In programming, memory leaks are a common issue, and it occurs when a computer uses memory but does not give it back to the operating system. Experienced programmers have the ability to diagnose a leak based on the symptoms. Some believe every undesired increase in memory usage is a memory leak, but this is not an accurate representation of a leak. Certain leaks only run for a short time and are virtually undetectable.

Memory Leak Consequences

Applications that suffer severe memory leaks will eventually exceed the memory resulting in a severe slowdown or a termination of the application.

How to Protect Code from Memory Leaks?

Preventing memory leaks in the first place is more convenient than trying to locate the leak later. To do this, you can use defensive programming techniques such as smart pointers for C++.  A smart pointer is safer than a raw pointer because it provides augmented behavior that raw pointers do not have. This includes garbage collection and checking for nulls.

If you are going to use a raw pointer, avoid operations that are dangerous for specific contexts. This means pointer arithmetic and pointer copying. Smart pointers use a reference count for the object being referred to. Once the reference count reaches zero, the excess goes into garbage collection. The most commonly used smart pointer is shared_ptr from the TR1 extensions of the C++ standard library.

Static Analysis

The second approach to memory leaks is referred to as static analysis and attempts to detect errors in your source-code. CodeSonar is one of the effective tools for detection. It provides checkers for the Power of Ten coding rules, and it is especially competent at procedural analysis. However, some might find it lagging for bigger code bases.

How to Handle a Memory Leak

For some memory leaks, the only solution is to read through the code to find and correct the error. Another one of the common approaches to C++ is to use RAII, which an acronym for Resource Acquisition Is Initialization. This approach means associating scoped objects using the acquired resources, which automatically releases the resources when the objects are no longer within scope. RAII has the advantage of knowing when objects exist and when they do not. This gives it a distinct advantage over garbage collection. Regardless, RAII is not always recommended because some situations require ordinary pointers to manage raw memory and increase performance. Use it with caution.

The Most Serious Leaks

Urgency of a leak depends on the situation, and where the leak has occurred in the operating system. Additionally, it becomes more urgent if the leak occurs where the memory is limited such as in embedded systems and portable devices.

To protect code from memory leaks, people have to stay vigilant and avoid codes that could result in a leak. Memory leaks continue until someone turns the system off, which makes the memory available again, but the slow process of a leak can eventually prejudice a machine that normally runs correctly.

Related:

The Five Principles of Performance

In Demand IT Skills

This section of our beginning python training class always stumps students.  Firstly, because they need to know the difference between a function and a method.  Secondly, they need to understand object oriented programming concepts.  Thirdly, they need to realize that python has three types of methods.  Then they need to know how to use each method, which means they need to know the purpose of each method type.  Then they have to understand mutable versus non-mutable types.  The list goes on.  As part of our python tutorial, I hope to shed some light on this confusing topic.

To begin, the difference between a function and a method in python is that a method is defined within a class.  Here is an illustration:

#function

	def greeting():
	                print "Hello, I hope you're having a great day!"

	class HSGPrinter(object):
	                #method
	                def greeting(self): 
	                                print "Hello, I hope you're having a great day!"

As should be obvious, the second definition of greeting is encapsulated within the HSGPrinter class and is , therefore, refered to as a method.

The astute reader will notice that the greeting method contains one parameter named self.  For those who know C++ , Java or C#, self is equivalent to this i.e. it is a reference to the invoking object:

HP is taking legal action against Oracle for allegedly breaching its 2010 partnership agreement of porting HP’s core software products with the latest versions of Itanium. In March, Oracle announced it would not be developing any new versions for products designed for the Itanium processor. Itanium has the ability to power the so-called Business Critical Systems hardware for extremely demanding enterprise applications. However, Oracle said the chip line is about to die.

The companies’ lawyer met in the Santa Clara County Superior Court with Judge James Kleinberg presiding to discuss their side of the event. Others in the courtroom included Ann Livermore, HP board member and former enterprise business chief, and Oracle’s co-President Safra Catz. Catz and Livermore were the two key negotiators for the agreement. Livermore was to testify later in the day. Kleinberg is set to rule if the companies had a legally binding contract.

Jeff Thomas, HP’s lawyer, focused on the so-called Hurd Agreement wording, where the companies reiterated their partnership after Oracle hired Mark Hurd, former CEO for HP. HP also sued Hurd for breaking the confidentiality agreement.

Thomas and the lead lawyer for Oracle focused on one paragraph of the agreement, which read Oracle would continue to provide its product suite on the HP platform in a way that’s consistent with the existing partnership before Hurd’s hiring.

C TRAINING – THE THREE MAIN STAGES OF PROGRAMMING DEVELOPMENT

If you are an aspiring programmer, learning about programming in C is one of the most integral steps of your development.  It is essential that you get the highest quality C training, so that you are well-grounded in the language, and are going to be able to fulfill most of your programming and developmental tasks.  Learning about all aspects of the programming language, including how to fully utilize its portability and design will help you to secure your future in computer programming.  These are some of the concepts you should familiarize yourself with:

·         Major elements of the programming language – This includes things like libraries of functions, using data flow control, and a thourough examination of the basic data types the language is able to address.  As you learn about these fundamental elements, make sure to get practical experience during the course of your C training also, by actually writing programs that follow whatever curriculum you have chosen.

·         Different techniques and other programming elements – Different series of coursework choose to emphasize different things, but try to learn as much as you can about different techniques that are actually employed.  Manipulating both characters and strings, allocating dynamic memory in the proper manner, defining macros, and utilizing the runtime library are all examples of these elements.