On Thu, Aug 12, 2021 at 06:20:23PM +0200, Magnus Hagander wrote: > On Thu, Aug 12, 2021 at 4:38 PM hubert depesz lubaczewski > <depesz@xxxxxxxxxx> wrote: > > > > On Thu, Aug 12, 2021 at 11:32:15AM +0200, Magnus Hagander wrote: > > > Which database are you connected to? If you just want to look at the > > > global stats, it might help to be connected to a database that is > > > *not* the one with all the tables in -- e.g. connect to "postgres" and > > > query pg_stat_database looking for values on a different database? In > > > this case it would open files for "global", for "database postgres" > > > and "shared relations" only and skip the file for your db with many > > > objects. I think. > > > > I'm connected to the db I need data about, and I need data from virtualy > > all columns of pg_stat_database. > Try connecting to a different database, while still querying all columns. Damn, this is huge difference: =$ time psql -d postgres -c "select * from pg_stat_database where datname = 'appdb'" -qAtX > /dev/null real 0m0.058s user 0m0.026s sys 0m0.013s =$ time psql -d appdb -c "select * from pg_stat_database where datname = 'appdb'" -qAtX > /dev/null real 0m0.466s user 0m0.031s sys 0m0.008s Not sure if I can make the monioring software use different connection for this one particular query, though. Will check with them. Thanks. Best regards, depesz
