Memory refers to the physical devices used to store programs or data on a temporary or permanent basis for use in a computer or other digital electronic device.

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Why the overhead when allocating objects/arrays in Java?

How many bytes an array occupies in Java? Assume It's a 64bit machine and also assume there are N elements in an array, so all these elements would take up 2*N, 4*N or 8*N bytes for different types of ...
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6answers
991 views

Term for 24-bits

Is there a term for a 24-bit (3-byte) integer? I know uncommon bit counts (such as a "nibble" or "nybble" for 4 bits) have names, and having 24-bits in both video and audio technology, for instance, ...
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4answers
2k views

Analyzing Memory Usage: Java vs C++ Negligible?

How does the memory usage of an integer object written in Java compare\contrast with the memory usage of a integer object written in C++? Is the difference negligible? No difference? A big difference? ...
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1answer
613 views

How are new[] and malloc implemented in Windows?

So when you call malloc or new [] from your C/C++ application, how does the CRT translate it into Windows API calls?
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4answers
878 views

strategies to keep tabs of memory leaks in non memory-managed languages

When it comes to non memory managed languages such as C, C++ or Fortran (my case), it becomes increasingly difficult to keep track of memory allocation/deallocation, especially when ownership must be ...
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1answer
386 views

GDI low on memory

I am fresh to Visual C++. While moving forward in the book "Programming Windows with MFC", I came across GDI (Graphics Device Interface) and use of paint brush. The book says a brush cannot be created ...
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2answers
723 views

Windows Physical Direct Memory Mapping

I'm a bit disappointed there is almost no discussion of this no matter where I look so I guess I'll have to ask. I'm writing a cross platform memory bench marking application which requires direct ...
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1answer
212 views

non-volatile virtual memory for C++ containers

Is there a virtual memory management process that would allow a program to use the standard container structures and classes, but retain these structures and their data when the program is not running ...
6
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5answers
476 views

On mobile is there a reason why processes are often short lived and must persist their state explicitly?

Most mobile platforms (such as Android, iOS, Windows phone 7 and I believe the new WinRT) can kill inactive application processes under memory pressure. To prevent this from affecting the user ...
2
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1answer
217 views

List structures in memory

Could anyone give an overview of how list structures which are composed of a head and a tail which references the rest of the list i.e linked list are represented in memory of the computer? Does the ...
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3answers
1k views

Can coding style cause or influence memory fragmentation?

As the title states, I'd like to know if coding style can cause or influence memory fragmentation in a native application, specifically one written using C++. If it does, I'd like to know how. An ...
2
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1answer
1k views

What metrics should be used to measure memory consumption of a program for performance test?

I am asked to provide performance statistics for a program, one of them being memory consumption. I noticed that in perfmon or in .NET API there is apparently many variable related to memory usage, ...
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4answers
4k views

Where are null values stored, or are they stored at all?

I want to learn about null values or null references. For example I have a class called Apple and I created an instance of it. Apple myApple = new Apple("yummy"); // The data is stored in memory ...
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4answers
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How can I monitor the JVM memory in a proper way?

I'm thinking of how we do JVM memory monitor in a low overhead way in production environment even under busy hour. Suppose I have two tomcat app server in production, load balance set up behind them. ...
4
votes
4answers
575 views

Manual memory allocation and purity

Language like Haskell have concept of purity. In pure function, I can't mutate any state globally. Anyway Haskell fully abstracts memory management, so memory allocation is not a problem here. But if ...
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5answers
14k views

Why does IIS default to Recycling the Application Pool every 1740 minutes?

Why does IIS default to recycle the app pool after a given time? Is there some specific reason other than perhaps most web apps are not managing the memory prudently? Given that you are managing your ...
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3answers
138 views

Using “prevent execution of method” flags

First of all I want to point out my concern with some pseudocode (I think you'll understand better) Assume you have a global debug flag, or class variable named "debug", class a : var debug = ...
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votes
4answers
618 views

What factors should I consider when choosing names for identifiers?

What factors do I need to consider when choosing names for identifiers such as variables? I am concerned about space issues, i.e. extra memory consumption when choosing longer names. As an example, ...
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5answers
3k views

Do threads use virtual memory or real memory?

I was trying to optimize my Linux server to handle 10,000 threads per process while it does just 382 right now. As per this article the following formula is used to find out total possible threads: ...
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1answer
682 views

Confused About Virtual Memory for All Processes

I hope this is the right place. This is a homework assignment for my Operating Systems course and I have to implement a working virtual memory system in C++ so programming is directly involved. I've ...
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3answers
2k views

Choose C++ or Java for applications requiring huge amounts of RAM? [closed]

I'm thinking of scientific applications that are mostly processor-bound and heavy on heap usage (at least several gigabytes). Any other time of the year I would happily go with C++, but in this case I ...
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2answers
2k views

Custom heap allocators

Most programs can be quite casual about heap allocation, even to the extent that functional programming languages prefer to allocate new objects than modify old ones, and let the garbage collector ...
2
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3answers
1k views

A good analogy for computer memory? [closed]

So, I'm a computer science major and I'm also a huge fan of the no-longer-on-TV show, Numb3rs. Now, whenever I talk with my friends they also ask me quite a few questions about programming and ...
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2answers
141 views

Design review for application facing memory issues

I apologise in advance for the length of this post, but I want to paint an accurate picture of the problems my app is facing and then pose some questions below; I am trying to address some self ...
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2answers
2k views

When I should I use message passing over shared memory?

I know a little about how to use message passing and shared memory, but I still don't know when to choose one or another. Can you tell me about their traits (not the implementation)?
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11answers
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Could it be more efficient for systems in general to do away with Stacks and just use Heap for memory management?

It seems to me that everything that can be done with a stack can be done with the heap, but not everything that can be done with the heap can be done with the stack. Is that correct? Then for ...
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7answers
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In C++, how much programmer time is spent doing memory management

People who are used to garbage collected languages are often scared of C++'s memory management. There are tools, like auto_ptr and shared_ptr which will handle many of the memory management tasks for ...
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11answers
761 views

Infinite Bitmap

I'd like to build a bitmap during runtime. The bitmap should be scalable on all sides and pixel access should be quiet efficient. Between and after the commands shown in the picture, Map.setPixel() ...
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2answers
827 views

One global HashMap vs. many local HashMaps?

Which is more efficient; which is faster? Trade-offs? Goal is for fast look-ups in a web application. UUIDs are the keys, so global will work. Approx 50 million values. A global cache is ...
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6answers
2k views

Addressable memory unit

From Wikipedia: the term endian or endianness refers to the ordering of individually addressable sub-components within a longer data item as stored in external memory (or, sometimes, as ...
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3answers
532 views

Is .Net memory hungry?

A friend of mine told me that .NET Framework is memory hungry and he gave me an example that if I make an application (in .NET web forms) which will take 20 mb of your RAM, it will be actually wasting ...
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1answer
85 views

where to allocate the room for new enviroment variable?

in unix, i want to modify enviroment variables. if size of new value is larger than the old one, the room for the new variable is allocated by malloc. however, is memory for enviroment variables above ...
31
votes
5answers
64k views

Stack and Heap memory in Java

As I understand, in Java, stack memory holds primitives and method invocations and heap memory is used to store objects. Suppose I have a class class A { int a ; String b; ...
4
votes
2answers
1k views

Smart Pointers inside class vs Normal Pointers with Destructor

Regarding pointers which are members of classes. Should they be of a smart pointer type or is it enough to simply deal with them in the destructor of the class they are contained in?
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5answers
783 views

The Default State of Unused Memory

In an embedded device, during the initializing of memory locations, is there any convention that are being practiced. I mean, say setting every byte to zero or 0xFF or any other value.
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11answers
927 views

Have you dealt with space hardening?

I am very eager to study best practices when it comes to space hardening. For instance, I've read (though I can't find the article any longer) that some core parts of the Mars rovers did not use ...