Why software bugs exist and how you can help

Numbers in software development are represented by fixed size variables represented in binary. These are usually 8, 16, 32 or 64 bits (each bit represents a 1 or a 0). When we develop software, we choose which of these will provide enough space for the thing we are representing.

Recently, the Gangnam Style video on YouTube surpassed 2,147,483,647 views and it appeared as though the view counter broke. That number is significant because it is the upper limit of a 32-bit signed integer. It turns out that the video view count was being represented using a 32-bit signed integer — a signed value1 can represent whole numbers in the range -2,147,483,648 through 2,147,483,647; it cannot represent any number outside that range.

Though, according to YouTube, this turned out to be an Easter egg2, the bug was there before they updated the counter to 64-bit and it certainly is not the first time a number has pushed the limits. For example, the use of two digits to represent a year that contributed to the infamous fizzle that was Y2K.

But why? Why are there bugs at all?

Although it may seem like software bugs are there just to ruin your day, they were not intentionally put there or maliciously inserted to give you a reason to "Office Space" your device. As software engineers we have to consider a variety of constraints on the software we are developing. How much space does it need to run? How much space will there be on the device on which it is to run? How fast does it have to be?  How many years will the software be in use3? What other software will be running? And we have deadlines by which our work has to be completed. In fact, software engineers tend to consider a whole host of things such as the requirements of the software (functional, spatial, and temporal4), the specification of the system on which it is to execute, project deadlines and budgets, and the expectations of the end user.

Almost always, there has to be compromise. Even though a solution might be possible that accommodates all considerations, we have to deliver software in a time frame that people will pay for and some things just take too long or cost too much. That is not to say that all software bugs are because of time and money, some exist because of mistakes and as a consequence of poor design.

What does it all mean?

Software engineers like myself do not want you to encounter bugs. We work very hard and the QA teams work very hard to ensure that you do not get buggy software; if we see a problem, we do what we can to address it. To find these bugs, we try to consider all the ways our software might be used and test them. Unfortunately, most bugs do not advertise their existence quite so obviously or politely as YouTube's view counter bug. For example, when in comes to the infinite ways any one device might be configured with different peripherals and apps installed, we just cannot test them all; the system is too complex5.

 Good developers welcome user feedback. We need your help.

Next time you encounter a bug in the software you use, whether it is a mobile app, a website, an ATM, a desktop application, or some other device, spare a thought for the software engineers. Remember, good developers welcome user feedback. Take a moment to tell them or the publishers of the software about the problem.

  • What did you type, touch, or click?
  • What else was running on your device?
  • What part of the software were you in?
  • What Internet browser or operating system were you running?
  • What versions?

Be as detailed as you can. All these details and more can help a software engineer track down, reproduce and ultimately fix that bug.

There is no malice in a software bug. It was not put there specifically to ruin your day. However, without your help, it will not go away. So, reach out to the developers and tell them, they will thank you for it.

Today's featured image is based on Software Bugs by Martin Maciaszek.

  1. signed means it can be positive or negative []
  2. An Easter Egg is a hidden feature often added to software as an amusement for users who find it. Examples include the "barrel roll" in Google or the flight simulator in Excel []
  3. Underestimation of this was a big contributor to Y2K []
  4. i.e. how it works, what space it needs, and how long it takes to run and for how long it has to run []
  5. That's a discussion for another time []