Re: What kind of locks does vacuum process hold on the db?

On 8/30/07, Nitin Verma <nitinverma@azulsystems.com> wrote:
>
> >> Then you aren't doing regular vacuum often enough and / or don't have high
> enough fsm settings.
>
> Right now it's just default, can you please point me to a document that
> elaborates on calculation of FSM for a given load (or to say averaged load)

Run a full vacuum / reindex to reclaim the lost space.
Set up the autovacuum daemon to run.
After a day or so, vacuum all your databases, and on the last one do a
vacuum verbose.

At the end you'll have a few lines like this:

DETAIL:  A total of 9612 page slots are in use (including overhead).
9612 page slots are required to track all free space.
Current limits are:  153600 page slots, 1000 relations, using 965 kB.
VACUUM

So, I'm only using about 10,000 page slots out of a maximum of 153,600 slots.

If the number of pages slots requires exceeds your current limits then
you'll need to raise them.  If not, then autovacuum is doing its job.