Re: Overhauling GUCS

Tom Lane wrote:
> How far could we get with the answers to just three questions:
> 
> * How many concurrent queries do you expect to have?
> * How much RAM space are you willing to let Postgres use?
> * How much "overhead" disk space are you willing to let Postgres use?

+1 to this approach - these are the kinds of questions that
make sense to me when first setting up a new installation.
They sound useful for both large servers and tiny (salesguy
laptop for demos) installations.

> If those aren't enough questions, what else must we ask? 

* Perhaps something to guess FSM settings?  I think FSM is  tunable I most often get wrong with more painful
consequences(bloat) than other tunables.  My approach is to have cron run database-wide vacuums  even on systems with
autovacuumjust to see the log  messages about FSM.
 

* Something to tune vacuum delay?  Perhaps:  How much I/O bandwidth can be dedicated to Postgres  background
activities?