This article's intent is to demystify some of the definitions surrounding the topic of database performance, and to put a framework around what database performance truly is. Whether a seasoned veteran or a beginner, the arena of database performance should not be confusing.
Most of the database performance books, or seminars have the same typical overtones to them. They typically present individual tuning solutions to narrow problems. While solving problems is all good and well, many beginners and veterans alike easily get confused when trying to piece the full puzzle of database performance together. Many books and seminars usually leave the reader/attendee with the following question:
- Why does this problem exist?
- What area of the database is the problem affecting?
- What other areas of the database is the problem affecting?
- Is it possible to measure if the tuning has been successful?
- Are there steps to take if the tuning attempt has not been successful?
- Are there any other ways to solve the same problem?
To get a grasp on some of these questions, the following framework is proposed. The framework should be followed, to categorize the performance attempts. Once the areas of performance tuning are categorized, it is possible to achieve a richer understanding of what the database is doing, and what affects it.
What Is Performance
It is generally agreed that performance is important, but what is performance? Performance can be defined as the ability of a system to deliver the results based on the request of the users, while keeping them satisfied. The key point to remember is satisfaction. If current database key indicators reveal that the database is running optimally, but users are not satisfied with the response times, is there a need for tuning? The answer is yes, (within reason, of course). Typically, if one looks closely enough, there is usually something that can be done to make users happier, or at least more educated.
Since the Christmas Season has just passed, let's compare performance to the task of putting up Christmas lights. In this instance, performance is the ability to put the lights up in a reasonable amount of time, before it gets dark, and before we get too cold (satisfaction).