As a DBA, I regularly observe my database, tune up some queries (either getting the programmers to re-write it or add index or update statistics if that's what is needed, etc). I also tune up the server options, etc.
But what I'm not happy with is that I don't have good metrics to say whether my work is worthwhile or not.
On one off queries optimization I can tell whether I got the query to run faster or not. I can use logs and pgfouine to detect slow queries.
But is there overall ways to quantify how well the database is running, metrics to keep track of that will tell me if I'm generally improving things or not really making a difference, etc?
I'm looking for metrics captured at the database level, not at the application level.