Search Results

Search found 4838 results on 194 pages for 'binary heap'.

Page 111/194 | < Previous Page | 107 108 109 110 111 112 113 114 115 116 117 118  | Next Page >

  • A quick over view of facebook's db?

    - by Matt
    Hey guys I find it hard to believe that Facebook uses simple sql, surely it would use some other method but lets assume for now it does use sql how would the code assimilating the 'wall' work? Lets say that there is three tables (just for the example) Friends: id (entry key) - uid(your id) - fid (your mates' id) Wall:id (entry key) - username - comment - time - commentcount comments: id (entry key) - wid (wall id (original comment)) - reply - time Lets forget about the like part and report etc, as well as mod things (ip, ban etc.) How would this work? Select wall.id, wall.username, wall.comment, wall.time, wall.commentcount, comments.wid, comments.reply, comments.time FROM wall inner join comments ON wall.id=comments.wid ORDER BY wall.time; That's your own wall but how do they get friend's? A heap of unions?

    Read the article

  • Is a class that is hard to unit test badly designed?

    - by Extrakun
    I am now doing unit testing on an application which was written over the year, before I started to do unit-testing diligently. I realized that the classes I wrote are hard to unit test, for the following reasons: Relies on loading data from database. Which means I have to setup a row in the table just to run the unit test (and I am not testing database capabilities). Requires a lot of other external classes just to get the class I am testing to its initial state. On the whole, there don't seem to be anything wrong with the design except that it is too tightly coupled (which by itself is a bad thing). I figure that if I have written automated test cases with each of the class, hence ensuring that I don't heap extra dependencies or coupling for the class to work, the class might be better designed. Does this reason holds water? What are your experiences?

    Read the article

  • global std::unordered_map com server init problems

    - by PrettyFlower
    I want to have a static global std::unordered_map in the cpp of my entry point for my COM server. relevant header code: typedef unordered_map<HWND,IMyInterface*> MyMapType; relevant body: static MyMapType MyMap; void MyFunction(HWND hWnd, IMyInterface* pObj){ MyMap[HWND] = pObj; } HINSTANCE g_hInstModule = NULL; BOOL WINAPI DllMain ( __in HINSTANCE hInstDLL, __in DWORD fdwReason, __in LPVOID lpvReserved ) { if( fdwReason == DLL_PROCESS_ATTACH ) { g_hInstModule = hInstDLL; return true; } else if( fdwReason == DLL_PROCESS_DETACH ) { return true; } return false; } MyCoClass::MyCoClass() { DRM_Refcount = 1; } HRESULT STDMETHODCALLTYPE MyCoClass::InitMyCoClass() { CoInitializeEx(NULL, COINIT_APARTMENTTHREADED); //replace with make window code MyFunction(hWnd,ISomeInterface); return S_OK; } The only way I can get this to work is be making a map_type pointer and creating an instance of map_type on the heap and pointing at it with the global pointer. :/ WHY?

    Read the article

  • Arrays & Pointers

    - by Thomas
    Hi, Looking for some help with arrays and pointers and explanation of what I am trying to do. I want to create a new array on the heap of type Foo* so that I may later assign objects that have been created else where to this array. I am having troubles understanding what I am creating exactly when I do something like the following. Foo *(*f) = new Foo*[10]; Also once I have created my array how do I access each element for example. (f + 9)->fooMember(); ?????? Thanks in advance.

    Read the article

  • Festival TTS showing SIOD:ran out off storage message

    - by Peeyush
    Hello i am designing a front end for Festival TTS using it's C++ API Everything is working fine in my programme but i have a problem that i am giving a drop down option to user to select other languages when user select a language from drop down then festival tts shows a message on console saying: SIOD:ran out of storage This message only shows if the text given to festival TTS is greater then 5 or 6 lines. i think this message comes because SIOD's heap is not free when i am going to call a new language. So please tell me the solution of this problem. Thanks

    Read the article

  • dangling pointer, reason for value change after free()?

    - by Aman Jain
    In the following code segment, after free(x), why does y becomes 0? As per my understanding, the memory in the heap that was being pointed to by x, and is still being pointed by y, hasn't been allocated to someone else, so how can it change to 0? And moreover, I don't think it is free(x) that changed it to 0. Any comments? #include <stdio.h> int main ( int argc, char *argv[] ) { int *y = NULL; int *x = NULL; x = malloc(4); *x = 5; y = x; printf("[%d]\n", *y); //prints 5 free(x); printf("[%d]\n", *y); //why doesn't print 5?, prints 0 instead return 0; }

    Read the article

  • Stopping pirates

    - by Pirate for Profit
    Okay, what do I do to stop pirates? Obviously a callhome to internet service. We are considering making some major aspects be dependent on a web service of some sort. Memory offsets and cracking. If I like rand randomly to allocate empty memory on the heap, would this throw off the crackers? I hacked some memory shit for EverQuest back in the dizzay but don't really know much about this. Registry on windows, etc., I know theres ways to identify the computer. That's easily spoofed with hex editor, but if I jumble up the strings in the program would that help? I need to know that + real ideas. I want the serials of their sound cards. Any other ideas?

    Read the article

  • Could not see memory being released on closing MFC modal dialog that hosts wpf user control using HW

    - by Naveen Chiluka
    This is in continuation with my last question posted "Continuous Memory leak while using WpfHWndSource" I have to load an WPF User Control in an MFC Modal Dialog that is being invoked from the ocx control. For this I have created a MFC Regular Dll(Mixed Mode Regular dll with clr option enabled), I have created a modal dialog which will host wpf user control using HWndSource. This exported dialog is placed as a child Dialog of the above MFC dialog that is being invoked from the ocx. Ny intermediate dialog uses C++/Cli code. When the main MFC dialog is closed, I am deleteing the ptr reference of the intermediate dialog created on the heap. In the the dipose of the .Net User Control, I have set most of the references that I have created to null, unsubscribed to the events (to avoid weak refernces), unbinded from the propertes(by using clear binding). Called delete on the HwndSource and the user control(which basically calls the dispose method). But I do not see complete memory being released. Any help would be greatful.

    Read the article

  • getting java.lang.OutOfMemoryError exception while running a Midlet (using netbeans)

    - by Jeeka
    I am writing a Midlet(using Netbeans) which reads a file containing exactly 2400 lines (each line being 32 characters long) and (extract a part of each line) puts them in an array. I am doing the same for 11 such files( all files have exactly 2400 lines).The Midlet runs fine for reading 6 files and putting them in 6 arrays. However, the Midlet stops while doing it for the 7th file throwing the following exception: TRACE: , startApp threw an Exception java.lang.OutOfMemoryError (stack trace incomplete) java.lang.OutOfMemoryError (stack trace incomplete) I have tried the modifying the netbeans.conf file to increase the heap memory ( as suggested by many forums and blogs) but nothing works for me. Here are the parameters that i had modified in the netbeans.conf file: -J-Xss2m -J-Xms1024m -J-Xmx1024m -J-XX:PermSize=1024m -J-XX:MaxPermSize=1536m -J-XX:+UseConcMarkSweepGC -J-XX:+CMSClassUnloadingEnabled -J-XX:+CMSPermGenSweepingEnabled Can anyone please help me to get me out of this ! I badly need this to be sorted out ASAP ! Thanks in advance !

    Read the article

  • Meaning of the "Unloading class" messages

    - by elec
    Anyone can explain why the lines below appear in the output console at runtime ? (one possible answer would be full permGen, but this can be ruled out since the program only uses 24MB out of the max100MB available in PermGen) [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor28] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor14] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor4] [Unloading class sun.reflect.GeneratedMethodAccessor5] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor38] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor36] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor22] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor8] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor39] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor16] [Unloading class sun.reflect.GeneratedSerializationConstructorAccessor2] [Unloading class sun.reflect.GeneratedConstructorAccessor1] The program runs with the following params: -Xmx160M -XX:MaxPermSize=96M -XX:PermSize=96M -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+PrintGCTaskTimeStamps -XX:+PrintHeapAtGC -XX:+PrintTenuringDistribution -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps -verbose:gc -Xloggc:/logs/gc.log There's plenty of space in the heap and in permGen.

    Read the article

  • Tuning JVM (GC) for high responsive server application

    - by elgcom
    I am running an application server on Linux 64bit with 8 core CPUs and 6 GB memory. The server must be highly responsive. After some inspection I found that the application running on the server creates rather a huge amount of short-lived objects, and has only about 200~400 MB long-lived objects(as long as there is no memory leak) After reading http://java.sun.com/javase/technologies/hotspot/gc/gc_tuning_6.html I use these JVM options -Xms2g -Xmx2g -XX:MaxPermSize=256m -XX:NewRatio=1 -XX:+UseConcMarkSweepGC Result: the minor GC takes 0.01 ~ 0.02 sec, the major GC takes 1 ~ 3 sec the minor GC happens constantly. How can I further improve or tune the JVM? larger heap size? but will it take more time for GC? larger NewSize and MaxNewSize (for young generation)? other collector? parallel GC? is it a good idea to let major GC take place more often? and how?

    Read the article

  • Forbid GridView to load all views at once

    - by efpies
    I have about 700 items to display in the grid view. On a Samsung Galaxy Tab 10.1 this is not a problem: it has enough memory. On a HTC Explorer the heap is overflown. So I want to load data dynamically regarding current scroll position (N rows for screen + 5 rows as a tail). And I want to show a scrollbar which represents the position in total rows. But I don't want to draw items that I don't see. In other words, I want to create something similar to UITableView in iOS. How can I do this?

    Read the article

  • Where in memory are stored nullable types?

    - by Ondrej Slinták
    This is maybe a follow up to question about nullable types. Where exactly are nullable value types (int?...) stored in memory? First I thought it's clear enough, as Nullable<T> is struct and those are value types. Then I found Jon Skeet's article "Memory in .NET", which says: Note that a value type variable can never have a value of null - it wouldn't make any sense, as null is a reference type concept, meaning "the value of this reference type variable isn't a reference to any object at all". I am little bit confused after reading this statement. So let's say I have int? a = null;. As int is normally a value type, is it stored somehow inside struct Nullable<T> in stack (I used "normally" because I don't know what happens with value type when it becomes nullable)? Or anything else happens here - perhaps in heap?

    Read the article

  • Transform PDF to HTML, keep layout

    - by Tgr
    What methods are there to transform a PDF to HTML? It could be anything - online service, software, library. (Opensource preferred. In the last case, php or python would be preferred.) It has to keep the original layout (including page numbers, footnotes and such), keep the images (combining them to one single background image per page is acceptable) and keep the links. It should preferably output valid XHTML and clean up PDF features such as ligatures, but if there is some post-processing required, I can live with that. Something with a clean, relatively semantic HTML output would be great. The closest one I found was zamzar.org, but it choked on links. (Also, the HTML output is an ugly heap of absolutely positioned divs and needs post-processing because of encoding problems.)

    Read the article

  • What is it about Fibonacci numbers?

    - by Ian Bishop
    Fibonacci numbers have become a popular introduction to recursion for Computer Science students and there's a strong argument that they persist within nature. For these reasons, many of us are familiar with them. They also exist within Computer Science elsewhere too; in surprisingly efficient data structures and algorithms based upon the sequence. There are two main examples that come to mind: Fibonacci heaps which have better amortized running time than binomial heaps. Fibonacci search which shares O(log N) running time with binary search on an ordered array. Is there some special property of these numbers that gives them an advantage over other numerical sequences? Is it a density quality? What other possible applications could they have? It seems strange to me as there are many natural number sequences that occur in other recursive problems, but I've never seen a Catalan heap.

    Read the article

  • "Ambiguous template specialization" problem

    - by Setien
    I'm currently porting a heap of code that has previously only been compiled with Visual Studio 2008. In this code, there's an arrangement like this: template <typename T> T convert( const char * s ) { // slow catch-all std::istringstream is( s ); T ret; is >> ret; return ret; } template <> inline int convert<int>( const char * s ) { return (int)atoi( s ); } Generally, there are a lot of specializations of the templated function with different return types that are invoked like this: int i = convert<int>( szInt ); The problem is, that these template specializations result in "Ambiguous template specialization". If it was something besides the return type that differentiated these function specializations, I could obviously just use overloads, but that's not an option. How do I solve this without having to change all the places the convert functions are called?

    Read the article

  • Leak caused by fread

    - by Jack
    I'm profiling code of a game I wrote and I'm wondering how it is possible that the following snippet causes an heap increase of 4kb (I'm profiling with Heapshot Analysis of Xcode) every time it is executed: u8 WorldManager::versionOfMap(FILE *file) { char magic[4]; u8 version; fread(magic, 4, 1, file); <-- this is the line fread(&version,1,1,file); fseek(file, 0, SEEK_SET); return version; } According to the profiler the highlighted line allocates 4.00Kb of memory with a malloc every time the function is called, memory which is never released. This thing seems to happen with other calls to fread around the code, but this was the most eclatant one. Is there anything trivial I'm missing? Is it something internal I shouldn't care about? Just as a note: I'm profiling it on an iPhone and it's compiled as release (-O2).

    Read the article

  • how much concurrent http request can erlang handle

    - by user209123
    I am developing a application for benchmarking purposes, for which I require to create large number of http connection in a short time, I created a program in java to test how much threads is java able to create, it turns out in my 2GB single core machine, the limit is variable between 5000 and 6000 with 1 GB of memory given to JVM after which it hits outofmemoryerror with heap limit reached. It is suggested around that erlang will be able to generate much more concurrent processes, I am willing to learn erlang if it is capable of solving the problem , although I am interested in knowing can erlang be able to say generate somewhere around 100000 processes which are essentially http requests waiting for responses, in a matter of few seconds without reaching any limit like memory error etc.,

    Read the article

  • java best way to transfer images

    - by d.raev
    I have a application that reads a PDF, transform the content to collection of TIF files, and send them to Glass Fish Server for saving. Usually there are 1-5 pages and it works nice, but when I got a input file with 100+ pages... it throws error on the transfer. Java heap space at java.util.Arrays.copyOf(Arrays.java:2786) at java.io.ByteArrayOutputStream.write(ByteArrayOutputStream.java:94) Putting more resources is not a good option in my case, so I m looking for a way to optimize it somehow. I store the data in: HashMap<TifProfile, List<byte[]> Is there a better way to store or send them ? EDIT I did some tests and the final collections for PDF with 80 pages has size over 280mb (240 tiffs with different settings inside)

    Read the article

  • Issue with Visual C++ 2010 (Express) External Tools command

    - by espais
    I posted this on SuperUser...but I was hoping the pros here at SO might have a good idea about how to fix this as well.... Normally we develop in VS 2005 Pro, but I wanted to give VS 2010 a spin. We have custom build tools based off of GNU make tools that are called when creating an executable. This is the error that I see whenever I call my external tool: ...\gnu\make.exe): * couldn't commit memory for cygwin heap, Win32 error 487 The caveat is that it still works perfectly fine in VS2005, as well as being called straight from the command line. Also, my external tool is setup exactly the same as in VS 2005. Is there some setting somewhere that could cause this error to be thrown?

    Read the article

  • How to attach boost::shared_ptr (or another smart pointer) to reference counter of object's parent?

    - by Checkers
    I remember encountering this concept before, but can't find it in Google now. If I have an object of type A, which directly embeds an object of type B: class A { B b; }; How can I have a smart pointer to B, e. g. boost::shared_ptr<B>, but use reference count of A? Assume an instance of A itself is heap-allocated I can safely get its shared count using, say, enable_shared_from_this.

    Read the article

  • Reallocating memory via "new" in C++

    - by BSchlinker
    Quick question regarding memory management in C++ If I do the following operation: pointer = new char [strlen(someinput_input)+1]; And then perform it again, with perhaps a different result being returned from strlen(someinput_input). Does this result in memory being left allocated from the previous "new" statement? IE, is each new statement receiving another block of HEAP memory from the OS, or is it simply reallocating? Assuming I do a final delete pointer[]; will that deallocate any and all memory that I ever allocated via new to that pointer? Thanks

    Read the article

  • Android: Is decreasing size of .png files have some effect to resulted Bitmap in memory

    - by nahab
    I'm writing game with a large amount of .png pictures. All worked fine. Than I added new activity with WebView and got memory shortage. After that I made some experiment - replace game .png images with ones that just fully filled with some color. As result memory shortage had gone. But I suppose that Bitmap internally hold each pixel separately so such changes should have no effect. Maybe this because of initial images have alpha channel and my test images have not it? But actually question is: Will decreasing .png images files sizes make some effect on decreasing usage of VM application heap or not?

    Read the article

  • Memory allocation for collections in .NET

    - by Yogendra
    This might be a dupe. I did not find enough information on this. I was discussing memory allocation for collections in .Net. Where is the memory for elements allocated in a collection? List<int> myList = new List<int>(); The variable myList is allocated on stack and it references the List object created on heap. The question is when int elements are added to the myList, where would they be created ? Can anyone point the right direction?

    Read the article

  • overview/history of resident memory usage

    - by kapet
    I have a fairly complicated program (Python with SWIG'ed C++ code, long running server) that shows a constantly growing resident memory usage. I've been digging with the usual tools for the leak (valgrind, Pythons gc module, etc.) but to no avail so far. I'm a bit afraid that the actual problem is memory fragmentation within Python and/or libc managed memory. Anyway, my question is more specific right now: Is there a tool to visualize resident memory usage and ideally show how it develops over time? I think the raw data is in /proc/$PID/smaps but I was hoping there's some tool that shows me a nice graph of the amounts used by mmap'ed files vs. anonymous mmap'ed memory vs. heap over time so that it's easier to see (literally) what's changing. I couldn't find anything though. Does anybody know of a ready to use tool that graphs memory usage over space and time in an intuitive way?

    Read the article

< Previous Page | 107 108 109 110 111 112 113 114 115 116 117 118  | Next Page >