" # If your server has lots of swap (>4Gb) you should increase following value # according to http://lists.freebsd.org/pipermail/freebsd-hackers/2009-October/029616.html # Otherwise you'll be getting errors # "kernel: swap zone exhausted, increase kern.maxswzone" # kern.maxswzone="256M" # Older versions of FreeBSD can't tune maxfiles on the fly #kern.maxfiles="200000" # Useful for databases # Sets maximum data size to 1G # (FreeBSD 7.2+ amd64 users: Check that current value is lower!) #kern.maxdsiz="1G" # Maximum buffer size(vfs.maxbufspace) # You can check current one via vfs.bufspace # Should be lowered/upped depending on server's load-type # Usually decreased to preserve kmem # (default is 10% of mem) #kern.maxbcache="512M" # Sendfile buffers # For i386 only #kern.ipc.nsfbufs=10240 # FreeBSD 9+ # HPET "legacy route" support. It should allow HPET to work per-CPU # See http://www.mail-archive.com/[email protected]/msg03603.html #hint.atrtc.0.clock=0 #hint.attimer.0.clock=0 #hint.hpet.0.legacy_route=1 # syncache Hash table tuning net.inet.tcp.syncache.hashsize=1024 net.inet.tcp.syncache.bucketlimit=512 net.inet.tcp.syncache.cachelimit=65536 # Increased hostcache # Later host cache can be viewed via net.inet.tcp.hostcache.list hidden sysctl # Very useful for it's RTT RTTVAR # Must be power of two net.inet.tcp.hostcache.hashsize=65536 # hashsize * bucketlimit (which is 30 by default) # It allocates 255Mb (1966080*136) of RAM net.inet.tcp.hostcache.cachelimit=1966080 # TCP control-block Hash table tuning net.inet.tcp.tcbhashsize=4096 # Disable ipfw deny all # Should be uncommented when there is a chance that # kernel and ipfw binary may be out-of sync on next reboot #net.inet.ip.fw.default_to_accept=1 # # SIFTR (Statistical Information For TCP Research) is a kernel module that # logs a range of statistics on active TCP connections to a log file. # See prerelease notes http://groups.google.com/group/mailing.freebsd.current/browse_thread/thread/b4c18be6cdce76e4 # and man 4 sitfr #siftr_load="YES" # Enable superpages, for 7.2+ only # Also read http://lists.freebsd.org/pipermail/freebsd-hackers/2009-November/030094.html vm.pmap.pg_ps_enabled=1 # Usefull if you are using Intel-Gigabit NIC #hw.em.rxd=4096 #hw.em.txd=4096 #hw.em.rx_process_limit="-1" # Also if you have ALOT interrupts on NIC - play with following parameters # NOTE: You should set them for every NIC #dev.em.0.rx_int_delay: 250 #dev.em.0.tx_int_delay: 250 #dev.em.0.rx_abs_int_delay: 250 #dev.em.0.tx_abs_int_delay: 250 # There is also multithreaded version of em/igb drivers can be found here: # http://people.yandex-team.ru/~wawa/ # # for additional em monitoring and statistics use # sysctl dev.em.0.stats=1 ; dmesg # sysctl dev.em.0.debug=1 ; dmesg # Also after r209242 (-CURRENT) there is a separate sysctl for each stat variable; # Same tunings for igb #hw.igb.rxd=4096 #hw.igb.txd=4096 #hw.igb.rx_process_limit=100 # Some useful netisr tunables. See sysctl net.isr #net.isr.maxthreads=4 #net.isr.defaultqlimit=4096 #net.isr.maxqlimit: 10240 # Bind netisr threads to CPUs #net.isr.bindthreads=1 # # FreeBSD 9.x+ # Increase interface send queue length # See commit message http://svn.freebsd.org/viewvc/base?view=revision&revision=207554 #net.link.ifqmaxlen=1024 # Nicer boot logo =) loader_logo="beastie" And finally here is KERNCONF: # Just some of them, see also # cat /sys/{i386,amd64,}/conf/NOTES # This one useful only on i386 #options KVA_PAGES=512 # You can play with HZ in environments with high interrupt rate (default is 1000) # 100 is for my notebook to prolong it's battery life #options HZ=100 # Polling is goot on network loads with high packet rates and low-end NICs # NB! Do not enable it if you want more than one netisr thread #options DEVICE_POLLING # Eliminate datacopy on socket read-write # To take advantage with zero copy sockets you should have an MTU >= 4k # This req. is only for receiving data. # Read more in man zero_copy_sockets # Also this epic thread on kernel trap: # http://kerneltrap.org/node/6506 # Here Linus says that "anybody that does it that way (FreeBSD) is totally incompetent" #options ZERO_COPY_SOCKETS # Support TCP sign. Used for IPSec options TCP_SIGNATURE # There was stackoverflow found in KAME IPSec stack: # See http://secunia.com/advisories/43995/ # For quick workaround you can use `ipfw add deny proto ipcomp` options IPSEC # This ones can be loaded as modules. They described in loader.conf section #options ACCEPT_FILTER_DATA #options ACCEPT_FILTER_HTTP # Adding ipfw, also can be loaded as modules options IPFIREWALL # On 8.1+ you can disable verbose to see blocked packets on ipfw0 interface. # Also there is no point in compiling verbose into the kernel, because # now there is net.inet.ip.fw.verbose tunable. #options IPFIREWALL_VERBOSE #options IPFIREWALL_VERBOSE_LIMIT=10 options IPFIREWALL_FORWARD # Adding kernel NAT options IPFIREWALL_NAT options LIBALIAS # Traffic shaping options DUMMYNET # Divert, i.e. for userspace NAT options IPDIVERT # This is for OpenBSD's pf firewall device pf device pflog # pf's QoS - ALTQ options ALTQ options ALTQ_CBQ # Class Bases Queuing (CBQ) options ALTQ_RED # Random Early Detection (RED) options ALTQ_RIO # RED In/Out options ALTQ_HFSC # Hierarchical Packet Scheduler (HFSC) options ALTQ_PRIQ # Priority Queuing (PRIQ) options ALTQ_NOPCC # Required for SMP build # Pretty console # Manual can be found here http://forums.freebsd.org/showthread.php?t=6134 #options VESA #options SC_PIXEL_MODE # Disable reboot on Ctrl Alt Del #options SC_DISABLE_REBOOT # Change normal|kernel messages color options SC_NORM_ATTR=(FG_GREEN|BG_BLACK) options SC_KERNEL_CONS_ATTR=(FG_YELLOW|BG_BLACK) # More scroll space options SC_HISTORY_SIZE=8192 # Adding hardware crypto device device crypto device cryptodev # Useful network interfaces device vlan device tap #Virtual Ethernet driver device gre #IP over IP tunneling device if_bridge #Bridge interface device pfsync #synchronization interface for PF device carp #Common Address Redundancy Protocol device enc #IPsec interface device lagg #Link aggregation interface device stf #IPv4-IPv6 port # Also for my notebook, but may be used with Opteron device amdtemp # Same for Intel processors device coretemp # man 4 cpuctl device cpuctl # CPU control pseudo-device # Support for ECMP. More than one route for destination # Works even with default route so one can use it as LB for two ISP # For now code is unstable and panics (panic: rtfree 2) on route deletions. #options RADIX_MPATH # Multicast routing #options MROUTING #options PIM # Debug & DTrace options KDB # Kernel debugger related code options KDB_TRACE # Print a stack trace for a panic options KDTRACE_FRAME # amd64-only(?) options KDTRACE_HOOKS # all architectures - enable general DTrace hooks #options DDB #options DDB_CTF # all architectures - kernel ELF linker loads CTF data # Adaptive spining in lockmgr (8.x+) # See http://www.mail-archive.com/[email protected]/msg10782.html options ADAPTIVE_LOCKMGRS # UTF-8 in console (8.x+) #options TEKEN_UTF8 # FreeBSD 8.1+ # Deadlock resolver thread # For additional information see http://www.mail-archive.com/[email protected]/msg18124.html # (FYI: "resolution" is panic so use with caution) #options DEADLKRES # Increase maximum size of Raw I/O and sendfile(2) readahead #options MAXPHYS=(1024*1024) #options MAXBSIZE=(1024*1024) # For scheduler debug enable following option. # Debug will be available via `kern.sched.stats` sysctl # For more information see http://svnweb.freebsd.org/base/head/sys/conf/NOTES?view=markup #options SCHED_STATS If you are tuning network for maximum performance you may wish to play with ifconfig options like: # You can list all capabilities via `ifconfig -m` ifconfig [-]rxcsum [-]txcsum [-]tso [-]lro mtu In case you've enabled DDB in kernel config, you should edit your /etc/ddb.conf and add something like this to enable automatic reboot (and textdump as bonus): script kdb.enter.panic=textdump set; capture on; show pcpu; bt; ps; alltrace; capture off; call doadump; reset script kdb.enter.default=textdump set; capture on; bt; ps; capture off; call doadump; reset And do not forget to add ddb_enable="YES" to /etc/rc.conf Since FreeBSD 9 you can select to enable/disable flowcontrol on your NIC: # See http://en.wikipedia.org/wiki/Ethernet_flow_control and # http://www.mail-archive.com/[email protected]/msg07927.html for additional info ifconfig bge0 media auto mediaopt flowcontrol PS. Also most of FreeBSD's limits can be monitored by # vmstat -z and # limits PPS. variety of network counters can be monitored via # netstat -s In FreeBSD-9 netstat's -Q option appeared, try following command to display netisr stats # netstat -Q PPPS. also see # man 7 tuning PPPPS. I wanted to thank FreeBSD community, especially author of nginx - Igor Sysoev, nginx-ru@ and FreeBSD-performance@ mailing lists for providing useful information about FreeBSD tuning. FreeBSD WIP * Whats cooking for FreeBSD 7? * Whats cooking for FreeBSD 8? * Whats cooking for FreeBSD 9? So here is the question: What tunings are you using on yours FreeBSD servers? You can also post your /etc/sysctl.conf, /boot/loader.conf, kernel options, etc with description of its' meaning (do not copy-paste from sysctl -d). Don't forget to specify server type (web, smb, gateway, etc) Let's share experience!

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• Why do I get Detached Entity exception when upgrading Spring Boot 1.1.4 to 1.1.5

  - by mmeany

  On updating Spring Boot from 1.1.4 to 1.1.5 a simple web application started generating detached entity exceptions. Specifically, a post authentication inteceptor that bumped number of visits was causing the problem. A quick check of loaded dependencies showed that Spring Data has been updated from 1.6.1 to 1.6.2 and a further check of the change log shows a couple of issues relating to optimistic locking, version fields and JPA issues that have been fixed. Well I am using a version field and it starts out as Null following recommendation to not set in the specification. I have produced a very simple test scenario where I get detached entity exceptions if the version field starts as null or zero. If I create an entity with version 1 however then I do not get these exceptions. Is this expected behaviour or is there still something amiss? Below is the test scenario I have for this condition. In the scenario the service layer that has been annotated @Transactional. Each test case makes multiple calls to the service layer - the tests are working with detached entities as this is the scenario I am working with in the full blown application. The test case comprises four tests: Test 1 - versionNullCausesAnExceptionOnUpdate() In this test the version field in the detached object is Null. This is how I would usually create the object prior to passing to the service. This test fails with a Detached Entity exception. I would have expected this test to pass. If there is a flaw in the test then the rest of the scenario is probably moot. Test 2 - versionZeroCausesExceptionOnUpdate() In this test I have set the version to value Long(0L). This is an edge case test and included because I found reference to Zero values being used for version field in the Spring Data change log. This test fails with a Detached Entity exception. Of interest simply because the following two tests pass leaving this as an anomaly. Test 3 - versionOneDoesNotCausesExceptionOnUpdate() In this test the version field is set to value Long(1L). Not something I would usually do, but considering the notes in the Spring Data change log I decided to give it a go. This test passes. Would not usually set the version field, but this looks like a work-around until I figure out why the first test is failing. Test 4 - versionOneDoesNotCausesExceptionWithMultipleUpdates() Encouraged by the result of test 3 I pushed the scenario a step further and perform multiple updates on the entity that started life with a version of Long(1L). This test passes. Reinforcement that this may be a useable work-around. The entity: package com.mvmlabs.domain; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.Table; import javax.persistence.Version; @Entity @Table(name="user_details") public class User { @Id @GeneratedValue(strategy=GenerationType.AUTO) private Long id; @Version private Long version; @Column(nullable = false, unique = true) private String username; @Column(nullable = false) private Integer numberOfVisits; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public Long getVersion() { return version; } public void setVersion(Long version) { this.version = version; } public Integer getNumberOfVisits() { return numberOfVisits == null ? 0 : numberOfVisits; } public void setNumberOfVisits(Integer numberOfVisits) { this.numberOfVisits = numberOfVisits; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } } The repository: package com.mvmlabs.dao; import org.springframework.data.repository.CrudRepository; import com.mvmlabs.domain.User; public interface UserDao extends CrudRepository<User, Long>{ } The service interface: package com.mvmlabs.service; import com.mvmlabs.domain.User; public interface UserService { User save(User user); User loadUser(Long id); User registerVisit(User user); } The service implementation: package com.mvmlabs.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Propagation; import org.springframework.transaction.annotation.Transactional; import org.springframework.transaction.support.TransactionSynchronizationManager; import com.mvmlabs.dao.UserDao; import com.mvmlabs.domain.User; @Service @Transactional(propagation=Propagation.REQUIRED, readOnly=false) public class UserServiceJpaImpl implements UserService { @Autowired private UserDao userDao; @Transactional(readOnly=true) @Override public User loadUser(Long id) { return userDao.findOne(id); } @Override public User registerVisit(User user) { user.setNumberOfVisits(user.getNumberOfVisits() + 1); return userDao.save(user); } @Override public User save(User user) { return userDao.save(user); } } The application class: package com.mvmlabs; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; @Configuration @ComponentScan @EnableAutoConfiguration public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } } The POM: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.mvmlabs</groupId> <artifactId>jpa-issue</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>spring-boot-jpa-issue</name> <description>JPA Issue between spring boot 1.1.4 and 1.1.5</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.1.5.RELEASE</version> <relativePath /> <!-- lookup parent from repository --> </parent> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.hsqldb</groupId> <artifactId>hsqldb</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <start-class>com.mvmlabs.Application</start-class> <java.version>1.7</java.version> </properties> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> The application properties: spring.jpa.hibernate.ddl-auto: create spring.jpa.hibernate.naming_strategy: org.hibernate.cfg.ImprovedNamingStrategy spring.jpa.database: HSQL spring.jpa.show-sql: true spring.datasource.url=jdbc:hsqldb:file:./target/testdb spring.datasource.username=sa spring.datasource.password= spring.datasource.driverClassName=org.hsqldb.jdbcDriver The test case: package com.mvmlabs; import org.junit.Assert; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.SpringApplicationConfiguration; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import com.mvmlabs.domain.User; import com.mvmlabs.service.UserService; @RunWith(SpringJUnit4ClassRunner.class) @SpringApplicationConfiguration(classes = Application.class) public class ApplicationTests { @Autowired UserService userService; @Test public void versionNullCausesAnExceptionOnUpdate() throws Exception { User user = new User(); user.setUsername("Version Null"); user.setNumberOfVisits(0); user.setVersion(null); user = userService.save(user); user = userService.registerVisit(user); Assert.assertEquals(new Integer(1), user.getNumberOfVisits()); Assert.assertEquals(new Long(1L), user.getVersion()); } @Test public void versionZeroCausesExceptionOnUpdate() throws Exception { User user = new User(); user.setUsername("Version Zero"); user.setNumberOfVisits(0); user.setVersion(0L); user = userService.save(user); user = userService.registerVisit(user); Assert.assertEquals(new Integer(1), user.getNumberOfVisits()); Assert.assertEquals(new Long(1L), user.getVersion()); } @Test public void versionOneDoesNotCausesExceptionOnUpdate() throws Exception { User user = new User(); user.setUsername("Version One"); user.setNumberOfVisits(0); user.setVersion(1L); user = userService.save(user); user = userService.registerVisit(user); Assert.assertEquals(new Integer(1), user.getNumberOfVisits()); Assert.assertEquals(new Long(2L), user.getVersion()); } @Test public void versionOneDoesNotCausesExceptionWithMultipleUpdates() throws Exception { User user = new User(); user.setUsername("Version One Multiple"); user.setNumberOfVisits(0); user.setVersion(1L); user = userService.save(user); user = userService.registerVisit(user); user = userService.registerVisit(user); user = userService.registerVisit(user); Assert.assertEquals(new Integer(3), user.getNumberOfVisits()); Assert.assertEquals(new Long(4L), user.getVersion()); } } The first two tests fail with detached entity exception. The last two tests pass as expected. Now change Spring Boot version to 1.1.4 and rerun, all tests pass. Are my expectations wrong? Edit: This code saved to GitHub at https://github.com/mmeany/spring-boot-detached-entity-issue

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