Let's say I have a program(C++, for example) that allocates multiple objects, never bigger than a given size(let's call it MAX_OBJECT_SIZE). I also have a region(I'll call it a "page") on the heap(allocated with, say, malloc(REGION_SIZE), where REGION_SIZE >= MAX_OBJECT_SIZE). I keep reserving space in that page until the filled space e...
i have been following this course in youtube and it was talking about how some programmers can use there knowledge of how memory is laid to do clever things.. one of the examples in the lecture was something like that #include <stdio.h> void makeArray(); void printArray(); int main(){ makeArray(); printArray(); r...
my code is given below NSMutableArray *arrayBookMark = nil; sqlite3_stmt *selectStatement = nil; NSString * strSql = [NSString stringWithFormat:@"SELECT bokmark_id,pdf_id,pdf_name,bookmark_name,pageno,imagedata,createddate from bookmarks"]; int returnValue = sqlite3_prepare_v2(database, [strSql UTF8String], -1, &selectStatement, NULL); ...
What follows is an initializer method. It creates a Movie structure from a file, with an eye to extracting the raw pixels for processing, as per Apple QA1443. This is then wrapped in a QTMovie – sourceMovie = [QTMovie movieWithQuickTimeMovie: ...] – for convenience. After initializing such an object, the second method is called, and we ...
I am considering to use BDB XML, as in memory application data store. It is XML like data with definition records and data records, i have provided XPath like quiring for data access. Its running well except for a memory overflow problem, that occurs in some cases which can't be avoided (so, just ant to avoid mem-overflow), and data is s...
Why is paging out policy based on exploiting the concept of locality and working set likely to perform well? ...
OK, This is a method from my program that keeps giving the EXC_BAD_ACCESS error and crashing. I indicated the line below. questionsShown is a readwrite property and points to an NSMutableArray that I initialize with a capacity of 99 at an earlier point in the program. When I debug everything appears normal in terms of the property being ...
We develop an application in an embedded environment. It is a high level computing environment with a complete webbrowser on top of a busybox Linux system. The only exception is that the system has a limited amount of system memory. Our application is built in JavaScript and runs inside a Webkit based webbrowser and consists of a lot of...
Hi all, I'm facing this problem in which my allocated variabls aren't getting allocated even if their retaincount is increamenting after every alloc/retain. NSMutableArray *companyArray = [[NSMutableArray alloc]init]; doesn't allocate companyArray but increaments the retain count of companyArray. If I print the description of it, the...
This is an object I made to do some flash cards. The first method (I left out the main part) generates a NSMutabaleArray of Card objects with the passed in operator and works fine. The second method, "drawFromDeck" gets called on a Deck object from my view controller and also works fine, but the Static Analyzer says I may be leaking an...
I have a class here that is defined like this: struct USERFPOINT { POINTFLOAT UserPoint; POINTFLOAT LeftHandle; POINTFLOAT RightHandle; bool isBezier; }; struct SHAPEOUTLINE { GLuint OutlineVBO; int OutlineSize; int OutlineWidth; ARGBCOLORF OutlineColor; }; struct SHAPECONTOUR{ std::vector<USERFPOI...
In C++ I'm using boost::shared_ptr and boost::weak_ptr to automatically delete objects that are no longer needed. I know these work with reference counting. In Java, memory is managed by a garbage collector, which consideres the built-in object references as strong, WeakReference as weak and SoftReference as something in between (may be...
1) For which datatypes must I allocate memory with malloc? For types like structs, pointers, except basic datatypes, like int For all types? 2) Why can I run this code? Why does it not crash? I assumed that I need to allocate memory for the struct first. #include <stdio.h> #include <stdlib.h> typedef unsigned int uint32; typedef st...
Or in other words why would I need to retain the object returned by [NSManagedObjectModel mergedModelFromBundles]. Is there any memory menagement rule explicitly guiding me to retain it? I assume the retain count is 0 on return. ...
I am looking for a way to cure at least the symptoms of a leaky DLL i have to use. While the library (OpenCascade) claims to provides a memory manager, i have as of yet being unable to make it release any memory it allocated. I would at least wish to put the calls to this module in a 'sandbox', in order to keep my application from not l...
We have a small text box with 512Mb of ram. We wanted to see how many threads we can create in Java in this box. To our surprise, we can't create many. Essentially the minimum stack size you can set with -Xss is 64k. Simple math will tell you that 64*7000 will consume 430Mb so we were only able to get it up to around 7000 threads or so a...
I push a view controller into current navigation controller. It works fine, except when I am getting out of the current view controller, it crashes. MyTableView *newPage = [[MyTableView alloc] initWithNibName:@"table2" bundle:nil]; [[self navigationController] pushViewController:newPage animated:YES]; //[newPage release]; I comment ou...
Hi, I have a scenario that I'm not sure whether to retain a view controller or not. Say I had ViewControllerOne. When a button was pressed, ViewControllerOne would push ViewControllerTwo in the navigation stack. ViewControllerTwo needs a reference to ViewControllerOne because it needs to access an ivar in that view controller. The quest...
This question was asked to me in an interview: In C++, what if we allocate memory using malloc and use delete to free that allocated memory? what if we allocate the memory using new and free it using free? What are the problems that we would face if the above things are used in the code? My answer was there is no...
I am writing an Excel File using Apache POI. I want to write in it all the data of myResultSet which has the fieldnames(columns) stored in the String[] fieldnames. I have 70000 rows and 27 columns My Code: String xlsFilename = "myXLSX.xlsx"; org.apache.poi.ss.usermodel.Workbook myWorkbook = new XSSFWorkbook(); org.apache.poi.ss.user...