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  • #OOW 2012 : IaaS, Private Cloud, Multitenant Database, and X3H2M2

    - by Eric Bezille
    The title of this post is a summary of the 4 announcements made by Larry Ellison today, during the opening session of Oracle Open World 2012... To know what's behind X3H2M2, you will have to wait a little, as I will go in order, beginning with the IaaS - Infrastructure as a Service - announcement. Oracle IaaS goes Public... and Private... Starting in 2004 with Fusion development, Oracle Cloud was launch last year to provide not only SaaS Application, based on standard development, but also the underlying PaaS, required to build the specifics, and required interconnections between applications, in and outside of the Cloud. Still, to cover the end-to-end Cloud  Services spectrum, we had to provide an Infrastructure as a Service, leveraging our Servers, Storage, OS, and Virtualization Technologies, all "Engineered Together". This Cloud Infrastructure, was already available for our customers to build rapidly their own Private Cloud either on SPARC/Solaris or x86/Linux... The second announcement made today bring that proposition a big step further : for cautious customers (like Banks, or sensible industries) who would like to benefits from the Cloud value of "as a Service", but don't want their Data out in the Cloud... We propose to them to operate the same systems, Exadata, Exalogic & SuperCluster, that are providing our Public Cloud Infrastructure, behind their firewall, in a Private Cloud model. Oracle 12c Multitenant Database This is also a major announcement made today, on what's coming with Oracle Database 12c : the ability to consolidate multiple databases with no extra additional  cost especially in terms of memory needed on the server node, which is often THE consolidation limiting factor. The principle could be compare to Solaris Zones, where, you will have a Database Container, who is "owning" the memory and Database background processes, and "Pluggable" Database in this Database Container. This particular feature is a strong compelling event to evaluate rapidly Oracle Database 12c once it will be available, as this is major step forward into true Database consolidation with Multitenancy on a shared (optimized) infrastructure. X3H2M2, enabling the new Exadata X3 in-Memory Database Here we are :  X3H2M2 stands for X3 (the new version of Exadata announced also today) Heuristic Hierarchical Mass Memory, providing the capability to keep most if not all the Data in the memory cache hierarchy. Of course, this is the major software enhancement of the new X3 Exadata machine, but as this is a software, our current customers would be able to benefit from it on their existing systems by upgrading to the new release. But that' not the only thing that we did with X3, at the same time we have upgraded everything : the CPUs, adding more cores per server node (16 vs. 12, with the arrival of Intel E5 / Sandy Bridge), the memory with 512GB memory as well per node,  and the new Flash Fire card, bringing now up to 22 TB of Flash cache. All of this 4TB of RAM + 22TB of Flash being use cleverly not only for read but also for write by the X3H2M2 algorithm... making a very big difference compare to traditional storage flash extension. But what does those extra performances brings to you on an already very efficient system: double your performances compare to the fastest storage array on the market today (including flash) and divide you storage price x10 at the same time... Something to consider closely this days... Especially that we also announced the availability of a new Exadata X3-2 8th rack : a good starting point. As you have seen a major opening for this year again with true innovation. But that was not the only thing that we saw today, as before Larry's talk, Fujitsu did introduce more in deep the up coming new SPARC processor, that they are co-developing with us. And as such Andrew Mendelsohn - Senior Vice President Database Server Technologies came on stage to explain that the next step after I/O optimization for Database with Exadata, was to accelerate the Database at execution level by bringing functions in the SPARC processor silicium. All in all, to process more and more Data... The big theme of the day... and of the Oracle User Groups Conferences that were also happening today and where I had the opportunity to attend some interesting sessions on practical use cases of Big Data one in Finances and Fraud profiling and the other one on practical deployment of Oracle Exalytics for Data Analytics. In conclusion, one picture to try to size Oracle Open World ... and you can understand why, with such a rich content... and this only the first day !

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  • Cocos2d: Moving background on update: offsett issue

    - by mm24
    working with Objective C, iOS and Cocos2d I am developing a vertical scrolling shooter game for iPhone (retina display models with 640 width x 960 height pixel resolution). My basic algorithm works as following: I create two instances of an image that has exactly 640 width x 960 height pixel of resolution, which we will call imageA and imageB I then set the two imags with exactly 480.0f of offset from each other, as the screenSize of a CCScene is set by default to 480.0f. At each update method call I move the two images by the same value. I make sure that their offsett stays to 480.0f However when running the game I see a 1 pixel height line between the two images. This literally bugs me and would like to adjust this. What am I doing wrong? This is a zoom in on the background when the "offsett line" is visible. The white line you can see divides the two background images and is not meant to exist as both images are completely black :): If I change the yPositionOfSecondElement value to 479.0f until the first loop the two images overlap correctly, but as soon as the loop starts the two images starts having an offsett of -1.0f. Here is the initialization code: -(void) init { //... screenHeight = 480.0f; yPositionOfSecondElement= screenHeight;//I tried subtracting an offsett of -1 but eventually the image would go wrong again yPositionOfFirstElement = 0.0f; loopedBackgroundImageInstanceA = [BackgroundLoopedImage loopImageForLevel:levelName]; loopedBackgroundImageInstanceA.anchorPoint = CGPointMake(0.5f, 0.0f); loopedBackgroundImageInstanceA.position = CGPointMake(160.0f, yPositionOfFirstElement); [node addChild:loopedBackgroundImageInstanceA z:zLevelBackground]; //loopedBackgroundImageInstanceA.color= ccRED; loopedBackgroundImageInstanceB = [BackgroundLoopedImage loopImageForLevel:levelName]; loopedBackgroundImageInstanceB.anchorPoint = CGPointMake(0.5f, 0.0f); loopedBackgroundImageInstanceB.position = CGPointMake(160.0f, yPositionOfSecondElement); [node addChild:loopedBackgroundImageInstanceB z:zLevelBackground]; //.... } And here is the move code called at each update: -(void) moveBackgroundSprites:(BackgroundLoopedImage*)imageA :(BackgroundLoopedImage*)imageB :(ccTime)delta { isEligibleToMove=false; //This is done to avoid rounding errors float yStep = delta * [GameController sharedGameController].currentBackgroundSpeed; NSString* formattedNumber = [NSString stringWithFormat:@"%.02f", yStep]; yStep = atof([formattedNumber UTF8String]); //First should adjust position of images [self adjustPosition:imageA :imageB]; //The can get the actual image position CGPoint posA = imageA.position; CGPoint posB = imageB.position; //Here could verify if the checksum is equal to the required difference (should be 479.0f) if (![self verifyCheckSum:posA :posB]) { CCLOG(@"does not comply A"); } //At this stage can compute the hypotetical new position CGPoint newPosA = CGPointMake(posA.x, posA.y - yStep); CGPoint newPosB = CGPointMake(posB.x, posB.y - yStep); // Reposition stripes when they're out of bounds if (newPosA.y <= -yPositionOfSecondElement) { newPosA.y = yPositionOfSecondElement; [imageA shuffle]; if (timeElapsed>=endTime && hasReachedEndLevel==FALSE) { hasReachedEndLevel=TRUE; shouldMoveImageEnd=TRUE; } } else if (newPosB.y <= -yPositionOfSecondElement) { newPosB.y = yPositionOfSecondElement; [imageB shuffle]; if (timeElapsed>=endTime && hasReachedEndLevel==FALSE) { hasReachedEndLevel=TRUE; shouldMoveImageEnd=TRUE; } } //Here should verify that the check sum is equal to 479.0f if (![self verifyCheckSum:posA :posB]) { CCLOG(@"does not comply B"); } imageA.position = newPosA; imageB.position = newPosB; //Here could verify that the check sum is equal to 479.0f if (![self verifyCheckSum:posA :posB]) { CCLOG(@"does not comply C"); } isEligibleToMove=true; } -(BOOL) verifyCheckSum:(CGPoint)posA :(CGPoint)posB { BOOL comply = false; float sum = 0.0f; if (posA.y > posB.y) { sum = posA.y - posB.y; } else if (posB.y > posA.y){ sum = posB.y - posA.y; } else{ return false; } if (sum!=yPositionOfSecondElement) { comply= false; } else{ comply=true; } return comply; } And here is what happens on the update: if(shouldMoveImageA && shouldMoveImageB) { if (isEligibleToMove) { [self moveBackgroundSprites:loopedBackgroundImageInstanceA :loopedBackgroundImageInstanceB :delta]; } Forget about shouldMoveImageA and shouldMoveImageB, this is just for when the background reaches the end of level, this works.

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  • How do I make A* check all diagonal and orthogonal directions?

    - by Munezane
    I'm making a turn-based tactical game and I'm trying to implement the A* algorithm. I've been following a tutorial and got to this point, but my characters can't move diagonally up and left. Can anyone help me with this? The return x and y are int pointers which the characters are using to move towards the target. void level::aStar(int startx, int starty, int targetx, int targety, int* returnx, int* returny) { aStarGridSquare* currentSquare = new aStarGridSquare(); aStarGridSquare* startSquare = new aStarGridSquare(); aStarGridSquare* targetSquare = new aStarGridSquare(); aStarGridSquare* adjacentSquare = new aStarGridSquare(); aStarOpenList.clear(); for(unsigned int i=0; i<aStarGridSquareList.size(); i++) { aStarGridSquareList[i]->open=false; aStarGridSquareList[i]->closed=false; } startSquare=getaStarGridSquare(startx, starty); targetSquare=getaStarGridSquare(targetx, targety); if(startSquare==targetSquare) { *returnx=startx; *returny=starty; return; } startSquare->CostFromStart=0; startSquare->CostToTraverse=0; startSquare->parent = NULL; currentSquare=startSquare; aStarOpenList.push_back(currentSquare); while(currentSquare!=targetSquare && aStarOpenList.size()>0) { //unsigned int totalCostEstimate=aStarOpenList[0]->TotalCostEstimate; //currentSquare=aStarOpenList[0]; for(unsigned int i=0; i<aStarOpenList.size(); i++) { if(aStarOpenList.size()>1) { for(unsigned int j=1; j<aStarOpenList.size()-1; j++) { if(aStarOpenList[i]->TotalCostEstimate<aStarOpenList[j]->TotalCostEstimate) { currentSquare=aStarOpenList[i]; } else { currentSquare=aStarOpenList[j]; } } } else { currentSquare = aStarOpenList[i]; } } currentSquare->closed=true; currentSquare->open=false; for(unsigned int i=0; i<aStarOpenList.size(); i++) { if(aStarOpenList[i]==currentSquare) { aStarOpenList.erase(aStarOpenList.begin()+i); } } for(unsigned int i = currentSquare->blocky - 32; i <= currentSquare->blocky + 32; i+=32) { for(unsigned int j = currentSquare->blockx - 32; j<= currentSquare->blockx + 32; j+=32) { adjacentSquare=getaStarGridSquare(j/32, i/32); if(adjacentSquare!=NULL) { if(adjacentSquare->blocked==false && adjacentSquare->closed==false) { if(adjacentSquare->open==false) { adjacentSquare->parent=currentSquare; if(currentSquare->parent!=NULL) { currentSquare->CostFromStart = currentSquare->parent->CostFromStart + currentSquare->CostToTraverse + startSquare->CostFromStart; } else { currentSquare->CostFromStart=0; } adjacentSquare->CostFromStart =currentSquare->CostFromStart + adjacentSquare->CostToTraverse;// adjacentSquare->parent->CostFromStart + adjacentSquare->CostToTraverse; //currentSquare->CostToEndEstimate = abs(currentSquare->blockx - targetSquare->blockx) + abs(currentSquare->blocky - targetSquare->blocky); //currentSquare->TotalCostEstimate = currentSquare->CostFromStart + currentSquare->CostToEndEstimate; adjacentSquare->open = true; adjacentSquare->CostToEndEstimate=abs(adjacentSquare->blockx- targetSquare->blockx) + abs(adjacentSquare->blocky-targetSquare->blocky); adjacentSquare->TotalCostEstimate = adjacentSquare->CostFromStart+adjacentSquare->CostToEndEstimate; //adjacentSquare->open=true;*/ aStarOpenList.push_back(adjacentSquare); } else { if(adjacentSquare->parent->CostFromStart > currentSquare->CostFromStart) { adjacentSquare->parent=currentSquare; if(currentSquare->parent!=NULL) { currentSquare->CostFromStart = currentSquare->parent->CostFromStart + currentSquare->CostToTraverse + startSquare->CostFromStart; } else { currentSquare->CostFromStart=0; } adjacentSquare->CostFromStart =currentSquare->CostFromStart + adjacentSquare->CostToTraverse;// adjacentSquare->parent->CostFromStart + adjacentSquare->CostToTraverse; //currentSquare->CostToEndEstimate = abs(currentSquare->blockx - targetSquare->blockx) + abs(currentSquare->blocky - targetSquare->blocky); //currentSquare->TotalCostEstimate = currentSquare->CostFromStart + currentSquare->CostToEndEstimate; adjacentSquare->CostFromStart = adjacentSquare->parent->CostFromStart + adjacentSquare->CostToTraverse; adjacentSquare->CostToEndEstimate=abs(adjacentSquare->blockx - targetSquare->blockx) + abs(adjacentSquare->blocky - targetSquare->blocky); adjacentSquare->TotalCostEstimate = adjacentSquare->CostFromStart+adjacentSquare->CostToEndEstimate; } } } } } } } if(aStarOpenList.size()==0)//if empty { *returnx =startx; *returny =starty; return; } else { for(unsigned int i=0; i< aStarOpenList.size(); i++) { if(currentSquare->parent==NULL) { //int tempX = targetSquare->blockx; //int tempY = targetSquare->blocky; *returnx=targetSquare->blockx; *returny=targetSquare->blocky; break; } else { currentSquare=currentSquare->parent; } } } }

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  • Contricted A* problem

    - by Ragekit
    I've got a little problem with an A* algorithm that I need to constrict a little bit. Basically : I use an A* to find the shortest path between 2 randomly placed room in 3D space, and then build a corridor between them. The problem I found is that sometimes it makes chimney like corridors that are not ideal, so I constrict the A* so that if the last movement was up or down, you go sideways. Everything is fine, but in some corner cases, it fails to find a path (when there is obviously one). Like here between the blue and red dot : (i'm in unity btw, but i don't think it matters) Here is the code of the actual A* (a bit long, and some redundency) while(current != goal) { //add stair up / stair down foreach(Node<GridUnit> test in current.Neighbors) { if(!test.Data.empty && test != goal) continue; //bug at arrival; if(test == goal && penul !=null) { Vector3 currentDiff = current.Data.bounds.center - test.Data.bounds.center; if(!Mathf.Approximately(currentDiff.y,0)) { //wanna drop on the last if(!coplanar(test.Data.bounds.center,current.Data.bounds.center,current.Data.parentUnit.bounds.center,to.Data.bounds.center)) { continue; } else { if(Mathf.Approximately(to.Data.bounds.center.x, current.Data.parentUnit.bounds.center.x) && Mathf.Approximately(to.Data.bounds.center.z, current.Data.parentUnit.bounds.center.z)) { continue; } } } } if(current.Data.parentUnit != null) { Vector3 previousDiff = current.Data.parentUnit.bounds.center - current.Data.bounds.center; Vector3 currentDiff = current.Data.bounds.center - test.Data.bounds.center; if(!Mathf.Approximately(previousDiff.y,0)) { if(!Mathf.Approximately(currentDiff.y,0)) { //you wanna drop now : continue; } if(current.Data.parentUnit.parentUnit != null) { if(!coplanar(test.Data.bounds.center,current.Data.bounds.center,current.Data.parentUnit.bounds.center,current.Data.parentUnit.parentUnit.bounds.center)) { continue; }else { if(Mathf.Approximately(test.Data.bounds.center.x, current.Data.parentUnit.parentUnit.bounds.center.x) && Mathf.Approximately(test.Data.bounds.center.z, current.Data.parentUnit.parentUnit.bounds.center.z)) { continue; } } } } } g = current.Data.g + HEURISTIC(current.Data,test.Data); h = HEURISTIC(test.Data,goal.Data); f = g + h; if(open.Contains(test) || closed.Contains(test)) { if(test.Data.f > f) { //found a shorter path going passing through that point test.Data.f = f; test.Data.g = g; test.Data.h = h; test.Data.parentUnit = current.Data; } } else { //jamais rencontré test.Data.f = f; test.Data.h = h; test.Data.g = g; test.Data.parentUnit = current.Data; open.Add(test); } } closed.Add (current); if(open.Count == 0) { Debug.Log("nothingfound"); //nothing more to test no path found, stay to from; List<GridUnit> r = new List<GridUnit>(); r.Add(from.Data); return r; } //sort open from small to biggest travel cost open.Sort(delegate(Node<GridUnit> x, Node<GridUnit> y) { return (int)(x.Data.f-y.Data.f); }); //get the smallest travel cost node; Node<GridUnit> smallest = open[0]; current = smallest; open.RemoveAt(0); } //build the path going backward; List<GridUnit> ret = new List<GridUnit>(); if(penul != null) { ret.Insert(0,to.Data); } GridUnit cur = goal.Data; ret.Insert(0,cur); do{ cur = cur.parentUnit; ret.Insert(0,cur); } while(cur != from.Data); return ret; You see at the start of the foreach i constrict the A* like i said. If you have any insight it would be cool. Thanks

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  • Convert Java program to C

    - by imicrothinking
    I need a bit of guidance with writing a C program...a bit of quick background as to my level, I've programmed in Java previously, but this is my first time programming in C, and we've been tasked to translate a word count program from Java to C that consists of the following: Read a file from memory Count the words in the file For each occurrence of a unique word, keep a word counter variable Print out the top ten most frequent words and their corresponding occurrences Here's the source program in Java: package lab0; import java.io.File; import java.io.FileReader; import java.util.ArrayList; import java.util.Calendar; import java.util.Collections; public class WordCount { private ArrayList<WordCountNode> outputlist = null; public WordCount(){ this.outputlist = new ArrayList<WordCountNode>(); } /** * Read the file into memory. * * @param filename name of the file. * @return content of the file. * @throws Exception if the file is too large or other file related exception. */ public char[] readFile(String filename) throws Exception{ char [] result = null; File file = new File(filename); long size = file.length(); if (size > Integer.MAX_VALUE){ throw new Exception("File is too large"); } result = new char[(int)size]; FileReader reader = new FileReader(file); int len, offset = 0, size2read = (int)size; while(size2read > 0){ len = reader.read(result, offset, size2read); if(len == -1) break; size2read -= len; offset += len; } return result; } /** * Make article word by word. * * @param article the content of file to be counted. * @return string contains only letters and "'". */ private enum SPLIT_STATE {IN_WORD, NOT_IN_WORD}; /** * Go through article, find all the words and add to output list * with their count. * * @param article the content of the file to be counted. * @return words in the file and their counts. */ public ArrayList<WordCountNode> countWords(char[] article){ SPLIT_STATE state = SPLIT_STATE.NOT_IN_WORD; if(null == article) return null; char curr_ltr; int curr_start = 0; for(int i = 0; i < article.length; i++){ curr_ltr = Character.toUpperCase( article[i]); if(state == SPLIT_STATE.IN_WORD){ article[i] = curr_ltr; if ((curr_ltr < 'A' || curr_ltr > 'Z') && curr_ltr != '\'') { article[i] = ' '; //printf("\nthe word is %s\n\n",curr_start); if(i - curr_start < 0){ System.out.println("i = " + i + " curr_start = " + curr_start); } addWord(new String(article, curr_start, i-curr_start)); state = SPLIT_STATE.NOT_IN_WORD; } }else{ if (curr_ltr >= 'A' && curr_ltr <= 'Z') { curr_start = i; article[i] = curr_ltr; state = SPLIT_STATE.IN_WORD; } } } return outputlist; } /** * Add the word to output list. */ public void addWord(String word){ int pos = dobsearch(word); if(pos >= outputlist.size()){ outputlist.add(new WordCountNode(1L, word)); }else{ WordCountNode tmp = outputlist.get(pos); if(tmp.getWord().compareTo(word) == 0){ tmp.setCount(tmp.getCount() + 1); }else{ outputlist.add(pos, new WordCountNode(1L, word)); } } } /** * Search the output list and return the position to put word. * @param word is the word to be put into output list. * @return position in the output list to insert the word. */ public int dobsearch(String word){ int cmp, high = outputlist.size(), low = -1, next; // Binary search the array to find the key while (high - low > 1) { next = (high + low) / 2; // all in upper case cmp = word.compareTo((outputlist.get(next)).getWord()); if (cmp == 0) return next; else if (cmp < 0) high = next; else low = next; } return high; } public static void main(String args[]){ // handle input if (args.length == 0){ System.out.println("USAGE: WordCount <filename> [Top # of results to display]\n"); System.exit(1); } String filename = args[0]; int dispnum; try{ dispnum = Integer.parseInt(args[1]); }catch(Exception e){ dispnum = 10; } long start_time = Calendar.getInstance().getTimeInMillis(); WordCount wordcount = new WordCount(); System.out.println("Wordcount: Running..."); // read file char[] input = null; try { input = wordcount.readFile(filename); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); System.exit(1); } // count all word ArrayList<WordCountNode> result = wordcount.countWords(input); long end_time = Calendar.getInstance().getTimeInMillis(); System.out.println("wordcount: completed " + (end_time - start_time)/1000000 + "." + (end_time - start_time)%1000000 + "(s)"); System.out.println("wordsort: running ..."); start_time = Calendar.getInstance().getTimeInMillis(); Collections.sort(result); end_time = Calendar.getInstance().getTimeInMillis(); System.out.println("wordsort: completed " + (end_time - start_time)/1000000 + "." + (end_time - start_time)%1000000 + "(s)"); Collections.reverse(result); System.out.println("\nresults (TOP "+ dispnum +" from "+ result.size() +"):\n" ); // print out result String str ; for (int i = 0; i < result.size() && i < dispnum; i++){ if(result.get(i).getWord().length() > 15) str = result.get(i).getWord().substring(0, 14); else str = result.get(i).getWord(); System.out.println(str + " - " + result.get(i).getCount()); } } public class WordCountNode implements Comparable{ private String word; private long count; public WordCountNode(long count, String word){ this.count = count; this.word = word; } public String getWord() { return word; } public void setWord(String word) { this.word = word; } public long getCount() { return count; } public void setCount(long count) { this.count = count; } public int compareTo(Object arg0) { // TODO Auto-generated method stub WordCountNode obj = (WordCountNode)arg0; if( count - obj.getCount() < 0) return -1; else if( count - obj.getCount() == 0) return 0; else return 1; } } } Here's my attempt (so far) in C: #include <stdio.h> #include <stdlib.h> #include <stdbool.h> #include <string.h> // Read in a file FILE *readFile (char filename[]) { FILE *inputFile; inputFile = fopen (filename, "r"); if (inputFile == NULL) { printf ("File could not be opened.\n"); exit (EXIT_FAILURE); } return inputFile; } // Return number of words in an array int wordCount (FILE *filePointer, char filename[]) {//, char *words[]) { // count words int count = 0; char temp; while ((temp = getc(filePointer)) != EOF) { //printf ("%c", temp); if ((temp == ' ' || temp == '\n') && (temp != '\'')) count++; } count += 1; // counting method uses space AFTER last character in word - the last space // of the last character isn't counted - off by one error // close file fclose (filePointer); return count; } // Print out the frequencies of the 10 most frequent words in the console int main (int argc, char *argv[]) { /* Step 1: Read in file and check for errors */ FILE *filePointer; filePointer = readFile (argv[1]); /* Step 2: Do a word count to prep for array size */ int count = wordCount (filePointer, argv[1]); printf ("Number of words is: %i\n", count); /* Step 3: Create a 2D array to store words in the file */ // open file to reset marker to beginning of file filePointer = fopen (argv[1], "r"); // store words in character array (each element in array = consecutive word) char allWords[count][100]; // 100 is an arbitrary size - max length of word int i,j; char temp; for (i = 0; i < count; i++) { for (j = 0; j < 100; j++) { // labels are used with goto statements, not loops in C temp = getc(filePointer); if ((temp == ' ' || temp == '\n' || temp == EOF) && (temp != '\'') ) { allWords[i][j] = '\0'; break; } else { allWords[i][j] = temp; } printf ("%c", allWords[i][j]); } printf ("\n"); } // close file fclose (filePointer); /* Step 4: Use a simple selection sort algorithm to sort 2D char array */ // PStep 1: Compare two char arrays, and if // (a) c1 > c2, return 2 // (b) c1 == c2, return 1 // (c) c1 < c2, return 0 qsort(allWords, count, sizeof(char[][]), pstrcmp); /* int k = 0, l = 0, m = 0; char currentMax, comparedElement; int max; // the largest element in the current 2D array int elementToSort = 0; // elementToSort determines the element to swap with starting from the left // Outer a iterates through number of swaps needed for (k = 0; k < count - 1; k++) { // times of swaps max = k; // max element set to k // Inner b iterates through successive elements to fish out the largest element for (m = k + 1; m < count - k; m++) { currentMax = allWords[k][l]; comparedElement = allWords[m][l]; // Inner c iterates through successive chars to set the max vars to the largest for (l = 0; (currentMax != '\0' || comparedElement != '\0'); l++) { if (currentMax > comparedElement) break; else if (currentMax < comparedElement) { max = m; currentMax = allWords[m][l]; break; } else if (currentMax == comparedElement) continue; } } // After max (count and string) is determined, perform swap with temp variable char swapTemp[1][20]; int y = 0; do { swapTemp[0][y] = allWords[elementToSort][y]; allWords[elementToSort][y] = allWords[max][y]; allWords[max][y] = swapTemp[0][y]; } while (swapTemp[0][y++] != '\0'); elementToSort++; } */ int a, b; for (a = 0; a < count; a++) { for (b = 0; (temp = allWords[a][b]) != '\0'; b++) { printf ("%c", temp); } printf ("\n"); } // Copy rows to different array and print results /* char arrayCopy [count][20]; int ac, ad; char tempa; for (ac = 0; ac < count; ac++) { for (ad = 0; (tempa = allWords[ac][ad]) != '\0'; ad++) { arrayCopy[ac][ad] = tempa; printf("%c", arrayCopy[ac][ad]); } printf("\n"); } */ /* Step 5: Create two additional arrays: (a) One in which each element contains unique words from char array (b) One which holds the count for the corresponding word in the other array */ /* Step 6: Sort the count array in decreasing order, and print the corresponding array element as well as word count in the console */ return 0; } // Perform housekeeping tasks like freeing up memory and closing file I'm really stuck on the selection sort algorithm. I'm currently using 2D arrays to represent strings, and that worked out fine, but when it came to sorting, using three level nested loops didn't seem to work, I tried to use qsort instead, but I don't fully understand that function as well. Constructive feedback and criticism greatly welcome (...and needed)!

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  • Increasing efficiency of N-Body gravity simulation

    - by Postman
    I'm making a space exploration type game, it will have many planets and other objects that will all have realistic gravity. I currently have a system in place that works, but if the number of planets goes above 70, the FPS decreases an practically exponential rates. I'm making it in C# and XNA. My guess is that I should be able to do gravity calculations between 100 objects without this kind of strain, so clearly my method is not as efficient as it should be. I have two files, Gravity.cs and EntityEngine.cs. Gravity manages JUST the gravity calculations, EntityEngine creates an instance of Gravity and runs it, along with other entity related methods. EntityEngine.cs public void Update() { foreach (KeyValuePair<string, Entity> e in Entities) { e.Value.Update(); } gravity.Update(); } (Only relevant piece of code from EntityEngine, self explanatory. When an instance of Gravity is made in entityEngine, it passes itself (this) into it, so that gravity can have access to entityEngine.Entities (a dictionary of all planet objects)) Gravity.cs namespace ExplorationEngine { public class Gravity { private EntityEngine entityEngine; private Vector2 Force; private Vector2 VecForce; private float distance; private float mult; public Gravity(EntityEngine e) { entityEngine = e; } public void Update() { //First loop foreach (KeyValuePair<string, Entity> e in entityEngine.Entities) { //Reset the force vector Force = new Vector2(); //Second loop foreach (KeyValuePair<string, Entity> e2 in entityEngine.Entities) { //Make sure the second value is not the current value from the first loop if (e2.Value != e.Value ) { //Find the distance between the two objects. Because Fg = G * ((M1 * M2) / r^2), using Vector2.Distance() and then squaring it //is pointless and inefficient because distance uses a sqrt, squaring the result simple cancels that sqrt. distance = Vector2.DistanceSquared(e2.Value.Position, e.Value.Position); //This makes sure that two planets do not attract eachother if they are touching, completely unnecessary when I add collision, //For now it just makes it so that the planets are not glitchy, performance is not significantly improved by removing this IF if (Math.Sqrt(distance) > (e.Value.Texture.Width / 2 + e2.Value.Texture.Width / 2)) { //Calculate the magnitude of Fg (I'm using my own gravitational constant (G) for the sake of time (I know it's 1 at the moment, but I've been changing it) mult = 1.0f * ((e.Value.Mass * e2.Value.Mass) / distance); //Calculate the direction of the force, simply subtracting the positions and normalizing works, this fixes diagonal vectors //from having a larger value, and basically makes VecForce a direction. VecForce = e2.Value.Position - e.Value.Position; VecForce.Normalize(); //Add the vector for each planet in the second loop to a force var. Force = Vector2.Add(Force, VecForce * mult); //I have tried Force += VecForce * mult, and have not noticed much of an increase in speed. } } } //Add that force to the first loop's planet's position (later on I'll instead add to acceleration, to account for inertia) e.Value.Position += Force; } } } } I have used various tips (about gravity optimizing, not threading) from THIS question (that I made yesterday). I've made this gravity method (Gravity.Update) as efficient as I know how to make it. This O(N^2) algorithm still seems to be eating up all of my CPU power though. Here is a LINK (google drive, go to File download, keep .Exe with the content folder, you will need XNA Framework 4.0 Redist. if you don't already have it) to the current version of my game. Left click makes a planet, right click removes the last planet. Mouse moves the camera, scroll wheel zooms in and out. Watch the FPS and Planet Count to see what I mean about performance issues past 70 planets. (ALL 70 planets must be moving, I've had 100 stationary planets and only 5 or so moving ones while still having 300 fps, the issue arises when 70+ are moving around) After 70 planets are made, performance tanks exponentially. With < 70 planets, I get 330 fps (I have it capped at 300). At 90 planets, the FPS is about 2, more than that and it sticks around at 0 FPS. Strangely enough, when all planets are stationary, the FPS climbs back up to around 300, but as soon as something moves, it goes right back down to what it was, I have no systems in place to make this happen, it just does. I considered multithreading, but that previous question I asked taught me a thing or two, and I see now that that's not a viable option. I've also thought maybe I could do the calculations on my GPU instead, though I don't think it should be necessary. I also do not know how to do this, it is not a simple concept and I want to avoid it unless someone knows a really noob friendly simple way to do it that will work for an n-body gravity calculation. (I have an NVidia gtx 660) Lastly I've considered using a quadtree type system. (Barnes Hut simulation) I've been told (in the previous question) that this is a good method that is commonly used, and it seems logical and straightforward, however the implementation is way over my head and I haven't found a good tutorial for C# yet that explains it in a way I can understand, or uses code I can eventually figure out. So my question is this: How can I make my gravity method more efficient, allowing me to use more than 100 objects (I can render 1000 planets with constant 300+ FPS without gravity calculations), and if I can't do much to improve performance (including some kind of quadtree system), could I use my GPU to do the calculations?

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  • Data Source Security Part 4

    - by Steve Felts
    So far, I have covered Client Identity and Oracle Proxy Session features, with WLS or database credentials.  This article will cover one more feature, Identify-based pooling.  Then, there is one more topic to cover - how these options play with transactions.Identity-based Connection Pooling An identity based pool creates a heterogeneous pool of connections.  This allows applications to use a JDBC connection with a specific DBMS credential by pooling physical connections with different DBMS credentials.  The DBMS credential is based on either the WebLogic user mapped to a database user or the database user directly, based on the “use database credentials” setting as described earlier. Using this feature enabled with “use database credentials” enabled seems to be what is proposed in the JDBC standard, basically a heterogeneous pool with users specified by getConnection(user, password). The allocation of connections is more complex if Enable Identity Based Connection Pooling attribute is enabled on the data source.  When an application requests a database connection, the WebLogic Server instance selects an existing physical connection or creates a new physical connection with requested DBMS identity. The following section provides information on how heterogeneous connections are created:1. At connection pool initialization, the physical JDBC connections based on the configured or default “initial capacity” are created with the configured default DBMS credential of the data source.2. An application tries to get a connection from a data source.3a. If “use database credentials” is not enabled, the user specified in getConnection is mapped to a DBMS credential, as described earlier.  If the credential map doesn’t have a matching user, the default DBMS credential is used from the datasource descriptor.3b. If “use database credentials” is enabled, the user and password specified in getConnection are used directly.4. The connection pool is searched for a connection with a matching DBMS credential.5. If a match is found, the connection is reserved and returned to the application.6. If no match is found, a connection is created or reused based on the maximum capacity of the pool: - If the maximum capacity has not been reached, a new connection is created with the DBMS credential, reserved, and returned to the application.- If the pool has reached maximum capacity, based on the least recently used (LRU) algorithm, a physical connection is selected from the pool and destroyed. A new connection is created with the DBMS credential, reserved, and returned to the application. It should be clear that finding a matching connection is more expensive than a homogeneous pool.  Destroying a connection and getting a new one is very expensive.  If you can use a normal homogeneous pool or one of the light-weight options (client identity or an Oracle proxy connection), those should be used instead of identity based pooling. Regardless of how physical connections are created, each physical connection in the pool has its own DBMS credential information maintained by the pool. Once a physical connection is reserved by the pool, it does not change its DBMS credential even if the current thread changes its WebLogic user credential and continues to use the same connection. To configure this feature, select Enable Identity Based Connection Pooling.  See http://docs.oracle.com/cd/E24329_01/apirefs.1211/e24401/taskhelp/jdbc/jdbc_datasources/EnableIdentityBasedConnectionPooling.html  "Enable identity-based connection pooling for a JDBC data source" in Oracle WebLogic Server Administration Console Help. You must make the following changes to use Logging Last Resource (LLR) transaction optimization with Identity-based Pooling to get around the problem that multiple users will be accessing the associated transaction table.- You must configure a custom schema for LLR using a fully qualified LLR table name. All LLR connections will then use the named schema rather than the default schema when accessing the LLR transaction table.  - Use database specific administration tools to grant permission to access the named LLR table to all users that could access this table via a global transaction. By default, the LLR table is created during boot by the user configured for the connection in the data source. In most cases, the database will only allow access to this user and not allow access to mapped users. Connections within Transactions Now that we have covered the behavior of all of these various options, it’s time to discuss the exception to all of the rules.  When you get a connection within a transaction, it is associated with the transaction context on a particular WLS instance. When getting a connection with a data source configured with non-XA LLR or 1PC (using the JTS driver) with global transactions, the first connection obtained within the transaction is returned on subsequent connection requests regardless of the values of username/password specified and independent of the associated proxy user session, if any. The connection must be shared among all users of the connection when using LLR or 1PC. For XA data sources, the first connection obtained within the global transaction is returned on subsequent connection requests within the application server, regardless of the values of username/password specified and independent of the associated proxy user session, if any.  The connection must be shared among all users of the connection within a global transaction within the application server/JVM.

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  • Constrained A* problem

    - by Ragekit
    I've got a little problem with an A* algorithm that I need to Constrained a little bit. Basically : I use an A* to find the shortest path between 2 randomly placed room in 3D space, and then build a corridor between them. The problem I found is that sometimes it makes chimney like corridors that are not ideal, so I constrict the A* so that if the last movement was up or down, you go sideways. Everything is fine, but in some corner cases, it fails to find a path (when there is obviously one). Like here between the blue and red dot : (i'm in unity btw, but i don't think it matters) Here is the code of the actual A* (a bit long, and some redundency) while(current != goal) { //add stair up / stair down foreach(Node<GridUnit> test in current.Neighbors) { if(!test.Data.empty && test != goal) continue; //bug at arrival; if(test == goal && penul !=null) { Vector3 currentDiff = current.Data.bounds.center - test.Data.bounds.center; if(!Mathf.Approximately(currentDiff.y,0)) { //wanna drop on the last if(!coplanar(test.Data.bounds.center,current.Data.bounds.center,current.Data.parentUnit.bounds.center,to.Data.bounds.center)) { continue; } else { if(Mathf.Approximately(to.Data.bounds.center.x, current.Data.parentUnit.bounds.center.x) && Mathf.Approximately(to.Data.bounds.center.z, current.Data.parentUnit.bounds.center.z)) { continue; } } } } if(current.Data.parentUnit != null) { Vector3 previousDiff = current.Data.parentUnit.bounds.center - current.Data.bounds.center; Vector3 currentDiff = current.Data.bounds.center - test.Data.bounds.center; if(!Mathf.Approximately(previousDiff.y,0)) { if(!Mathf.Approximately(currentDiff.y,0)) { //you wanna drop now : continue; } if(current.Data.parentUnit.parentUnit != null) { if(!coplanar(test.Data.bounds.center,current.Data.bounds.center,current.Data.parentUnit.bounds.center,current.Data.parentUnit.parentUnit.bounds.center)) { continue; }else { if(Mathf.Approximately(test.Data.bounds.center.x, current.Data.parentUnit.parentUnit.bounds.center.x) && Mathf.Approximately(test.Data.bounds.center.z, current.Data.parentUnit.parentUnit.bounds.center.z)) { continue; } } } } } g = current.Data.g + HEURISTIC(current.Data,test.Data); h = HEURISTIC(test.Data,goal.Data); f = g + h; if(open.Contains(test) || closed.Contains(test)) { if(test.Data.f > f) { //found a shorter path going passing through that point test.Data.f = f; test.Data.g = g; test.Data.h = h; test.Data.parentUnit = current.Data; } } else { //jamais rencontré test.Data.f = f; test.Data.h = h; test.Data.g = g; test.Data.parentUnit = current.Data; open.Add(test); } } closed.Add (current); if(open.Count == 0) { Debug.Log("nothingfound"); //nothing more to test no path found, stay to from; List<GridUnit> r = new List<GridUnit>(); r.Add(from.Data); return r; } //sort open from small to biggest travel cost open.Sort(delegate(Node<GridUnit> x, Node<GridUnit> y) { return (int)(x.Data.f-y.Data.f); }); //get the smallest travel cost node; Node<GridUnit> smallest = open[0]; current = smallest; open.RemoveAt(0); } //build the path going backward; List<GridUnit> ret = new List<GridUnit>(); if(penul != null) { ret.Insert(0,to.Data); } GridUnit cur = goal.Data; ret.Insert(0,cur); do{ cur = cur.parentUnit; ret.Insert(0,cur); } while(cur != from.Data); return ret; You see at the start of the foreach i constrict the A* like i said. If you have any insight it would be cool. Thanks

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  • How do I stop and repair a RAID 5 array that has failed and has I/O pending?

    - by Ben Hymers
    The short version: I have a failed RAID 5 array which has a bunch of processes hung waiting on I/O operations on it; how can I recover from this? The long version: Yesterday I noticed Samba access was being very sporadic; accessing the server's shares from Windows would randomly lock up explorer completely after clicking on one or two directories. I assumed it was Windows being a pain and left it. Today the problem is the same, so I did a little digging; the first thing I noticed was that running ps aux | grep smbd gives a lot of lines like this: ben 969 0.0 0.2 96088 4128 ? D 18:21 0:00 smbd -F root 1708 0.0 0.2 93468 4748 ? Ss 18:44 0:00 smbd -F root 1711 0.0 0.0 93468 1364 ? S 18:44 0:00 smbd -F ben 3148 0.0 0.2 96052 4160 ? D Mar07 0:00 smbd -F ... There are a lot of processes stuck in the "D" state. Running ps aux | grep " D" shows up some other processes including my nightly backup script, all of which need to access the volume mounted on my RAID array at some point. After some googling, I found that it might be down to the RAID array failing, so I checked /proc/mdstat, which shows this: ben@jack:~$ cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active raid5 sdb1[3](F) sdc1[1] sdd1[2] 2930271872 blocks level 5, 64k chunk, algorithm 2 [3/2] [_UU] unused devices: <none> And running mdadm --detail /dev/md0 gives this: ben@jack:~$ sudo mdadm --detail /dev/md0 /dev/md0: Version : 00.90 Creation Time : Sat Oct 31 20:53:10 2009 Raid Level : raid5 Array Size : 2930271872 (2794.53 GiB 3000.60 GB) Used Dev Size : 1465135936 (1397.26 GiB 1500.30 GB) Raid Devices : 3 Total Devices : 3 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Mon Mar 7 03:06:35 2011 State : active, degraded Active Devices : 2 Working Devices : 2 Failed Devices : 1 Spare Devices : 0 Layout : left-symmetric Chunk Size : 64K UUID : f114711a:c770de54:c8276759:b34deaa0 Events : 0.208245 Number Major Minor RaidDevice State 3 8 17 0 faulty spare rebuilding /dev/sdb1 1 8 33 1 active sync /dev/sdc1 2 8 49 2 active sync /dev/sdd1 I believe this says that sdb1 has failed, and so the array is running with two drives out of three 'up'. Some advice I found said to check /var/log/messages for notices of failures, and sure enough there are plenty: ben@jack:~$ grep sdb /var/log/messages ... Mar 7 03:06:35 jack kernel: [4525155.384937] md/raid:md0: read error NOT corrected!! (sector 400644912 on sdb1). Mar 7 03:06:35 jack kernel: [4525155.389686] md/raid:md0: read error not correctable (sector 400644920 on sdb1). Mar 7 03:06:35 jack kernel: [4525155.389686] md/raid:md0: read error not correctable (sector 400644928 on sdb1). Mar 7 03:06:35 jack kernel: [4525155.389688] md/raid:md0: read error not correctable (sector 400644936 on sdb1). Mar 7 03:06:56 jack kernel: [4525176.231603] sd 0:0:1:0: [sdb] Unhandled sense code Mar 7 03:06:56 jack kernel: [4525176.231605] sd 0:0:1:0: [sdb] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE Mar 7 03:06:56 jack kernel: [4525176.231608] sd 0:0:1:0: [sdb] Sense Key : Medium Error [current] [descriptor] Mar 7 03:06:56 jack kernel: [4525176.231623] sd 0:0:1:0: [sdb] Add. Sense: Unrecovered read error - auto reallocate failed Mar 7 03:06:56 jack kernel: [4525176.231627] sd 0:0:1:0: [sdb] CDB: Read(10): 28 00 17 e1 5f bf 00 01 00 00 To me it is clear that device sdb has failed, and I need to stop the array, shutdown, replace it, reboot, then repair the array, bring it back up and mount the filesystem. I cannot hot-swap a replacement drive in, and don't want to leave the array running in a degraded state. I believe I am supposed to unmount the filesystem before stopping the array, but that is failing, and that is where I'm stuck now: ben@jack:~$ sudo umount /storage umount: /storage: device is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1)) It is indeed busy; there are some 30 or 40 processes waiting on I/O. What should I do? Should I kill all these processes and try again? Is that a wise move when they are 'uninterruptable'? What would happen if I tried to reboot? Please let me know what you think I should do. And please ask if you need any extra information to diagnose the problem or to help!

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  • Xen kernel can't see 2 disks of 6 of 1TB, does it have a limitation?

    - by PartySoft
    Linux gentoo-xen 2.6.18-xen-r12 #3 SMP Tue Oct 5 09:28:53 PDT 2010 x86_64 Intel(R) Xeon(R) CPU E5506 @ 2.13GHz GenuineIntel GNU/Linux I have 6 disks of 1 TB and i can't see all of them only 4, can anyone give me an ideea what can i do ? Filesystem Size Used Avail Use% Mounted on rootfs 886G 4.4G 836G 1% / /dev/sda3 886G 4.4G 836G 1% / rc-svcdir 1.0M 44K 980K 5% /lib64/rc/init.d shm 7.9G 0 7.9G 0% /dev/shm /dev/sdb1 917G 200M 871G 1% /home2 /dev/sdc1 917G 200M 871G 1% /home3 /dev/sdd1 917G 200M 871G 1% /home4 The hardware is Dual xeon E5506 processors on a supermicro X8DTL mobo 4.346585] ata3.00: ATA-8, max UDMA/133, 1953525168 sectors: LBA48 NCQ (depth 0/32) [ 4.346588] ata3.00: ata3: dev 0 multi count 16 [ 4.352861] ata3.00: configured for UDMA/133 [ 4.352867] scsi3 : ata_piix [ 4.352875] PM: Adding info for No Bus:host3 [ 4.510584] ata4.00: ATA-8, max UDMA/133, 1953525168 sectors: LBA48 NCQ (depth 0/32) [ 4.510587] ata4.00: ata4: dev 0 multi count 16 [ 4.516848] ata4.00: configured for UDMA/133 [ 4.516861] PM: Adding info for No Bus:target2:0:0 [ 4.516905] Vendor: ATA Model: SAMSUNG HD103SJ Rev: 1AJ1 [ 4.516910] Type: Direct-Access ANSI SCSI revision: 05 [ 4.516920] PM: Adding info for scsi:2:0:0:0 [ 4.517452] SCSI device sde: 1953525168 512-byte hdwr sectors (1000205 MB) [ 4.517460] sde: Write Protect is off [ 4.517461] sde: Mode Sense: 00 3a 00 00 [ 4.517478] SCSI device sde: drive cache: write back [ 4.517514] SCSI device sde: 1953525168 512-byte hdwr sectors (1000205 MB) [ 4.517521] sde: Write Protect is off [ 4.517522] sde: Mode Sense: 00 3a 00 00 [ 4.517532] SCSI device sde: drive cache: write back [ 4.517534] sde: sde1 [ 4.524551] sd 2:0:0:0: Attached scsi disk sde [ 4.524855] sd 2:0:0:0: Attached scsi generic sg4 type 0 [ 4.524874] PM: Adding info for No Bus:target3:0:0 [ 4.524928] Vendor: ATA Model: SAMSUNG HD103SJ Rev: 1AJ1 [ 4.524933] Type: Direct-Access ANSI SCSI revision: 05 [ 4.524946] PM: Adding info for scsi:3:0:0:0 [ 4.525216] SCSI device sdf: 1953525168 512-byte hdwr sectors (1000205 MB) [ 4.525227] sdf: Write Protect is off [ 4.525228] sdf: Mode Sense: 00 3a 00 00 [ 4.525242] SCSI device sdf: drive cache: write back [ 4.525280] SCSI device sdf: 1953525168 512-byte hdwr sectors (1000205 MB) [ 4.525286] sdf: Write Protect is off [ 4.525289] sdf: Mode Sense: 00 3a 00 00 [ 4.525301] SCSI device sdf: drive cache: write back [ 4.525302] sdf: sdf1 [ 4.532691] sd 3:0:0:0: Attached scsi disk sdf [ 4.533010] sd 3:0:0:0: Attached scsi generic sg5 type 0 [ 4.977669] scsi: <fdomain> Detection failed (no card) [ 5.030479] GDT-HA: Storage RAID Controller Driver. Version: 3.05 [ 5.030635] GDT-HA: Found 0 PCI Storage RAID Controllers [ 5.372350] Fusion MPT base driver 3.04.01 [ 5.372358] Copyright (c) 1999-2005 LSI Logic Corporation [ 5.579176] Fusion MPT SPI Host driver 3.04.01 [ 5.881777] ieee1394: Initialized config rom entry `ip1394' [ 6.166745] ieee1394: sbp2: Driver forced to serialize I/O (serialize_io=1) [ 6.166748] ieee1394: sbp2: Try serialize_io=0 for better performance [ 6.428866] md: md driver 0.90.3 MAX_MD_DEVS=256, MD_SB_DISKS=27 [ 6.428872] md: bitmap version 4.39 [ 6.431518] md: raid0 personality registered for level 0 [ 6.495979] md: raid1 personality registered for level 1 [ 6.570270] raid5: automatically using best checksumming function: generic_sse [ 6.575523] generic_sse: 6608.000 MB/sec [ 6.575526] raid5: using function: generic_sse (6608.000 MB/sec) [ 6.596226] raid6: int64x1 1835 MB/s [ 6.613231] raid6: int64x2 1773 MB/s [ 6.630256] raid6: int64x4 1675 MB/s [ 6.647296] raid6: int64x8 1027 MB/s [ 6.664267] raid6: sse2x1 3578 MB/s [ 6.681268] raid6: sse2x2 4207 MB/s [ 6.698280] raid6: sse2x4 4625 MB/s [ 6.698281] raid6: using algorithm sse2x4 (4625 MB/s) [ 6.698285] md: raid6 personality registered for level 6 [ 6.698286] md: raid5 personality registered for level 5 [ 6.698288] md: raid4 personality registered for level 4 [ 6.781090] md: raid10 personality registered for level 10 [ 7.007043] Intel(R) PRO/1000 Network Driver - version 7.1.9-k4 [ 7.007046] Copyright (c) 1999-2006 Intel Corporation. [ 9.229465] kjournald starting. Commit interval 5 seconds [ 9.229476] EXT3-fs: mounted filesystem with ordered data mode.

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  • Openswan ipsec transport tunnel not going up

    - by gparent
    On ClusterA and B I have installed the "openswan" package on Debian Squeeze. ClusterA ip is 172.16.0.107, B is 172.16.0.108 When they ping one another, it does not reach the destination. /etc/ipsec.conf: version 2.0 # conforms to second version of ipsec.conf specification config setup protostack=netkey oe=off conn L2TP-PSK-CLUSTER type=transport left=172.16.0.107 right=172.16.0.108 auto=start ike=aes128-sha1-modp2048 authby=secret compress=yes /etc/ipsec.secrets: 172.16.0.107 172.16.0.108 : PSK "L2TPKEY" 172.16.0.108 172.16.0.107 : PSK "L2TPKEY" Here is the result of ipsec verify on both machines: root@cluster2:~# ipsec verify Checking your system to see if IPsec got installed and started correctly: Version check and ipsec on-path [OK] Linux Openswan U2.6.28/K2.6.32-5-amd64 (netkey) Checking for IPsec support in kernel [OK] NETKEY detected, testing for disabled ICMP send_redirects [OK] NETKEY detected, testing for disabled ICMP accept_redirects [OK] Checking that pluto is running [OK] Pluto listening for IKE on udp 500 [OK] Pluto listening for NAT-T on udp 4500 [FAILED] Checking for 'ip' command [OK] Checking for 'iptables' command [OK] Opportunistic Encryption Support [DISABLED] root@cluster2:~# This is the end of the output of ipsec auto --status: 000 "cluster": 172.16.0.108<172.16.0.108>[+S=C]...172.16.0.107<172.16.0.107>[+S=C]; prospective erouted; eroute owner: #0 000 "cluster": myip=unset; hisip=unset; 000 "cluster": ike_life: 3600s; ipsec_life: 28800s; rekey_margin: 540s; rekey_fuzz: 100%; keyingtries: 0 000 "cluster": policy: PSK+ENCRYPT+COMPRESS+PFS+UP+IKEv2ALLOW+lKOD+rKOD; prio: 32,32; interface: eth0; 000 "cluster": newest ISAKMP SA: #1; newest IPsec SA: #0; 000 "cluster": IKE algorithm newest: AES_CBC_128-SHA1-MODP2048 000 000 #3: "cluster":500 STATE_QUICK_R0 (expecting QI1); EVENT_CRYPTO_FAILED in 298s; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate 000 #2: "cluster":500 STATE_QUICK_I1 (sent QI1, expecting QR1); EVENT_RETRANSMIT in 13s; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate 000 #1: "cluster":500 STATE_MAIN_I4 (ISAKMP SA established); EVENT_SA_REPLACE in 2991s; newest ISAKMP; lastdpd=-1s(seq in:0 out:0); idle; import:admin initiate 000 Interestingly enough, if I do ike-scan on the server here's what happens: Doesn't seem to take my ike settings into account root@cluster1:~# ike-scan -M 172.16.0.108 Starting ike-scan 1.9 with 1 hosts (http://www.nta-monitor.com/tools/ike-scan/) 172.16.0.108 Main Mode Handshake returned HDR=(CKY-R=641bffa66ba717b6) SA=(Enc=3DES Hash=SHA1 Auth=PSK Group=2:modp1024 LifeType=Seconds LifeDuration(4)=0x00007080) VID=4f45517b4f7f6e657a7b4351 VID=afcad71368a1f1c96b8696fc77570100 (Dead Peer Detection v1.0) Ending ike-scan 1.9: 1 hosts scanned in 0.008 seconds (118.19 hosts/sec). 1 returned handshake; 0 returned notify root@cluster1:~# I can't tell what's going on here, this is pretty much the simplest config I can have according to the examples.

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  • Site-to-site VPN using MD5 instead of SHA and getting regular disconnection

    - by Steven
    We are experiencing some strange behavior with a site-to-site IPsec VPN that goes down about every week for 30 minutes (Iam told 30 minutes exactly). I don't have access to the logs, so it's difficult to troubleshoot. What is also strange is that the two VPN devices are set to use SHA hash algorithm but apparently end up agreeing to use MD5. Does anybody have a clue? or is this just insufficient information? Edit: Here is an extract of the log of one of the two VPN devices, which is a Cisco 3000 series VPN concentrator. 27981 03/08/2010 10:02:16.290 SEV=4 IKE/41 RPT=16120 xxxxxxxx IKE Initiator: New Phase 1, Intf 2, IKE Peer xxxxxxxx local Proxy Address xxxxxxxx, remote Proxy Address xxxxxxxx, SA (L2L: 1A) 27983 03/08/2010 10:02:56.930 SEV=4 IKE/41 RPT=16121 xxxxxxxx IKE Initiator: New Phase 1, Intf 2, IKE Peer xxxxxxxx local Proxy Address xxxxxxxx, remote Proxy Address xxxxxxxx, SA (L2L: 1A) 27986 03/08/2010 10:03:35.370 SEV=4 IKE/41 RPT=16122 xxxxxxxx IKE Initiator: New Phase 1, Intf 2, IKE Peer xxxxxxxx local Proxy Address xxxxxxxx, remote Proxy Address xxxxxxxx, SA (L2L: 1A) [… same continues for another 15 minutes …] 28093 03/08/2010 10:19:46.710 SEV=4 IKE/41 RPT=16140 xxxxxxxx IKE Initiator: New Phase 1, Intf 2, IKE Peer xxxxxxxx local Proxy Address xxxxxxxx, remote Proxy Address xxxxxxxx, SA (L2L: 1A) 28096 03/08/2010 10:20:17.720 SEV=5 IKE/172 RPT=1291 xxxxxxxx Group [xxxxxxxx] Automatic NAT Detection Status: Remote end is NOT behind a NAT device This end IS behind a NAT device 28100 03/08/2010 10:20:17.820 SEV=3 IKE/134 RPT=79 xxxxxxxx Group [xxxxxxxx] Mismatch: Configured LAN-to-LAN proposal differs from negotiated proposal. Verify local and remote LAN-to-LAN connection lists. 28103 03/08/2010 10:20:17.820 SEV=4 IKE/119 RPT=1197 xxxxxxxx Group [xxxxxxxx] PHASE 1 COMPLETED 28104 03/08/2010 10:20:17.820 SEV=4 AUTH/22 RPT=1031 xxxxxxxx User [xxxxxxxx] Group [xxxxxxxx] connected, Session Type: IPSec/LAN- to-LAN 28106 03/08/2010 10:20:17.820 SEV=4 AUTH/84 RPT=39 LAN-to-LAN tunnel to headend device xxxxxxxx connected 28110 03/08/2010 10:20:17.920 SEV=5 IKE/25 RPT=1291 xxxxxxxx Group [xxxxxxxx] Received remote Proxy Host data in ID Payload: Address xxxxxxxx, Protocol 0, Port 0 28113 03/08/2010 10:20:17.920 SEV=5 IKE/24 RPT=88 xxxxxxxx Group [xxxxxxxx] Received local Proxy Host data in ID Payload: Address xxxxxxxx, Protocol 0, Port 0 28116 03/08/2010 10:20:17.920 SEV=5 IKE/66 RPT=1290 xxxxxxxx Group [xxxxxxxx] IKE Remote Peer configured for SA: L2L: 1A 28117 03/08/2010 10:20:17.930 SEV=5 IKE/25 RPT=1292 xxxxxxxx Group [xxxxxxxx] Received remote Proxy Host data in ID Payload: Address xxxxxxxx, Protocol 0, Port 0 28120 03/08/2010 10:20:17.930 SEV=5 IKE/24 RPT=89 xxxxxxxx Group [xxxxxxxx] Received local Proxy Host data in ID Payload: Address xxxxxxxx, Protocol 0, Port 0 28123 03/08/2010 10:20:17.930 SEV=5 IKE/66 RPT=1291 xxxxxxxx Group [xxxxxxxx] IKE Remote Peer configured for SA: L2L: 1A 28124 03/08/2010 10:20:18.070 SEV=4 IKE/173 RPT=17330 xxxxxxxx Group [xxxxxxxx] NAT-Traversal successfully negotiated! IPSec traffic will be encapsulated to pass through NAT devices. 28127 03/08/2010 10:20:18.070 SEV=4 IKE/49 RPT=17332 xxxxxxxx Group [xxxxxxxx] Security negotiation complete for LAN-to-LAN Group (xxxxxxxx) Responder, Inbound SPI = 0x56a4fe5c, Outbound SPI = 0xcdfc3892 28130 03/08/2010 10:20:18.070 SEV=4 IKE/120 RPT=17332 xxxxxxxx Group [xxxxxxxx] PHASE 2 COMPLETED (msgid=37b3b298) 28131 03/08/2010 10:20:18.750 SEV=4 IKE/41 RPT=16141 xxxxxxxx Group [xxxxxxxx] IKE Initiator: New Phase 2, Intf 2, IKE Peer xxxxxxxx local Proxy Address xxxxxxxx, remote Proxy Address xxxxxxxx, SA (L2L: 1A) 28135 03/08/2010 10:20:18.870 SEV=4 IKE/173 RPT=17331 xxxxxxxx Group [xxxxxxxx] NAT-Traversal successfully negotiated! IPSec traffic will be encapsulated to pass through NAT devices.

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  • Linux software RAID6: rebuild slow

    - by Ole Tange
    I am trying to find the bottleneck in the rebuilding of a software raid6. ## Pause rebuilding when measuring raw I/O performance # echo 1 > /proc/sys/dev/raid/speed_limit_min # echo 1 > /proc/sys/dev/raid/speed_limit_max ## Drop caches so that does not interfere with measuring # sync ; echo 3 | tee /proc/sys/vm/drop_caches >/dev/null # time parallel -j0 "dd if=/dev/{} bs=256k count=4000 | cat >/dev/null" ::: sdbd sdbc sdbf sdbm sdbl sdbk sdbe sdbj sdbh sdbg 4000+0 records in 4000+0 records out 1048576000 bytes (1.0 GB) copied, 7.30336 s, 144 MB/s [... similar for each disk ...] # time parallel -j0 "dd if=/dev/{} skip=15000000 bs=256k count=4000 | cat >/dev/null" ::: sdbd sdbc sdbf sdbm sdbl sdbk sdbe sdbj sdbh sdbg 4000+0 records in 4000+0 records out 1048576000 bytes (1.0 GB) copied, 12.7991 s, 81.9 MB/s [... similar for each disk ...] So we can read sequentially at 140 MB/s in the outer tracks and 82 MB/s in the inner tracks on all the drives simultaneously. Sequential write performance is similar. This would lead me to expect a rebuild speed of 82 MB/s or more. # echo 800000 > /proc/sys/dev/raid/speed_limit_min # echo 800000 > /proc/sys/dev/raid/speed_limit_max # cat /proc/mdstat md2 : active raid6 sdbd[10](S) sdbc[9] sdbf[0] sdbm[8] sdbl[7] sdbk[6] sdbe[11] sdbj[4] sdbi[3](F) sdbh[2] sdbg[1] 27349121408 blocks super 1.2 level 6, 128k chunk, algorithm 2 [9/8] [UUU_UUUUU] [=========>...........] recovery = 47.3% (1849905884/3907017344) finish=855.9min speed=40054K/sec But we only get 40 MB/s. And often this drops to 30 MB/s. # iostat -dkx 1 sdbc 0.00 8023.00 0.00 329.00 0.00 33408.00 203.09 0.70 2.12 1.06 34.80 sdbd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sdbe 13.00 0.00 8334.00 0.00 33388.00 0.00 8.01 0.65 0.08 0.06 47.20 sdbf 0.00 0.00 8348.00 0.00 33388.00 0.00 8.00 0.58 0.07 0.06 48.00 sdbg 16.00 0.00 8331.00 0.00 33388.00 0.00 8.02 0.71 0.09 0.06 48.80 sdbh 961.00 0.00 8314.00 0.00 37100.00 0.00 8.92 0.93 0.11 0.07 54.80 sdbj 70.00 0.00 8276.00 0.00 33384.00 0.00 8.07 0.78 0.10 0.06 48.40 sdbk 124.00 0.00 8221.00 0.00 33380.00 0.00 8.12 0.88 0.11 0.06 47.20 sdbl 83.00 0.00 8262.00 0.00 33380.00 0.00 8.08 0.96 0.12 0.06 47.60 sdbm 0.00 0.00 8344.00 0.00 33376.00 0.00 8.00 0.56 0.07 0.06 47.60 iostat says the disks are not 100% busy (but only 40-50%). This fits with the hypothesis that the max is around 80 MB/s. Since this is software raid the limiting factor could be CPU. top says: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 38520 root 20 0 0 0 0 R 64 0.0 2947:50 md2_raid6 6117 root 20 0 0 0 0 D 53 0.0 473:25.96 md2_resync So md2_raid6 and md2_resync are clearly busy taking up 64% and 53% of a CPU respectively, but not near 100%. The chunk size (128k) of the RAID was chosen after measuring which chunksize gave the least CPU penalty. If this speed is normal: What is the limiting factor? Can I measure that? If this speed is not normal: How can I find the limiting factor? Can I change that?

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  • e2fsck / resize2fs problems

    - by BlakBat
    I've got 6 drives (each 1.5T, all same model and firmware revision) that are part of a RAID5 array. The RAID5 makes a LVM volume group and a logical group. The latter contains only one ext3 partition. I've recently ran: e2fsck -f /dev/vg03/lv01 && resize2fs -M /dev/vg03/lv01 which exited without an error. Now when I try to mount /dev/vg03/lv01 I get: EXT3-fs error (device dm-0): ext3_check_descriptors: Block bitmap for group 30533 not in group (block 1000532368)! EXT3-fs: group descriptors corrupted! How do I get out of this predicament? This is all the info I can currently give you: fdisk -l /dev/sd[cdefgh] shows (correctly) that they are "Linux raid autodetect" but fdisk now shows: fdisk -l /dev/md0 Disk /dev/md0: 7501.5 GB, 7501495664640 bytes ... Disk identifier: 0x00000000 Disk /dev/md0 doesn't contain a valid partition table (instead of a LVM type partition) fdisk -l /dev/vg03/lv01 Disk /dev/vg03/lv01: 7501.5 GB, 7501491732480 bytes ... Disk identifier: 0x00000000 Disk /dev/vg03/lv01 doesn't contain a valid partition table (instead of a ext3 type partition) I've tried: e2fsck -fy /dev/vg03/lv01 e2fsck 1.41.12 (17-May-2010) e2fsck: Group descriptors look bad... trying backup blocks... Block bitmap for group 30533 is not in group. (block 1000532368) Relocate? yes Inode bitmap for group 30533 is not in group. (block 1000532369) Relocate? yes Pass 1: Checking inodes, blocks, and sizes Relocating group 30533's block bitmap to 1000524246... Error allocating 1 contiguous block(s) in block group 30533 for inode bitmap: Could not allocate block in ext2 filesystem e2fsck: aborted Extra information I can give you: cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active (auto-read-only) raid5 sdg1[0] sdh1[5] sdf1[4] sde1[3] sdc1[2] sdd1[1] 7325679360 blocks level 5, 128k chunk, algorithm 2 [6/6] [UUUUUU] bitmap: 1/175 pages [4KB], 4096KB chunk unused devices: Lastly, all smartctl tests (short and extendend) showed no errors on any of the disks. Should I try to resize2fs to grow /dev/vg03/lv01 and redo a e2fsck ? Should I cfdisk /dev/md0 and /dev/vg03/lv01 back to their real types? Thanks in advance for all and any help. 2011-09-20 UPDATE I issued the following commands and was able to remount the partition, but by viewing the size (df) of before and after, it seems that 1Tb of data have gone missing. By checking the MD5SUMS (from an old backup) of some files with the "same" files from the remounted partition, some errors have been detected. Commands issued to remount the partition were: dumpe2fs /dev/vg03/lv01 Block count: 1000491435<br /> Block size: 4096<br /> tune2fs -O ^has_journal /dev/vg03/lv01 resize2fs -p /dev/vg03/lv01 dumpe2fs /dev/vg03/lv01 Block count: 1831418880<br /> Block size: 4096<br /> mount -o ro,noatime /dev/vg03/lv01 /mnt/raid OK... but files have been damaged / gone missing.

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  • Windows 7 inbuilt and 3rd party (de)fragmentation related queries

    - by Karan
    I have a pretty good idea of how files end up getting fragmented. That said, I just copied ~3,200 files of varying sizes (from a few KB to ~20GB) from an external USB HDD to an internal, freshly formatted (under Windows 7 x64), NTFS, 2TB, 5400RPM, WD, SATA, non-system (i.e. secondary) drive, filling it up 57%. Since it should have been very much possible for each file to have been stored in one contiguous block, I expected the drive to be fragmented not more than 1-2% at most after this rather lengthy exercise (unfortunately this older machine doesn't support USB 3.0). Windows 7's inbuilt defrag utility told me after a quick analysis that the drive was fragmented only 1% or so, which dovetailed neatly with my expectations. However, just out of curiosity I downloaded and ran the latest portable x64 version of Piriform's Defraggler, and was shocked to see the drive being reported as being ~85% fragmented! The portable version of Auslogics Disk Defrag also agreed with Defraggler, and both clearly expected to grind away for ~10 hours to completely defragment the drive. 1) How in blazes could the inbuilt and 3rd party defrag utils disagree so badly? I mean, 10-20% variance is probably understandable, but 1% and 85% are miles apart! This Engineering Windows 7 blog post states: In Windows XP, any file that is split into more than one piece is considered fragmented. Not so in Windows Vista if the fragments are large enough – the defragmentation algorithm was changed (from Windows XP) to ignore pieces of a file that are larger than 64MB. As a result, defrag in XP and defrag in Vista will report different amounts of fragmentation on a volume. ... [Please read the entire post so the quote is not taken out of context.] Could it simply be that the 3rd party defrag utils ignore this post-XP change and continue to use analysis algos similar to those XP used? 2) Assuming that the 3rd party utils aren't lying about the real extent of fragmentation (which Windows is downplaying post-XP), how could the files have even got fragmented so badly given they were just copied over afresh to an empty drive? 3) If vastly differing analysis algos explain the yawning gap, which do I believe? I'm no defrag fanatic for sure, but 85% is enough to make me seriously consider spending 10 hours defragging this drive. On the other hand, 1% reported by Windows' own defragger clearly implies that there is no cause for concern and defragging would actually have negative consequences (as per the post). Is Windows' assumption valid and should I just let it be, or will there be any noticeable performance gains after running one of the 3rd party utils for 10 hours straight? 4) I see that out of the box Windows 7 defrag is scheduled to run weekly. Does anyone know whether it defrags every single time, or only if its analysis reveals a fragmentation percentage over a set threshold? If the latter, what is this threshold and can it be changed, maybe via a Registry edit? Thanks for reading through (my first query on this wonderful site!) and for any helpful replies. Also, if you're answering question #3, please keep in mind that any speed increases post defragging with 3rd party utils vis-à-vis Windows' inbuilt program should not include pre-Vista (preferably pre-Win7) examples. Further, examples of programs that made your system boot faster won't help in this case, since this is a non-system drive (although one that'll still be used daily).

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  • Reconstructing the disk order in RAID 6 with 7 disks

    - by rkotulla
    a little background to this question first: I am running a RAID-6 within a QNAP TS869L external RAID/NAS system. I started with 5 disks of 3 TB each back in the day, and later added another 2 disks of 3TB to the RAID. The QNAP internals handled the growing and re-syncing etc, and everything seemd to be perfectly fine. About 2 weeks ago, I had one of the disks (disk #5, disk #2 has gone bad in the mean time) fail, and somehow (I have no idea why), also disks 1 and 2 got kicked out of the array. I replaced disk #5, but the RAID didn't start working again. After some calls to QNAP technical support, they re-created the array (using mdadm --create --force --assume-clean ...), but the resulting array couldn't find a filesystem, and I was kindly referred to contact a data recovery company that I can't afford. After some digging through old log files, resetting the disk to factory default, etc, I found a few errors that were made during this re-create - I wish I still had some of the original metadata, but unfortunately i don't (I definitely learned that lesson). I'm currently at the point where I know the correct chunk-size (64K), metadata-version (1.0; factory default was 0.9, but from what I read 0.9 doesn't handle disks over 2 TB, mine are 3 TB), and I now find the ext4 filesystem that should be on the disks. Only variable left to determine is the right disk order! I started using the description found in answer #4 of "Recover RAID 5 data after created new array instead of re-using" but am a little confused on what the order should be for a proper RAID-6. RAID-5 is pretty well documented in a number of places, but RAID-6 much less so. Also, does the layout, i.e. distribution of parity and data chunks across the disks, change after the growing of the array from 5 to 7 disks, or does the re-sync re-organize them in such a way a native 7-disk RAID-6 would have been? Thanks some more mdadm output that might be helpful: mdadm version: [~] # mdadm --version mdadm - v2.6.3 - 20th August 2007 mdadm details from one of the disks in the array: [~] # mdadm --examine /dev/sda3 /dev/sda3: Magic : a92b4efc Version : 1.0 Feature Map : 0x0 Array UUID : 1c1614a5:e3be2fbb:4af01271:947fe3aa Name : 0 Creation Time : Tue Jun 10 10:27:58 2014 Raid Level : raid6 Raid Devices : 7 Used Dev Size : 5857395112 (2793.02 GiB 2998.99 GB) Array Size : 29286975360 (13965.12 GiB 14994.93 GB) Used Size : 5857395072 (2793.02 GiB 2998.99 GB) Super Offset : 5857395368 sectors State : clean Device UUID : 7c572d8f:20c12727:7e88c888:c2c357af Update Time : Tue Jun 10 13:01:06 2014 Checksum : d275c82d - correct Events : 7036 Chunk Size : 64K Array Slot : 0 (0, 1, failed, 3, failed, 5, 6) Array State : Uu_u_uu 2 failed mdadm details for the array in the current disk-order (based on my best guess reconstructed from old log-files) [~] # mdadm --detail /dev/md0 /dev/md0: Version : 01.00.03 Creation Time : Tue Jun 10 10:27:58 2014 Raid Level : raid6 Array Size : 14643487680 (13965.12 GiB 14994.93 GB) Used Dev Size : 2928697536 (2793.02 GiB 2998.99 GB) Raid Devices : 7 Total Devices : 5 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Tue Jun 10 13:01:06 2014 State : clean, degraded Active Devices : 5 Working Devices : 5 Failed Devices : 0 Spare Devices : 0 Chunk Size : 64K Name : 0 UUID : 1c1614a5:e3be2fbb:4af01271:947fe3aa Events : 7036 Number Major Minor RaidDevice State 0 8 3 0 active sync /dev/sda3 1 8 19 1 active sync /dev/sdb3 2 0 0 2 removed 3 8 51 3 active sync /dev/sdd3 4 0 0 4 removed 5 8 99 5 active sync /dev/sdg3 6 8 83 6 active sync /dev/sdf3 output from /proc/mdstat (md8, md9, and md13 are internally used RAIDs holding swap, etc; the one I'm after is md0) [~] # more /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath] md0 : active raid6 sdf3[6] sdg3[5] sdd3[3] sdb3[1] sda3[0] 14643487680 blocks super 1.0 level 6, 64k chunk, algorithm 2 [7/5] [UU_U_UU] md8 : active raid1 sdg2[2](S) sdf2[3](S) sdd2[4](S) sdc2[5](S) sdb2[6](S) sda2[1] sde2[0] 530048 blocks [2/2] [UU] md13 : active raid1 sdg4[3] sdf4[4] sde4[5] sdd4[6] sdc4[2] sdb4[1] sda4[0] 458880 blocks [8/7] [UUUUUUU_] bitmap: 21/57 pages [84KB], 4KB chunk md9 : active raid1 sdg1[6] sdf1[5] sde1[4] sdd1[3] sdc1[2] sda1[0] sdb1[1] 530048 blocks [8/7] [UUUUUUU_] bitmap: 37/65 pages [148KB], 4KB chunk unused devices: <none>

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  • duplicate cache pages: Varnish

    - by Sukhjinder Singh
    Recently we have configured Varnish on our server, it was successfully setup but we noticed that if we open any page in multiple browsers, the Varnish send request to Apache not matter page is cached or not. If we refresh twice on each browser it creates duplicate copies of the same page. What exactly should happen: If any page is cached by Varnish, the subsequent request should be served from Varnish itself when we are opening the same page in browser OR we are opening that page from different IP address. Following is my default.vcl file backend default { .host = "127.0.0.1"; .port = "80"; } sub vcl_recv { if( req.url ~ "^/search/.*$") { }else { set req.url = regsub(req.url, "\?.*", ""); } if (req.restarts == 0) { if (req.http.x-forwarded-for) { set req.http.X-Forwarded-For = req.http.X-Forwarded-For + ", " + client.ip; } else { set req.http.X-Forwarded-For = client.ip; } } if (!req.backend.healthy) { unset req.http.Cookie; } set req.grace = 6h; if (req.url ~ "^/status\.php$" || req.url ~ "^/update\.php$" || req.url ~ "^/admin$" || req.url ~ "^/admin/.*$" || req.url ~ "^/flag/.*$" || req.url ~ "^.*/ajax/.*$" || req.url ~ "^.*/ahah/.*$") { return (pass); } if (req.url ~ "(?i)\.(pdf|asc|dat|txt|doc|xls|ppt|tgz|csv|png|gif|jpeg|jpg|ico|swf|css|js)(\?.*)?$") { unset req.http.Cookie; } if (req.http.Cookie) { set req.http.Cookie = ";" + req.http.Cookie; set req.http.Cookie = regsuball(req.http.Cookie, "; +", ";"); set req.http.Cookie = regsuball(req.http.Cookie, ";(SESS[a-z0-9]+|SSESS[a-z0-9]+|NO_CACHE)=", "; \1="); set req.http.Cookie = regsuball(req.http.Cookie, ";[^ ][^;]*", ""); set req.http.Cookie = regsuball(req.http.Cookie, "^[; ]+|[; ]+$", ""); if (req.http.Cookie == "") { unset req.http.Cookie; } else { return (pass); } } if (req.request != "GET" && req.request != "HEAD" && req.request != "PUT" && req.request != "POST" && req.request != "TRACE" && req.request != "OPTIONS" && req.request != "DELETE") {return(pipe);} /* Non-RFC2616 or CONNECT which is weird. */ if (req.request != "GET" && req.request != "HEAD") { return (pass); } if (req.http.Accept-Encoding) { if (req.url ~ "\.(jpg|png|gif|gz|tgz|bz2|tbz|mp3|ogg)$") { # No point in compressing these remove req.http.Accept-Encoding; } else if (req.http.Accept-Encoding ~ "gzip") { set req.http.Accept-Encoding = "gzip"; } else if (req.http.Accept-Encoding ~ "deflate") { set req.http.Accept-Encoding = "deflate"; } else { # unknown algorithm remove req.http.Accept-Encoding; } } return (lookup); } sub vcl_deliver { if (obj.hits > 0) { set resp.http.X-Varnish-Cache = "HIT"; } else { set resp.http.X-Varnish-Cache = "MISS"; } } sub vcl_fetch { if (beresp.status == 404 || beresp.status == 301 || beresp.status == 500) { set beresp.ttl = 10m; } if (req.url ~ "(?i)\.(pdf|asc|dat|txt|doc|xls|ppt|tgz|csv|png|gif|jpeg|jpg|ico|swf|css|js)(\?.*)?$") { unset beresp.http.set-cookie; } set beresp.grace = 6h; } sub vcl_hash { hash_data(req.url); if (req.http.host) { hash_data(req.http.host); } else { hash_data(server.ip); } return (hash); } sub vcl_pipe { set req.http.connection = "close"; } sub vcl_hit { if (req.request == "PURGE") {ban_url(req.url); error 200 "Purged";} if (!obj.ttl > 0s) {return(pass);} } sub vcl_miss { if (req.request == "PURGE") {error 200 "Not in cache";} }

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  • SunTlsRsaPremasterSecret KeyGenerator not available

    - by Jill
    Hi, I encountered an error when my application tries to load a RSA Algorithm provider class from JAVA. The exception stack is as follow: javax.jms.JMSException: RSA premaster secret error at org.apache.activemq.util.JMSExceptionSupport.create(JMSExceptionSupport.java:49) at org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1255) at org.apache.activemq.ActiveMQConnection.ensureConnectionInfoSent(ActiveMQConnection.java:1350) at org.apache.activemq.ActiveMQConnection.setClientID(ActiveMQConnection.java:388) at com.trendmicro.tmsm.TMSMAgent.open(TMSMAgent.java:63) Caused by: javax.net.ssl.SSLKeyException: RSA premaster secret error at com.sun.net.ssl.internal.ssl.RSAClientKeyExchange.<init>(RSAClientKeyExchange.java:97) at com.sun.net.ssl.internal.ssl.ClientHandshaker.serverHelloDone(ClientHandshaker.java:634) at com.sun.net.ssl.internal.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:226) at com.sun.net.ssl.internal.ssl.Handshaker.processLoop(Handshaker.java:516) at com.sun.net.ssl.internal.ssl.Handshaker.process_record(Handshaker.java:454) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:884) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1112) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.writeRecord(SSLSocketImpl.java:623) at com.sun.net.ssl.internal.ssl.AppOutputStream.write(AppOutputStream.java:59) at org.apache.activemq.transport.tcp.TcpBufferedOutputStream.flush(TcpBufferedOutputStream.java:115) at java.io.DataOutputStream.flush(DataOutputStream.java:106) at org.apache.activemq.transport.tcp.TcpTransport.oneway(TcpTransport.java:167) at org.apache.activemq.transport.InactivityMonitor.oneway(InactivityMonitor.java:237) at org.apache.activemq.transport.WireFormatNegotiator.sendWireFormat(WireFormatNegotiator.java:168) at org.apache.activemq.transport.WireFormatNegotiator.sendWireFormat(WireFormatNegotiator.java:84) at org.apache.activemq.transport.WireFormatNegotiator.start(WireFormatNegotiator.java:74) at org.apache.activemq.transport.failover.FailoverTransport.doReconnect(FailoverTransport.java:715) at org.apache.activemq.transport.failover.FailoverTransport$2.iterate(FailoverTransport.java:115) at org.apache.activemq.thread.PooledTaskRunner.runTask(PooledTaskRunner.java:122) at org.apache.activemq.thread.PooledTaskRunner$1.run(PooledTaskRunner.java:43) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:637) Caused by: java.security.NoSuchAlgorithmException: SunTlsRsaPremasterSecret KeyGenerator not available at javax.crypto.KeyGenerator.<init>(DashoA13*..) at javax.crypto.KeyGenerator.getInstance(DashoA13*..) at com.sun.net.ssl.internal.ssl.JsseJce.getKeyGenerator(JsseJce.java:223) at com.sun.net.ssl.internal.ssl.RSAClientKeyExchange.<init>(RSAClientKeyExchange.java:89) ... 22 more I've googled the error message and most of posts says it's because JVM cannot find sunjce_provider.jar. However, I can find the file in /Library/Java/Home/lib/ext folder. The platform is Mac OS X 10.6 and Java version is 1.6.0_17. My questions are: Why JVM does not search /Library/Java/Home/lib/ext for jar files? Can we change CLASSPATH or java.ext.dirs property by modify any config file? Any suggestion to solve this problem? Thanks in advance.

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  • Focusable EditText inside ListView

    - by Joe
    I've spent about 6 hours on this so far, and been hitting nothing but roadblocks. The general premise is that there is some row in a ListView (whether it's generated by the adapter, or added as a header view) that contains an EditText widget and a Button. All I want to do is be able to use the jogball/arrows, to navigate the selector to individual items like normal, but when I get to a particular row -- even if I have to explicitly identify the row -- that has a focusable child, I want that child to take focus instead of indicating the position with the selector. I've tried many possibilities, and have so far had no luck. layout: <ListView android:id="@android:id/list" android:layout_height="fill_parent" android:layout_width="fill_parent" /> Header view: EditText view = new EditText(this); listView.addHeaderView(view, null, true); Assuming there are other items in the adapter, using the arrow keys will move the selection up/down in the list, as expected; but when getting to the header row, it is also displayed with the selector, and no way to focus into the EditText using the jogball. Note: tapping on the EditText will focus it at that point, however that relies on a touchscreen, which should not be a requirement. ListView apparently has two modes in this regard: 1. setItemsCanFocus(true): selector is never displayed, but the EditText can get focus when using the arrows. Focus search algorithm is hard to predict, and no visual feedback (on any rows: having focusable children or not) on which item is selected, both of which can give the user an unexpected experience. 2. setItemsCanFocus(false): selector is always drawn in non-touch-mode, and EditText can never get focus -- even if you tap on it. To make matters worse, calling editTextView.requestFocus() returns true, but in fact does not give the EditText focus. What I'm envisioning is basically a hybrid of 1 & 2, where rather than the list setting if all items are focusable or not, I want to set focusability for a single item in the list, so that the selector seamlessly transitions from selecting the entire row for non-focusable items, and traversing the focus tree for items that contain focusable children. Any takers?

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  • 'NoneType' object has no attribute 'get' error using SQLAlchemy

    - by Az
    I've been trying to map an object to a database using SQLAlchemy but have run into a snag. Version info if handy: [OS: Mac OSX 10.5.8 | Python: 2.6.4 | SQLAlchemy: 0.5.8] The class I'm going to map: class Student(object): def __init__(self, name, id): self.id = id self.name = name self.preferences = collections.defaultdict(set) self.allocated_project = None self.allocated_rank = 0 def __repr__(self): return str(self) def __str__(self): return "%s %s" %(self.id, self.name) Background: Now, I've got a function that reads in the necessary information from a text database into these objects. The function more or less works and I can easily access the information from the objects. Before the SQLAlchemy code runs, the function will read in the necessary info and store it into the Class. There is a dictionary called students which stores this as such: students = {} students[id] = Student(<all the info from the various "reader" functions>) Afterwards, there is an "allocation" algorithm that will allocate projects to student. It does that well enough. The allocated_project remains as None if a student is unsuccessful in getting a project. SQLAlchemy bit: So after all this happens, I'd like to map my object to a database table. Using the documentation, I've used the following code to only map certain bits. I also begin to create a Session. from sqlalchemy import * from sqlalchemy.orm import * engine = create_engine('sqlite:///:memory:', echo=False) metadata = MetaData() students_table = Table('studs', metadata, Column('id', Integer, primary_key=True), Column('name', String) ) metadata.create_all(engine) mapper(Student, students_table) Session = sessionmaker(bind=engine) sesh = Session() Now after that, I was curious to see if I could print out all the students from my students dictionary. for student in students.itervalues(): print student What do I get but an error: Traceback (most recent call last): File "~/FYP_Tests/FYP_Tests.py", line 140, in <module> print student File "/~FYP_Tests/Parties.py", line 30, in __str__ return "%s %s" %(self.id, self.name) File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/SQLAlchemy-0.5.8-py2.6.egg/sqlalchemy/orm/attributes.py", line 158, in __get__ return self.impl.get(instance_state(instance), instance_dict(instance)) AttributeError: 'NoneType' object has no attribute 'get' I'm at a loss as to how to resolve this issue, if it is an issue. If more information is required, please ask and I will provide it.

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  • Apache HttpClient Digest authentication

    - by Milan Jovic
    Hi, Basically what I need to do is to perform digest authentication. First thing I tried is the official example available here. But when I try to execute it(with some small changes, Post instead of the the Get method) I get a org.apache.http.auth.MalformedChallengeException: missing nonce in challange at org.apache.http.impl.auth.DigestScheme.processChallenge(DigestScheme.java:132) When this failed I tried using: DefaultHttpClient client = new DefaultHttpClient(); client.getCredentialsProvider().setCredentials(new AuthScope(null, -1, null), new UsernamePasswordCredentials("<username>", "<password>")); HttpPost post = new HttpPost(URI.create("http://<someaddress>")); List<NameValuePair> nvps = new ArrayList<NameValuePair>(); nvps.add(new BasicNameValuePair("domain", "<username>")); post.setEntity(new UrlEncodedFormEntity(nvps, HTTP.UTF_8)); DigestScheme digestAuth = new DigestScheme(); digestAuth.overrideParamter("algorithm", "MD5"); digestAuth.overrideParamter("realm", "http://<someaddress>"); digestAuth.overrideParamter("nonce", Long.toString(new Random().nextLong(), 36)); digestAuth.overrideParamter("qop", "auth"); digestAuth.overrideParamter("nc", "0"); digestAuth.overrideParamter("cnonce", DigestScheme.createCnonce()); Header auth = digestAuth.authenticate(new UsernamePasswordCredentials("<username>", "<password>"), post); System.out.println(auth.getName()); System.out.println(auth.getValue()); post.setHeader(auth); HttpResponse ret = client.execute(post); ByteArrayOutputStream v2 = new ByteArrayOutputStream(); ret.getEntity().writeTo(v2); System.out.println("----------------------------------------"); System.out.println(v2.toString()); System.out.println("----------------------------------------"); System.out.println(ret.getStatusLine().getReasonPhrase()); System.out.println(ret.getStatusLine().getStatusCode()); At first I have only overridden "realm" and "nonce" DigestScheme parameters. But it turned out that PHP script running on the server requires all other params, but no matter if I specify them or not DigestScheme doesn't generate them when I call its authenticate() method. I've been struggling with this for two days, and no luck. Based on everything I think that the cause of the problem is the PHP script. It looks to me that it doesn't send a challenge when app tries to access it unauthorized. Any ideas anyone?

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  • Using Artificial Intelligence (AI) to predict Stock Prices

    - by akaphenom
    Given a set of datavery similar to the Motley Fool CAPS system, where individual users enter BUY and SELL recommendations on various equities. What I would like to do is show each recommendation and I guess some how rate (1-5) as to whether it was good predictor<5 (ie corellation coeffient = 1) of the future stock price (or eps or whatever) or a horrible predictor (ie corellation coeffient = -1) or somewhere inbetween. Each recommendation is tagged to a particular user, so that can be tracked over time. I can also track market direction (bullish / bearish) based off of something like sp500 price. The components I think that would make sense in the model would be: user direction (long/short) market direction sector of stock The thought is that some users are better in bull markets than bear (and vice versa), and some are better at shorts than longs- and then a cobination the above. I can automatically tag the market direction and sector (based off the market at the time and the equity being recommended). The thought is that I could present a series of screens and allow me to rank each individual recommendation by displaying available data absolute, market and sector out performance for a specfic time period out. I would follow a detailed list for ranking the stocks so that the ranking is as objective as possible. My assumtion is that a single user is right no more than 57% of the time - but who knows. I could load the system and say "Lets rank the recommendation as a predictor of stock value 90 days forward"; and that would represent a very explicit set of rankings. NOW here is the crux - I want to create some sort of machine learning algorithm that can identify patterns over a series of time so that as recommendations stream into the application we maintain a ranking of that stock (ie. similar to correlation coeeficient) as to the likelihood of that recommendation (in addition to the past series of recommendations ) will affect the price. Now here is the super crux. I have never taken an AI class / read an AI book / never mind specific to machine learning. So I cam looking for guidance - sample or description of a similar system I could adapt. Place to look for info or any general help. Or even push me in the right direction to get started... My hope is to implment this with F# and be able to impress my friends with a new skillset in F# with an implementation of machine learnign and potentially something (application / source) I can include in a tech portfolio or blog space; Thank you for any advice in advance.

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  • Using Objective-C Blocks

    - by Sean
    Today I was experimenting with Objective-C's blocks so I thought I'd be clever and add to NSArray a few functional-style collection methods that I've seen in other languages: @interface NSArray (FunWithBlocks) - (NSArray *)collect:(id (^)(id obj))block; - (NSArray *)select:(BOOL (^)(id obj))block; - (NSArray *)flattenedArray; @end The collect: method takes a block which is called for each item in the array and expected to return the results of some operation using that item. The result is the collection of all of those results. (If the block returns nil, nothing is added to the result set.) The select: method will return a new array with only the items from the original that, when passed as an argument to the block, the block returned YES. And finally, the flattenedArray method iterates over the array's items. If an item is an array, it recursively calls flattenedArray on it and adds the results to the result set. If the item isn't an array, it adds the item to the result set. The result set is returned when everything is finished. So now that I had some infrastructure, I needed a test case. I decided to find all package files in the system's application directories. This is what I came up with: NSArray *packagePaths = [[[NSSearchPathForDirectoriesInDomains(NSAllApplicationsDirectory, NSAllDomainsMask, YES) collect:^(id path) { return (id)[[[NSFileManager defaultManager] contentsOfDirectoryAtPath:path error:nil] collect:^(id file) { return (id)[path stringByAppendingPathComponent:file]; }]; }] flattenedArray] select:^(id fullPath) { return [[NSWorkspace sharedWorkspace] isFilePackageAtPath:fullPath]; }]; Yep - that's all one line and it's horrid. I tried a few approaches at adding newlines and indentation to try to clean it up, but it still feels like the actual algorithm is lost in all the noise. I don't know if it's just a syntax thing or my relative in-experience with using a functional style that's the problem, though. For comparison, I decided to do it "the old fashioned way" and just use loops: NSMutableArray *packagePaths = [NSMutableArray new]; for (NSString *searchPath in NSSearchPathForDirectoriesInDomains(NSAllApplicationsDirectory, NSAllDomainsMask, YES)) { for (NSString *file in [[NSFileManager defaultManager] contentsOfDirectoryAtPath:searchPath error:nil]) { NSString *packagePath = [searchPath stringByAppendingPathComponent:file]; if ([[NSWorkspace sharedWorkspace] isFilePackageAtPath:packagePath]) { [packagePaths addObject:packagePath]; } } } IMO this version was easier to write and is more readable to boot. I suppose it's possible this was somehow a bad example, but it seems like a legitimate way to use blocks to me. (Am I wrong?) Am I missing something about how to write or structure Objective-C code with blocks that would clean this up and make it clearer than (or even just as clear as) the looped version?

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  • Any significant performance improvement by using bitwise operators instead of plain int sums in C#?

    - by tunnuz
    Hello, I started working with C# a few weeks ago and I'm now in a situation where I need to build up a "bit set" flag to handle different cases in an algorithm. I have thus two options: enum RelativePositioning { LEFT = 0, RIGHT = 1, BOTTOM = 2, TOP = 3, FRONT = 4, BACK = 5 } pos = ((eye.X < minCorner.X ? 1 : 0) << RelativePositioning.LEFT) + ((eye.X > maxCorner.X ? 1 : 0) << RelativePositioning.RIGHT) + ((eye.Y < minCorner.Y ? 1 : 0) << RelativePositioning.BOTTOM) + ((eye.Y > maxCorner.Y ? 1 : 0) << RelativePositioning.TOP) + ((eye.Z < minCorner.Z ? 1 : 0) << RelativePositioning.FRONT) + ((eye.Z > maxCorner.Z ? 1 : 0) << RelativePositioning.BACK); Or: enum RelativePositioning { LEFT = 1, RIGHT = 2, BOTTOM = 4, TOP = 8, FRONT = 16, BACK = 32 } if (eye.X < minCorner.X) { pos += RelativePositioning.LEFT; } if (eye.X > maxCorner.X) { pos += RelativePositioning.RIGHT; } if (eye.Y < minCorner.Y) { pos += RelativePositioning.BOTTOM; } if (eye.Y > maxCorner.Y) { pos += RelativePositioning.TOP; } if (eye.Z > maxCorner.Z) { pos += RelativePositioning.FRONT; } if (eye.Z < minCorner.Z) { pos += RelativePositioning.BACK; } I could have used something as ((eye.X > maxCorner.X) << 1) but C# does not allow implicit casting from bool to int and the ternary operator was similar enough. My question now is: is there any performance improvement in using the first version over the second? Thank you Tommaso

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  • NTRU Pseudo-code for computing Polynomial Inverses

    - by Neville
    Hello all. I was wondering if anyone could tell me how to implement line 45 of the following pseudo-code. Require: the polynomial to invert a(x), N, and q. 1: k = 0 2: b = 1 3: c = 0 4: f = a 5: g = 0 {Steps 5-7 set g(x) = x^N - 1.} 6: g[0] = -1 7: g[N] = 1 8: loop 9: while f[0] = 0 do 10: for i = 1 to N do 11: f[i - 1] = f[i] {f(x) = f(x)/x} 12: c[N + 1 - i] = c[N - i] {c(x) = c(x) * x} 13: end for 14: f[N] = 0 15: c[0] = 0 16: k = k + 1 17: end while 18: if deg(f) = 0 then 19: goto Step 32 20: end if 21: if deg(f) < deg(g) then 22: temp = f {Exchange f and g} 23: f = g 24: g = temp 25: temp = b {Exchange b and c} 26: b = c 27: c = temp 28: end if 29: f = f XOR g 30: b = b XOR c 31: end loop 32: j = 0 33: k = k mod N 34: for i = N - 1 downto 0 do 35: j = i - k 36: if j < 0 then 37: j = j + N 38: end if 39: Fq[j] = b[i] 40: end for 41: v = 2 42: while v < q do 43: v = v * 2 44: StarMultiply(a; Fq; temp;N; v) 45: temp = 2 - temp mod v 46: StarMultiply(Fq; temp; Fq;N; v) 47: end while 48: for i = N - 1 downto 0 do 49: if Fq[i] < 0 then 50: Fq[i] = Fq[i] + q 51: end if 52: end for 53: {Inverse Poly Fq returns the inverse polynomial, Fq, through the argument list.} The function StarMultiply returns a polynomial (array) stored in the variable temp. Basically temp is a polynomial (I'm representing it as an array) and v is an integer (say 4 or 8), so what exactly does temp = 2-temp mod v equate to in normal language? How should i implement that line in my code. Can someone give me an example. The above algorithm is for computing Inverse polynomials for NTRUEncrypt key generation. The pseudo-code can be found on page 28 of this document. Thanks in advance.

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