memory

C++ object in memory

Hello. Is there a standard in storing a C++ objects in memory? I wish to set a char* pointer to a certain address in memory, so that I can read certain objects' variables directly from the memory byte by byte. When I am using Dev C++, the variables are stored one by one right in the memory address of an object in the order that they were...

C++ method parameter passed by reference - memory question

Assume, void proc(CString& str) { str = "123"; } void runningMethod() { CString str="ABC"; proc(str); } I understand that at the exit of runningMethod str will be deallocated automatically; in this case, how does C++ delete the old data ("ABC")? Thanks, Gil. ...

Are strings pooled in Python

Does Python have a pool of all strings and are they (strings) singletons there? More precise, in the following code one or two strings were created in memory: a = str(num) b = str(num) ? ...

displaying keyboard raises memory... but it never comes down iPhone

Hello again. I encountered a weird behavior in memory just by displaying the default keyboard. I've just created a project with an .xib file for testing purposes. This .xib file has an UITextField element in it and it's connected in the .h via: @property(nonatomic, retain) IBOutlet UITextField *sometext; The .m has no changes but: @...

Why is my UITableView getting its images messed up?

I'm trying to get my UITableView to show cells with images placed on them (contained in a UIImageView overlaid). I'm wondering why when scrolling up and down, the images look like they're overlaid on top of one another. What can I do in this case for the sake of memory management as well as to fix this issue? ...

Strange error when filling a data adapter.

I am receiving the following error in my code (c#, .Net 3.5, VS2008) when I try to connect to an Excel sheet and fill a OleDbDataAdapter with the results of a query. First the error: Attempted to read or write protected memory. This is often an indication that other memory is corrupt. And here is the code, which is honestly pre...

In java if i extend a class and don't use a super field while redefing every function does the field still uses memory?

It's all in the title. ...

Did anyone give these smart pointers (auto_any, scoped_any, shared_any) a test drive?

I'm investigating smart pointers with "shared" functionality for Windows CE and Mobile, where the VS 2008 tr1 std::shared_ptr cannot be used (due to linkage to a v.9 dll not present on CE, obviously, if I understand it correctly). There's a semi-old MSDN Magazine article with sources from a Microsoftie (Eric Niebler): Achieve More Relia...

Win32/MFC: How to find free memory (RAM) available?

Any suggestions/hints/links/tutorials would be appreciated! :) ...

If my application doesn't use a lot of memory, can I ignore viewDidUnload:?

My iPhone app generally uses under 5MB of living memory and even in the most extreme conditions stays under 8MB. The iPhone 2G has 128MB of RAM and from what I've read an app should only expect to have 20-30MB to use. Given that I never expect to get anywhere near the memory limit, do I need to care about memory warnings and setting ob...

Can immutable be a memory hog?

Let's say we have a memory-intensive class like an Image, with chainable methods like Resize() and ConvertTo(). If this class is immutable, won't it take a huge amount of memory when I start doing things like i.Resize(500, 800).Rotate(90).ConvertTo(Gif), compared to a mutable one which modifies itself? How to handle a situation like th...

Memory Allocation for a Map with a fixed number of insertions

I want to insert n elements into a map where n is known ahead of time. I do not want memory allocation at each insertion. I want all memory allocation at the beginning. Is there a way to do this? If so, how? Will writing some sort of memory allocator help? I ran GMan's code and got the following output. GetMem is printed from a call to ...

JQuery or javascript to find memory usage of page

Is there a way to find out how much memory is being used by a web page, or by my jquery application? Here's my situation: I'm building a data heavy webapp using a jquery frontend and a restful backend that serves data in JSON. The page is loaded once, and then everything happens via ajax. The UI provides users with a way to create m...

Adding images to an array memory issue

Hello all, I'm currently facing the following issue: My app dynamically creates images (320 x 480 pixels) and adds them to a NSMutableArray. I need those images inside that array in order to allow users to browse through them back and forth. I only need to keep the latest 5 images. So I wrote a method like below: - (void)addImageToArr...

Postgres - run a query in batches?

Is it possible to loop through a query so that if (for example) 500,000 rows are found, it'll return results for the first 10,000 and then rerun the query again? So, what I want to do is run a query and build an array, like this: $result = pg_query("SELECT * FROM myTable"); $i = 0; while($row = pg_fetch_array($result) ) { $myArray[$...

32 vs 64 bit...or, what exactly does 'processing information' mean

I am having trouble understanding the difference between a 32 bit processor and 64 bit processor. I know that a 32 bit processor can access 32 bits at a time while a 64 bit processor can access 64 bits at a time. But what exactly does it mean to access a certain number of bits at one time? ...

Java -Xms initial size effects

Hi. What is the benefit of setting the -Xms parameter, and having the initial memory larger for example, then the default calculated one (64 MB in my case, according to Java GC tunning: http://java.sun.com/javase/technologies/hotspot/gc/gc_tuning_6.html#par_gc.ergonomics.default_size)? Also, is there any good to setting both the initia...

What is the complexity of the below code with respect to memory ?

Hi, I read about Big-O Notation from here and had few questions on calculating the complexity.So for the below code i have calculated the complexity. need your inputs for the same. private void reverse(String strToRevers) { if(strToRevers.length() == 0) { return ; } else { ...

Dynamic memory managment under Linux

I know that under Windows, there are API functions like global_alloc() and such, which allocate memory, and return a handle, then this handle can be locked and a pointer returned, then unlocked again. When unlocked, the system can move this piece of memory around when it runs low on space, optimising memory usage. My question is that is...

Cocoa Memory Usage

I'm trying to track down some peculiar memory behavior in my Cocoa desktop app. My app does a lot of image processing using NSImage and uploads those images to a website over HTTP using NSURLConnection. After uploading several hundred images (some very large), when I run Instrument I get no leaks. I've also run through MallocDebug and ...