As the load on a MySQL server increases, its performance often degrades if it has not been properly tuned to handle the load. Similarly, MySQL-based applications which perform well under small loads often do not scale well as their usage increases. This presentation describes various optimization and design techniques that can dramatically improve the performance and efficiency of MySQL servers and applications. Since "throwing hardware at the problem" is often not the best approach (or even possible), all of the ideas will focus on software related issues.