When you have a slow database app, the first suggestions that people make is to:
Track the slow queries
Add appropriate indexes
In the case you are building your own application this is very logical, but when you use a CMS like Drupal, that are people have developed and tuned, is this approach valid?
I mean, aren't Drupal tables already fine-tuned for performance? Even if I try to see which queries are the slow ones, what could I do about it? Re-write Drupal core?!?