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  • Create folder for todays date

    - by Ram
    Hi, I have a folder named as 2010. In this I want a folder for each month like "Jan10", "Feb10"....."Dec10" In each month folder I want to create folder for "Todays date" I have create a shortcut for that 2010 folder with Target as C:\WINDOWS\explorer.exe /n, /e, /select, F:\2010 I want a functionality that will execute when I click the shortcut for f:\2010 icon. Any pointer would be great help.

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  • phonegap crash on "resume"

    - by fancy
    My phonegap application works great but there is a glitch when it is sent to the background or "paused". When focused is returned to the app a high percentage of the time the interface is frozen and then the application crashes a few seconds later. When relaunched it is working fine again. Could anyone provide some information as to what could be causing this and where I should start trying to debug it? Thanks very much.

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  • Can emacs generate a table of comments and number sections of a document?

    - by mp3foley
    I'm writing a plain text document with numbered sections or chapters and am wondering if emacs can help with numbering and re-numbering sections. And of course would be great if it could then generate a table of contents as well. I have had a search on google and looked through the emacs wiki but did not come up with anything other than for latex stuff and possibly muse mode, but I would like to keep this as a plain text README style document. Thanks for any help or suggestions.

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  • Dependency Properties

    - by developer
    Hi All, Can anybody explain me what a dependency property is in WPF and what is its use. I know there are a lot of tutorials on google for it, but they teach how to create a dependency property. I am confused as to where I would use it. I mean will I use it in XAML? If anybody could explain me in simple terms, that would be great.

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  • when was RAII added to C++

    - by Magnus
    I recently learned about the wonderful memory management technique of RAII, which seems so much cleaner than the new/delete headache I learned in school years ago (I haven't looked at much C++ during the intervening years). I'm trying to track down when this great technique was added to C++. Was it always there and I just missed the memo? What's the oldest version of the C++ standard which supports RAII?

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  • Bullet physics debug drawing not working

    - by Krishnabhadra
    Background I am following on from this question, which isn't answered yet. Basically I have a cube and a UVSphere in my scene, with UVSphere on the top of the cube without touching the cube. Both exported from blender. When I run the app The UVSphere does circle around the cube for 3 or 4 times and jump out of the scene. What I actually expect was the sphere to fall on top of the cube. What this question about From the comment to the linked question, I got to know about bullet debug drawing, which helps in debugging by drawing outline of physics bodies which are normally invisible. I did some research on that and came up with the code given below. From whatever I have read, below code should work, but it doesn't. My Code My bullet initialization code. -(void) initializeScene { /*Setup physics world*/ _physicsWorld = [[CC3PhysicsWorld alloc] init]; [_physicsWorld setGravity:0 y:-9.8 z:0]; /*Setting up debug draw*/ MyDebugDraw *draw = new MyDebugDraw; draw->setDebugMode(draw->getDebugMode() | btIDebugDraw::DBG_DrawWireframe ); _physicsWorld._discreteDynamicsWorld->setDebugDrawer(draw); /*Setup camera and lamb*/ ………….. //This simpleCube.pod contains the cube [self addContentFromPODFile: @"simpleCube.pod"]; //This file contains sphere [self addContentFromPODFile: @"SimpleSphere.pod"]; [self createGLBuffers]; CC3MeshNode* cubeNode = (CC3MeshNode*)[self getNodeNamed:@"Cube"]; CC3MeshNode* sphereNode = (CC3MeshNode*)[self getNodeNamed:@"Sphere"]; // both cubeNode and sphereNode are not nil from this point float *cVertexData = (float*)((CC3VertexArrayMesh*)cubeNode.mesh) .vertexLocations.vertices; int cVertexCount = ((CC3VertexArrayMesh*)cubeNode.mesh) .vertexLocations.vertexCount; btTriangleMesh* cTriangleMesh = new btTriangleMesh(); int offset = 0; for (int i = 0; i < (cVertexCount / 3); i++) { unsigned int index1 = offset; unsigned int index2 = offset+6; unsigned int index3 = offset+12; cTriangleMesh->addTriangle( btVector3(cVertexData[index1], cVertexData[index1+1], cVertexData[index1+2]), btVector3(cVertexData[index2], cVertexData[index2+1], cVertexData[index2+2]), btVector3(cVertexData[index3], cVertexData[index3+1], cVertexData[index3+2])); offset += 18; } [self releaseRedundantData]; /*Create a triangle mesh from the vertices*/ btBvhTriangleMeshShape* cTriMeshShape = new btBvhTriangleMeshShape(cTriangleMesh,true); btCollisionShape *sphereShape = new btSphereShape(1); gTriMeshObject = [_physicsWorld createPhysicsObjectTrimesh:cubeNode shape:cTriMeshShape mass:0 restitution:1.0 position:cubeNode.location]; sphereObject = [_physicsWorld createPhysicsObject:sphereNode shape:sphereShape mass:1 restitution:0.1 position:sphereNode.location]; sphereObject.rigidBody->setDamping(0.1,0.8); /*Enable debug drawing*/ _physicsWorld._discreteDynamicsWorld->debugDrawWorld(); } And My btIDebugDraw implementation (MyDebugDraw.h) //MyDebugDraw.h class MyDebugDraw: public btIDebugDraw{ int m_debugMode; public: virtual void drawLine(const btVector3& from,const btVector3& to ,const btVector3& color); virtual void drawContactPoint(const btVector3& PointOnB ,const btVector3& normalOnB,btScalar distance ,int lifeTime,const btVector3& color); virtual void reportErrorWarning(const char* warningString); virtual void draw3dText(const btVector3& location ,const char* textString); virtual void setDebugMode(int debugMode); virtual int getDebugMode() const; }; void MyDebugDraw::drawLine(const btVector3& from,const btVector3& to ,const btVector3& color){ LogInfo(@"Works!!"); glPushMatrix(); glColor4f(color.getX(), color.getY(), color.getZ(), 1.0); const GLfloat line[] = { from.getX()*1, from.getY()*1, from.getZ()*1, //point A to.getX()*1, to.getY()*1,to.getZ()*1 //point B }; glVertexPointer( 3, GL_FLOAT, 0, &line ); glPointSize( 5.0f ); glDrawArrays( GL_POINTS, 0, 2 ); glDrawArrays( GL_LINES, 0, 2 ); glPopMatrix(); } void MyDebugDraw::drawContactPoint(const btVector3 &PointOnB ,const btVector3 &normalOnB, btScalar distance ,int lifeTime, const btVector3 &color){ } void MyDebugDraw::reportErrorWarning(const char *warningString){ } void MyDebugDraw::draw3dText(const btVector3 &location , const char *textString){ } void MyDebugDraw::setDebugMode(int debugMode){ } int MyDebugDraw::getDebugMode() const{ return DBG_DrawWireframe; } My Problem The drawLine method is getting called. I can see the cube and sphere in place. Sphere again does some circling around the cube before jumping off. No debug lines are getting drawn.

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  • Flood fill algorithm for Game of Go

    - by Jackson Borghi
    I'm having a hell of a time trying to figure out how to make captured stones disappear. I've read everywhere that I should use the flood fill algorithm, but I haven't had any luck with that so far. Any help would be amazing! Here is my code: package Go; import static java.lang.Math.*; import static stdlib.StdDraw.*; import java.awt.Color; public class Go2 { public static Color opposite(Color player) { if (player == WHITE) { return BLACK; } return WHITE; } public static void drawGame(Color[][] board) { Color[][][] unit = new Color[400][19][19]; for (int h = 0; h < 400; h++) { for (int x = 0; x < 19; x++) { for (int y = 0; y < 19; y++) { unit[h][x][y] = YELLOW; } } } setXscale(0, 19); setYscale(0, 19); clear(YELLOW); setPenColor(BLACK); line(0, 0, 0, 19); line(19, 19, 19, 0); line(0, 19, 19, 19); line(0, 0, 19, 0); for (double i = 0; i < 19; i++) { line(0.0, i, 19, i); line(i, 0.0, i, 19); } for (int x = 0; x < 19; x++) { for (int y = 0; y < 19; y++) { if (board[x][y] != YELLOW) { setPenColor(board[x][y]); filledCircle(x, y, 0.47); setPenColor(GRAY); circle(x, y, 0.47); } } } int h = 0; } public static void main(String[] args) { int px; int py; Color[][] temp = new Color[19][19]; Color[][] board = new Color[19][19]; Color player = WHITE; for (int i = 0; i < 19; i++) { for (int h = 0; h < 19; h++) { board[i][h] = YELLOW; temp[i][h] = YELLOW; } } while (true) { drawGame(board); while (!mousePressed()) { } px = (int) round(mouseX()); py = (int) round(mouseY()); board[px][py] = player; while (mousePressed()) { } floodFill(px, py, player, board, temp); System.out.print("XXXXX = "+ temp[px][py]); if (checkTemp(temp, board, px, py)) { for (int x = 0; x < 19; x++) { for (int y = 0; y < 19; y++) { if (temp[x][y] == GRAY) { board[x][y] = YELLOW; } } } } player = opposite(player); } } private static boolean checkTemp(Color[][] temp, Color[][] board, int x, int y) { if (x < 19 && x > -1 && y < 19 && y > -1) { if (temp[x + 1][y] == YELLOW || temp[x - 1][y] == YELLOW || temp[x][y - 1] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } if (x == 18) { if (temp[x - 1][y] == YELLOW || temp[x][y - 1] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } if (y == 18) { if (temp[x + 1][y] == YELLOW || temp[x - 1][y] == YELLOW || temp[x][y - 1] == YELLOW) { return false; } } if (y == 0) { if (temp[x + 1][y] == YELLOW || temp[x - 1][y] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } if (x == 0) { if (temp[x + 1][y] == YELLOW || temp[x][y - 1] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } else { if (x < 19) { if (temp[x + 1][y] == GRAY) { checkTemp(temp, board, x + 1, y); } } if (x >= 0) { if (temp[x - 1][y] == GRAY) { checkTemp(temp, board, x - 1, y); } } if (y < 19) { if (temp[x][y + 1] == GRAY) { checkTemp(temp, board, x, y + 1); } } if (y >= 0) { if (temp[x][y - 1] == GRAY) { checkTemp(temp, board, x, y - 1); } } } return true; } private static void floodFill(int x, int y, Color player, Color[][] board, Color[][] temp) { if (board[x][y] != player) { return; } else { temp[x][y] = GRAY; System.out.println("x = " + x + " y = " + y); if (x < 19) { floodFill(x + 1, y, player, board, temp); } if (x >= 0) { floodFill(x - 1, y, player, board, temp); } if (y < 19) { floodFill(x, y + 1, player, board, temp); } if (y >= 0) { floodFill(x, y - 1, player, board, temp); } } } }

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  • FloodFill Algorithm for Game of Go

    - by Jackson Borghi
    I'm having a hell of a time trying to figure out how to make captured stones disappear. I've read everywhere that I should use the FloodFill algorithm, but I havent had any luck with that so far. Any help would be amazing! Here is my code: package Go; import static java.lang.Math.; import static stdlib.StdDraw.; import java.awt.Color; public class Go2 { public static Color opposite(Color player) { if (player == WHITE) { return BLACK; } return WHITE; } public static void drawGame(Color[][] board) { Color[][][] unit = new Color[400][19][19]; for (int h = 0; h < 400; h++) { for (int x = 0; x < 19; x++) { for (int y = 0; y < 19; y++) { unit[h][x][y] = YELLOW; } } } setXscale(0, 19); setYscale(0, 19); clear(YELLOW); setPenColor(BLACK); line(0, 0, 0, 19); line(19, 19, 19, 0); line(0, 19, 19, 19); line(0, 0, 19, 0); for (double i = 0; i < 19; i++) { line(0.0, i, 19, i); line(i, 0.0, i, 19); } for (int x = 0; x < 19; x++) { for (int y = 0; y < 19; y++) { if (board[x][y] != YELLOW) { setPenColor(board[x][y]); filledCircle(x, y, 0.47); setPenColor(GRAY); circle(x, y, 0.47); } } } int h = 0; } public static void main(String[] args) { int px; int py; Color[][] temp = new Color[19][19]; Color[][] board = new Color[19][19]; Color player = WHITE; for (int i = 0; i < 19; i++) { for (int h = 0; h < 19; h++) { board[i][h] = YELLOW; temp[i][h] = YELLOW; } } while (true) { drawGame(board); while (!mousePressed()) { } px = (int) round(mouseX()); py = (int) round(mouseY()); board[px][py] = player; while (mousePressed()) { } floodFill(px, py, player, board, temp); System.out.print("XXXXX = "+ temp[px][py]); if (checkTemp(temp, board, px, py)) { for (int x = 0; x < 19; x++) { for (int y = 0; y < 19; y++) { if (temp[x][y] == GRAY) { board[x][y] = YELLOW; } } } } player = opposite(player); } } private static boolean checkTemp(Color[][] temp, Color[][] board, int x, int y) { if (x < 19 && x > -1 && y < 19 && y > -1) { if (temp[x + 1][y] == YELLOW || temp[x - 1][y] == YELLOW || temp[x][y - 1] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } if (x == 18) { if (temp[x - 1][y] == YELLOW || temp[x][y - 1] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } if (y == 18) { if (temp[x + 1][y] == YELLOW || temp[x - 1][y] == YELLOW || temp[x][y - 1] == YELLOW) { return false; } } if (y == 0) { if (temp[x + 1][y] == YELLOW || temp[x - 1][y] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } if (x == 0) { if (temp[x + 1][y] == YELLOW || temp[x][y - 1] == YELLOW || temp[x][y + 1] == YELLOW) { return false; } } else { if (x < 19) { if (temp[x + 1][y] == GRAY) { checkTemp(temp, board, x + 1, y); } } if (x >= 0) { if (temp[x - 1][y] == GRAY) { checkTemp(temp, board, x - 1, y); } } if (y < 19) { if (temp[x][y + 1] == GRAY) { checkTemp(temp, board, x, y + 1); } } if (y >= 0) { if (temp[x][y - 1] == GRAY) { checkTemp(temp, board, x, y - 1); } } } return true; } private static void floodFill(int x, int y, Color player, Color[][] board, Color[][] temp) { if (board[x][y] != player) { return; } else { temp[x][y] = GRAY; System.out.println("x = " + x + " y = " + y); if (x < 19) { floodFill(x + 1, y, player, board, temp); } if (x >= 0) { floodFill(x - 1, y, player, board, temp); } if (y < 19) { floodFill(x, y + 1, player, board, temp); } if (y >= 0) { floodFill(x, y - 1, player, board, temp); } } } }

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  • Global Perspective: Oracle AppAdvantage Does its Stage Debut in the UK

    - by Tanu Sood
    Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Global Perspective is a monthly series that brings experiences, business needs and real-world use cases from regions across the globe. This month’s feature is a follow-up from last month’s Global Perspective note from a well known ACE Director based in EMEA. My first contribution to this blog was before Oracle Open World and I was quite excited about where this initiative would take me in my understanding of the value of Oracle Fusion Middleware. Rimi Bewtra from the Oracle AppAdvantage team came as promised to the Oracle ACE Director briefings and explained what this initiative was all about and I then asked the directors to take part in the new survey. The story was really well received and then at the SOA advisory board that many of these ACE Directors already take part in there was a further discussion on how this initiative will help customers understand the benefits of adoption. A few days later Rick Beers launched the program at a lunch of invited customer executives which included one from Pella who talked about their projects (a quick recap on that here). I wasn’t able to stay for the whole event but what really interested me was that these executives who understood the technology but where looking for how they could use them to drive their businesses. Lots of ideas were bubbling up in my head about how we can use this in user groups to help our members, and the timing was fantastic as just three weeks later we had UKOUG_Apps13, our flagship Applications conference in the UK. We had independently working with Oracle marketing in the UK on an initiative called Apps Transformation to help our members look beyond just the application they use today. We have had a Fusion community page but felt the options open are now much wider than Fusion Applications, there are acquired applications, social, mobility and of course the underlying technology, Oracle Fusion Middleware. I was really pleased to be allowed to give the Oracle AppAdvantage story as a session in our conference and we are planning a special Apps Transformation event in March where I hope the Oracle AppAdvantage team will take part and we will have the results of the survey to discuss. But, life also came full circle for me. In my first post, I talked about Andrew Sutherland and his original theory that Oracle Fusion Middleware adoption had technical drivers. Well, Andrew was a speaker at our event and he gave a potted, tech-talk free update on Oracle Open World. Andrew talked about the Prevailing Technology Winds, and what is driving this today and he talked about that in the past it was the move from simply automating processes (ERP etc), through the altering of those processes (SOA) and onto consolidation. The next drivers are around the need to predict, both faster and more accurately; how to better exploit the information that we have available. He went on to talk about The Nexus of Forces: Social, Mobile, Cloud and Information – harnessing these forces of change with Oracle technology. Gartner really likes this concept and if you want to know more you can get their paper here. All this has made me think, and I hope it will make you too. Technology can help us drive our businesses better and understanding your needs can be the first step on your journey, which was the theme of our event in the UK. I spoke to a number of the delegates and I hope to share some of their stories in later posts. If you have a story to share, the survey is at: https://www.surveymonkey.com/s/P335DD3 About the Author: Debra Lilley, Fujitsu Fusion Champion, UKOUG Board Member, Fusion User Experience Advocate and ACE Director. Debra has 18 years experience with Oracle Applications, with E Business Suite since 9.4.1, moving to Business Intelligence Team Leader and then Oracle Alliance Director. She has spoken at over 100 conferences worldwide and posts at debrasoraclethoughts Editor’s Note: Debra has kindly agreed to share her musings and experience in a monthly column on the Fusion Middleware blog so do stay tuned…

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  • C#/.NET Little Wonders: Static Char Methods

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Often times in our code we deal with the bigger classes and types in the BCL, and occasionally forgot that there are some nice methods on the primitive types as well.  Today we will discuss some of the handy static methods that exist on the char (the C# alias of System.Char) type. The Background I was examining a piece of code this week where I saw the following: 1: // need to get the 5th (offset 4) character in upper case 2: var type = symbol.Substring(4, 1).ToUpper(); 3:  4: // test to see if the type is P 5: if (type == "P") 6: { 7: // ... do something with P type... 8: } Is there really any error in this code?  No, but it still struck me wrong because it is allocating two very short-lived throw-away strings, just to store and manipulate a single char: The call to Substring() generates a new string of length 1 The call to ToUpper() generates a new upper-case version of the string from Step 1. In my mind this is similar to using ToUpper() to do a case-insensitive compare: it isn’t wrong, it’s just much heavier than it needs to be (for more info on case-insensitive compares, see #2 in 5 More Little Wonders). One of my favorite books is the C++ Coding Standards: 101 Rules, Guidelines, and Best Practices by Sutter and Alexandrescu.  True, it’s about C++ standards, but there’s also some great general programming advice in there, including two rules I love:         8. Don’t Optimize Prematurely         9. Don’t Pessimize Prematurely We all know what #8 means: don’t optimize when there is no immediate need, especially at the expense of readability and maintainability.  I firmly believe this and in the axiom: it’s easier to make correct code fast than to make fast code correct.  Optimizing code to the point that it becomes difficult to maintain often gains little and often gives you little bang for the buck. But what about #9?  Well, for that they state: “All other things being equal, notably code complexity and readability, certain efficient design patterns and coding idioms should just flow naturally from your fingertips and are no harder to write then the pessimized alternatives. This is not premature optimization; it is avoiding gratuitous pessimization.” Or, if I may paraphrase: “where it doesn’t increase the code complexity and readability, prefer the more efficient option”. The example code above was one of those times I feel where we are violating a tacit C# coding idiom: avoid creating unnecessary temporary strings.  The code creates temporary strings to hold one char, which is just unnecessary.  I think the original coder thought he had to do this because ToUpper() is an instance method on string but not on char.  What he didn’t know, however, is that ToUpper() does exist on char, it’s just a static method instead (though you could write an extension method to make it look instance-ish). This leads me (in a long-winded way) to my Little Wonders for the day… Static Methods of System.Char So let’s look at some of these handy, and often overlooked, static methods on the char type: IsDigit(), IsLetter(), IsLetterOrDigit(), IsPunctuation(), IsWhiteSpace() Methods to tell you whether a char (or position in a string) belongs to a category of characters. IsLower(), IsUpper() Methods that check if a char (or position in a string) is lower or upper case ToLower(), ToUpper() Methods that convert a single char to the lower or upper equivalent. For example, if you wanted to see if a string contained any lower case characters, you could do the following: 1: if (symbol.Any(c => char.IsLower(c))) 2: { 3: // ... 4: } Which, incidentally, we could use a method group to shorten the expression to: 1: if (symbol.Any(char.IsLower)) 2: { 3: // ... 4: } Or, if you wanted to verify that all of the characters in a string are digits: 1: if (symbol.All(char.IsDigit)) 2: { 3: // ... 4: } Also, for the IsXxx() methods, there are overloads that take either a char, or a string and an index, this means that these two calls are logically identical: 1: // check given a character 2: if (char.IsUpper(symbol[0])) { ... } 3:  4: // check given a string and index 5: if (char.IsUpper(symbol, 0)) { ... } Obviously, if you just have a char, then you’d just use the first form.  But if you have a string you can use either form equally well. As a side note, care should be taken when examining all the available static methods on the System.Char type, as some seem to be redundant but actually have very different purposes.  For example, there are IsDigit() and IsNumeric() methods, which sound the same on the surface, but give you different results. IsDigit() returns true if it is a base-10 digit character (‘0’, ‘1’, … ‘9’) where IsNumeric() returns true if it’s any numeric character including the characters for ½, ¼, etc. Summary To come full circle back to our opening example, I would have preferred the code be written like this: 1: // grab 5th char and take upper case version of it 2: var type = char.ToUpper(symbol[4]); 3:  4: if (type == 'P') 5: { 6: // ... do something with P type... 7: } Not only is it just as readable (if not more so), but it performs over 3x faster on my machine:    1,000,000 iterations of char method took: 30 ms, 0.000050 ms/item.    1,000,000 iterations of string method took: 101 ms, 0.000101 ms/item. It’s not only immediately faster because we don’t allocate temporary strings, but as an added bonus there less garbage to collect later as well.  To me this qualifies as a case where we are using a common C# performance idiom (don’t create unnecessary temporary strings) to make our code better. Technorati Tags: C#,CSharp,.NET,Little Wonders,char,string

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  • To Bit or Not To Bit

    - by Johnm
    'Twas a long day of troubleshooting and firefighting and now, with most of the office vacant, you face a blank scripting window to create a new table in his database. Many questions circle your mind like dirty water gurgling down the bathtub drain: "How normalized should this table be?", "Should I use an identity column?", "NVarchar or Varchar?", "Should this column be NULLABLE?", "I wonder what apple blue cheese bacon cheesecake tastes like?" Well, there are times when the mind goes it's own direction. A Bit About Bit At some point during your table creation efforts you will encounter the decision of whether to use the bit data type for a column. The bit data type is an integer data type that recognizes only the values of 1, 0 and NULL as valid. This data type is often utilized to store yes/no or true/false values. An example of its use would be a column called [IsGasoline] which would be intended to contain the value of 1 if the row's subject (a car) had a gasoline engine and a 0 if the subject did not have a gasoline engine. The bit data type can even be found in some of the system tables of SQL Server. For example, the sysssispackages table in the msdb database which contains SQL Server Integration Services Package information for the packages stored in SQL Server. This table contains a column called [IsEncrypted]. A value of 1 indicates that the package has been encrypted while the value of 0 indicates that it is not. I have learned that the most effective way to disperse the crowd that surrounds the office coffee machine is to engage into SQL Server debates. The bit data type has been one of the most reoccurring, as well as the most enjoyable, of these topics. It contains a practical side and a philosophical side. Practical Consideration This data type certainly has its place and is a valuable option for database design; but it is often used in situations where the answer is really not a pure true/false response. In addition, true/false values are not very informative or scalable. Let's use the previously noted [IsGasoline] column for illustration. While on the surface it appears to be a rather simple question when evaluating a car: "Does the car have a gasoline engine?" If the person entering data is entering a row for a Jeep Liberty, the response would be a 1 since it has a gasoline engine. If the person is entering data is entering a row for a Chevrolet Volt, the response would be a 0 since it is an electric engine. What happens when a person is entering a row for the gasoline/electric hybrid Toyota Prius? Would one person's conclusion be consistent with another person's conclusion? The argument could be made that the current intent for the database is to be used only for pure gasoline and pure electric engines; but this is where the scalability issue comes into play. With the use of a bit data type a database modification and data conversion would be required if the business decided to take on hybrid engines. Whereas, alternatively, if the int data type were used as a foreign key to a reference table containing the engine type options, the change to include the hybrid option would only require an entry into the reference table. Philosophical Consideration Since the bit data type is often used for true/false or yes/no data (also called Boolean) it presents a philosophical conundrum of what to do about the allowance of the NULL value. The inclusion of NULL in a true/false or yes/no response simply violates the logical principle of bivalence which states that "every proposition is either true or false". If NULL is not true, then it must be false. The mathematical laws of Boolean logic support this concept by stating that the only valid values of this scenario are 1 and 0. There is another way to look at this conundrum: NULL is also considered to be the absence of a response. In other words, it is the equivalent to "undecided". Anyone who watches the news can tell you that polls always include an "undecided" option. This could be considered a valid option in the world of yes/no/dunno. Through out all of these considerations I have discovered one absolute certainty: When you have found a person, or group of persons, who are willing to entertain a philosophical debate of the bit data type, you have found some true friends.

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  • Which of these algorithms is best for my goal?

    - by JonathonG
    I have created a program that restricts the mouse to a certain region based on a black/white bitmap. The program is 100% functional as-is, but uses an inaccurate, albeit fast, algorithm for repositioning the mouse when it strays outside the area. Currently, when the mouse moves outside the area, basically what happens is this: A line is drawn between a pre-defined static point inside the region and the mouse's new position. The point where that line intersects the edge of the allowed area is found. The mouse is moved to that point. This works, but only works perfectly for a perfect circle with the pre-defined point set in the exact center. Unfortunately, this will never be the case. The application will be used with a variety of rectangles and irregular, amorphous shapes. On such shapes, the point where the line drawn intersects the edge will usually not be the closest point on the shape to the mouse. I need to create a new algorithm that finds the closest point to the mouse's new position on the edge of the allowed area. I have several ideas about this, but I am not sure of their validity, in that they may have far too much overhead. While I am not asking for code, it might help to know that I am using Objective C / Cocoa, developing for OS X, as I feel the language being used might affect the efficiency of potential methods. My ideas are: Using a bit of trigonometry to project lines would work, but that would require some kind of intense algorithm to test every point on every line until it found the edge of the region... That seems too resource intensive since there could be something like 200 lines that would have each have to have as many as 200 pixels checked for black/white.... Using something like an A* pathing algorithm to find the shortest path to a black pixel; however, A* seems resource intensive, even though I could probably restrict it to only checking roughly in one direction. It also seems like it will take more time and effort than I have available to spend on this small portion of the much larger project I am working on, correct me if I am wrong and it would not be a significant amount of code (100 lines or around there). Mapping the border of the region before the application begins running the event tap loop. I think I could accomplish this by using my current line-based algorithm to find an edge point and then initiating an algorithm that checks all 8 pixels around that pixel, finds the next border pixel in one direction, and continues to do this until it comes back to the starting pixel. I could then store that data in an array to be used for the entire duration of the program, and have the mouse re-positioning method check the array for the closest pixel on the border to the mouse target position. That last method would presumably execute it's initial border mapping fairly quickly. (It would only have to map between 2,000 and 8,000 pixels, which means 8,000 to 64,000 checked, and I could even permanently store the data to make launching faster.) However, I am uncertain as to how much overhead it would take to scan through that array for the shortest distance for every single mouse move event... I suppose there could be a shortcut to restrict the number of elements in the array that will be checked to a variable number starting with the intersecting point on the line (from my original algorithm), and raise/lower that number to experiment with the overhead/accuracy tradeoff. Please let me know if I am over thinking this and there is an easier way that will work just fine, or which of these methods would be able to execute something like 30 times per second to keep mouse movement smooth, or if you have a better/faster method. I've posted relevant parts of my code below for reference, and included an example of what the area might look like. (I check for color value against a loaded bitmap that is black/white.) // // This part of my code runs every single time the mouse moves. // CGPoint point = CGEventGetLocation(event); float tX = point.x; float tY = point.y; if( is_in_area(tX,tY, mouse_mask)){ // target is inside O.K. area, do nothing }else{ CGPoint target; //point inside restricted region: float iX = 600; // inside x float iY = 500; // inside y // delta to midpoint between iX,iY and tX,tY float dX; float dY; float accuracy = .5; //accuracy to loop until reached do { dX = (tX-iX)/2; dY = (tY-iY)/2; if(is_in_area((tX-dX),(tY-dY),mouse_mask)){ iX += dX; iY += dY; } else { tX -= dX; tY -= dY; } } while (abs(dX)>accuracy || abs(dY)>accuracy); target = CGPointMake(roundf(tX), roundf(tY)); CGDisplayMoveCursorToPoint(CGMainDisplayID(),target); } Here is "is_in_area(int x, int y)" : bool is_in_area(NSInteger x, NSInteger y, NSBitmapImageRep *mouse_mask){ NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; NSUInteger pixel[4]; [mouse_mask getPixel:pixel atX:x y:y]; if(pixel[0]!= 0){ [pool release]; return false; } [pool release]; return true; }

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  • Using Resources the Right Way

    - by BuckWoody
    It’s an interesting time in computing technology. At one point there was a dearth of information available for solving a given problem, or educating ourselves on broader topics so that we can solve problems in the future. With dozens, perhaps hundreds or thousands of web sites and content available (for free, in many cases) from vendors, peers, even colleges and universities, it seems like there is actually too much information. Who has the time to absorb all this information and training? Even if you had the inclination, where to start? In fact, it seems so overwhelming that I often hear people saying that they can’t find the training they need, or that vendor X or Y “doesn’t help their users”. On questioning these folks, however, I often find that they – and sometimes I - haven’t put in the effort to learn what resources we have. That’s where blogs, like this one, can help. If you follow a blog, either by checking it often or perhaps subscribing to the Really Simple Syndication (RSS) feed, you’ll be able to spread out the search or create a mental filter for the information you need. But it’s not enough just read a blog or a web page. The creators need real feedback – what doesn’t work, and what does. Yes, you’re allowed to tell a vendor or writer “This helped me because…” so that you reinforce the positives. To be sure, bring up what doesn’t work as well –  that’s fine. But be specific, and be constructive. You’d be surprised at how much it matters. I know for a fact at Microsoft we listen – there is a real live person that reads your comments. I’m sure this is true of other vendors, and I also know that most blog authors – yours truly most especially – wants to know what you think.   In this blog entry I’d to call your attention to three resources you have at your disposal, and how you can use them to help. I’ll try to bring up things like this from time to time that I find useful, and cover in them in more depth like this. Think of this as a synopsis of a longer set of resources that you can use to filter whether you want to research further, bookmark, or forward on to a circle of friends where you think it might help them.   Data Driven Design Concepts http://msdn.microsoft.com/en-us/library/windowsazure/jj156154 I’ll start with a great site that walks you through the process of designing a solution from a data-first perspective. As you know, I believe all computing is merely re-arranging data. If you follow that logic as well, you’ll realize that whenever you create a solution, you should start at the data-end of the application. This resource helps you do that. Even if you don’t use the specific technologies the instructions use, the concepts hold for almost any other technology that deals with data. This should be a definite bookmark for a developer, DBA, or Data Architect. When I mentioned my admiration for this resource here at Microsoft, the team that created it contacted me and asked if I’d share an e-mail address to my readers so that you can comment on it. You’re guaranteed to be heard – you can suggest changes, talk about how useful – or not – it is, and so on. Here’s that address:  [email protected]   End-to-End Example of a complete Hybrid Application – with Live Demo https://azurestocktrader.cloudapp.net/Default.aspx I learn by example. I also like having ready-made, live, functional demos that show the completed solution at work. If you’ve ever wanted to learn how a complex, complete, hybrid application that bridges on-premises systems with cloud-based databases, code, functions and more, this is it. It’s a stock-trading simulator, and you can get everything from the design to the code itself, or you can just play with the application. It’s running on Windows Azure, the actual production servers we use for everything else. Using a Cloud-Based Service https://azureconfigweb.cloudapp.net/Default.aspx Along with that stock-trading application, you have a full demonstration and usable code sample of a web-based service available. If you’re a developer, this is a style of code you need to understand for everything from iPhone development to a full Service-Oriented Architecture (SOA) environment. So check out these resources. I’ll post more from time to time as I run across them. Hopefully they’ll be as useful to you as they are to me. Oh, and if you have a comment on any of the resources, let them know. And if you have any comments about these or any of my entries, feel free to post away. To quote a famous TV Show: “Hello Seattle – I’m listening…”

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  • Some Early Considerations

    - by Chris Massey
    Following on from my previous post, I want to say "thank you" to everyone who has got in touch and got involved – you are pioneers! An update on where we are right now: paper prototypes v1 To be more specific, we’ve picked two of the ideas that seem to have more pros than cons, turned them into Balsamiq mockups, and are getting them fleshed out with realistic content. We’ll initially make these available to the aforementioned pioneers (thank you again), roll in the feedback, and then open up to get more data on what works and what doesn’t. If you’ve got any questions about this (or what we’re working on right now), feel free to ask me in the comments below. I’ve had a few people express an interest in the process we’re going through, and I’m more than happy to share details more frequently as we go along – not least because you, dear reader, will help us stay on target and create something Good. To start with, here’s a quick flashback to bring you all up to speed. A Brief Retrospective As you may already know, we’re creating a new publishing asset specifically focused on providing great content for web developers. We don’t yet know exactly what this thing will look like, or exactly how it will work, but we know we want to create something that is useful different. For my part, I’m seriously excited at the prospect of building a genuinely digital publishing system (as opposed to what most publishing is these days, which is print-style publishing which just happens to be on the web). The main challenge at this point is working out our build-measure-assess loop to speed up our experimental turn-around, and that’ll get better as we run more trials. Of course, there are a few things we’ve been pondering at this early conceptual stage: Do we publishing about heterogeneous technology stacks from day 1, or do we start with ASP.NET (which we’re familiar with) & branch out later? There are challenges with either approach. What publishing "modes" are already being well-handled? For example, the likes of Pluralsight, TekPub, and Treehouse have pretty much nailed video training (debate about price, if you like), and unless we think we can do it faster / better / cheaper (unlikely, for the record), we should leave them to it. Where should we base whatever we create? Should we create a completely new asset under a new name, graft something onto Simple-Talk (like the labs), or just build something directly into Simple-Talk? It sounds trivial, but it does have at least some impact on infrastructure and what how we manage the different types of content we (will) have. Are there any obvious problems or niches that we think could address really well, or should we just throw ideas out and see what readers respond to? What kind of users do we want to provide for? This actually deserves a little bit of unpacking… Why are you here? We currently divide readers into (broadly) the categories: Category 1: I know nothing about X, and I’d like to learn about it. Category 2: I know something about X, but I’d like to learn how to do something specific with it. Category 3: Ah man, I have a problem with X, and I need to fix it now. Now that I think about it, I might also include a 4th class of reader: Category 4: I’m looking for something interesting to engage my brain. These are clearly task-based categorizations, and depending on which task you’re performing when you arrive here, you’re going to need different types of content, or will have specific discovery needs. One of the questions that’s at the back of my mind whenever I consider a new idea is “How many of the categories will this satisfy?” As an example, typical video training is very well suited to categories 1, 2, and 4. StackOverflow is very well suited to category 3, and serves as a sign-posting system to the rest. Clearly it’s not necessary to satisfy every category need to be useful and popular, but being aware of what behavior readers might be exhibiting when they arrive will help us tune our ideas appropriately. < / Flashback > We don’t have clean answers to most of these considerations – they’re things we’re aware of, and each idea we look at is going to be best suited to a different mix of the options I’ve described. Our first experimental loop will be coming full circle in the next few days, so we should start to see how the different possibilities vary between ideas. Free to chime in with questions and suggestions about anything I’ve just brain-dumped, or at any stage as we go along. If you see anything that intrigued or enrages you, or just have an idea you’d like to share, I’d love to hear from you.

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  • PC: Quick Freeze, then BSOD, then forced reboot, then freezes again

    - by cr0z3r
    Lately I have been experiencing a weird issue. My PC will hang for a second and then BSOD - it stays there, so I have to reboot. Once Windows starts again and I'm logged in, after 1-10min it freezes again, this time without BSOD. RECAP: 1 second freeze BSOD, hangs there I have to force-reboot Once PC rebooted, I log back into Windows second freeze between a 1-10min range, no BSOD (alternatively, I get a freeze with a constant sound/noise, no BSOD) I contacted my PC provider, who told me my graphics-card might be flawed (Quadro 4000), so I used a Quadro 2000 that they lend me. The issue still occurred. The issue now seemed to belong to a flawed RAM module. Following my provider's steps, I removed all but the first from the left column and kept using my PC for a week or so without any issues. I then added the bottom-right module, and so on, until all modules were back inside - I had no problems. Now it seemed that a simple take-out-put-back-in of the RAM modules had fixed the issue. However, after a few months, the issue was back. I redid all the RAM-swapping I had done before, and concluded that the lower-right module was flawed. My provider changed it for another, and everything was great until now. My PC froze again for barely a second, hanged on a BSOD, I rebooted it, logged-in to Windows to get a freeze (without BSOD or reboot) 40 seconds later. Something worth noting, is that every time I reboot after the BSOD, it is something within Chrome that freezes my PC (e.g. this time I clicked the "restore" button as Chrome mentioned it had exited unexpectedly - from the previous freeze obviously - and it instantly froze). Finally, the Event Viewer lists 2 critical events in the past hour as "ID: 41, Type: Kernel-Power". PC-Specs: http://i.imgur.com/VZpbr.jpg Previous Dump-files: https://dl.dropbox.com/u/716600/DumpFiles_08_2012.zip I would like to thank anybody in advance for your help. You're great. UPDATE 1: I realized that I did not mention an awkward fact about this issue. After I have gotten the 1-sec freeze followed by a BSOD, after I rebooted because the BSOD hanged, and after I logged back in to get another (this time, eternal) freeze and rebooted once again, the PC does not boot back up. The power-light is on, but my monitor says "no signal", as if the PC wouldn't really be turned on. This truly seems a like a power-related issue, doesn't it? UPDATE 2: I just got a freeze, but without BSOD. My screen froze (while on Chrome, which is starting to seem suspicious to me) with an ongoing sound/noise. I had to force-reboot my PC. I would say this is a graphics-card issue, but this issue also happened when I was using the Quadro 2000 from my provider. UPDATE 3: I just got a BSOD while trying to render something (quite heavy, actually) in 3ds Max 2012. I left the BSOD "running", as it said it was writing dump files to disk. However, the percentage number stayed at 0, so after 15 minutes I force-rebooted. I then used the software WhoCrashed (thank you Dave) which reported the following from the C:\Windows\Memory.dmp file: On Thu 22.11.2012 22:13:45 GMT your computer crashed crash dump file: C:\Windows\memory.dmp uptime: 01:05:27 This was probably caused by the following module: Unknown () Bugcheck code: 0x124 (0x0, 0xFFFFFA80275AC028, 0xF200001F, 0x100B2) Error: WHEA_UNCORRECTABLE_ERROR Bug check description: This bug check indicates that a fatal hardware error has occurred. This bug check uses the error data that is provided by the Windows Hardware Error Architecture (WHEA). This is likely to be caused by a hardware problem problem. This problem might be caused by a thermal issue. A third party driver was identified as the probable root cause of this system error. It is suggested you look for an update for the following driver: Unknown . Google query: Unknown WHEA_UNCORRECTABLE_ERROR

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  • Using Upstart to manage Unicorn w/ rbenv + bundler binstubs w/ ruby-local-exec shebang

    - by codykrieger
    Alright, this is melting my brain. It might have something to do with the fact that I don't understand Upstart as well as I should. Sorry in advance for the long question. I'm trying to use Upstart to manage a Rails app's Unicorn master process. Here is my current /etc/init/app.conf: description "app" start on runlevel [2] stop on runlevel [016] console owner # expect daemon script APP_ROOT=/home/deploy/app PATH=/home/deploy/.rbenv/shims:/home/deploy/.rbenv/bin:$PATH $APP_ROOT/bin/unicorn -c $APP_ROOT/config/unicorn.rb -E production # >> /tmp/upstart.log 2>&1 end script # respawn That works just fine - the Unicorns start up great. What's not great is that the PID detected is not of the Unicorn master, it's of an sh process. That in and of itself isn't so bad, either - if I wasn't using the automagical Unicorn zero-downtime deployment strategy. Because shortly after I send -USR2 to my Unicorn master, a new master spawns up, and the old one dies...and so does the sh process. So Upstart thinks my job has died, and I can no longer restart it with restart or stop it with stop if I want. I've played around with the config file, trying to add -D to the Unicorn line (like this: $APP_ROOT/bin/unicorn -c $APP_ROOT/config/unicorn.rb -E production -D) to daemonize Unicorn, and I added the expect daemon line, but that didn't work either. I've tried expect fork as well. Various combinations of all of those things can cause start and stop to hang, and then Upstart gets really confused about the state of the job. Then I have to restart the machine to fix it. I think Upstart is having problems detecting when/if Unicorn is forking because I'm using rbenv + the ruby-local-exec shebang in my $APP_ROOT/bin/unicorn script. Here it is: #!/usr/bin/env ruby-local-exec # # This file was generated by Bundler. # # The application 'unicorn' is installed as part of a gem, and # this file is here to facilitate running it. # require 'pathname' ENV['BUNDLE_GEMFILE'] ||= File.expand_path("../../Gemfile", Pathname.new(__FILE__).realpath) require 'rubygems' require 'bundler/setup' load Gem.bin_path('unicorn', 'unicorn') Additionally, the ruby-local-exec script looks like this: #!/usr/bin/env bash # # `ruby-local-exec` is a drop-in replacement for the standard Ruby # shebang line: # # #!/usr/bin/env ruby-local-exec # # Use it for scripts inside a project with an `.rbenv-version` # file. When you run the scripts, they'll use the project-specified # Ruby version, regardless of what directory they're run from. Useful # for e.g. running project tasks in cron scripts without needing to # `cd` into the project first. set -e export RBENV_DIR="${1%/*}" exec ruby "$@" So there's an exec in there that I'm worried about. It fires up a Ruby process, which fires up Unicorn, which may or may not daemonize itself, which all happens from an sh process in the first place...which makes me seriously doubt the ability of Upstart to track all of this nonsense. Is what I'm trying to do even possible? From what I understand, the expect stanza in Upstart can only be told (via daemon or fork) to expect a maximum of two forks.

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  • Performance issues when using SSD for a developer notebook (WAMP/LAMP stack)?

    - by András Szepesházi
    I'm a web application developer using my notebook as a standalone development environment (WAMP stack). I just switched from a Core2-duo Vista 32 bit notebook with 2Gb RAM and SATA HDD, to an i5-2520M Win7 64 bit with 4Gb RAM and 128 GB SDD (Corsair P3 128). My initial experience was what I expected, fast boot, quick load of all the applications (Eclipse takes now 5 seconds as opposed to 30s on my old notebook), overall great experience. Then I started to build up my development stack, both as LAMP (using VirtualBox with a debian guest) and WAMP (windows native apache + mysql + php). I wanted to compare those two. This still all worked great out, then I started to pull in my projects to these stacks. And here came the nasty surprise, one of those projects produced a lot worse response times than on my old notebook (that was true for both the VirtualBox and WAMP stack). Apache, php and mysql configurations were practically identical in all environments. I started to do a lot of benchmarking and profiling, and here is what I've found: All general benchmarks (Performance Test 7.0, HDTune Pro, wPrime2 and some more) gave a big advantage to the new notebook. Nothing surprising here. Disc specific tests showed that read/write operations peaked around 380M/160M for the SSD, and all the different sized block operations also performed very well. Started apache performance benchmarking with Apache Benchmark for a small static html file (10 concurrent threads, 500 iterations). Old notebook: min 47ms, median 111ms, max 156ms New WAMP stack: min 71ms, median 135ms, max 296ms New LAMP stack (in VirtualBox): min 6ms, median 46ms, max 175ms Right here I don't get why the native WAMP stack performed so bad, but at least the LAMP environment brought the expected speed. Apache performance measurement for non-cached php content. The php runs a loop of 1000 and generates sha1(uniqid()) inisde. Again, 10 concurrent threads, 500 iterations were used for the benchmark. Old notebook: min 0ms, median 39ms, max 218ms New WAMP stack: min 20ms, median 61ms, max 186ms New LAMP stack (in VirtualBox): min 124ms, median 704ms, max 2463ms What the hell? The new LAMP performed miserably, and even the new native WAMP was outperformed by the old notebook. php + mysql test. The test consists of connecting to a database and reading a single record form a table using INNER JOIN on 3 more (indexed) tables, repeated 100 times within a loop. Databases were identical. 10 concurrent threads, 100 iterations were used for the benchmark. Old notebook: min 1201ms, median 1734ms, max 3728ms New WAMP stack: min 367ms, median 675ms, max 1893ms New LAMP stack (in VirtualBox): min 1410ms, median 3659ms, max 5045ms And the same test with concurrency set to 1 (instead of 10): Old notebook: min 1201ms, median 1261ms, max 1357ms New WAMP stack: min 399ms, median 483ms, max 539ms New LAMP stack (in VirtualBox): min 285ms, median 348ms, max 444ms Strictly for my purposes, as I'm using a self contained development environment (= low concurrency) I could be satisfied with the second test's result. Though I have no idea why the VirtualBox environment performed so bad with higher concurrency. Finally I performed a test of including many php files. The application that I mentioned at the beginning, the one that was performing so bad, has a heavy bootstrap, loads hundreds of small library and configuration files while initializing. So this test does nothing else just includes about 100 files. Concurrency set to 1, 100 iterations: Old notebook: min 140ms, median 168ms, max 406ms New WAMP stack: min 434ms, median 488ms, max 604ms New LAMP stack (in VirtualBox): min 413ms, median 1040ms, max 1921ms Even if I consider that VirtualBox reached those files via shared folders, and that slows things down a bit, I still don't see how could the old notebook outperform so heavily both new configurations. And I think this is the real root of the slow performance, as the application uses even more includes, and the whole bootstrap will occur several times within a page request (for each ajax call, for example). To sum it up, here I am with a brand new high-performance notebook that loads the same page in 20 seconds, that my old notebook can do in 5-7 seconds. Needless to say, I'm not a very happy person right now. Why do you think I experience these poor performance values? What are my options to remedy this situation?

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  • Set up lnux box for hosting a-z

    - by microchasm
    I am in the process of reinstalling the OS on a machine that will be used to host a couple of apps for our business. The apps will be local only; access from external clients will be via vpn only. The prior setup used a hosting control panel (Plesk) for most of the admin, and I was looking at using another similar piece of software for the reinstall - but I figured I should finally learn how it all works. I can do most of the things the software would do for me, but am unclear on the symbiosis of it all. This is all an attempt to further distance myself from the land of Configuration Programmer/Programmer, if at all possible. I can't find a full walkthrough anywhere for what I'm looking for, so I thought I'd put up this question, and if people can help me on the way I will edit this with the answers, and document my progress/pitfalls. Hopefully someday this will help someone down the line. The details: CentOS 5.5 x86_64 httpd: Apache/2.2.3 mysql: 5.0.77 (to be upgraded) php: 5.1 (to be upgraded) The requirements: SECURITY!! Secure file transfer Secure client access (SSL Certs and CA) Secure data storage Virtualhosts/multiple subdomains Local email would be nice, but not critical The Steps: Download latest CentOS DVD-iso (torrent worked great for me). Install CentOS: While going through the install, I checked the Server Components option thinking I was going to be using another Plesk-like admin. In hindsight, considering I've decided to try to go my own way, this probably wasn't the best idea. Basic config: Setup users, networking/ip address etc. Yum update/upgrade. Upgrade PHP: To upgrade PHP to the latest version, I had to look to another repo outside CentOS. IUS looks great and I'm happy I found it! cd /tmp #wget http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/x86_64/epel-release-1-1.ius.el5.noarch.rpm #rpm -Uvh epel-release-1-1.ius.el5.noarch.rpm #wget http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/x86_64/ius-release-1-4.ius.el5.noarch.rpm #rpm -Uvh ius-release-1-4.ius.el5.noarch.rpm yum list | grep -w \.ius\. [will list all packages available in the IUS repo] rpm -qa | grep php [will list installed packages needed to be removed. the installed packages need to be removed before you can install the IUS packages otherwise there will be conflicts] #yum shell >remove php-gd php-cli php-odbc php-mbstring php-pdo php php-xml php-common php-ldap php-mysql php-imap Setting up Remove Process >install php53 php53-mcrypt php53-mysql php53-cli php53-common php53-ldap php53-imap php53-devel >transaction solve >transaction run Leaving Shell #php -v PHP 5.3.2 (cli) (built: Apr 6 2010 18:13:45) This process removes the old version of PHP and installs the latest. To upgrade mysql: Pretty much the same process as above with PHP #/etc/init.d/mysqld stop [OK] rpm -qa | grep mysql [installed mysql packages] #yum shell >remove mysql mysql-server Setting up Remove Process >install mysql51 mysql51-server mysql51-devel >transaction solve >transaction run Leaving Shell #service mysqld start [OK] #mysql -v Server version: 5.1.42-ius Distributed by The IUS Community Project The above upgrade instructions courtesy of IUS wiki: http://wiki.iuscommunity.org/Doc/ClientUsageGuide Create a chroot jail to hold sftp user via rssh. This will force SCP/SFTP and will circumvent traditional FTP server setup. #cd /tmp #wget http://dag.wieers.com/rpm/packages/rssh/rssh-2.3.2-1.2.el5.rf.x86_64.rpm #rpm -ivh rssh-2.3.2-1.2.el5.rf.x86_64.rpm #useradd -m -d /home/dev -s /usr/bin/rssh dev #passwd dev Edit /etc/rssh.conf to grant access to SFTP to rssh users. #vi /etc/rssh.conf Uncomment line allowscp This allows me to connect to the machine via SFTP protocol in Transmit (my FTP program of choice; I'm sure it's similar with other FTP apps). Above instructions for SFTP appropriated (with appreciation!) from http://www.cyberciti.biz/tips/linux-unix-restrict-shell-access-with-rssh.html And this is where I'm at. I will keep editing this as I make progress. Any tips on how to Configure virtual interfaces/ip based virtual hosts for SSL, setting up a CA, or anything else would be appreciated.

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  • MacBook Pro 10.6 losing dns service, network connection still functional if you know the ip address.

    - by Vincent
    MacBook pro connected to a wireless network (not sure about wired) I lose DNS. I still have a functioning connection and as long as I know the ip address of the website, server... for example skype works, ssh name@ipaddress, .... Things can be working properly and then just quit, Once I was im via skype and lost dns skype continued to work. This has happened in multiple locations on private and public networks. What does not work/fix it: Resetting router changing dns server on computer or router connecting to another network removing the airport interface and adding it back flushing dns The only solution seems to be a restart. A solution to this would be great, but any ideas of this to try would be great. Even a sure way to reproduce this would be useful. Maybe related question: But this is most definitely not true for me. "if I refresh enough -- 3 to 4 times --, it will usually pull up the site. " Here are some tests from terminal. Basically this confirms dns in not functioning vmd17:~ vmd$ ping google.com ping: cannot resolve google.com: Unknown host Trace route to google dns, This works vmd17:~ vmd$ /usr/sbin/traceroute -n -w 2 -q 2 -m 30 8.8.8.8 traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 52 byte packets 1 192.168.1.1 5.195 ms 2.519 ms 2 67.172.136.1 31.881 ms 9.177 ms 3 68.85.107.121 12.168 ms 10.003 ms 4 68.86.103.41 12.021 ms 9.594 ms 5 68.86.91.1 16.712 ms 12.837 ms 6 68.86.86.210 29.951 ms 25.826 ms 7 68.86.87.218 29.554 ms 42.894 ms 8 75.149.231.70 68.271 ms 68.362 ms 9 72.14.233.77 141.178 ms 72.14.233.85 82.553 ms 10 72.14.238.243 83.381 ms 82.811 ms 11 72.14.232.213 194.387 ms 72.14.232.215 84.837 ms 12 209.85.253.145 100.294 ms * 13 8.8.8.8 101.689 ms 89.694 ms 208.67.222.22 is the ip address of opendns dns server vmd17:~ vmd$ dig @208.67.222.222 8.8.8.8 ; <<>> DiG 9.6.0-APPLE-P2 <<>> @208.67.222.222 8.8.8.8 ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be reached vmd17:~ vmd$ dig @208.67.222.222 gogle.com vmd17:~ vmd$ dig @208.67.222.222 google.com ; <<>> DiG 9.6.0-APPLE-P2 <<>> @208.67.222.222 google.com ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be reached vmd17:~ vmd$ dig @8.8.8.8 google.com ; <<>> DiG 9.6.0-APPLE-P2 <<>> @8.8.8.8 google.com ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be reached

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  • Asus P8P67 Rev. 3.1 Motherboard issues powering on and saving settings

    - by Scott
    Edit: New Information Have some updated information from the old question below: So basically my issue right now is somewhat similar, but I've been able to rule out a couple of things. I don't think this has anything to do with light on the motherboard. No matter what lights are on/off on the motherboard when the computer is off, they don't affect this issue. The main power LED on the Mobo is always lit when the power supply is turned on, and that's what matters anyway. Even when the main power LED is on, the PC will NOT boot up the first time I hit the power switch. I have to go reset the power supply (make all lights turn off on the Mobo and back on), and THEN hit the power switch. Then everything boots up. Also, the BIOS settings are reset every time this happens. Asus Tech Support told me to try jumping the power with something metal to try and rule out that it's a problem with the connectors getting power, or if it's a problem with the case power switch pins - haven't done that yet though. Any ideas? This is a lot simpler than it was before when I thought it had to do with certain LED indicators for RAM, EPU, etc. Original Question So I built my new desktop just about 3 weeks ago. I've been having a few issues which I think are all related to my motherboard, an Asus P8P67 Revision 3.1, but I'm not 100% sure as this is really the first from-scratch build I've ever done. I've posted these questions on the Asus forums, Asus Tech Support, and the Corsair forums as well as I thought it might have something to do with my power supply at one point. None of these avenues have solved my issue until now completely, so I thought I'd come here to see what you guys think. Here's what's happening: My computer is off, and I go to power it on. I press the power switch on the case (Antec Nine Hundred), and nothing seems to happen. Upon further inspection, I see that what this actually does is simply turn on the EPU LED on my motherboard, but doesn't actually boot anything up. I then have to go and flip the main power switch on the power supply off and back on. What this does is turn off all lights on the Motherboard after a few seconds, and turn them all back on (including the EPU LED that was off before I hit the power switch the first time). Now, hitting the power switch works. The machine boots up fine, and starts going through the boot up process. As a side note: My Motherboard is set to "Force BIOS", and every single time I change this to do the opposite, the next time my computer boots up that change reverts itself. I think this may be due to the fact that I am doing the hard reset on the power supply each time, but I'm not sure. I had thought that the Motherboard would keep its BIOS settings unless you did something to the Mobo itself - so this may be a related issue, or something else completely. That's basically it. Once it's on, it's on. It works fine, recognizes all of my hardware, and runs great. All fans/lights in the case work great, and I'm getting standard readings. The next time I go to shut the computer down however, I can expect the same exact process getting it up and running, including being forced to go into BIOS and exit again before I can load Windows. Another side note: If I power on my computer using the power switch DIRECTLY after shutting it down, it powers right back on (I think this is because the EPU LED light doesn't have time to turn off). It looks as if as long as the EPU LED is lit up on the motherboard before I hit the power switch on the case, the thing will boot up fine (although this doesn't explain the "Force BIOS" issue, at least it's something). Any ideas? Thanks guys. P.S. - System Specs Asus P8P67 Rev. 3.1 Motherboard Intel Core i7 2600K Processor 16GB (4x4GB) G-Skill 1600 RAM NVIDIA EVGA GTX 570 Video Card Crucial 128GB SSD HD Corsair 850W Power Supply Seagate 2TB HDD

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