bakotat's blog

Earlier we've seen a model which estimates development costs and relates them to the maintainability of a system. We've also provided an alternative definition of maintainability (let's call it relative maintainability) which is not an absoulte value (contrary to most of the existing definitions), but it's value is particular at the beginning and it's change depends only on how the code has been changing.

Last time we estimated the cost of code change, now we'll try to reveal the connection of costs and maintenance.

Let's first suppose that the company we consider does not care about improving the code, it just fulfills the customer feature requests.
Suppose that a new feature request arrives (let's denote the feature by ).

Have you ever been wondering what does software maintenance cost? And how these costs split between separate development phases. In this section we are trying to find answers to this question by formal methods and by deriving several models that describe the different software development phases. Most of the presented models are linear ones, which can in some cases be easily justified, but in other cases we rely on empirical reasoning.

Let's get into it!