Sql. Monitoring. Partitioning. High Availability MySQL. Optimizing MySQL: Hardware and the Mysqld Variables. Like a grand prix driver starting at the back of the track, if you don't do things well from the beginning, and prepare hard for the race, it doesn't matter how well you do once the race has started.
You're at the back and are never going to win. So, with MySQL, it's extremely important to start off on the right foot, and that means compiling MySQL properly. The specific options you use depends on your setup of course, but here are some pointers to get you started. Firstly, compile statically (--static). This requires more disk space, but runs faster (13% on Linux, according to MySQL themselves) Optimize to the highest level possible (-O3 with gcc) Compile without debug (--without-debug). Optimizing MySQL: Queries and Indexes.
You know the scene.
The database is just too slow. Queries are queuing up, backlogs growing, users being refused connection. Adding New User Accounts to MySQL.