Get information about using jvm memory in java code

There are many ways to analyze jvm memory usage offline, like MAT, jmap. However, is there any way to measure the memory usage inside the code during the runtime? Any advice will be much appreciated.Please refer to the official Java documentation, i.

Deinit did not call a UIViewController, but Dealloc is

It seems like the Swift equivalent of dealloc is deinit. However, when you attempt to define the method on a UIViewController, it doesn't behave as you would expect... Setup Create a new Single View project using Xcode 7.0, in either Swift or Objecti

Implementation of the storage in separate memory (malloc) in C

I'm trying to implement my own malloc using a segregated free list (using this textbook as a reference:, but I'm not sure how to start. I have a method, malloc_init() that uses sbrk to return a slab of memory. Within the con

allocate random no. bytes in c

This question already has an answer here: 64 bit large mallocs 9 answers How can I dynamically allocate random no. of bytes in C? (say) I want to allocate 10 GB of memory, how can I do that and which function would be better to use here, as in malloc

Calculation of the memory space occupied by unordered cards

I have two unordered maps: (code is executed in linux) First unordered map: It consists of more atleast 65536 entries. Each entry consists of int unsigned char unsigned char Second unordered map: It consists of less than 65536 enteries. Each entry co

Using memory-mapped files for temporary tables in the program?

I'm currently writing a program which shall be able to handle out of core data. So I'm processing files from the size starting at 1MB up to 50GB (and possibly larger in future). I have read several tutorials regarding memory mapped files and am now u

Overloaded istream operator with dynamic memory allocation

Hello so I am confused with my istream& operator>>. I have to overload this operator to take input for a class that is using dynamic memory allocation for a C string. My Employee.h file is #include <iostream> using namespace std; const dou

Where and how __bridge

I need some advice on __bridge-ing in iOS. Hopefully the SSCCE1 below will explain the problem better than I can in words, but I need to know how I can convert a void* to an NSMutableArray*; which __bridge variation should be used (See comment in cod

Allocate memory and generate C structures

I'm trying to work through Kernighan's book "C Programming Language" to teach myself C in preparation for a data structures class this spring (C is a required prerequisite), but am stuck on how to deal with multiple structures and how you would

How do memory leak checkers like Valgrind identify for free?

I want to understand how does memory leak checkers identify if a free has been called for a given malloc. malloc can easily be identified by brk system calls, so if i am writing a profiler and do a single stepping on a process which breaks at system

Memory management, things to clear

I need to get things clear about Objective-C memory management: If I declare an object in the class header as ivar without @property: @interface MyFacebooDelegate : UIViewController { TableViewController *tableController; } ... @end and some where in

Local variables versus member variables in Objective-C

I am currently learning about memory management and properties in Objective-C. I recently read through this post and answers to my previous question concerning how @property and @synthesize work in Objective-C. This has clarified things somewhat. It

Is it a good idea to self self object with allowance

I am doing some allocation as = [[NSDictionary alloc] init]; Is it a good idea of retaining a property such like that? Or will it be better to do such as: NSDictionary *zzz = [[NSDictionary alloc] init]; = zzz; [zzz release]; My con

Mechanics of memory with scope

If I do something like // global scope function stuff() { // local scope var a = new SomeHugeMemoryHog(); } // a doesn't exist down here, but what happened to the memory from the "stuff" scope? Will I create a memory leak if I don't set a = null

details of the MESI protocol for multicore processors

The details of the MESI protocol for multicore processors would be really important for me, but I can't find them anywhere. Even doesn't co

Stenographic way to release all preserved properties?

We all know an object's properties should be released through its dealloc method, but often for objects with many properties this can be pretty cumbersome. It's kind of a headache especially when adding or removing new properties to remember to go ba

MPMoviePlayerController still flees

I release the MPMoviePlayerController but the memory allocation and the living objects are still higher than before the object allocation. However if I reallocate the object it doesn't leak more. My application actually uses a lot of media files and

Linux C debug library to detect memory corruption

When working sometimes ago on an embedded system with a simple MMU, I used to program dynamically this MMU to detect memory corruptions. For instance, at some moment at runtime, the foo variable was overwritten with some unexpected data (probably by

Named Pipe Strategies with Dynamic Memory?

Hokay so I have an application where I need some IPC... I'm thinking named pipes are the way to go because they are so easy to use. Anyways, I have a question about how to handle dynamic memory using named pipes. Say I have a class such as this: clas