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.

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The Five Principles of Performance

In Demand IT Skills

The consulting industry is fiercely competitive and nets between $130B and $150B a year. In fact, professional consultants earn more money than many lawyers, doctors and other professionals. 

Offering free consultations is a common way for a software consultant to seize new accounts. But is there a red flag where a consultant may be giving away too many services for free? The worst scenario for a professional software consultant is to offer free services to the client and then never hear from them again once they no longer need their help. 

Although having the best intentions, many people will waste a consultant's time (i.e., client ignores or rejects any suggested approaches or solutions given by the consultant and seek the services of someone who will do it cheaper or will attempt to do it themselves). Small business owners especially can be challenging to work with. Some clients have a tendency to jump into projects before having adequate resources to finish what they have started, decide to go in a different direction midstream, while others simply don't want to spend any money when getting professional services. It's hard to believe, but some clients actually expect to receive free services for life. To counteract this notion, a software consultant can draw the line by offering free services within a promotional time frame and then begin charging a fee for services rendered after that time.

A good indicator of what a client's true intentions are is to monitor their activity within a specified period to see if their consultation activity bears fruit in the form of a contract. One big red flag is non-commitment on the part of the client. If they seem indecisive or vague about what they want it may be time to move on. Although there are times when a free consultation results in a paying client years later, who can wait that long? 

Less of Your Time is Wasted When You're Upfront

After being burned, some professional software consultants no longer give free consulting. They find that clients are much more willing to follow their advice when they have paid something. In order to close an account, a happy medium can be agreed upon by both parties involved as a way to build a long term relationship with highly qualified prospects. 

A software consultant's work, knowledge, skills and time are valuable. They can offer a potential client general solutions instead of addressing specific challenges. If a specific topic of discussion, troubleshooting session or other issue needs to be addressed, the consultant can inform the client of any upfront costs to receive a particular service if they need further assistance. Really, a free software consultation (if one is given) should be presented in a very similar way someone would hand out samples of a product at a grocery store. A professional consultant ideally wants clients to see how they can benefit using their services on a trial basis with a pitch leading to more extensive services which would only be available if they sign a contract with their firm. 

 Red Flags

A business rule is the basic unit of rule processing in a Business Rule Management System (BRMS) and, as such, requires a fundamental understanding. Rules consist of a set of actions and a set of conditions whereby actions are the consequences of each condition statement being satisfied or true. With rare exception, conditions test the property values of objects taken from an object model which itself is gleaned from a Data Dictionary and UML diagrams. See my article on Data Dictionaries for a better understanding on this subject matter.

A simple rule takes the form:

if condition(s)

then actions.

An alternative form includes an else statement where alternate actions are executed in the event that the conditions in the if statement are not satisfied:

if condition(s)

then actions

else alternate_actions

It is not considered a best prectice to write rules via nested if-then-else statements as they tend to be difficult to understand, hard to maintain and even harder to extend as the depth of these statements increases; in other words, adding if statements within a then clause makes it especially hard to determine which if statement was executed when looking at a bucket of rules. Moreoever, how can we determine whether the if or the else statement was satisfied without having to read the rule itself. Rules such as these are often organized into simple rule statements and provided with a name so that when reviewing rule execution logs one can determine which rule fired and not worry about whether the if or else statement was satisfied. Another limitation of this type of rule processing is that it does not take full advantage of rule inferencing and may have a negative performance impact on the Rete engine execution. Take a class with HSG and find out why.

Rule Conditions

Planning on a little spring cleaning and getting rid of all those old electronics? With the way technology changes so quickly, it seems like we no sooner have one new electronic piece and there’s a new one on the market that we absolutely have to have. The result is a ton of used electronics stored away. Now it’s time to get rid of everything, here are some tips on what to do with all that old tech stuff and how to do it safely.

Save on Landfill Waste

Few people really realize where their electronics wind up when they throw them in the trash or dumpster. They assume they’re getting taken care of and just forget about them. According to the Environmental Protection Agency, one of the fastest growing components of landfill waste is electronics. The unfortunate part of this is that these electronics are filled with lead, mercury and other toxic chemicals – chemicals that find their way into our soil and water.

This results in the contamination of our lakes, streams and soil. The best way to avoid this is by knowing where your electronics are going and to dispose of them safely. Contact the recycling center in your area and ask for the best place to dispose of your old electronics.

Think of Security

Our lives are filled with electronic technology, whether it’s in the form of computers, tablets, smart phones or video games. Most of these electronics allow network sharing with people all over the world. With identity theft such a growing concern, much of our private lives and personal information is entered in the hard drives of these items.

Before you dispose of any electronics, make sure the hard drives are wiped clean of all personal information. This requires more than just “deleting” files. If you’re not sure how to correctly get rid of the information, contact a professional to do this for you. Even if you have to pay to have it done, it’s a minimal expense compared to having your private information stolen.

Find New Homes for Your Electronics

Once you’ve cleaned out your electronics of personal information, they may still be worth something to other individuals. You may know of a child or elderly person who would really appreciate a “new” computer or a tablet. Someone who has never owned a smart phone or laptop may be thrilled to suddenly own one, even if they are obsolete to you.

If you can’t find anyone that wants them, consider selling them on places like eBay, Craigslist or one of the many other online auction sites. The old saying, “one man’s junk is another man’s gold” is especially true when it comes to electronics. Many people like building computers using their own parts.

Students in computer-related programs also utilize used electronics as a form of hands-on training. Most schools also take in donated computers, televisions and cell phones. Contact your electric company or school district to get information on where you can take your old electronics. You’ll be not only cleaning out your house but also helping the environment.

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Cloud Computing: What It Means and How It Could Threaten the Traditional Outsourcing Model