Re: pg_stat_activity showing non-existent processes

"Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov> writes:
> Is there any way to tweak this in favor of more accurate information,
> even if has a performance cost? We're finding that during normal
> operations we're not seeing most connections added to the
> pg_stat_activity table. We would like to be able to count on accurate
> information there.

That's basically a non-starter because of the delay in reporting from
the stats collector process (ie, even if the information was "completely
accurate" it'd still be stale by the time that your code gets its hands
on it). I think you'd be talking about a complete redesign of the stats
subsystem to be able to use it that way.

Having said that, though, I'd be pretty surprised if the stats subsystem
was dropping more than a small fraction of messages --- I would think
that could only occur under very heavy load, and if that's your normal
operating state then it's time to upgrade your hardware ;-). Maybe you
should investigate a bit more closely to find out why it's dropping so
much.

regards, tom lane