David Fowler looks for the biggest, meanest database on a SQL Server instance:
I’m sure we’ve all been there at some point, sometimes it’s easy to tell. We might only have a handful of databases on the server with one known to be the heaviest utilised. But sometimes things might not be so obvious, there could be a large numbers of databases or no obvious resource hog.
In those instances we need some way to figure out what how much time each database is spending on the CPU if that’s what we’re interested in or perhaps the total number of page reads or writes if IO is our problem.
Read on for one way to do this, assuming that the instance has been up long enough to give you reliable results.